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Klondike (solitaire)

Klondike, also known as Canfield, is a card game for one player and the best known and most popular version of the patience or solitaire family, as well as one of the most challenging in widespread play. It has spawned numerous variants including Batsford, Easthaven, King Albert, Thumb and Pouch, Somerset or Usk and Whitehead, as well as the American variants of the games, Agnes and Westcliff. The distinguishing feature of all variants is a triangular layout of the tableau, building in ascending sequence and packing in descending order.

Name
In the U.S. and Canada, it is so well known that the term "Solitaire", in the absence of qualifiers, typically refers to Klondike. Equally in the UK, it is often just known as "Patience". Elsewhere the game is known as American Patience.

Historically Klondike was also called Canfield in America, perhaps because it was a casino game at the Canfield Casino in Saratoga Springs, New York, and this is the name by which it became known in England. Today, however, Canfield is more usually the American name for the patience game called "Demon" in England, which is a different game altogether. Likewise the rumour prevails that this other game was devised by Richard Canfield even though Canfield himself called his game "Klondike".

History
The origins of the name Klondike are unknown; a handful of authors have speculated the name derives from the late 19th-century Klondike Gold Rush, but no material evidence substantiates such a claim. The earliest rules for the game known as Klondike today appear in the 1907 edition of Hoyle's Games under the name "Seven-Card Klondike". Hoyles calls it a simpler version of "Klondike", also described in the same book, but which turns out to be a gambling version of the game nowadays known as Canfield in the US and Demon elsewhere in the world.

In the 1913 edition of the so-called Official Rules of Card Games, Seven-Card Klondike has become Klondike, with the modification that the pack is run through one card at a time instead of three, and the original Klondike is now being called Canfield.

Klondike's inclusion in Microsoft Windows in the 1990s contributed significantly to its current popularity. It is considered the most popular version of solitaire.

Rules
Klondike is played with a standard 52-card deck, without Jokers.

After shuffling, a tableau of seven fanned piles of cards is laid from left to right. From left to right, each pile contains one more card than the last. The first and left-most pile contains a single upturned card, the second pile contains two cards, and so forth. The topmost card of each pile is turned face up.

The remaining cards form the stock and are placed facedown at the upper left of the layout.

The four foundations (light rectangles in the upper right of the figure) are built up by suit from Ace (low in this game) to King, and the tableau piles can be built down by alternate colors. Every face-up card in a partial pile, or a complete pile, can be moved, as a unit, to another tableau pile on the basis of its highest card. Any empty piles can be filled with a King, or a pile of cards with a King. The aim of the game is to build up four stacks of cards starting with Ace and ending with King, all of the same suit, on one of the four foundations, at which time the player would have won.

There are different ways of dealing the remainder of the deck from the stock to the waste, including the following:
 * Turning three cards at once to the waste, with no limit on passes through the deck.
 * Turning three cards at once to the waste, with three passes through the deck.
 * Turning one card at a time to the waste, with three passes through the deck.
 * Turning one card at a time to the waste with only a single pass through the deck and playing it if possible.
 * Turning one card at a time to the waste, with no limit on passes through the deck.

If the player can no longer make any meaningful moves, the game is considered lost. At this point, winning is impossible.

