Dr Lydie Dussol
email: lydie.dussol@cepam.cnrs.fr

Dr Julien Sion
email: juliension@hotmail.fr

Dr Philippe Nondédéo
email: philippe_nondedeo@yahoo.com

Late fire ceremonies and abandonment behaviors at the Classic Maya city of Naachtun, Guatemala

Keywords: Maya, fire, anthracology, ritual deposit, abandonment, mobility, memory, Terminal Classic, Early Postclassic

This paper focuses on the process of abandonment in pre-Hispanic Maya societies. Toward the end of the Classic period (250-950 CE), the general desertion of the Central Lowland cities gave place to multiple actsincluding fires and on-floor ash spreadingintended to ritually terminate the occupation of houses and buildings. While the urban area of Naachtun, Northern Peten, was apparently depopulated by the end of the Terminal Classic (830-950 CE), fire ceremonies were performed in two political buildings during the Early Postclassic (950-1250 CE). The detailed study of the remaining charcoal deposits and their comparison with habitual Late and Terminal Classic abandonment deposits in households allows us to examine the material, social and environmental dimension of these fire ceremonies. We argue that these late rituals were held by people who were still tied to the city and that they are thus distinct from those performed as part of pilgrimages to sacred landscapes during the Late Postclassic and Colonial times. Instead, we state that they reflect the continuity of rites and of collective memory drawn from Naachtun's history, providing indirect evidence that human settlements persisted around the abandoned cities for some time after the collapse of Classic political systems.

Duca Foundation and the Excellence Cluster DynamiTe (ANR-11-LABX-0046) as part of the "Investissements d'Avenir" program.

List of tables

Table 1. Details of Group B deposits that underwent charcoal analysis. Density of macro-botanical remains is indicated only for flotation samples.

Table 2. Anthracological data (number of charcoal fragments per taxa) in Group B abandonment deposits.

Table 3. Radiocarbon dates for Group B deposits and domestic middens (IntCal13 atmospheric curve [START_REF] Reimer | Id number Description and location Age BP Calibrated intervals 2σ UBA-24869 Deposit #1[END_REF]).

List of figures

Introduction

The general desertion of the Central Maya Lowlands toward the end of the first millennium has been the subject of strong debate among the scientific community and the public. Since the ruins of ancient Maya cities were rediscovered early in the 19 th century, archaeologists have sought to understand the causes of what was called the collapse of Classic Maya civilization (e.g. [START_REF] Aimers | What Maya collapse? Terminal Classic variation in the Maya Lowlands[END_REF]Demarest et al., 2004;[START_REF] Turner | Classic Period collapse of the Central Maya Lowlands: insights about human-environment relationships for sustainability[END_REF]. The crises that characterized the end of the Late Classic and the Terminal Classic periods (750-950 CE) seem to have been multi-faceted (resource over-exploitation, overpopulation, migrations, warfare and climate change, etc.) and their impact on cities more or less slow and reversible depending on the resilience of each community. Increasing evidence indicates that people persisted around the depopulated cities or reinvested formerly abandoned zones, long after the departure of the majority of the inhabitants, which accompanied the disintegration of the Lowland social-political systems. Yet while focusing on the causes of these phenomena, little insight is provided on the way people themselves lived this period of disorder (Arnauld et al., 2017a).

Transitional stages of collapse and post-collapse are key, however, to understand the cognitive processes implied in the social and cultural changes within civilizations [START_REF] Diamond | Collapse: how societies choose to fail or succeed[END_REF][START_REF] Faulseit | Beyond collapse: archaeological perspectives on resilience, revitalization, and transformation in complex societies[END_REF]. During the Terminal Classic period (830-950 CE), the greater frequency of abandonment deposits, the only vestiges of the rites intended to symbolically close a place's occupation (Boteler-Mock, 1998), indicates the increasing concern of people faced with the abandonment of their living spaces.

When and where excavation programs have focused on abandonment dynamics, the detailed study of these material deposits on the buildings' floors have shown that, except in certain cases of escape due to violent circumstances (e.g. [START_REF] Inomata | Domestic and Political Lives of Classic Maya Elites: The Excavation of Rapidly Abandoned Structures at Aguateca, Guatemala[END_REF], the abandonment of Maya cities was progressive. Some families continued to live several decades beside houses already in ruins [START_REF] Lamoureux-St-Hilaire | The last groups standing: living abandonment at the ancient Maya center of Minanha, Belize[END_REF]. At the site of Naachtun, Northern Guatemala (Figure 1), a Central Lowland city occupied during the whole Classic period (150-950 CE), intensive excavations carried out for several years by the Naachtun Archaeological Project (2010-2018, CNRS, University of Paris 1 and University San Carlos of Guatemala) highlighted a complex set of depositions related to abandonment both in residential areas and in public buildings of the urban core [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF]. While the surrounding dwellings were abandoned between the end of the Late Classic and the Terminal Classic periods (800-950 CE), two monumental buildings, Structures 5O-5 and 6O-5, were the site of fire ceremonies during the Early Postclassic period (950-1250 CE) according to radiocarbon dating. Censer deposits associated with incense remains and large quantities of ashes and charcoal were discovered on the floors of these two buildings which successively hosted the political power during the Late and Terminal Classic periods (600-950 CE) [START_REF] Michelet | Operación III.1: Los edificios 6O3, 6O4, 6O5 y la Plaza Río Bec[END_REF][START_REF] Nondédéo | Operación III.2a: La Plaza Este y el palacio XXV[END_REF][START_REF] Nondédéo | Operación III.2a: Excavaciones en el palacio XXV[END_REF].

The performance of these fire rituals in such meaningful places after the last inhabitants had left the site core raises critical questions about the process of abandonment by the various social groups and about the dynamics of mobility after the collapse of Maya cities. Were these rituals performed by people who came back afterward to the city center as part of a pilgrimage journey? Or were they carried out by remaining inhabitants who still lived in the area long after the demise of the society? How do they relate to the abandonment rituals performed by the occupants leaving their households?

What collective memory and social identity do they reflect?

In this paper, we address the human behaviors related to abandonment in Maya cities, through an indepth analysis of abandonment and post-abandonment deposits at Naachtun. After emphasizing briefly the contribution of charcoal and fire studies to the understanding of ancient rituals, we outline the gradual process of abandonment of Naachtun's urban area from the end of the Late Classic to the Terminal Classic period (800-950 CE). We highlight the existence of two main patterns of abandonment deposits based on their charcoal composition and formation process. We then describe uncommon Early Postclassic deposits in two public buildings. This allows us to trace the origin of the fire ceremonies and understand their environmental context. Finally, we discuss the possible roles and implications of these late rituals in a post-collapse context.

Fire, ashes, and the study of ritual behaviors

Archaeologically, abandonment deposits at Maya Lowland sites are very often associated with ashes, charcoal and burn marks, attesting to the central role played by fire in termination rituals (e.g. [START_REF] Clayton | Rubbish or ritual? Contextualizing a problematical deposit at Blue Creek, Belize. A response to "Public architecture, ritual, and temporal dynamics at the Maya center of Blue Creek, Belize," by Thomas H. Guderjan[END_REF][START_REF] Pagliaro | Reevaluating the archaeological signatures of Maya ritual and conflict[END_REF][START_REF] Stanton | Garbage of the gods? Squatters, refuse disposal, and termination rituals among the Ancient Maya[END_REF]. These deposits generally consist of common objects broken and dispersed on floors, but they can also comprise a few artifacts laid in precise places such as a building's entrance and accesses. Archaeological context is key to define a particular deposit as probably related to an abandonment ritual, compared to simple domestic refuse for example [START_REF] Lamoureux-St-Hilaire | The last inhabitants of Minanha, Belize: examining the differential abandonment of an ancient Maya community[END_REF]. Axial placement, association with voluntary architectural destruction (fire, floor removal, burial reopening) or deposition of artifacts in unsealed holes, are indicators of an abandonment ritual (e.g. [START_REF] Barrientos | Los recintos funerarios y la veneración de los antepasados en los espacios habitacionales del Grupo B de Naachtun, Guatemala[END_REF][START_REF] Stanton | Garbage of the gods? Squatters, refuse disposal, and termination rituals among the Ancient Maya[END_REF]. In most cases, the conspicuous burn marks on the walls and floors where a termination ritual took place, or the presence of actual hearths provide direct evidence of in situ fires. In other cases, the role of fire is indirect. It is suggested by the deposition of ashes, censers or burnt artifacts which do not visibly result from an in situ fire. This archaeological evidence indicates nevertheless that the burning of incense or other objects was a critical step in ancient Maya ritual sequences.

Beyond the conventional study of artifacts and of the context, the analysis of carbonized plant remains allows us to reconstitute the botanical composition of the deposit, and thus to better understand ritual actions and behaviors in both their material and ideological dimensions. Archaeobotanical and anthracological studies conducted at Maya sites and elsewhere have shown that beside their fuel function, wood and plants burned as part of ancient rituals could have been selected specifically to fill other technical or symbolic purposes (e.g. [START_REF] Beauclair | Fire and ritual: bark hearths in South-American Tupiguarani mortuary rites[END_REF]Cenzon-Salvayre, 2014;[START_REF] Morehart | Wood of the gods: the ritual use of pine (Pinus spp.) by the ancient lowland Maya[END_REF]. Admittedly, it can be risky to put forward any symbolic explanation for the use of a particular plant in ancient rituals in the absence of written sources and based solely on the archaeological record. Nevertheless, the archaeobotanical study of ritual deposits can yield much information on their formation process. Composed hearths, successive deposition of plant material such as wooden objects, or the construction of perishable structures such as altars or funeral pyres, can result in stratified or spatially-organized deposits whose layout would go unnoticed without a thorough archaeobotanical sampling [START_REF] Cenzon-Salvayre | L'apport des données anthracologiques à l'interprétation des pratiques funéraires de l'Antiquité[END_REF]. By bringing to light the actions responsible for the formation of ritual deposits and putting them into a spatial and temporal context, one clarifies the diversity and variability of ritual behaviors that convey a social and identity discourse as much as the symbols attached to the ritual paraphernalia.

Last occupancy and abandonment at Naachtun during the Terminal Classic

Covered today by a medium sub-perennial tropical forest [START_REF] Schulze | A classification and ordination of the tree community of Tikal National Park, Petén, Guatemala[END_REF], the site of Naachtun was significantly occupied since at least the end of the Preclassic period (150/200-300 CE).

