Professeur Patrick Pessaux
email: patrick.pessaux@chru-strasbourg.fr

PhD Fabrizio Panaro

PhD Selenia Casnedi

MD Ion Zeca

MD Ettore Marzano

MD Philippe Bachellier

MD Daniel Jaeck

PhD, FRCS Marie-Pierre P Chenard

Preliminary Results Of A Case-Control Study

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2 AIMS: To analyse the effects of the preoperative targeted molecular therapy (cetuximab (cetu) or bevacizumab (beva)) on non-tumorous liver parenchyma, and the clinical and biological outcome after liver resection for colorectal liver metastases (CLM).

METHODS:

Between January 2005 and December 2007, 36 patients receiving preoperatively cetu (n=15) or beva (n=21) were respectively matched to a control group of patients who did not receive targeted molecular therapy. They were matched on the basis of age, gender, body mass index, extent of hepatectomy, and type and number of neoadjuvant chemotherapy. Liver function tests, postoperative outcome and histopathology of the resected liver were compared.

RESULTS:

There was no mortality. Postoperative morbidity and perioperative bleeding rates were similar in both groups. In the beva group, liver function tests showed higher serum bilirubin level on postoperative day 1(POD) (p=0.001) and POD 3 (p=0.01), higher serum aspartate aminotransferase on POD 1 (p=0.004), and lower prothrombin time on POD 5 (p=0.02). In both groups, cetu and beva, the postoperative peaks of γ-glutamyl transpeptidase and alkaline phosphatase were statistically higher than in the control groups. Interestingly, the prevalence of sinusoidal injury and fibrosis were lower in patients receiving cetu (p=0.04) while the prevalence of steato-hepatitis was lower in patients receiving beva (p=0.04).

CONCLUSION:

The addition of beva or cetu to the neo-adjuvant chemotherapy regimens does not appear to increase the morbidity rates after hepatectomy for CLM.

The pathological examination did not show additional injury to the non-tumorous liver parenchyma.

Key words: hepatectomy -colorectal metastases -morbidity -hepatotoxicitytargeted molecular therapy -bevacizumab -cetuximab

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3 Hepatic resection is the only available treatment of colorectal liver metastases (CLM) allowing a 5-year survival between 25% and 44% [START_REF] Simmonds | Surgical resection of hepatic metastases from colorectal cancer: a systematic review of published studies[END_REF]. For patients with initially unresectable disease, systematic chemotherapy is offered with a goal of converting these patients to a resectable situation with similar 5-year survival rate [START_REF] Simmonds | Surgical resection of hepatic metastases from colorectal cancer: a systematic review of published studies[END_REF][START_REF] Jaeck | Bilobar colorectal liver metastases: Treatment options[END_REF].

Combined with 5-fluorouracil (5-FU), irinotecan and oxaliplatin have provided response rates exceeding 50%. In addition, the use of neoadjuvant chemotherapy has been increased particularly in patients with resectable disease [START_REF] Nordlinger | Perioperative chemotherapy with FOLFOX4 and surgery versus surgery alone for resectable liver metastases from colorectal cancer (EORTC Intergroup trial 40983): a randomised controlled trial[END_REF]. Hepatotoxic effect of oxaliplatin (4-7) and irinotecan [START_REF] Fernandez | Effect of steatohepatitis associated with irinotecan or oxaliplatin pre-treatment on resectability of hepatic colorectal metastases[END_REF][START_REF] Vauthey | Chemotherapy regimen predicts steatohepatitis and an increase in 90-day mortality after surgery for hepatic colorectal metastases[END_REF] on the nontumourous liver parenchyma has been reported. Oxaliplatin-based regimens have been associated with an increased risk of vascular lesions (sinusoidal obstruction syndrome (SOS)) (6-9) and irinotecan-containing regimens have been also associated with increased risks of steatosis and steatohepatitis (Chemotherapyassociated steato-hepatitis (CASH)) [START_REF] Fernandez | Effect of steatohepatitis associated with irinotecan or oxaliplatin pre-treatment on resectability of hepatic colorectal metastases[END_REF][START_REF] Vauthey | Chemotherapy regimen predicts steatohepatitis and an increase in 90-day mortality after surgery for hepatic colorectal metastases[END_REF]. Preliminary results demonstrated that the addition bevacizumab or cetuximab to conventional chemotherapy may further increase the response rates [START_REF] Hurwitz | Bevacizumab plus irinotecan, fluorouracil, and leucovorin for metastatic colorectal cancer[END_REF][START_REF] Cunningham | Cetuximab monotherapy and cetuximab plus irinotecan in irinotecan-refractory metastatic colorectal cancer[END_REF][START_REF] Adam | Hepatic resection after rescue cetuximab treatment for colorectal liver metastases previously refractory to conventional systemic therapy[END_REF]. Few studies reported the outcome of liver resection after use of bevacizumab in combination with chemotherapy [START_REF] D'angelica | Lack of evidence for increased operative morbidity after hepatectomy with perioperative use of bevacizumab: a matched case-control study[END_REF][START_REF] Reddy | Addition of bevacizumab to irinotecan and oxaliplatin-based preoperative chemotherapy regimens does not increase morbidity after resection of colorectal liver metastases[END_REF] and only two studies [START_REF] Ribero | Bevacizumab improves pathologic response and protects against hepatic injury in patients treated with oxaliplatin-based chemotherapy for colorectal liver metastases[END_REF][START_REF] Klinger | Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases[END_REF] reported the effect of bevacizumab on the non-tumorous liver. To our knowledge, no study has reported results with the use of cetuximab.