Probability of winning
The probability of being able to win a game of Klondike with best-possible play is not known, although Hoyle's Rules of Games suggests the chances of winning as being 1 in 30 games. The inability of theoreticians to precisely calculate these odds has been referred to by mathematician Persi Diaconis as "one of the embarrassments of applied probability". The best information about the winnability of Klondike concerns a modified version of the game called "Thoughtful Solitaire" or "Thoughtful Klondike", in which the location of all 52 cards is known. The probability of winning Thoughtful Klondike (with draw three rules) has been calculated as being approximately 82%, more precisely as having a confidence interval of 81.956% ± 0.096%. Thoughtful Klondike is not quite the same as simply playing with all cards face up, as this would allow an impossible movement of a pile if the top downturned card happened to be in sequence with the upturned card underneath it. Using physical cards, Thoughtful Klondike can be played by peeking at the face-down cards or by dealing the downturned cards face-up but sideways to differentiate them from the tableau piles. With electronic programs Thoughtful Klondike can be played by allowing unlimited use of undos to return to the start if a choice turns out to be unfavorable. Because the only difference between the two games (regular and thoughtful) is the knowledge of card location, all winnable Thoughtful Klondike games will also be winnable in regular Klondike. The win percentage of 82% for Thoughtful Klondike gives an upper bound of 82% on the win percentage of regular Klondike when the location of all cards is unknown. The true probability with best play might be much smaller, because the difference between a right and wrong move cannot be known in advance whenever more than one move is possible, and some cards are still hidden. Ultimately, very little is known about the winnability of regular Klondike. A Klondike-playing AI using Monte Carlo tree search was able to solve up to 35% of randomly generated regular Klondike games, placing a lower bound on the winnability percentage. One experiment found a skilled player could win 189 out of 442 games (43%), but this gives a discrepancy of almost 40% between regular and Thoughtful Klondike.

Single deck
Below are some single-pack variants of Klondike:
 * Agnes (US variant): the stock is dealt in batches of seven on reserve piles and every one is available. Furthermore, the bases of the foundations depend on the twenty-ninth card, which is dealt on the foundations.
 * Easthaven (less commonly Aces Up,) twenty-one cards are dealt into seven piles of three, two face-down and one face-up. A space in this game may only be filled by a king or sequence starting with a king (several rule sets simplify this and allow any card or sequence to be moved to a vacancy), and when a play goes to a standstill, seven new cards are dealt to the tableau, one top of each pile. Easthaven may be played with 2 or 3 decks. The two-deck version is either called Double Easthaven or Gypsy.
 * Nine Across: nine columns of cards are dealt, as opposed to seven in classic Klondike. The player can choose which cards to form the foundations; if one or more eights are exposed, for example, the player may decide to build on eights, and the piles are built up 8-9-10-J-Q-K-Ace-2-3-4-5-6-7. If eights are built on, sevens fill up spaces and so forth. The stock is dealt through one by one as many times as required.
 * Somerset or Usk: as Klondike but all the cards are dealt out: 10 in the first row, 9 in the second, and so on until there are 3 in the last.
 * Thumb and Pouch: a card in the tableau can be built upon another that is any suit other than its own (e.g. spades cannot be placed over spades) and spaces can be filled by any card or sequence.
 * Whitehead: all cards are dealt face up, building is by color (red on red, black on black), a sequence made up of cards that are of the same suit can be moved as a unit, and a space can be filled by any card or sequence.
 * Westcliff (US variant): thirty cards are dealt into ten piles of three cards, two face down and one face up. A space in this game can be filled with any card or sequence.
 * Kuipers: as Klondike but with eight columns instead of seven, turning one card at a time to the waste, with no limit on passes through the deck. This lowers the probability of winning to approximately 5%.

Gambling variant
In some casinos, Klondike is turned into a gambling game, by playing with the rule of dealing cards one at a time and going through the stock once. For example, a player would pay $50 to play, and the house would pay $5 for each card played to the foundations. This form of Klondike is sometimes called Las Vegas Solitaire.

Joker Solitaire
Joker Solitaire is a variant of Klondike created by Joli Quentin Kansil which adds two jokers that serve as limited wild cards. This adds more skill because players are required to make many calculated decisions.

Double Solitaire
Klondike has been turned into a two-player game under the name Double Solitaire. Players have their own packs and may not play to each other's tableaus but share their foundations. Players take turns until they are unable to play a card from their talons. The first player to play all 52 cards is the winner. Informally, "Double" Solitaire can be played as a party game with more than 2 players.