The epicenter comprises three monumental groups named A, B and C, and is surrounded by a residential area of approximately 175 ha (Figure 1). Population dynamics and abandonment processes in the city throughout the Classic period have been reconstructed through 1) intensive excavations in several households of the epicenter, and 2) systematic pit survey and excavations in the settlement area [START_REF] Goudiaby | Pratiques funéraires et statut des morts dans les ensembles résidentiels mayas classiques[END_REF][START_REF] Hiquet | Households, growth, contraction and mobility at the Classic Maya center of Naachtun[END_REF][START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF]. Outside of this urban area, human occupation in the hinterland of Naachtun has only been confirmed by LiDAR images [START_REF] Canuto | Ancient lowland Maya complexity as revealed by airborne laser scanning of northern Guatemala[END_REF]Nondédéo et al., 2018a). In the current state of research, no chronological information from excavations is available regarding population dynamics in the hinterland.

Forming the east part of the epicenter, Group B (Figure 2) became the hub of political and economic activities after a political break occurred during the 6 th century. The relocation of the seat of power from Group A to Group B was materialized by the construction of the Eastern Plaza with its main structure 5O-5. This was accompanied by the building of the Western Complex, an elite residential compound that probably hosted the royal family during most of the Late Classic period (600-830 CE).

From the second half of the 8 th century, new political changes led to the construction of the Río Bec Plaza and two new elite residential compounds, the Central and Southern Complexes. New political buildings such as the pyramid 6O-3 and Structure 6O-5 shaped this new sector. This architectural renewal is interpreted as the expression of a desire to break away from the former period when Naachtun was subjugated to the Kanu'l dynasty of Calakmul (Nondédéo et al., 2013b). During this phase (750-830 CE), the population of Naachtun reached its apogee, as observed in many other Northern Peten cities [START_REF] Culbert | Precolumbian population history in the Maya Lowlands[END_REF]. Besides the densely populated households of Group B, around 60% of dwellings in the urban area were occupied at the end of the Late Classic period (Hiquet et al., 2018, n.d.).

Around 800 CE, Naachtun's royal dynasty collapsed, and the political authority apparently passed into the hands of new elite families living in the Southern Complex (Nondédéo et al., n.d.). These families maintained their prosperity until the end of the Terminal Classic (830-950 CE) by developing new exchange roads, as reflected in the diversity and richness of artifacts contained in the domestic middens of this post-dynastic period [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF][START_REF] Sion | Interactions between Naachtun and the Western Lowlands during the Late and Terminal Classic periods as evinced in ceramic assemblages[END_REF]. In the meantime however, and for unclear reasons, the people of Naachtun gradually left the city, while part of the remaining population apparently contracted around the residences of these new leading groups until at least the 10 th century.

Forty-eight percent of dwellings in the urban area remained occupied during the Terminal Classic, whereas the Early Postclassic occupation is limited to a single structure [START_REF] Hiquet | Households, growth, contraction and mobility at the Classic Maya center of Naachtun[END_REF].

The progressive abandonment of Naachtun's Group B from the end of the Late Classic resulted in a variety of deposits (including broken and burnt ceramic vessels, lithic tools, faunal remains, human bones, ashes and charcoal) that we interpret as the vestiges of ritual practices carried out by the inhabitants themselves at the time of departure (Figure 2). In the Southern Complex, evidence of these ritual events was particularly widespread and puzzling, especially in Patio 28 which was certainly home to the most powerful family of Naachtun during the Terminal Classic [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF].

The variations observed in these rituals seem to reflect spontaneous acts which apparently did not follow strict liturgical standards. Indeed, the prayers enunciated during these rites may have been as important as paraphernalia and actions, of breaking, spreading and burning objects [START_REF] Sion | Abandonando la casa: depósitos de última ocupación sobre pisos[END_REF]. Often, the similarities between the contents of the deposits and those of domestic middens suggest that the action of retrieving domestic trash and depositing it inside the buildings was a critical step in the abandonment process [START_REF] Halperin | Household garbage: Classic period (ca. 300-900 CE) Maya practices of discard[END_REF][START_REF] Newman | Rethinking refuse: a history of Maya trash[END_REF]. Daily life garbage seems to materialize residential permanency of sedentary life in stone houses. Masonry houses represent a larger investment than thatched roof dwellings that are more easily reconstructed, and a stronger territorial anchoring, showing a greater willingness of sedentariness of their inhabitants. This residential stability over time is manifested by the accumulation of domestic waste, which is then included in the rituals related to the abandonment of dwellings. Abandonment rituals also involved the remains of the deceased that had been buried under the houses' floors or integrated into caches related to dedicatory rituals or architectural modifications [START_REF] Barrientos | Los recintos funerarios y la veneración de los antepasados en los espacios habitacionales del Grupo B de Naachtun, Guatemala[END_REF][START_REF] Goudiaby | Pratiques funéraires et statut des morts dans les ensembles résidentiels mayas classiques[END_REF][START_REF] Pereira | Ash, dirt, and rock: burial practices at Río Bec[END_REF]. Ritual acts were somehow carried out by the living with the dead. Closing the house meant ending sedentary times in these stone houses where successive generations of people had lived and died [START_REF] Arnauld | Ritos de transición, ritos de crisis: perspectivas para la movilidad poblacional en las sociedades mayas clásicas[END_REF][START_REF] Sion | Abandonando la casa: depósitos de última ocupación sobre pisos[END_REF].

Anthracological analysis and formation processes of the deposits

Several abandonment deposits were identified in the households of the Southern, Central and Western Complexes of Group B and in the political buildings 5O-5 and 6O-5 [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF][START_REF] Nondédéo | Operación III.2a: La Plaza Este y el palacio XXV[END_REF][START_REF] Nondédéo | Operación III.2a: Excavaciones en el palacio XXV[END_REF][START_REF] Michelet | Operación III.1: Los edificios 6O3, 6O4, 6O5 y la Plaza Río Bec[END_REF]. Twenty of them were embedded in ashy matrices that were sampled for charcoal analysis in order to trace their origin (Table 1). The anthracological study of the deposits was carried out in parallel with a general study on firewood economy at Naachtun [START_REF] Dussol | Feux et forêts mayas. Usages et gestion des combustibles ligneux dans les Basses Terres centrales mayas à la période Classique : le cas du site de Naachtun, Petén, Guatemala, approche anthracologique[END_REF]. During excavations, soil samples of 5 to 20 liters depending on the deposit's extension were systematically taken. Carbonized macro-botanical remains were extracted through manual flotation of sediment through a 2 mm screen. Some ash and charcoal deposits in Structures 5O-5 and 6O-5 had been sampled manually during field seasons that preceded implementation of the flotation sampling protocol in 2013. These were dry-screened in laboratory. In the present case, the different strategy used to sample the deposits does not prevent their comparison, insofar as the interpretation of charcoal assemblages proceeding from direct fire events or specialized activities does not require the same standards, in terms of sampling and quantification methods, as those intended for paleoecological restitutions [START_REF] Chabal | L'anthracologie[END_REF][START_REF] Théry-Parisot | Anthracology and taphonomy, from wood gathering to charcoal analysis. A review of the taphonomic processes modifying charcoal assemblages in archaeological contexts[END_REF]. The samples were analyzed in the Archaeobotany laboratory of the University of Paris 1 (Nanterre) following standard anthracology methods [START_REF] Chabal | L'anthracologie[END_REF]. Identification of charcoal pieces of over 4 mm in size was based on Dussol's reference collection of Central-American wood [START_REF] Dussol | Feux et forêts mayas. Usages et gestion des combustibles ligneux dans les Basses Terres centrales mayas à la période Classique : le cas du site de Naachtun, Petén, Guatemala, approche anthracologique[END_REF] as well as on wood anatomy literature and databases (e.g. [START_REF] Barajas-Morales | Anatomía de maderas de México: especies de una selva alta perennifolia[END_REF][START_REF] Metcalfe | Anatomy of the dicotyledons: leaves, stem, and wood in relation to taxonomy, with notes on economic uses[END_REF][START_REF] Wheeler | Inside Wood -A web resource for hardwood anatomy[END_REF][START_REF] Wheeler | IAWA list of microscopic features for hardwood identification, with an appendix on non-anatomical information[END_REF]. In total, 2,144 charcoal fragments were analyzed including 106 unidentifiable fragments that were not included in data analysis. Sixty-one taxa were identified (Table 2). Description of their anatomical features and diagnosis for their identification are available in Dussol (2017, Appendix E).

When taking into account the process of deposition, the density of macro-botanical remains and the taxa richness and diversity (number and relative abundance of taxa), the household deposits display two main patterns of formation (Figure 3).

The first pattern corresponds to the remains of in situ fires as shown by the associated burn marks. It comprises Deposits #7, #17 and #20, along with Deposit #4 in the non-residential Structure 5O-4.

These generally display a higher remain density and a lower taxa diversity, which characterize a single fire event made of only one or two different kinds of wood. The less represented taxa in these deposits could correspond to small branches or twigs that were used to start the fire, or to post-depositional contamination.

The second pattern was found in Deposits #10, #12-14, #16 and #18. The absence of in situ burn marks indicates that they probably correspond to secondary ash deposits. They are characterized by a generally lower remain density and a higher taxa diversity compared to the total number of charcoal fragments (Deposit #10 yielded no less than 26 taxa for only 153 charcoal fragments). These deposits are similar to domestic refuse that contains the eroded remains of multiple fires made over a long time, explaining that they may yield only few charcoal fragments (e.g. only 30 and 22 identifiable charcoal fragments in Deposits #16 and #18) that nevertheless display a relatively higher diversity of taxa. This pattern suggests that ashes were gathered from domestic middens and relocated inside houses for ritual purposes. This hypothesis is supported by the frequency of ordinary ceramic shards and faunal remains in these secondary ash deposits, as usually found in middens [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF].

That being stated, some deposits cannot be clearly classified in one or the other category. Deposits #8, #9 and #11 are associated with burn marks but display quite diversified taxa spectra. Conversely, Deposit #19 is clearly a secondary deposit, but since it contains only large charcoal fragments (resulting in high remains density) of only one wood species, it probably results from a single fire event. Several scenarios could explain these intermediate cases. In any event, they indicate that a strict categorization of deposits based on their material composition and context might sometimes be insufficient to account for the diversity and variability of ritual behaviors, especially as many steps in the ritual sequence may leave no material traces.