The aim of this study was to determine the effect of bevacizumab and cetuximab on the non-tumorous liver parenchyma and to analyse the effect of these new molecules on the postoperative outcome after hepatic resection.

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4

PATIENTS AND METHODS:

Patients:

The inclusion criteria were: hepatectomies performed for CLM, administration of neoadjuvant chemotherapy with addition of targeted molecular therapy, sufficient non-tumorous liver parenchyma for pathologic analysis, absence of underlying chronic liver disease serologically confirmed (hepatitis B or C), and no simultaneous colorectal resection. Prospective database of hepatectomy was used to identify all patients who underwent hepatic resection for CLM in our hepatobiliary surgical department. The patients who received preoperatively bevacizumab (beva) or cetuximab (cetu) were identified. To eliminate an eventual interaction between the 2 molecules, the patients who received both beva and cetu were excluded from analysis. To eliminate postoperative clinical and biological bias, patients who had radiofrequency ablation were excluded. An independent reviewer matched these patients to a control group of patients who did not receive targeted molecular therapy during the same period. They were matched on the basis of age, gender, body mass index (BMI), extent of hepatectomy (number of resected hepatic segments), and type and number of cycles of neoadjuvant chemotherapy. The control patients were taken from the prospective hepatectomy database. The number of cycles of adjuvant chemotherapy for the primary tumour was not considered. Review boards for investigations from our center approved this study.

Patients Selection for Chemotherapy:

Almost all the patients who received neoadjuvant chemotherapy were referred to our department after administration of chemotherapy. In contrast to, postoperative adjuvant chemotherapy was decided in our institution by a multidisciplinary Preoperative Evaluation:

The diagnosis of CLM was made on the basis of a raised level of tumours markers and/or after detection of liver tumours by ultrasonography, Computed tomography (CT) scan and/or MRI (Magnetic Resonance Imaging). Before liver resection, all the patients underwent a preoperative evaluation including abdominal and thoracic CT scan. Patients were considered for hepatectomy if all detected tumours could be removed completely with grossly negative surgical margins and a safe liver remnant volume. Preoperative liver functional reserve was assessed by an indocyanine green retention rate at 15 minutes (ICG-R15). In selected patients in whom the amount of future remnant liver (FRL) was considered insufficient (less than 30% of total liver volume), a preoperative portal vein embolization was performed.

Surgical Technique:

Conventional liver resection was performed through an exclusive abdominal incision.

Intraoperative ultrasound was routinely used. Extraparenchymal control of ipsilateral inflow and outflow was attempted before resection whenever possible. The hepatic pedicle was then dissected and lymph nodes in the hepatoduodenal ligament were analyzed.