Computerized versions
Digital versions of Klondike have helped popularize the game and offer advantages over playing with a physical deck. Notable examples of computerized versions include:
 * A software version of Klondike named simply Solitaire has been a regular inclusion in the Microsoft Windows operating system, beginning with Windows 3.0 in 1990. Initially Microsoft included the game as both a diversion and a teaching tool: for many users, Solitaire was their first introduction to using a computer mouse.  Microsoft officials stated in 1994 that "for years, Solitaire was the most-used application for Windows".
 * In 1981, the Atari Program Exchange published Mark Reid's implementation of Klondike for Atari 8-bit computers, simply titled Solitaire.
 * Michael A. Casteel's shareware version of Klondike for the Macintosh was first released in 1984, and has been continually updated since.
 * Klondike was added to Clubhouse Games: 51 Worldwide Classics for Nintendo Switch, a compilation of tabletop games.

Scoring in the Microsoft Windows Solitaire version of Klondike is as follows:

Moving cards directly from the Waste stack to a Foundation scores 10 points. However, if the card is first moved to a Tableau, and then to a Foundation, an extra 5 points are scored making a total of 15. Thus, to score the most points, no cards should be moved directly from the Waste to Foundation.

Time also plays a role, if the 'Timed game' option is selected. In this case, 2 points are deducted every 10 seconds. Bonus points are scored using the formula 700,000 ÷ (seconds to finish), if the game takes at least 30 seconds. If the game takes under 30 seconds, no bonus points are awarded.

Literature

 * Arnold, Peter (2011). Card Games for One. Chambers.
 * Coops, Helen Leslie (1939). 100 Games of Solitaire. Whitman. 128 pp.
 * Morehead, Albert and Geoffrey Mott-Smith (2001). The Complete Book of Solitaire and Patience. Foulsham, Slough.

title: Klondike (solitaire)


text:
Edna Ferber

Edna Ferber (August 15, 1885 – April 16, 1968) was an American novelist, short story writer and playwright. Her novels include the Pulitzer Prize-winning So Big (1924), Show Boat (1926; made into the celebrated 1927 musical), Cimarron (1930; adapted into the 1931 film which won the Academy Award for Best Picture), Giant (1952; made into the 1956 film of the same name) and Ice Palace (1958), which also received a film adaptation in 1960. She helped adapt her short story "Old Man Minick", published in 1922, into a play (Minick) and it was thrice adapted to film, in 1925 as the silent film Welcome Home, in 1932 as The Expert, and in 1939 as No Place to Go.

Early years
Ferber was born August 15, 1885, in Kalamazoo, Michigan, to a Hungarian-born Jewish storekeeper, Jacob Charles Ferber, and his Milwaukee, Wisconsin-born wife, Julia (Neumann) Ferber, who was of German Jewish descent. The Ferbers had moved to Kalamazoo from Chicago, Illinois in order to open a dry goods store, and her older sister Fannie was born there three years earlier. Ferber's father was not adept at business, and the family moved often during Ferber's childhood. From Kalamazoo, they returned to Chicago for a year, and then moved to Ottumwa, Iowa where they resided from 1890 to 1897 (ages 5 to 12 for Ferber). In Ottumwa, Ferber and her family faced brutal anti-Semitism, including adult males verbally abusing, mocking and spitting on her on days when she brought lunch to her father, often mocking her in a Yiddish accent. According to Ferber, her years in Ottumwa "must be held accountable for anything in me that is hostile toward the world.". During this time, Ferber's father began to lose his eyesight, necessitating costly and ultimately unsuccessful treatments. At the age of 12, Ferber and her family moved to Appleton, Wisconsin, where she graduated from high school and later briefly attended Lawrence University.

Career
After graduation, Ferber planned to study elocution, with vague thoughts of someday becoming an actor, but her family could not afford to send her to college. On the spur of the moment, she took a job as a cub reporter at the Appleton Daily Crescent and subsequently moved to the Milwaukee Journal. In early 1909 Ferber suffered a bout of anemia and returned to Appleton to recuperate. She never resumed her career as a reporter, although she subsequently covered the 1920 Republican National Convention and 1920 Democratic National Convention for the United Press Association.