A series of radiocarbon dating tests carried out on some deposits and domestic middens of Group B provided quite homogeneous dates ranging between 725 and 980 CE (Table 3). This corroborates a final occupation and abandonment of Group B between the end of the Late Classic and the end of the Terminal Classic periods. Based on ceramic analysis and stratigraphy, [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF] determined that the process of abandonment was gradual and that it certainly spanned more than a century. Indeed, the first abandonment rituals were performed as early as the final Late Classic in the Western Complex (e.g. Deposit #7). Furthermore, some of the Terminal Classic deposits were made in already collapsed structures (Deposits #17 and #20), while nearby houses were still inhabited. The following sections deal with the latest of these deposits, which distinguish themselves from the others not only by their late dating but also by their atypical pattern of formation.

The Early Postclassic deposits in Naachtun's political buildings

Structure 5O-5, Eastern Plaza

Located at the northern edge of the Eastern Plaza, Structure 5O-5 and adjacent buildings form a palatial compound which probably hosted political and administrative activities (Figure 2). We believe that this building was the seat of Naachtun's royal dynasty during the Late Classic (Nondédéo et al., 2013b, n.d.). Intensive excavations were carried out in 2011 and 2013 [START_REF] Escobar Durand | Operación III.2b: Sondeos en el Patio XXV-A[END_REF][START_REF] Nondédéo | Operación III.2a: La Plaza Este y el palacio XXV[END_REF][START_REF] Nondédéo | Operación III.2a: Excavaciones en el palacio XXV[END_REF][START_REF] Perla | Operación III.2b: Excavaciones en la Estructura XXV bis de la Plaza Este[END_REF]. The main structure was built at the beginning of the 7 th century.

It is composed of three rooms aligned on a west-east axis and opened to the south (Figure 4a). It stands on a monumental stepped platform, about 5 meters-high, giving direct access to the plaza. Consistent ash, charcoal and material deposits were found on the burnt stucco floors of the central and east rooms, as well as on the upper platform in front of the east room entrance (Figure 5). No ash deposit was detected in the west room despite the burn marks on its floor. This evidence indicates that fire rituals related to abandonment were performed in this building. Indeed, nothing in the regular occupation of the structure seems to justify the existence of functional hearths in those places.

The central room deposit (Deposit #1) was located in the very center of the room [START_REF] Nondédéo | Operación III.2a: La Plaza Este y el palacio XXV[END_REF]. It consists of a large concentration of burnt censer fragments, accompanied by a blend of ashes, charcoal and remains of burnt vegetal resin (evidenced by fluorescence under UV light, [START_REF] Colín | Operación VIa y VIb: Trabajos de conservación y restauración[END_REF]. All of this was set directly on the floor that was intensely burnt on an area of approximately 1.40 meters in diameter. Restoration work helped identify at least three different vessels: two big pedestal censers (Figure 6) and a small sahumador. [START_REF] Nondédéo | Operación III.2a: La Plaza Este y el palacio XXV[END_REF] states that according to the disposal of shards and debris, the censers had been placed intact on the floor and were then destroyed by the collapse of the roof.

This deposit originates unequivocally from an in situ fire that was lit as part of a ceremony performed between 1030 and 1260 CE according to two radiocarbon dates (Table 3). If we refer to the pattern of abandonment deposits observed at Naachtun, one would expect that this single fire event would contain only a few different types of wood. However, charcoal analyses showed that this fire was built with at least 13 taxa (among 213 charcoal fragments identified). The spectrum includes Sapotaceae (58 %), Sapindaceae (11 %) including guayo (Allophylus sp.) and possibly canchunup (Thouinia paucidentata), pine (Pinus sp., 8 %), goncalo alves (Astronium sp., 8 %), Jamaica dogwood (Piscidia piscipula, 5 %), Euphorbiaceae (4 %), craboo (Byrsonima sp., 2 %), a dalbergia species, possibly rosewood (Dalbergia stevensonii, 2 %), Moraceae (1.5 %) including breadnut (Brosimum alicastrum), possibly fustic (Maclura tinctoria) and annatto (Bixa sp., 0.5 %), and an undetermined taxon (0.5 %). This taxonomic richness is quite surprising for a single fire. Furthermore, the use of fustic and annatto as firewood is not documented elsewhere at Naachtun according to the anthracological data [START_REF] Dussol | Feux et forêts mayas. Usages et gestion des combustibles ligneux dans les Basses Terres centrales mayas à la période Classique : le cas du site de Naachtun, Petén, Guatemala, approche anthracologique[END_REF]. This indicates all the more the singularity of this deposit.

In the east room, several ash concentrations (Deposits #2) were spread over the floor which was also burnt [START_REF] Nondédéo | Operación III.2a: Excavaciones en el palacio XXV[END_REF]. On-floor artifacts include a fragment of a spiked censer identical to those of the central room, an obsidian blade, a flint knife, and a piece of mosaic made of polished green stone.

Each ash deposit was sampled separately. In total, 23 taxa were identified among 543 charcoal fragments. As in the central room, Sapotaceae dominate the spectrum (43 %, Figure 7.a-7.c). Other taxa include pine (Pinus sp., 31 %), Sapindaceae (12 %) including possibly canchunup (Thouinia paucidentata), craboo (Byrsonima sp., 3 %), Jamaica dogwood (Piscidia piscipula, 3 %), Moraceae including breadnut (Brosimum alicastrum, 2 %), and several minor taxa each representing less than 1 % of the charcoal: Myrtaceae, Euphorbiaceae, goncalo alves (Astronium sp.), sapote (Pouteria type), dzidzilche (Gymnopodium floribundum), several Fabaceae taxa including logwood (Haematoxylum sp.) and probably Albizia, along with some undetermined taxa. Taxa distribution is not homogeneous between these different deposits. In particular, pine is predominantly located in the north-west corner deposit. This one also contains a substantial quantity of seed remains, more precisely of endocarp fragments of a probable palm species (Arecaceae). Fragments of endocarps have also been identified in the deposit located in the door axis, this time in association with Sapindaceae charcoal. The small deposit located at the foot of the western wall presents a higher proportion of craboo. In the eastern part of the room where ashes were more dispersed, the density of macrobotanical remains was much lower and the spectrum more heterogeneous. It was marked by a higher proportion of Fabaceae taxa. Finally, the deposit located on the platform in front of the room entrance (Deposit #3) and associated with a spiked censer fragment was composed exclusively of large charcoal pieces of well-preserved Sapotaceae branches of approximately 1-2 cm in diameter (Figure 8). These could only have been produced through limited-air burning and are thus unlikely to result from an in situ open-air fire, especially as the floor was devoid of intense burning evidence. A similar deposit could have been placed in front of the central room, but it could have disappeared because of looting carried out through the structure axis.

The differences observed in the vegetal composition of the east room's ash deposit indicate that it results from at least three different fires, the first one built mainly with Sapindaceae wood, the second one with pine and the third one with craboo. There is no guarantee that these events were simultaneous. The predominance of Sapotaceae in all deposits does not indicate a link between them as these wood species were most commonly used for firewood at Naachtun (Dussol et al., 2017a). We can assume that the deposits located in the door axis are of ritual origin because of their axial position.

However, those located in the north-west corner and at the foot of the west wall could be the remains of profane fires built by squatters. We know that several decades passed between the end of activities in this sector and the time when the ritual was performed in the central room during the Early Postclassic period (1033-1254 CE). Interestingly, the three main taxa (Sapindaceae, pine and craboo) and others among those identified in the east room (dogwood, breadnut, goncalo alves and Euphorbiaceae) were all found in the central room deposit, which results from an independent fire. Without guaranteeing their contemporaneity, such a situation cannot be mere coincidence resulting from opportunistic wood gathering. The vegetal biodiversity in Neotropical regions is extremely high, which makes it unlikely to find the same set of taxa in different contexts by accident. These deposits can be the undisturbed remains of fires made simultaneously with the same wood species.

Alternatively, the remains of several fires could have been intentionally moved and mixed with each other. In all cases, it confirms the link that exists between the deposit of the central room and those of the east room.

Structure 6O-5, Río Bec Plaza

The "Río Bec" Plaza received that name because some of the architectural features of Structure 6O-4 are reminiscent of the Río Bec style. Its construction is dated to the first half of the 8 th century. Toward the end of the royalty and during the post-dynastic period (from the final Late Classic to the Terminal Classic), this was the political and ceremonial center of Naachtun, with Structure 6O-5 probably supplanting Structure 5O-5 in its political functions (Nondédéo et al., 2013b, n.d.;[START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF].

Structure 6O-5 delimits the public space to the south (Figure 2). It comprises several rooms, some of which open to the north on the plaza, while others open on Patio 28 and the Southern Complex.

Structure 6O-5 and adjacent areas were excavated between 2011 and 2013 [START_REF] Díaz | Operación II.3b: Excavaciones selectivas en el Patio 28, las Estructuras 6O-4, 6O-7 bis, 6O-5 sur, 6O-6 sur y 6O-6 ter[END_REF][START_REF] Michelet | Operación III.1: Los edificios 6O3, 6O4, 6O5 y la Plaza Río Bec[END_REF]. Some of its architectural features, such as direct access to the plaza via a large stairway and the absence of an inner bench, reproduce those of Structure 5O-5 in smaller dimensions and attest to its public function. It also played a ceremonial role as evidenced by the axial niche built in the back wall. Inside the niche, melded remains of burnt resin and pine wood chips were uncovered, likely resulting from the burning of incense (Figure 9). Whether these remains can be attributed to the regular rituals that were certainly performed in this building or to its ritual abandonment is unresolved [START_REF] Michelet | Operación III.1: Los edificios 6O3, 6O4, 6O5 y la Plaza Río Bec[END_REF]. However, a large ash and charcoal deposit (Deposit #5) was found on the intensely burnt floor just in front of the niche (Figure 4b), and this was clearly identified by radiocarbon dating as related to a post-abandonment fire (Table 3).

Just like the deposits of Structure 5O-5, this one proved to be richer in taxa than might be expected for a single fire. Eight taxa were identified among only 55 charcoal fragments: Sapotaceae (47 %), Sapindaceae (22 %, Figure 7.d, 7.e) including possibly canchunup (Thouinia paucidentata) and guaya (Exothea sp.), craboo (Byrsonima sp., 11 %), guayabillo (Myrtaceae, Myrciaria type, 7 %), pine (Pinus sp., 5 %), Mexican alvaradoa (Alvaradoa amorphoides, 5 %, Figure 7.f, 7.g) and marlberry (Ardisia sp., 2 %). A second deposit of large charcoal fragments that did not result from an in situ fire was located on the outdoor platform (Deposit #6). It was associated with spiked censer fragments, suggesting its ritual function, and contained only 13 charcoal fragments: one of Sapotaceae, the others of Mexican alvaradoa. This latter wood taxon is quite uncommon in the Naachtun charcoal record. Its presence in these two on-floor deposits suggests that they are probably part of a same set.