Liver transection was performed using an ultrasonic dissector. Vascular clamping was not performed routinely but if necessary resections were performed preferentially under intermittent portal triad clamping. Liver resection was achieved with a macroscopic tumour free margin of ≥1 cm whenever possible. Postoperative parameters of hepatic injury, including prothrombin time, bilirubin, transaminase levels (aspartate aminotransferase and alanine aminotransferase), γglutamyl transpeptidase and alkaline phosphatase were measured on postoperative days (POD) 1, 3, 5, and 7. Routine chest X-rays were systematically performed on POD 3 and 7. CT-scan with intravenous contrast was carried out on any patient with a suspected intra-abdominal or pleural collection. Patients were reviewed 4 to 6 weeks after operation to complete the follow-up.

Definitions:

Major hepatectomies were defined as the resection of three or more segments.

Mortality and morbidity were defined as death or complication occurring either within 30 days following surgery or during the hospital stay. Complications were stratified in accordance with Dindo's classification [START_REF] Dindo | Classification of surgical complications: A new proposal with evaluation in a cohort of 6336 patients and results of a survey[END_REF]. Pulmonary, urinary, cardiac, renal and thrombo-embolism complications were grouped in medical complication. Surgical complication included wound infection, intraabdominal collection, hemorrhage, biliary fistula and liver failure. Liver failure was defined as the simultaneous presence of a prothrombin time <50% and a serum bilirubin >50µmol/L (or >29mg/L) on postoperative day 5 (the "50-50" criteria) [START_REF] Balzan | The "50-50 criteria" on postoperative day 5: An accurate predictor of liver failure and death after hepatectomy[END_REF].

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Postoperative hemoglobin loss was calculated with a validated mathematical model [START_REF] Ozier | French Study Group on blood transfusion in liver transplantation. Institutional variabiliby in transfusion practice for liver transplantation[END_REF].

Pathologic Analysis:

All slides, which were originally prepared from formalin-fixed and paraffinembedded tissue, were reviewed. Representative slides of nontumorous hepatic tissue located as far as possible from the tumour were selected for the study. The morphologic analyses were performed using slides stained with hematoxylin-eosin, Masson trichrome, and reticulin stain. The slides were examined by a consensus of 2 pathologists with hepatobiliary expertise (S.C. and M-P.C.), who were both unaware of the clinical data. Hepatic steatosis was graded from 0 to 3: grade 0, absent; 1, mild (steatosis < 30%); 2, moderate (30% <= steatosis < 60%); 3, severe (60% <=steatosis). Steatohepatitis was graded as defined by Kleiner et al. [START_REF] Kleiner | Design and validation of a histological scoring system for non-alcoholic fatty liver disease[END_REF] (absence, borderline, presence) based on steatosis (score 0≤5%; score 1=5% to 33%; score 2=33% to 66%; and score 3≥66%), Lobular inflammation (score 0=no foci; score 1≤ two foci; score 2=two to for foci; and score 3≥ four foci per X200 field), and ballooning (score 0=none; score 1=few balloon cells; score 2=many cells/prominent ballooning). SOS which was characterized by sinusoidal dilatation, hepatocellular atrophy, and centrilobular or perisinusoidal fibrosis was graded according to the Rubbia-Brandt's classification recently reported (4). In detail, the SOS was classified as follows 0=absent; grade 1=mild (centrilobular involvement limited to one-third of the lobule); grade 2=moderate (centrilobular involvement extending to two-thirds of the lobule); grade 3=severe (complete lobular involvement). Fibrosis was subdivided in perisinusoidal, portal, and associated The two groups were comparable concerning the characteristics of CLM, preoperative assessment, and type of surgery (Table 2). The control groups had higher rate of extrahepatic procedures without statistical significance. The only difference observed was the size of the largest CLM: 57±22 mm in the group cetu versus 38±26 in the control group (p=0.02) and 29±13 mm in the group beva versus 57±27 mm in the control group (p=0.001).

Postoperative outcome:

There was no postoperative mortality. There were no intraoperative complications.

There was no difference concerning morbidity rate between the different groups (Table 3). In the group cetu, major complications involved formation of a biliary fistula associated with deep abscess requiring radiologic percutaneous drainage. No hepatic neither renal failure was reported. Three patients in the beva group developed wound infections. The mean blood loss trended to be higher in the cetu and beva groups, without statistical significance. This difference was essentially due to 1 patient in each group. In the group cetu, 1 patient had a blood loss of 3500 ml with 8 packed red blood cells transfused, and in the group beva 1 patient had a blood loss of 4100 ml with 9 packed red blood cells transfused. There was no difference in the length of hospitalization.