While Ferber was recovering, she began writing and selling short stories to various magazines, and in 1911 she published her first novel, Dawn O'Hara, The Girl Who Laughed. In 1912, a collection of her short stories was published in a volume entitled Buttered Side Down. In her autobiography, Ferber wrote: "In that day, and for a girl in her early twenties, they were rather hard tough stories... The book got good reviews. I was startled and grimly pleased when some of the reviewers said that obviously these stories had been written by a man who had taken a feminine nom de plume as a hoax. I have always thought that a writing style should be impossible of sex determination; I don't think the reader should be able to say whether a book has been written by a man or a woman."

In 1925, she won the Pulitzer Prize for her book So Big. Ferber initially believed her draft of what would become So Big lacked a plot, glorified failure, and had a subtle theme that could easily be overlooked. When she sent the book to her usual publisher, Doubleday, she was surprised to learn that he greatly enjoyed the novel. This was reflected by the several hundreds of thousands of copies of the novel sold to the public. Following the award, the novel was made into a silent film starring Colleen Moore that same year. A remake followed in 1932, starring Barbara Stanwyck and George Brent, with Bette Davis in a supporting role. A 1953 version of So Big starring Jane Wyman is the most popular version to modern audiences.

Riding the popularity of So Big, Ferber's next novel, Show Boat, was just as successful. Shortly after its release, composer Jerome Kern proposed turning it into a musical. Ferber was shocked, thinking it would be transformed into a typical light entertainment of the 1920s. It was not until Kern explained that he and Oscar Hammerstein II wanted to create a different type of musical that Ferber granted him the rights and it premiered on Broadway in 1927, and has been revived 8 times.

Her 1952 novel, Giant, became the basis of the 1956 movie, starring Elizabeth Taylor, James Dean and Rock Hudson.

Death
Ferber died at her home in New York City, of stomach cancer, at the age of 82. She left her estate to her sister and nieces.

Personal life
Ferber never married, had no children, and is not known to have engaged in a romance or sexual relationship. In her early novel Dawn O'Hara, the title character's aunt remarks, "Being an old maid was a great deal like death by drowning – a really delightful sensation when you ceased struggling." Ferber did take a maternal interest in the career of her niece Janet Fox, an actress who performed in the original Broadway casts of Ferber's plays Dinner at Eight (1932) and Stage Door (1936).

Ferber was known for being outspoken and having a quick wit. On one occasion, she led other Jewish guests in leaving a house party after learning the host was antisemitic. Once, after Noel Coward joked about how her suit made her resemble a man, she replied, "So does yours."

Importance of Jewish identity
Starting in 1922, Ferber began to visit Europe once or twice annually for thirteen or fourteen years. During this time and unlike most Americans, she became troubled by the rise of the Nazi Party and its spreading of the antisemitic prejudice she had faced in her childhood. She commented on this saying, "It was a fearful thing to see a continent – a civilization – crumbling before one's eyes. It was a rapid and seemingly inevitable process to which no one paid any particular attention." Her fears greatly influenced her work, which often featured themes of racial and cultural discrimination. Her 1938 autobiography, A Peculiar Treasure, originally included a spiteful dedication to Adolf Hitler which stated: "To Adolf Hitler, who has made me a better Jew and a more understanding human being, as he has of millions of other Jews, this book is dedicated in loathing and contempt."While this was changed by the time of the book's publication, it still alluded to the Nazi threat. She frequently mentions Jewish success in her book, alluding to and wanting to show not just that Jewish success, but Jews being able to use that and prevail.

Algonquin Round Table
Ferber was a member of the Algonquin Round Table, a group of wits who met for lunch every day at the Algonquin Hotel in New York. Ferber and another member of the Round Table, Alexander Woollcott, were long-time enemies, their antipathy lasting until Woollcott's death in 1943, although Howard Teichmann states in his biography of Woollcott that their feud was due to a misunderstanding. According to Teichmann, Ferber once described Woollcott as "a New Jersey Nero who has mistaken his pinafore for a toga".