In sum, the sets of deposits in these two buildings distinguish themselves from the other Naachtun deposits not only by their late date but also by their atypical pattern of formation and deposition: they are associated with censer fragments and vegetal resin, probably a type of incense, and they are composed of a high number of taxa despite the fact that they result from single fires.

Tracing late fire ceremonies at Naachtun

Such deposits as those of Structures 5O-5 and 6O-5, unique in their context and composition, have never been identified in other structures of Group B. The axial position of the main deposits, the deposition of charcoal with censer shards on the platforms and the richness of the wood species burnt are elements that suggest real staging in which fire, censers and plants are intertwined. Based on Classic Maya texts and imagery, scholars have assumed that there is a symbolic link between censers and the axis mundi represented by the ceiba tree (Ceiba pentandra) [START_REF] Freidel | Maya cosmos: three thousand years on the shaman's path[END_REF][START_REF] Stuart | The fire enters his house": architecture and ritual in Classic Maya texts[END_REF][START_REF] Taube | The jade hearth: centrality, rulership, and the Classic Maya temple[END_REF]. In particular, spiked censers have been interpreted to be representations of the spiny trunk of the ceiba [START_REF] Rice | Rethinking Classic lowland Maya pottery censers[END_REF]. [START_REF] Taube | The jade hearth: centrality, rulership, and the Classic Maya temple[END_REF] showed that the association between the censer and the axis mundi is repeatedly featured in buildings and rituals, notably through the tree-censer motif. He hypothesized that the domestic hearth, traditionally placed at the center of the house, represents the world's center. In Structure 5O-5, the censers were burned together with the ritual fire components. This suggests that their role extended beyond that of simple containers for the burning of incense, and that their placement in the room center could have symbolized the domestic hearth as a locator of the world's center.

Exactly as ritual objects can hold several practical or symbolic functions in the ritual sequence, the wood burnt may have been more than simple fuel. The use of pine, for example, is well documented in pre-Hispanic and contemporary Maya societies, especially for its high flammability and fragrant smoke, which makes it a prime choice for ritual fires [START_REF] Dussol | The use of firewood in ancient Maya funerary rituals: a case study from Río Bec (Campeche, Mexico)[END_REF][START_REF] Lentz | Agroforestry and ritual at the ancient Maya center of Lamanai[END_REF][START_REF] Morehart | Wood of the gods: the ritual use of pine (Pinus spp.) by the ancient lowland Maya[END_REF]. In the case of Structures 5O-5 and 6O-5, the high number of taxa gathered in single fires seems to contradict the principle of the least effort [START_REF] Shackleton | Charcoal analysis and the "principle of least effort" -a conceptual model[END_REF]. If the only need was to provide fuel for a fire, only few different dead pieces of wood in the close woodlands would more probably have been collected. Moreover, while the predominance of Sapotaceae, craboo and pine is consistent with the usual fuel economy of the Terminal Classic Naachtun society, other wood species such as marlberry, Mexican alvaradoa, Euphorbiaceae, or those identified as possibly fustic, annatto and rosewood, were not or only occasionally used as firewood [START_REF] Dussol | Feux et forêts mayas. Usages et gestion des combustibles ligneux dans les Basses Terres centrales mayas à la période Classique : le cas du site de Naachtun, Petén, Guatemala, approche anthracologique[END_REF]Dussol et al., 2017a). This suggests that fuel supply was not the only concern when these fires were built. Some of these trees have long been used in the Yucatan Peninsula for their high-value products.

Rosewood, in particular, has been a major source of precious timber; fustic also provides timber as well as a yellow to green dye used in textile craft; annatto fruits serve as condiment in traditional cuisine and as red dye for textile [START_REF] Atran | Plants of the Petén Itza' Maya, Memoirs of the Museum of Anthropology[END_REF][START_REF] Hellmuth | Maya ethnobotany. Complete inventory. Fruits, nuts, root crops, grains, construction materials, utilitarian uses, sacred plants, sacred flowers[END_REF]. As highly valued trees, they may have had a symbolic meaning and could have been purposely burned for the occasion. Or, all these wood species (perhaps with the exception of pine that grows naturally in savannas) could have been randomly collected in the surrounding forest and burned together with the censers as a world center symbol, as if to evoke the territory and its rich vegetation [START_REF] Dussol | The use of firewood in ancient Maya funerary rituals: a case study from Río Bec (Campeche, Mexico)[END_REF]. Or even, charcoal remains from former fires could have been collected in other and perhaps remote abandoned structures and mixed with these ritual fires, explaining their high taxa richness. Such a practice could have been intended to express ancestral ties with the former Naachtun's inhabitants through the domestic hearth symbol [START_REF] Pereira | Ash, dirt, and rock: burial practices at Río Bec[END_REF]. Whatever the process and meaning, such as variety of wood species allows us to assume that there was an intentional effort to bring together multiple elements in single fires. Indeed, the ritual components may have no particular meaning when considered separately, but they might become meaningful once combined [START_REF] Bonnardin | Du matériel au spirituel : réalités archéologiques et historiques des "dépôts" de la Préhistoire à nos jours[END_REF]. Deposits #3 and #6 on the outdoor platforms stand out from this general pattern. The homogeneity of the charcoal fragments which compose them and their secondary deposition suggest that they are the remains of actual charcoal fuel produced elsewhere and used in this place to serve a specific function.

Can the incomplete censers placed in these deposits be an evocation of their role as incense burners?

Burning incense or aromatic wood chips on smoldering charcoal is an ageless practice throughout Mesoamerica and the entire world [START_REF] Niebler | Incense materials[END_REF]. No resin remains were detected in these deposits, but the combustion process may have resulted in a differential preservation of materials depending on their structure, chemical components and quantity. Although currently unverifiable, this assumption appears quite plausible and could also explain the very localized deposition or in situ combustion of large charcoal fragments in some of the household deposits (e.g. Deposits #7, #17, #19 and #20).

The symbolic meaning of these rituals clearly exceeds our understanding. But the common points shared by the deposits in these two structures lead us to believe that the ceremonies in which they originated were part of a unique event. Pagliaro and colleagues (2003) have envisaged the possibility that termination rituals could have embraced several buildings in the same site, a feature not always perceptible through limited excavations. The authors refer to contexts identified at Cerros and Blackman Eddy, Belize, or at Yaxuná, Yucatán, where fragments of the same vessel were scattered in several abandonment deposits. A similar layout was also noticed at El Palmar, Campeche, in a Terminal Classic group (Tsukamoto, 2014: 386-390). In Naachtun, a set of deposits of this nature was documented in Patio 28 in the Southern Complex, where human bones were removed from Burial 34 and dispersed in different sectors of the patio at the time of abandonment, resulting in apparently distinct abandonment deposits [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF]. This particular case confirms that some ritual practices of abandonment may have had a larger dimension than what is often perceived through single deposits, as a same event might leave multiple deposits dispersed throughout several structures [START_REF] Sion | Abandonando la casa: depósitos de última ocupación sobre pisos[END_REF].

In spite of their ritual origin, these rich spectra provide insights into past vegetation changes and help us understand the environmental context in which these ceremonies took place. The overall low proportion of Moraceae and of breadnut in particular could seem inconsistent compared with the wide distribution of these trees in the present forests and with their frequent representation in the Central Lowland pollen records. However, the socio-ecological significance of these results is difficult to assess. We know through experimentation that breadnut wood (Brosimum alicastrum) almost completely disappears during the combustion process in open-air conditions (Dussol et al., 2017b).

Consequently, it naturally leaves very few charcoal fragments compared to other wood species. On the contrary, the presence of Sapindaceae in the deposits of both Structures 5O-5 and 6O-5 is noteworthy.

Their use as firewood at Naachtun decreased progressively from the end of the Preclassic period to the Terminal Classic when they practically disappeared from the charcoal samples [START_REF] Dussol | Feux et forêts mayas. Usages et gestion des combustibles ligneux dans les Basses Terres centrales mayas à la période Classique : le cas du site de Naachtun, Petén, Guatemala, approche anthracologique[END_REF].

Nowadays, these small trees are widespread throughout the Maya Lowlands in both the seasonally flooded swamps and the upland forests, and they are among the most frequent species in the site's environment. Mentions of their uses are limited in ethnographic records to timber and firewood, excepting the species Allophylus cominia (chile chachalaca) which bears edible fruit. These trees may have been part of the wild vegetation around Naachtun during the Classic period that must have regressed as the city was growing, since agroforestry practices tend to eliminate species considered less useful [START_REF] Wiersum | From natural forest to tree crops, co-domestication of forests and tree species, an overview[END_REF]. Therefore, their resurgence in the late deposits probably reflects the return of the forest cover concomitantly to the city's abandonment and agricultural demise, which made them available again in the close environment.

Structures 5O-5 and 6O-5 are both edifices that dominated Naachtun's seat of power as materialized by the Eastern Plaza during the Late Classic, then by the Río Bec Plaza during the second part of the Late Classic and later on. Built one after the other, both of them along with their annexes are devoid of any internal arrangement such as a bench that would suggest a residential function at any time of their history. Instead, these buildings were directly accessible from public spaces that have no equivalent structure, indicating that they likely served first and foremost as primary places where rulers assembled and public ceremonies were held. The very proximity of vast residential complexes that were certainly home to Naachtun's elite members reinforces this assumption. Structure 6O-5 also regularly hosted religious ceremonies as demonstrated by the presence of the central niche, which could represent an architectural improvement compared to the former Structure 5O-5. Their analogous trajectories were concluded during the same period, after the demise of the city, through fire rituals that surprise by their commonalities. This is evidence of an institutional continuum between the two buildings, linked to the exercise of power. Although the contemporaneity of these deposits is impossible to ascertain, these late rituals performed in some of the most prestigious buildings of Naachtun's public spaces also attest to the continuity and stability of collective memory and rites [START_REF] Nondédéo | El impacto de la cobertura LiDAR en la delimitación de un sitio maya: el caso de Naachtun[END_REF]. Such ceremonies could have played a specific role in materializing the final abandonment of the city, distinct from that of the abandonment deposits usually found in houses, at a time when the site was already entering a process of reforestation.