Laboratory results:

The significative results were summarised in the table 4. There was no difference between the groups concerning all laboratory tests on preoperative day. In both group, the peaks of the enzymes of cholestasis (γ-glutamyl transpeptidase and alkaline phosphatase) were higher than in the control groups. There was no other difference in the cetu group. However in the beva group the prothrombin time was lower on the POD 5 (p=0.02), the serum bilirubin level was higher on the POD 1

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11 (p=0.001) and POD 3 (p=0.01), and serum aspartate aminotransferase was higher on the POD 1 (p=0.004).

Histological results:

Pathological review of the non-tumorous liver parenchyma revealed that the prevalence of SOS and fibrosis was significantly lower in patients receiving cetu than those treated without cetu (table 5). The prevalence of steato-hepatitis was significantly lower in patients receiving beva than those treated without beva (Table 5).

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12

DISCUSSION:

In this case-control study, there was no consequence on the non-tumorous liver parenchyma and on the outcome after hepatic resection for CLM in patients who received targeted molecular therapy. Although not randomized, one of the strong point in this study is that it is a case-control study with prospective data collection.

The prospective nature of the study allows for more complete data collection. The different arms were matched on the main factors influencing quality of the hepatic parenchyma and outcome after hepatic resection: age, gender, body mass index (BMI), extent of hepatectomy (number of resected hepatic segments), and type and number of cycles of neoadjuvant chemotherapy.

Analysis of the different groups:

The groups were comparable excepting for the mean number of lines of preoperative chemotherapy and the size of the largest lesion which were higher in the cetu group. The size of the largest CLM is a prognostic factor for survival [START_REF] Nordlinger | Surgical resection of colorectal carcinoma metastases to the liver: a prognostic scoring system to improve case selection based on 1568 patients[END_REF][START_REF] Fong | Clinical score for predicting recurrence after hepatic resection for metastatic colorectal cancer: Analysis of 1001 consecutive cases[END_REF] but does not induce modification of the remnant non-tumorous hepatic parenchyma neither on the postoperative outcome. This variable represents an easy way to evaluate the chemotherapy response and therefore is not a bias in this series. Indeed, the major variables which may influence on the postoperative outcome were matched. The difference of number of lines could be explained, by the fact that beva is a first-line therapy, while cetu is considered as second-line drug. Cetu is mostly administered to patients who are non-responder at the first-line chemotherapy regimen. This difference of number of lines is not a bias because the groups were matched concerning the type and number of cycles of neoadjuvant chemotherapy.

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Postoperative outcome: Hepatic resection has become the standard of care for selected patients with CLM.

During the last years, systemic chemotherapy for colorectal cancer has greatly improved. In fact, recently, the introduction of cetu and beva to the standard chemotherapy has further improved survival. The safety of major hepatic resection in the setting of neo-adjuvant chemotherapy is crucial and still unknown when considering the use of these new "targeted molecules" [START_REF] Adam | Hepatic resection after rescue cetuximab treatment for colorectal liver metastases previously refractory to conventional systemic therapy[END_REF][START_REF] D'angelica | Lack of evidence for increased operative morbidity after hepatectomy with perioperative use of bevacizumab: a matched case-control study[END_REF][START_REF] Reddy | Addition of bevacizumab to irinotecan and oxaliplatin-based preoperative chemotherapy regimens does not increase morbidity after resection of colorectal liver metastases[END_REF][START_REF] Ribero | Bevacizumab improves pathologic response and protects against hepatic injury in patients treated with oxaliplatin-based chemotherapy for colorectal liver metastases[END_REF][START_REF] Klinger | Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases[END_REF]. This case-control study did not show any deleterious consequences on outcomes after hepatic resection when cetu or beva were added to the standard chemotherapy regimen. Surgical complications such as bile leaks (n=2) and intra-abdominal collection requiring percutaneous radiological drainage (n=2) were observed in the cetu group, but these differences did not reach significance. The postoperative complication rate among patients receiving beva in our series was similar to that observed in other reports [START_REF] Reddy | Addition of bevacizumab to irinotecan and oxaliplatin-based preoperative chemotherapy regimens does not increase morbidity after resection of colorectal liver metastases[END_REF]. In particular, no patient developed hepatic failure. In the literature, several studies reported no increase of morbidity and mortality after preoperative chemotherapy [START_REF] Parc | Preoperative systemic 5-fluorouracil does not increase the risk of liver resection[END_REF][START_REF] Parikh | Perioperative complications in patients undergoing major liver resection with or without neoadjuvant chemotherapy[END_REF][START_REF] Scoggins | Preoperative chemotherapy does not increase morbidity or mortality of hepatic resection for colorectal cancer metastases[END_REF]. In the series of Aloia et al. [START_REF] Aloia | Liver histology and surgical outcomes after pre-operative chemotherapy with fluorouracil plus oxaliplatin in colorectal cancer liver metastases[END_REF], patients who had received more than 12 cycles of preoperative chemotherapy had higher risk of reoperation and a longer hospital stay. Another report by Karoui et al [START_REF] Karoui | Influence of chemotherapy on the risk of major hepatectomy for colorectal liver metastases[END_REF] showed that administration of more than 6 cycles of neoadjuvant systemic chemotherapy increased morbidity after major liver resection but did not increase mortality. All the patients included in our study received more than 8 cycles of chemotherapy (oxaliplatin and/or irinotecan) and so were at high risk of developing postoperative complication. Vauthey et al. [START_REF] Vauthey | Chemotherapy regimen predicts steatohepatitis and an increase in 90-day mortality after surgery for hepatic colorectal metastases[END_REF] were the only authors who reported an increased 90day mortality after liver surgery due to presence of steatohepatitis correlated with neoadjuvant irinotecan administration. Few papers focused on assessing the

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14 influence of preoperative beva on complication after hepatic resection [START_REF] D'angelica | Lack of evidence for increased operative morbidity after hepatectomy with perioperative use of bevacizumab: a matched case-control study[END_REF][START_REF] Reddy | Addition of bevacizumab to irinotecan and oxaliplatin-based preoperative chemotherapy regimens does not increase morbidity after resection of colorectal liver metastases[END_REF][START_REF] Ribero | Bevacizumab improves pathologic response and protects against hepatic injury in patients treated with oxaliplatin-based chemotherapy for colorectal liver metastases[END_REF][START_REF] Klinger | Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases[END_REF]. There were no differences in overall, severe, hepatic, and bleeding complications in group of patients treated with beva. There was also a trend toward of an increase risk of wound infection but the occurrence of this complication did not reach a statistical significance, as reported in our series. To our knowledge, our study reported for the first time, the outcome after hepatic resection in patients treated with neoadjuvant cetu.

Laboratory analysis:

As expected, the level of enzymes of cholestasis increased after POD 3 in all groups. However, the peaks were higher in the cetu and beva groups than in the control groups. As well known, the rise of both alkaline phosphatase and γ-glutamyl transpeptidase after liver hepatectomy has been reported as biological indicators of hepatic regeneration [START_REF] Suc | Natural history of hepatectomy[END_REF]. Hypothetically, targeted molecules do not have repercussion on the hepatic regeneration. However, in beva group, the AST level was higher on the POD 1, serum bilirubin level was higher at the POD 1 and 3, and prothrombin time was lower at the POD 5, compared to the control group. These last results may be reflecting a transitory hepatocellular dysfunction but without clinical relevance.

Histological analysis:

Furthermore, the pathological examination did not show additional injury to the non-tumorous liver parenchyma. In contrast, in the non-tumorous liver parenchyma the prevalence of SOS and fibrosis was higher in patients treated without cetu, while the prevalence of steatohepatitis was higher in patients treated without beva,

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15 respectively to those observed in the two case-control groups. These pathological findings may be a consequence of a "protective effect" of the targeted molecular therapy as previously reported by the MD Anderson group [START_REF] Ribero | Bevacizumab improves pathologic response and protects against hepatic injury in patients treated with oxaliplatin-based chemotherapy for colorectal liver metastases[END_REF]. Klinger et al. [START_REF] Klinger | Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases[END_REF] reported that beva decreased the severity of high grade SOS (grade 3). No study has analysed specific hepatotoxicity with the use of cetu. In the literature, Adam et al. [START_REF] Adam | Hepatic resection after rescue cetuximab treatment for colorectal liver metastases previously refractory to conventional systemic therapy[END_REF] reported 16% of steatosis and 20% of vascular injury in the non-tumorous parenchyma in patients treated with cetu. However, histopathologic features directly related to treatment with cetu were not identified because most of patients were treated with several line of chemotherapy.