Concluding the history, rising above the past

Historically, people have universally used rituals to invoke immaterial entities in order to control natural forces, prepare themselves for the unforeseen, reduce the impact of dramatic events and find help through bad times. In such a troubled period as the Terminal Classic, the multiplicity of ritual acts in Maya cities informs us about the way people must have lived the slow disintegration of societal and political systems. The fall of the Naachtun dynasty seems to have led to critical divergences in occupation dynamics across the city and to its progressive abandonment from approximately 800 CE (Nondédéo et al., n.d.). While the majority of residential and civic-ceremonial spaces linked to the royal family were subject to abandonment rituals, other residential complexes, particularly those surrounding the Río Bec Plaza, underwent architectural transformations related to the contraction of the remaining population (Hiquet et al., 2018, n.d.). The social-political and economic reorganization that occurred from the end of the Late Classic did not suffice, however, to pull Naachtun's society through the crises that impacted most of the Central Lowland cities towards the end of the Classic period.

The majority of the inhabitants deserted Naachtun's urban area during the 9 th and 10 th centuries. The moment of their departure was accompanied by numerous rituals performed in their houses and amidst the ruins of already abandoned neighboring houses. The presence of deposits laid on the rubble of several structures, some located just above the remains of former abandonment rituals, demonstrates how very gradual the process was [START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF]. It also highlights the importance of such actions for the people who kept in their memory the location of every deposit and went back to the ruins of their former residences to perform rituals [START_REF] Schwake | Ritual remains and collective memory: Maya examples from West Central Belize[END_REF]. Termination rituals in houses and their accesses were probably performed to mark the completion of the sedentary life cycle within the city as represented by masonry residences. The incorporation of elements such as domestic trash or ancestor bones may have symbolized the successive generations that used to live there [START_REF] Arnauld | Ritos de transición, ritos de crisis: perspectivas para la movilidad poblacional en las sociedades mayas clásicas[END_REF][START_REF] Barrientos | Los recintos funerarios y la veneración de los antepasados en los espacios habitacionales del Grupo B de Naachtun, Guatemala[END_REF].

The case of the deposits found in Structures 5O-5 and 6O-5 was probably quite different. They are the remains of ceremonies performed several decades, perhaps one or two centuries, after the cessation of activities in these buildings and the departure of the last inhabitants of Group B, at a time when the ancient political core had already been overgrown by vegetation. Therefore, these rituals cannot be considered as a way of materializing the abandonment of the buildings themselves. They rather seem to have played a role in the veneration of the buildings that used to represent the greatness of the city and of its last leaders, and would thus express some collective memory built on Naachtun's history [START_REF] Mixter | Collective remembering in archaeology: a relational approach to ancient Maya memory[END_REF][START_REF] Nondédéo | Materialidad y depósitos en Naachtun: ensayo sobre función, temporalidad y significado de los rituales mayas tardíos del periodo Clásico[END_REF]. How does this memory express itself in the ritual sequence and can it be perceptible through the archaeological record are questions that will probably remain unanswered. Despite some distinctive features (i.e. their late dating, their location in public buildings, and their association with censers and incense remains) which make these particular deposits unique in Naachtun, the limits could seem blurred between the different patterns of deposition in both the households and the public buildings. The tendency to gather various elements to build unique fires, which is visible in their rich vegetal composition, could also be reflected, although to a lesser extent, in some of the household deposits which were defined as intermediate cases (Deposits #8, #9 and #11). Moreover, it is possible that these late deposits include the remains of former fires, which would bring them closer, in terms of action and meaning, to usual termination rituals in which ashes from middens are relocated inside houses. Finally, deposits in these two structures seem to be extreme cases within an extensive range of possible deposition and formation processes of ritual deposits.

During the Late Postclassic, Colonial and Contemporary periods, people went on pilgrimage to Maya ruins even though they had probably lost all direct connection with the places they visited. This explains why offerings were mainly deposited at the foot of stelae and on decayed pyramids (e.g. [START_REF] Hansen | Forgotten structures, haunted houses, and occupied hearts: ancient perspectives and contemporary interpretations of abandoned sites and buildings in the Mirador Basin, Guatemala[END_REF][START_REF] Palka | Maya pilgrimage to ritual landscapes: insights from archaeology, history, and ethnography[END_REF]. Both are buildings that shape the landscape by their imposing dimension and strategic location [START_REF] Halperin | Ruins in pre-Columbian Maya urban landscapes[END_REF][START_REF] Walker | Cerros revisited: ceramic indicators of Terminal Classic and Postclassic settlement and pilgrimage in northern Belize[END_REF] but whose genuine political, religious or cultural significance was lost. In Naachtun, remains of deposits dated to the Late Postclassic period including Chen Mul Modeled censerswere uncovered in Group A at the top of the city's highest pyramid (Structure XX), which belongs to the time of the city's foundation at the beginning of the Early Classic period (150-300 CE) (Walker, 2013: 113;Walker and Alvarado, 2005: 137). Significant quantities of resin remains (possibly of copal incense) were also discovered in the superficial debris of other monumental buildings of Group A and C. All these deposits were certainly part of Postclassic and latter pilgrimages to the site. Conversely, we believe that the late deposits in Structures 5O-5 and 6O-5 are not the remains of pilgrimages per se, especially as they lay on the original floors of the still standing buildings. Pilgrimage rituals are characterized by repeated acts of devotion sometimes related to vestige accumulation phenomena (e.g. [START_REF] Palka | Maya pilgrimage to ritual landscapes: insights from archaeology, history, and ethnography[END_REF][START_REF] Woodfill | Ritual and trade in the Pasión-Verapaz region, Guatemala[END_REF]. The deposits in Structures 5O-5 and 6O-5 reflect instead single ceremonies that were probably held by people who were aware of the focal points of Naachtun's society before its collapse, and thus, who were probably still tied to some degree to the history of the city.

We have discovered through recent surveys that populations persisted in the area of Naachtun after the 10 th century, since a typical C-shaped Postclassic structure (dated to 950-1150 CE) was identified and excavated in Group C (Sion, 2019). No other clear Postclassic structure was evidenced in the urban area despite extensive field surveying. But this nevertheless means that it is possible that the late ceremonies were performed by people who still lived around the abandoned city. Furthermore, all successive residential abandonments were not necessarily definitive departures at the scale of the city and its surroundings (Arnauld et al., 2017b;Nondédéo et al., 2013a). Some families living near the epicenter may have gone closer to the last powerful groups established around the Río Bec Plaza, by settling in neighboring houses or reinvesting formerly abandoned places, while other families would have returned to a rural life in the hinterland (Hiquet et al., 2018, n.d.;[START_REF] Sion | La caractérisation socio-économique des élites mayas au Classique terminal (800-950/1000 apr. J.C.) : le Groupe B-Sud de Naachtun[END_REF]. This time of internal mobility or relocation within the city concomitantly to the progressive desertion of the urban area may have played a part in the preservation of the memory among the last occupants.

Living near the ruins and fallow lands is not inconsequential (Stanton and Magnoni, 2008), and the general abandonment of the Central Lowlands during the Terminal Classic certainly triggered severe identity crises among the population. The late ceremonies performed in the political buildings of Naachtun seem to express the need of the last occupants to celebrate for the last time the memory of the past glory of the city. In contrast with the termination rituals performed in households, these ceremonies would not have been the way to irrevocably prohibit entry into these particular buildings.

Instead, they would have terminated the occupation of the city and of its territory as a whole, in order to turn the page on the past before permanently leaving a region that had long been largely deserted.

Equivalent to private rituals performed in the domestic sphere, these highly ritualized activities, probably related to the departure of the final families of Naachtun, would have marked the end of a time and the beginning of a new cycle, and prevented any temporal break (Baudez, 2002: 323-330).

Conclusion

This paper deals with a little-known aspect of ancient human livelihoods, which is the way people actually lived in troubled times and went through the multi-faceted changes inherent to the perpetual cycle of rise and fall of civilizations. The long crisis that definitively transformed the Maya Lowland landscapes at the end of the first millennium gave place to multiple behaviors of mobility, revealed through an extraordinary panel of complex and diverse abandonment deposits.

The thorough examination of the material and plant composition of deposits resulting from abandonment and post-abandonment rituals in Naachtun provides an additional degree of understanding of the behaviors involved in the process of abandonment. This study allows us to put forward the institutional continuity that existed between the two political buildings 5O-5 and 6O-5, as well as the continuity of rites and the persistence of a local memory. Ritual practices participated in the construction of cultural and social identities, and ensured permanency. Between the two extremes represented by the very rich ritual fires that were lit in these buildings, and the mono-specific charcoal deposits that were placed in precise locations of some houses, the range of possible deposits is wide and could probably expand as other deposits are excavated and analyzed. Other political buildings of the site were also certainly used for ceremonies of abandonment that could have been more varied than we can imagine [START_REF] Nondédéo | Operación 5.2: la Estructura V y la cuestión funeraria[END_REF]. Some ritual acts performed in distant places may have been related with each other as suggested by the similarities between the deposits of Structures 5O-5 and 6O-5.

We argue that these late ceremonies were held by people who were still tied to the city. This allows us to advance the hypothesis that they played a role in materializing the final abandonment of Naachtun and of its territory, as they seem to have symbolically closed the buildings which had made the glory of the city and of its rulers. This study thus provides indirect evidence that human settlements persisted around the abandoned cities for some time after the collapse of Classic political systems.

Future field survey and excavations in Naachtun's hinterland based on LiDAR imagery will certainly expand our views of the dynamics of occupation and mobility at a more regional level during the postcollapse period.

Figure 1 .

 1 Figure 1. Outline of Naachtun's abandoned urban area from the final Late Classic to the Early Postclassic. Colored sectors and items indicate evidence of abandonment of settlement units (SU) and monumental units (MU) during the final Late Classic (blue), the Terminal Classic (green) and the Early Postclassic (red). J. Hiquet and J. Sion © Naachtun Archaeological Project.

Figure 2 .

 2 Figure 2. Abandonment deposits in Naachtun's Group B. Colored items indicate the location of the deposits and radiocarbon-dated middens depending on the chronological phase. J. Sion © Naachtun Archaeological Project.

Figure 3 .

 3 Figure 3. Taxa proportions in each abandonment deposit depending on the formation process (in situ burning or secondary deposits), showing two main patterns and intermediate cases. D: density of macro-botanical remains (g/L); N: number of charcoal fragments identified. L. Dussol © Naachtun Archaeological Project.

Figure 4 .

 4 Figure 4. Plans of Structure 5O-5 (a) and Structure 6O-5 (b) locating ash and charcoal deposits. Pie charts represent the taxa proportions in each deposit and sector, proportionally to sample sizes (in number (N) of charcoal fragments identified). P. Nondédéo and L. Dussol © Naachtun Archaeological Project.

Figure 5 .

 5 Figure 5. View of Deposit #1, Structure 5O-5. P. Nondédéo © Naachtun Archaeological Project.

Figure 6 .