Correlation between the cumulative dose of chemotherapy and the presence or histological injury

Considering that SOS is mostly related to oxaliplatin therapy, the longer delay observed between the last dose administrated and surgery in the group cetu could be interpreted as a bias. The SOS injury may improve spontaneously with the time.

However, this hypothesis has not been proven. In contrast, the sinusoidal lesions and fibrosis may persist for several months after chemotherapy has been discontinued (>4 years) and in some cases could progress considerably [START_REF] Rubbia-Brandt | Severe hepatic sinusoidal obstruction associated with oxaliplatin-based chemotherapy in patients with metastatic colorectal cancer[END_REF][START_REF] Rubbia-Brandt | Sinusoidal obstruction syndrome is a major feature of hepatic lesions associated with oxaliplatin neoadjuvant chemotherapy for liver colorectal metastases[END_REF].

However, the number of patients receiving adjuvant chemotherapy for the primary tumour was similar between the different groups avoiding this bias. There was also no correlation between the cumulative dose of oxaliplatin and the presence or severity of SOS [START_REF] Zorzi | Chemotherapy-associated hepatotoxicity and surgery for colorectal liver metastases[END_REF]. The effect of the delay between the last dose of chemotherapy and the liver surgery on postoperative morbidity and mortality was analysed by Welsh et al. [START_REF] Welsh | Safe liver resection following chemotherapy for colorectal metastases is a matter of timing[END_REF]. These authors reported for the first time that surgical complication rate decreased when the interval between chemotherapy and surgery increased (>4

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weeks). In our series, the delay between the last dose of chemotherapy and the liver surgery was similar in the different groups.

Conclusions:

In conclusion, addition of cetu or beva to the based neoadjuvant chemotherapy regimens does not appear to increase the morbidity rates of the hepatic resection for CLM. Furthermore, there was no additional injury to the nontumorous liver parenchyma.

  E P T E Dcommittee including oncologists, pathologists, gastroenterologists, radiologists, and surgeons.

6

 6 All patients received antibiotic prophylaxis (cefazolin) and a daily subcutaneous injection of sodium low-molecular-weight heparin as deep venous thrombosis prophylaxis.Data collections and postoperative follow-up:Patients were seen by a physician daily, until hospital discharge. The patients were monitored for postoperative complication, mortality, and postoperative course.

  M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT8 perisinusoidal and portal[START_REF] Kleiner | Design and validation of a histological scoring system for non-alcoholic fatty liver disease[END_REF][START_REF] Brunt | Grading and staging the histopathological lesions of chronic hepatitis: the Knodell histology activity index and beyond[END_REF]. The presence of regenerative nodular hyperplasia was recorded.Statistical Analysis:Quantitative data were expressed as a mean ± standard errors of mean. A two-group comparison was performed by the Chi 2 test with Fisher exact test correlation or the Mann-Whitney U test. A result was considered statistically significant if p < 0.05. All statistical analyses were performed using SPSS (Version 13.0, Chicago, IL). M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 9 RESULTS: Patient demographics: From January 2005 to December 2007, a total of 246 patients underwent hepatectomy for CLM in our department. Among these 246 patients, 148 patients received neoadjuvant chemotherapy. Of these patients, 15 received preoperatively cetu and 21 received preoperatively beva. The mean number of cycles of cetu and beva were respectively 12.8+/-9.9 (ranges: 3-38) and 8.1+/-4.7 (ranges: 3-17). Only 1 patient in each group received 3 cycles of targeted molecular therapies, the others patients received more than 6 cycles. Control matched groups were compared with these patients and the characteristics of the different groups were summarized in the table 1. The number of patient receiving adjuvant chemotherapy for the primary tumour was similar between the different groups: 5 patients in the group cetu (Fluorouracil and Folinic acid: n=2 and FOLFOX: n=3) versus 4 patients in the group control (Fluorouracil and Folinic acid: n=1 and FOLFOX: n=3) and 8 patients in the group beva (Fluorouracil and Folinic acid: n=2 and FOLFOX: n=6) versus 5 patients in the group control (FOLFOX: n=5). The only differences reported were the mean line of preoperative chemotherapy and the mean interval of time between last dose of oxaliplatin and surgery: the number of lines and the delay were higher in the group cetu (respectively p=0.003 and p=0.04) The mean time interval between administration of cetu and beva and the date of surgery was respectively 10±5.2 weeks (range: 4-14) and 11.7±4.7 weeks (range: 5-20). In the group cetu, 10 patients received irinotecan and 5 patients received oxaliplatin. In the group beva, 16 patients received irinotecan, 2 patients received oxaliplatin, and 3 patients received irinotecan and oxaliplatin. CLM and procedure: M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 10

TABLE 1 :

 1 Clinical and pathologic features of patients

		Cetu	Control	p	Beva	Control	p
		n=15	group 1		n=21	group 2
			n=15			n=21
	Gender			0.38			0.53
	Male	13	10		10	13
	Female	2	5		11	8
	Age (years)	58.8±12.3 60.4±9.6	0.98	65±8.2	63.3±11.7 0.63
	BMI (mean)	26.1±4.6	26±6.2	0.44	26±7	26.9±5	0.65
	BMI>25 (n)	7	8	0.99	7	11	0.34
	BMI>30 (n)	2	2	0.99	5	3	0.69
	ASA			0.09			0.99
	1-2	11	15		21	21
	3-4	4	0		0	0
	Associated medical
	condition:
	Artery hypertension	0	4	0.09	3	8	0.15
	Diabetes Mellitus	4	4	0.99	2	2	0.99
	Chronic pulmonary	2	0	0.48	0	2	0.48
	disease
	Coronaropathy	1	4	0.32	1	2	0.9
	Renal insufficiency	0	0	0.99	0	1	0.9
	Site of primary tumour			0.71			0.1
	Colon	7	9		17	11
	Rectum	8	6		4	10
	Status of primary lymph			0.99			0.16
	nodes
	Positive	11	11		13	18
	Negative	4	4		8	3
	Adjuvant chemotherapy for	5	4	0.99	8	5	0.45
	the primary tumour
	Mean line of preoperative	2.2±1	1.1±0.4	0.003	1.2±0.5	1.2±0.4	0.9
	chemotherapy
	Mean number of cycles of	18.6±18.1 11.7±5.8	0.42	8.8±5	10.4±6.5	0.35
	preoperative chemotherapy
	Mean number of cycles of	10.8±6.6	12	0.63	5.8±2.5	8.7±3	0.08
	preoperative oxaliplatin
	Mean number of cycles of	22.1±7.9	12	0.08	8.3±4.6	8.2±2.9	0.94
	preoperative irinotecan
	Mean interval time between	8.4±3.6	7±4.2	0.68	7.7±3.1	7.6±3.9	0.88
	last dose of chemotherapy
	and surgery (weeks)
	Mean interval time between	23.6±3.5 11.7±11.2 0.04	7.9±5.1	11.7±7.4	0.22
	last dose of oxaliplatin and
	surgery (weeks)
	Mean interval time between	10±5.2	8±4.9	0.35	8.7±4.4	10.6±7.5	0.35
	last dose of irinotecan and
	surgery (weeks)

TABLE 2 :

 2 Characteristics of the hepatic metastases and procedure

		Cetu	Control	p	Beva	Control	p
		n=15	group 1		n=21	group 2
			n=15			n=21
	Synchronous hepatic			0.69			0.32
	metastases	9	11		12	16
	Hepatic metastases			0.48			0.32
	Single	2	0		5	9
	Multiple	13	15		16	12
	Mean number of lesion	5.6±3.6	4.3±3	0.41	3.8±2.5	3±3	0.12
	Size of the largest	57±22	38±26	0.02	29±13	57±27	0.001
	metastases (mm)
	Preoperative portal vein	3	0	0.22	4	2	0.66
	embolization
	Preoperative ICG-R15 (%)	8.5±4.3	8.6±3.7	0.85	9.2±4.3	8.7±2.7	0.84
	Hepatectomy			0.69			0.99
	Anatomic	9	11		12	13
	Non-anatomic	6	4		9	8
	Hepatectomy			0.45			0.9
	Major	7	5		5	4
	Minor	8	10		16	17
	Mean number of resected	3±1.1	3±1.5	0.99	2.4±1	2.4±1.5	0.99
	segment
	Mean weight of resected	438±175 316±208	0.07	236±154 239±163	0.9
	specimen (g)
	Intermittent portal triad	4	0	0.09	7	2	0.13
	clamping
	Associated extrahepatic	7	2	0.1	5	3	0.69
	procedure
	ICG=Indocyanine green retention rate at 15 minutes