 6 Figure 6. Rebuilt censer of Deposit #1, Structure 5O-5. M. Colín and E. Mencos © Naachtun Archaeological Project.

Figure 7 .

 7 Figure 7. Photomicrographs of charcoal fragments. a-c: Sapotaceae, Pouteria type from Deposit #1 a) transverse section x 40 showing diffuse-in-aggregate axial parenchyma and radial to oblique vessel organization; b) tangential section x 100 showing silica bodies in ray cells; c) radial sections x 200 showing large and coalescent vessel-ray pits. d-e: Sapindaceae from Deposit #5 d) transverse section

Figure 8 .

 8 Figure 8. Photography of small branches of charcoal pieces from Deposit #3. N. Bermeo © Naachtun Archaeological Project. 90 Figure 9. Macro-photography (x 3.5) of melded remains of burnt resin and wood chips (indicated by arrow) from inside the wall niche of Structure 6O-5. L. Dussol © Naachtun Archaeological Project.

Table 1 .

 1 Details of Group B deposits that underwent charcoal analysis. Density of macro-botanical remains is indicated only for flotation samples.

				Macro-
				botanical
	Dep# Nature of deposit	Location and description	remains
				density
				(g/L)
	Political buildings
	1	In situ burning	Structure 5O-5, axial hearth, central room	-
	2	In situ burning	Structure 5O-5, multiple on-floor deposits, east room	0.36
	3	Secondary deposit Structure 5O-5, exterior deposit in front of east room entrance	-
	4	In situ burning	Structure 5O-4, exterior hearth in front of back entrance	1.82
	5	In situ burning	Structure 6O-5, on-floor deposit in front of wall niche	-
	6	Secondary deposit Structure 6O-5, exterior deposit in front of entrance	-
	Households
	7	In situ burning	Patio 6, on-floor deposit in front of bench	2.73
	8	In situ burning	Patio 22, on-floor deposit inside room	0.57
	9	In situ burning	Patio 21, deposit inside bench niche	1.86
	10	Secondary deposit Patio 21, deposit inside unsealed hole	1.95
	11	In situ burning	Patio 22, on-floor deposit inside room	0.72
	12	Secondary deposit Patio 22, thick ash layer inside room	1.19
	13	Secondary deposit Patio 28, exterior on-floor deposit	0.21
	14	Secondary deposit Patio 28, exterior on-floor deposit	0.45
	15	Unclear	Patio 28, deposit inside bench niche	-
	16	Secondary deposit Patio 31, on-floor deposit in front of bench	0.01
	17	In situ burning	Patio 31, axial deposit in rubble	1.14
	18	Secondary deposit Patio 31, axial on-floor deposit	0.14
	19	Secondary deposit Patio 31, exterior deposit in unsealed hole	4.06
	20	In situ burning	Patio 32, axial deposit in rubble	2.04

Acknowledgements

The authors thank the Guatemalan Institute of Anthropology and History (IDAEH) for giving permission for fieldwork, material exportation and laboratory analysis. We thank Carlos Morales-Aguilar and Lilian Garrido, successive co-directors of the Naachtun Archaeological Project, as well as Divina Perla-Barrera, Mariana Colín and Elisa Mencos for technical and institutional help in Guatemala. We are particularly grateful to Dominique Michelet and Michelle Elliott for their mentoring throughout the study's development, to Yvonne van der Does for reviewing the English version, and to Marie-Charlotte Arnauld and two anonymous reviewers for their valuable comments that greatly improved this manuscript.

Funding sources

This study was funded by the University of Paris 1 Panthéon-Sorbonne and by the French National Center for Scientific Research (CNRS). It received the financial support of the L'Oreal-UNESCO Foundation as part of the For Women in Science Program in France (2015). The Naachtun Archaeological Project (2010-2018, dir. P. Nondédéo and L. Garrido) is part of the Center of Mexican and Central-American Studies (CEMCA-Guatemala). It was supported by the French Ministry of Foreign Affairs, the CNRS, the Pacunam Foundation, the Perenco Company, the Simone et Cino del

Taxon Common name

Deposit # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20


Dr Alexandre Vallat
email: vallat.alexandre@gmail.com

Dr Pierre Pillot

Valeur pronostique de la testostéronémie lors de l'hormonothérapie intermittente du cancer de la prostate

Keywords: Hormonothérapie intermittente, testostéronémie, résistance à la castration

Valeur pronostique de

Résumé Introduction

Le traitement du cancer de la prostate (CaP) par suppression androgénique intermittente a été proposé dans le but de diminuer les effets secondaires tout en gardant un contrôle carcinologique équivalent à un traitement continu. Par ailleurs, des études ont suggéré que le pronostic du CaP traité par suppression androgénique était corrélé à l'importance de l'effondrement de la testostéronémie.

Le but de cette étude était d'évaluer l'association entre la valeur de la testostéronémie en fin de première phase hors traitement (phase « OFF ») et le délai avant l'apparition d'une résistance à la castration.

Matériel et méthodes

Nous avons analysé de manière rétrospective 69 dossiers de patients sous traitement hormonal intermittent (THI). Le passage en phase OFF était proposé aux patients après au moins six mois d'hormonothérapie par analogue de la LH RH et un PSA<4 ng/ml. La résistance à la castration était définie selon les recommandations de l'AFU. Trois groupes de patients ont été distingués en fonction de la valeur de la testostéronémie (T) à la fin de la première phase OFF : T<0,5 ng/ml, 0,5<T<3,4 ng/ml et T>3,4 ng/ml. Les survies sans résistance à la castration, sans métastase et globale ont été comparées entre les groupes ainsi que la fréquence des complications. L'impact de la durée initiale d'hormonothérapie continue sur l'apparition d'une résistance à la castration et sur les paramètres chronologiques du THI a également été étudié.

Résultats

La testostéronémie à la fin de la première et de la 2 ème phase OFF n'était pas associée aux délais avant l'apparition d'une résistance à la castration (p=0,5), la survenue de métastase (p=0,4) et le décès (p=0,3). Elle n'était pas associée à la fréquence des complications et des effets indésirables. La durée initiale d'hormonothérapie continue n'était pas associée à l'apparition d'une résistance à la castration (p=0,6) ni à la durée moyenne des phases OFF (p=0,5) et du traitement intermittent (p=0,8).

Conclusion

Cette étude n'a pas montré d'impact de la valeur de la testostéronémie en fin de phase OFF (avant reprise de la suppression androgénique) sur les survies globales, sans Des études visant à évaluer le temps nécessaire à la normalisation de la testostérone après une phase d'hormonothérapie ont été menées montrant des variations importantes inter-patients (8) [START_REF] Yoon | Testosterone recovery after prolonged androgen suppression in patients with prostate cancer[END_REF]. La testostérone apparait donc comme une variable possiblement pronostique en raison de son implication dans la croissance tumorale et de ses variations importantes inter et intra-patient au cours du traitement intermittent. Il a par ailleurs été suggéré que la ré-ascension de testostéronémie au cours d'un traitement hormonal continu favorisait l'apparition de résistance à la castration [START_REF] Morote | Redefining clinically significant castration levels in patients with prostate cancer receiving continuous androgen deprivation therapy[END_REF]. L'objectif de cette étude était d'évaluer l'impact de la testostéronémie en fin de phase OFF sur l'évolution du cancer prostatique chez les patients sous THI. Le passage en hormonothérapie intermittente était proposé aux patients informés et après au moins six mois d'hormonothérapie bien conduite avec un PSA < 4 ng/ml, ou 1 ng/ml chez les patients en récidive après un traitement à visée curative. La reprise de l'hormonothérapie était décidée en accord avec le patient soit de manière systématique (alternance fixes de semestres ON et OFF) soit lors de l'augmentation significative du PSA avec un seuil de PSA > 10ng/ml. La résistance à la castration était définie par une augmentation du PSA sur 3 dosages successifs -avec deux augmentations de 50% au-dessus du nadir et PSA>2 ng/ml-pendant la phase ON lorsque T <0.5ng/ml ou par l'apparition de deux lésions osseuses scintigraphiques ou d'une progression mesurable selon les critères RECIST.

Matériel et méthodes

Cette

Les variations de T ont permis de définir trois groupes de patients à la fin de la première phase OFF : ceux restant castrés (T< 0,50 ng/ml), ceux ayant une T supérieure au taux de castration mais inférieure à la normale (0,5 ng/ml<T<3,4 ng/ml) et ceux normalisant leur testostéronémie (T> 3,4 ng/ml). Ces groupes ont été de même définis après la seconde phase OFF. Les progressions biologique, métastatique et la survie globale ont été calculées dans chaque groupe et comparées entre elles. L'analyse a été menée également en réduisant à deux le nombre de groupes comparés: soit castrés vs non castrés (T<0,5 ng/ml vs T>0,5 ng/ml), soit T normale vs T inférieure à la normale (T>ou=3,4 ng/ml vs T<3,4 ng/ml).

Le critère de jugement principal était l'évaluation d'une association entre la testostéronémie en fin de première phase OFF et le délai avant apparition d'une résistance à la castration. Les critères de jugement secondaires étaient :

-l'influence de la testostéronémie en fin de deuxième phase OFF sur l'apparition d'une résistance à la castration, -l'influence de la testostéronémie en fin de première et deuxième phase OFF sur la survie globale, la survie sans métastases et la survenue d'évènements cardiovasculaires, -l'impact de la durée du traitement hormonal initial sur l'apparition d'une résistance à la castration, la durée moyenne des phases OFF et sur la durée du traitement intermittent.

Les analyses statistiques ont été menées avec le logiciel XLSTAT 2017 avec l'aide d'un ingénieur bio-statisticien. Les différentes survies ont été calculées selon la méthode de Kaplan-Meier et comparées par le test du log-rank. Le test du Khi2 a été utilisé pour comparer les proportions de complications entre les différents groupes.

Résultats

Patients

Entre mai 1991 et septembre 2011, 87 dossiers de patients traités par hormonothérapie intermittente pour un CaP ont été extraits de la base de données du service. Nous avons exclu 18 dossiers : 13 étaient incomplets et 5 correspondaient à des patients qui avaient bénéficié in fine d'un traitement continu. Au total, 69 dossiers ont été analysés, comme représenté dans la figure 1. La durée médiane de suivi était de 84 mois.

Les caractéristiques des patients à l'inclusion sont résumées dans le tableau 1.

Caractéristiques carcinologiques Parmi les 69 patients, 17 (24,6%) ont présenté une résistance à la castration. La durée moyenne entre l'introduction de l'hormonothérapie et la résistance à la castration était de 59,6 mois. Parmi les 7 patients (10,1%) qui ont présenté une évolution métastatique sous traitement, aucun n'a présenté de métastases viscérales.