TABLE 3 :

 3 Postoperative outcome

		Cetu	Control	p	Beva	Control	p
		n=15	group 1		n=21	group 2
			n=15			n=21
	Length of procedure (min)	385±147	307±97	0.41	321±160	277±55	0.66
	Blood loss (ml)	1452±2018 766±551 0.16 983±1476 548±233 0.38
	Perioperative blood	6	2	0.21	7	3	0.27
	transfusion
	Mean of number of PRBCs	7±2.7	4	0.18	4.4±2.3	2±1.6	0.3
	transfused
	Intensive care unit	2	0	0.48	1	2	0.9
	Overall morbidity*	7	2	0.10	6	4	0.71
	Medical complications*	5	2	0.38	5	4	0.90
	Surgical complications*	3	0	0.22	3	0	0.23
	Grade I
	Wound infection	0	0	0.99	3	0	0.23
	Grade II
	Urinary tract	0	0	0.99	1	2	0.9
	infection
	Pulmonary	5	2	0.38	3	2	0.9
	complications
	Pneumonia	2	2	0.99	1	2	0.9
	Pleural effusion	2	0	0.48	2	0	0.48
	Pulmonary	1	0	0.90	0	0	0.99
	embolism
	Grade III
	Biliary fistula	2	0	0.48	0	0	0.99
	Intraabdominal	2	0	0.48	0	0	0.99
	collection requiring
	percutaneous drainage
	Reintervention	0	0	0.99	0	0	0.99
	Grade IV
	Liver failure	0	0	0.99	0	0	0.99
	Mortality (Grade V)	0	0	0.99	0	0	0.99
	Length of hospitalization	16.3±8.1	12.9±2.6 0.72	12.7±6.3 13.7±4.2 0.11
	(days)
	*: Some patients had more than one complication.
	PRBCs =packed red blood cells

TABLE 4 :

 4 Results of postoperative liver function

		Cetu	Control	p	Beva	Control	p
		n=15	group 1		n=21	group 2
			n=15			n=21
	Prothrombin time (%)
	Day 5	71.9±13.1	70.7±8.4	NS	71.8±7.7	81.7±17.4	0.02
	Serum bilirubin (µmol/L)
	Day 1	23.6±2.7	14.6±3.9	NS	82.2±239.4	14.7±4.1	0.001
	Day 3	21.7±7.8	15.9±5.9	NS	21.9±13.8	13.7±4.1	0.01
	Serum aspartate
	aminotransferase (U/L)
	Day 1	525±507	373±199	NS	415±217	239±146	0.004
	γ-glutamyl transpeptidase
	(U/L)
	Day 3	149±120	68±46	0.02	106±51	43±13	<0.001
	Day 5	269±156	115±118	0.005	214±140	85±42	0.0002
	Day 7	372±278	175±109	0.01	350±213	188±99	0.003
	Alkaline phosphatase (U/L)
	Day 3	130±58	88±61	NS	104±30	69±21	0.001
	Day 5	244±189	152±185	NS	194±77	98±32	<0.001
	Day 7	398±313	163±93	0.01	323±166	174±81	0.007
	NS=no significant

TABLE 5 :

 5 Histological results

		Cetu	Control	p	Beva	Control	p
		n=15	group 1		n=21	group 2
			n=15			n=21
	Steatosis	5	6	0.99	3	8	0.15
	<30%	3	4		3	3
	30% -60%	2	2		0	4
	>60%	0	0		0	1
	Steatohepatitis	2	2	0.99	1	7	0.04
	Borderline	2	0		1	3
	Presence	0	2		0	4
	SOS	0	5	0.04	3	5	0.69
	Grade 1	0	0		1	1
	Grade 2	0	5		2	4
	Fibrosis	0	5	0.04	3	4	0.9
	Perisinusoidal	0	4		1	4
	Portal	0	1		1	0
	Perisinusoidal and portal	0	0		1	0
	RNH	0	2	0.48	5	2	0.4
	SOS= sinusoidal obstruction syndrome
	RNH=regenerative nodular hyperplasia