Le délai moyen avant l'apparition de métastase était de 67,3 mois. Les caractéristiques carcinologiques à l'inclusion sont résumées dans le tableau 2.

Traitements

Complications et effets secondaires

Mortalité globale

Au total, 39 décès ont été rapportés. La comparaison entre les 3 groupes en fonction de la testostéronémie ne retrouve pas de différence significative (log rank ; p=0,35). (Figure 3) Même constatation en ramenant à 2 groupes, soit castré vs noncastré (T<0,5 ng/ml vs T>0,5) soit T normale vs T inférieure à la normale (au seuil de 3,4 ng/ml) (respectivement p=0,73 et p=0,32). (Figure 3

Discussion

Le rôle pronostique de la testostéronémie en phase OFF d'un THI a été peu étudié. Kuo [START_REF] Kuo | Relationships between times to testosterone and prostate-specific antigen rises during the first off-treatment interval of intermittent androgen deprivation are prognostic for castration resistance in men with nonmetastatic prostate cancer[END_REF].

Evènements indésirables

Les effets indésirables de la suppression androgénique sont documentés par de nombreux rapports. La diminution de leur fréquence et de leur intensité a été l'objectif principal du THI. Ceci a été montré effectivement par de nombreuses études qui ont mis en avant l'amélioration de la qualité de vie sous THI comparativement au traitement continu. Mais ceci était essentiellement en rapport avec la diminution des bouffées de chaleur et l'amélioration de la fonction sexuelle [START_REF] Ng | The influence of testosterone suppression and recovery on sexual function in men with prostate cancer: observations from a prospective study in men undergoing intermittent androgen suppression[END_REF][START_REF] Labarta | Quality of life in patients diagnosed of prostate cancer treated with continuous androgen deprivation therapy vs. intermittent therapy[END_REF]. L'amélioration globale de la qualité de vie et la diminution des effets indésirables n'avait pas été retrouvée dans des études d'une puissance et d'une méthodologie suffisantes [START_REF] Hershman | Adverse Health Events Following Intermittent and Continuous Androgen Deprivation in Patients With Metastatic Prostate Cancer[END_REF].

Nous n'avons pas retrouvé de différence concernant les effets indésirables en fonction de la testostéronémie. Cependant la faible puissance de notre étude ne permettait pas de tirer de conclusion ferme. La surfréquence des évènements cardiovasculaires et leur intensité restent cependant controversées dans la littérature [START_REF] Nguyen | Association of androgen deprivation therapy with cardiovascular death in patients with prostate cancer: a meta-analysis of randomized trials[END_REF][START_REF] Keating | Does comorbidity influence the risk of myocardial infarction or diabetes during androgen-deprivation therapy for prostate cancer?[END_REF][START_REF] Efstathiou | Cardiovascular mortality and duration of androgen deprivation for locally advanced prostate cancer: analysis of RTOG 92-02[END_REF][START_REF] Efstathiou | Cardiovascular mortality after androgen deprivation therapy for locally advanced prostate cancer: RTOG 85-31[END_REF]. Même si le rôle bénéfique du THI dans le domaine cardio-vasculaire a été montré par certains [START_REF] Tsai | Risks of Serious Toxicities from Intermittent versus Continuous Androgen Deprivation Therapy for Advanced Prostate Cancer: A Population Based Study[END_REF], dans l'ensemble il n'est pas clairement établi (18)

Conclusion

Nous n'avons pas retrouvé d'association entre la testostéronémie à la fin de la phase OFF et la survie : globale, sans métastase et sans apparition de résistance à la castration. Il Tableau 1 : Caractéristiques des patients à l'inclusion *Question qualité de vie associée à l'IPSS Tableau 5 : Caractéristiques des patients selon les groupes de testostéronémie en fin de première phase OFF (M12) Tableau 5bis : Caractéristiques des patients selon les groupes de testostéronémie en fin de deuxième phase OFF (M24 à 36) Figure 1 : Diagramme d'inclusion et de répartition des patients selon les groupes de testostéronémie en fin de première phase OFF Figure 2 : Courbes de survie sans résistance à la castration (en mois) en fonction la testostéronémie (T< 0,50 ng/ml vs 0,5 ng/ml<T<3,4 ng/ml vs T> 3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.51) Figure 2 bis : Courbes de survie sans résistance à la castration (en mois) en fonction la testostéronémie (T<0,5 ng/ml vs T>0,5 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.75) Figure 2 ter : Courbes de survie sans résistance à la castration (en mois) en fonction la testostéronémie (T<3,4 ng/ml vs T>3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.27) Figure 3 : Courbes de survie globale (en mois) en fonction la testostéronémie (T< 0,50 ng/ml vs 0,5 ng/ml<T<3,4 ng/ml vs T> 3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.35) Figure 3 bis : Courbes de survie globale (en mois) en fonction la testostéronémie (T<0,5 ng/ml vs T>0,5 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.73) Figure 3 ter : Courbes de survie globale (en mois) en fonction la testostéronémie (T<3,4 ng/ml vs T>3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.32) Figure 4 : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T< 0,50 ng/ml vs 0,5 ng/ml<T<3,4 ng/ml vs T> 3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.44) Figure 4 bis : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T<0,5 ng/ml vs T>0,5 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.25) Figure 4 ter : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T<3,4 ng/ml vs T>3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0.26)

Apparition d'une résistance à la castration (mois)

T<3,4ng/ml T>3,4ng/ml Figure 3 : Courbes de survie globale (en mois) en fonction la testostéronémie (T< 0,50 ng/ml vs 0,5 ng/ml<T<3,4 ng/ml vs T> 3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,35) Figure 3 bis : Courbes de survie globale (en mois) en fonction la testostéronémie (T<0,5 ng/ml vs T>0,5 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,73)

Survie globale (mois)

T<3,4ng/ml T>3,4ng/ml Figure 4 : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T< 0,50 ng/ml vs 0,5 ng/ml<T<3,4 ng/ml vs T> 3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,44) Figure 4 bis : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T<0,5 ng/ml vs T>0,5 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,25)

Apparition de métastases osseuses (mois)

T<3,4ng/ml T>3,4ng/ml

  résistance à la castration et sans métastase. De même, cette valeur n'était pas associée à la fréquence des complications liées au cancer ou à la suppression androgénique. La durée initiale d'hormonothérapie continue n'était pas associée à l'apparition d'une résistance à la castration ni aux paramètres chronologiques du THI. Introduction Les schémas d'hormonothérapie intermittente du cancer de la prostate ont été établis dans l'idée d'améliorer les profils de tolérance tout en diminuant la pression de sélection sur les clones résistants à la castration. Il s'agit d'un enchainement de phases de traitement (ON) et d'arrêt du traitement (OFF). Le traitement par hormonothérapie intermittente (THI) a été confirmé dans les indications appropriées par le comité de cancérologie de l'association française d'urologie dans ses recommandations de 2018-2020 (1) en se basant sur l'étude SWOG 9346(2), 2 méta-analyses récentes (3,4) et l'essai de phase 3 ICELAND (5). Il en ressort toutefois un certain flou concernant les critères de reprise du traitement hormonal : « à l'apparition de symptômes ou d'un taux d'antigène spécifique de la prostate (PSA) supérieur à 10-20ng/ml chez le patient métastatique. ». Des modèles mathématiques d'apparition de résistance à la castration sous THI basés sur des paramètres cellulaires ont été développés (6,7). Il serait utile de définir des facteurs pronostiques utilisables en pratique clinique permettant de mieux piloter l'intermittence du traitement hormonal et de façon générale, d'identifier les patients qui seraient les meilleurs candidats au THI.

  étude a été menée de manière rétrospective monocentrique en incluant tous les hommes diagnostiqués d'un cancer de prostate entre mai 1991 et juillet 2011 traités par suppression androgénique (agoniste de la LH RH) non continue. Le rythme des consultations de surveillance était semestriel avec examen clinique et bilan biologique comportant PSA, testostéronémie (T) et créatininémie. Le choix du traitement hormonal et du type d'intermittence dépendait du praticien, des recommandations en vigueur au moment de la prescription et du patient (ses souhaits et l'intensité des effets secondaires).

  Parmi les 64 patients qui avaient bénéficié d'un traitement initial par agoniste de la LH-RH, 45 ont eu un blocage androgénique complet le 1er mois. Un patient a bénéficié d'un traitement par antagoniste de la LH-RH et 4 d'un traitement anti androgène périphérique avant relai ultérieur par agoniste de la LH-RH. Les statistiques de l'intermittence sont reportées dans le Tableau 3.

  bis et 3 ter) Evolution métastatique Sept patients ont présenté des méstastases osseuses. Là encore, il n'y avait pas de différence significative ni entre les 3 groupes (log rank ; p=0,44) ni après avoir ramené à 2 groupes avec les seuils de 0,5 ng/ml et 3,4 ng/ml (p=0,25 et p=0,26 respectivement). (Figure 4, 4 bis et 4 ter)) Fin de 2 ème phase OFF 10 Nous avons réitéré cette analyse en fin de deuxième phase OFF (soit à 24 mois pour 48 patients, à 30 mois pour 7 patients et à 36 mois pour 3 patients) avec un effectif de 58 patients restant (5 patients exclus de l'analyse pour résistance à la castration à 18 mois et 6 pour un suivi inférieur à 2 cycles d'intermittence). Treize patients ont présenté une résistance à la castration. Trente-trois décès ont été observés. Six patients ont présenté des métastases osseuses. Les mêmes analyses que celles effectuées à la fin de la 1 ère phase OFF ci-dessus n'ont pas retrouvé de différence de survie sans résistance à la castration, de survie globale ou de survie sans progression en fonction de la testostéronémie mesurée à la fin de la 2 ème phase OFF. Impact de la durée d'hormonothérapie initiale La durée d'hormonothérapie continue initiale ne semblait pas influencer l'apparition d'une résistance à la castration (p=0,6), la durée moyenne des phases OFF (p=0,5) ni la durée du traitement intermittent (p=0,8).

  n'y avait pas non plus d'association observée avec la fréquence des effets indésirables de la suppression androgénique. Même si le pilotage d'un THI par la testostéronémie plutôt que par le PSA garde un rationnel cohérent, nous n'avons pas retrouvé d'argument en faveur d'une amélioration potentielle de la survie et des effets secondaires. La durée d'hormonothérapie initiale n'était pas associée à l'apparition d'une résistance à la castration ni à la durée moyenne des phases OFF et du traitement intermittent.

Figure 1 :Figure 2 :Figure 2

 122 Figure 1 : Diagramme d'inclusion et de répartition des patients selon les groupes de testostéronémie en fin de première phase OFF

Figure 3

 3 Figure3ter : Courbes de survie globale (en mois) en fonction la testostéronémie (T<3,4 ng/ml vs T>3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,32)

Figure 4

 4 Figure4ter : Courbes de survie sans métastase (en mois) en fonction la testostéronémie (T<3,4 ng/ml vs T>3,4 ng/ml) en fin de première phase OFF. La différence entre les courbes n'est pas significative (Logrank ; p=0,26)

  Les caractéristiques des 3 groupes établis en fonction des valeurs de testostéronémie en fin de première et deuxième phases OFF ont été résumées dans le tableau 5 a et b. La tolérance à la suppression androgénique et/ou la fréquence des complications n'étaient pas significativement impactées par la testostéronémie (tableau 6).

	Fin de 1 ère phase OFF
	Résistance à la castration Après la première phase OFF, 18/69 patients avaient
	présenté une résistance à la castration. Les courbes de Kaplan-Meier comparant les survies
	Vingt-trois patients ont présenté des effets
	indésirables potentiellement imputables au traitement hormonal (bouffées de chaleur,
	douleurs abdominales, ostéoporose, gynécomastie, évènements cardiovasculaires). Vingt-
	huit patients ont présenté des complications cliniques possiblement liées à l'évolution locale

ou à distance de leur cancer (troubles fonctionnels urinaires, douleurs osseuses) qui sont reportées dans le tableau 4. en fonction des 3 groupes de testostéronémie tels que définis précédemment n'étaient pas significativement différentes (test du log rank ; p=0,51) (figure

2

). L'analyse faite après regroupement des patients en 2 sous-groupes (castrés vs non castrés soit T<0,5 ng/ml vs T>0,5 ng/ml et testostéronémie normale vs inférieure à la normale soit T<3,4 ng/ml vs T>3,4ng/ml, ne retrouvait pas non plus de différence significative (p=0,75 et p=0,27) (figures 2 bis et 2 ter).

  et al[START_REF] Morote | Redefining clinically significant castration levels in patients with prostate cancer receiving continuous androgen deprivation therapy[END_REF] avaient évalué l'impact de l'intervalle avant réascension du PSA et de la testostéronémie sur la résistance à la castration lors de la première phase OFF d'un THI chez des patients ayant un cancer de prostate M0. Dans notre étude, nous nous sommes intéressés à la valeur de la testostéronémie à l'initiation de la nouvelle phase ON et son association potentielle avec la survie ainsi que les complications et la tolérance. Cette question n'avait pas été déjà évaluée à notre connaissance. fin de la 1 ère ou de la 2 ème phase OFF. Notre cohorte comprenait des patients encore castrés au moment de la reprise de la phase ON, des patients ayant normalisés leur testostéronémie et un 3 ème contingent de patients qui avaient un taux situé dans une zone grise entre la normale et la castration. Notre hypothèse qui était que le pronostic et la tolérance au traitement pouvaient être affectés par le statut androgénique du patient à la reprise de la phase ON n'a donc pas été vérifiée.Dans le cadre du THI, plus le nombre de phases OFF augmente, plus la réascension de la testostéronémie devient lente et incomplète. Irani et al.[START_REF] Irani | Continuous versus six months a year maximal androgen blockade in the management of prostate cancer: a randomised study[END_REF] avaient montré dans leur étude randomisée cet « essoufflement » de la normalisation de la testostéronémie qui devenait substantiel à la 4 ème phase OFF. Nous n'avons pas retrouvé ce phénomène dans notre étude qui s'était limitée à l'analyse des 2 premières phases OFF.

	pratique clinique au quotidien mais ne permettait pas de tirer de conclusion spécifique à un
	sous-groupe homogène.
	Même actuellement, les durées d'interruption et de reprise de l'hormonothérapie restent
	hétérogènes, sans consensus franc. Cependant, le rôle de la testostéronémie s'est
	progressivement affirmé dans la stratégie de l'intermittence. Yoon et al. avaient mis en
	évidence la variabilité de la récupération d'une testostéronémie normale : dans leur étude,
	seulement 71,5% des hommes qui avaient eu une suppression androgénique continue
	pendant 2 ans avaient atteint un chiffre normal de testostérone après arrêt du traitement
	Les premiers patients de l'étude avaient débuté leur traitement en 1991. Les
	recommandations et les pratiques ayant constamment évolué depuis, certains patients
	n'auraient pas eu de suppression androgénique actuellement (11). Cette stratégie a permis
	cependant d'augmenter la puissance et le recul global. Par ailleurs, au cours de l'étude, la
	méthode d'intermittence de l'hormonothérapie avait varié, ce qui reflétait les variations de
	la pratique sur les 3 dernières décennies. Les limites de cette étude étaient en rapport avec
	son caractère rétrospectif et sa durée. La population hétérogène était représentative de la

L'analyse de nos résultats était limitée par le caractère rétrospectif de l'étude. Les données manquantes qui en découlent nous avaient contraint à limiter l'étude à la 1 ère et 2 ème phase OFF. Par ailleurs le caractère peu précis de la cause du décès avait empêché une analyse fiable de la survie spécifique.

Etant donnée la variabilité des dosages au fil des années dans cette étude rétrospective, nous avons décidé de ne pas considérer la testostéronémie comme une variable continue pour l'analyse mais de distinguer 3 groupes (T normale, sous le seuil de castration ou entre les deux) ce qui permettait de mieux accommoder la variabilité inhérente à la méthodologie. hormonal mais ce, au bout d'un délai médian de 22,3 mois (9). En fin de première phase OFF après un traitement hormonal initial de 6 mois, Tunn et al. observaient une normalisation de la testostéronémie dans 79,3% des cas

[START_REF] Tunn | Testosterone recovery in the off-treatment time in prostate cancer patients undergoing intermittent androgen deprivation therapy[END_REF]

. Dans l'étude de Mearini et al. la proportion était de 54% (13) et dans notre étude seulement de 23%. Cette variation substantielle qui est multifactorielle dépend du patient (en particulier l'âge) mais également de la durée de la phase ON et le délai entre l'arrêt de la suppression androgénique et la mesure de la testostéronémie.

Les modalités du THI n'ont jamais abouti à un consensus précis. La majorité des protocoles publiés se basent sur le chiffre de PSA avec un seuil variable d'arrêt et de reprise du traitement. Pourtant, étant données les variations inter-individuelles substantielles de diminution et de réascension de la testostéronémie à l'initiation et à l'arrêt des injections d'analogues de la LH-RH, le pilotage du THI en fonction de la testostéronémie pourrait être une stratégie rationnelle. Mais là aussi, des interrogations persistent quant au caractère bénéfique ou délétère de la re-stimulation des récepteurs aux androgènes par un taux circulant normal de testostérone. Nous n'avons pas mis en évidence de modification de la survie, globale, sans métastase ou sans résistance à la castration en fonction de la testostéronémie à la L'étude prospective de Kuo et al portant sur des hommes ayant un cancer de prostate M0 et traités par leuprolide pendant 9 mois avant le début de la phase OFF a évalué la cinétique de réascension du PSA et de la testostéronémie: si la survie sans apparition de résistance à la castration était associée à un délai plus long avant réascension du PSA, la cinétique de la testostérone n'avait pas d'impact indépendant

  Tableau 6 : Analyse de la fréquence des complications selon la testostéronémie.

	Tableau 1 : Caractéristiques des patients à l'inclusion Tableau 2 : Caractéristiques carcinologiques à l'inclusion Tableau 5b : Caractéristiques des patients selon les groupes de testostéronémie en fin de
	Caractéristiques La comparaison a utilisé le test du chi-2 Effectifs Moyenne Médiane Caractéristiques Effectifs Moyenne Médiane Min Min deuxième phase OFF (M24 à 36)	Max Max
	Age au diagnostic (ans)		74,8 T<0,5 ng/ml 0,5<T<3,4 ng/ml T>3,4 ng/ml 75,5 57	89
	PSA au diagnostic Effectif	Moins de 65 33 (56,9%) 8 (11%)	56,07 14 (24,1%)	24 11 (19%) 2,3	500
	65 à 75 Plus de 75 Facteurs de risque cardiovasculaires Taille (m) Poids (kg) IMC Age au diagnostic moyen <10 10 à 20 Clairance moyenne (ml/min) >20 PSAi moyen (ng/ml) Score de Gleason Nadir PSA moyen (ng/ml) ≤6 Durée jusqu'au nadir de PSA(mois) 7 (3+4) FDRCV (médiane)	27 (39%) 34(50%) 17 (24,7%) 76,3 78,7 14 (20,3%) 82 38 (55%) 0,251 24 32 (47%) 9 (13,3%) 2	1,68 76,3 25,9 2,34 75.2 58,4 23,5 6,4 0,219 23,5 2	1,68 74 25,8 2 7	71,6 70,1 23,6 0,63 14 2	1,55 57 20,5 1 6	1,85 100 34,6 5 9
		7 (4+3)	1	17 (25%) 6 (8,8%)
	Gleason	2 <6 14 (42,4%) 23 (33%) 8 14 (20,6%)	9 (64,2%)	3 (27,3%)
		3 7 8 (24,2%) 20 (29%) 9 7 (10,3%)	2 (14,3%)	5 (45,5%)
	cT	4 8 6 (18,2%) 6 (9%)	3 (21,5%)	2 (18,2%)
		5 9 5 (15,2%) 3 (4%) 1 21 (30,4%)	0	1 (9%)
	Score OMS		2		32 (46,4%)	0,25	0	0	1
	Clairance de la créatinine (ml/min)	3		16 (23,2%)	69,9	75,5	19	121,9
	IPSS N					7,2	6	0	19
	QDV*		x		52 (75,3%)	2,22	2	0	5
	*Question qualité de vie associée à l'IPSS 0	14 (20,2%)
			1		3 (4,5%)
	M
			x		7 (10,1%)
			0		54 (78,2%)
			1b		8 (11,5%)
	Traitement initial
		Chirurgie	7 (10,1%)
		Radiothérapie		3 (4,3%)
	Rattrapage				1 (1,4%)
	Nadir PSA (ng/ml)					0,32	0,17	0,05	2
	Date au Nadir(mois)					21,9	18	6	108
	Temps jusqu'à l'échappement (mois)				59,6	54	12	120
	Temps jusqu'à métastase (mois)				67,3	66	30	120
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