Ferber collaborated with Round Table member George S. Kaufman on several plays presented on Broadway: Minick (1924), The Royal Family (1927), Dinner At Eight (1932), The Land Is Bright (1941), Stage Door (1936), and Bravo! (1948).

Political views
In a poll carried out by the Saturday Review of Literature, asking American writers which presidential candidate they supported in the 1940 election, Ferber endorsed Franklin D. Roosevelt.

Characteristics of works
Ferber's novels generally featured strong female protagonists, along with a rich and diverse collection of supporting characters. She usually highlighted at least one strong secondary character who faced discrimination, ethnic or otherwise.

Ferber's works often concerned small subsets of American culture, and sometimes took place in exotic locations she had visited but was not intimately familiar with, such as Texas or Alaska. She thus helped to highlight the diversity of American culture to those who did not have the opportunity to experience it. Some novels are set in places she had not visited.

Legacy

 * Ferber was portrayed by the actress Lili Taylor in the film Mrs. Parker and the Vicious Circle (1994).
 * In 2008, The Library of America selected Ferber's article "Miss Ferber Views 'Vultures' at Trial" for inclusion in its two-century retrospective of American True Crime.
 * On July 29, 2002, in her hometown of Appleton, Wisconsin, the U.S. Postal Service issued an 83¢ Distinguished Americans series postage stamp honoring her. Artist Mark Summers, well known for his scratchboard technique, created this portrait for the stamp referencing a black-and-white photograph of Ferber taken in 1927.
 * A fictionalized version of Edna Ferber appears briefly as a character in Philipp Meyer's novel The Son (2013).
 * An additional fictionalized version of Edna Ferber, with her as the protagonist, appears in a series of mystery novels by Ed Ifkovic and published by Poisoned Pen Press, including Downtown Strut: An Edna Ferber Mystery, written in 2013.
 * In 2013, Ferber was inducted into the Chicago Literary Hall of Fame.
 * In her hometown of Appleton, Wisconsin, the Edna Ferber Elementary School was named after her. Construction of the school was initially voted down in a 1971 referendum.

List of works
Ferber wrote thirteen novels, two autobiographies, numerous short stories, and nine plays, many which were written in collaborations with other playwrights.

Novels

 * Dawn O'Hara, The Girl Who Laughed (1911)
 * Fanny Herself (1917)
 * The Girls (1921)
 * So Big (1924) (won Pulitzer Prize)
 * Show Boat (1926, Grosset & Dunlap)
 * Cimarron (1930)
 * American Beauty (1931)
 * Come and Get It (1935)
 * Saratoga Trunk (1941)
 * Great Son (1945)
 * Giant (1952)
 * Ice Palace (1958)
 * Ice Palace (1958)

Novellas and short story collections

 * Buttered Side Down (1912)
 * Roast Beef, Medium (1913) Emma McChesney stories
 * Personality Plus (1914) Emma McChesney stories
 * Emma Mc Chesney and Co. (1915) Emma McChesney stories
 * Cheerful – By Request (1918)
 * Half Portions (1919)
 * Gigolo (1922)
 * Mother Knows Best (1927)
 * They Brought Their Women (1933)
 * Nobody's in Town: Two Short Novels (1938) Contains Nobody's in Town and Trees Die at the Top
 * One Basket: Thirty-One Short Stories (1947) Includes "No Room at the Inn: A Story of Christmas in the World Today"

Autobiographies

 * A Peculiar Treasure (1939)
 * A Kind of Magic (1963)

Plays

 * Our Mrs. McChesney (1915) (play, with George V. Hobart)
 * $1200 a Year: A Comedy in Three Acts (1920) (play, with Newman Levy)
 * Minick: A Play (1924) (play, with G. S. Kaufman), adapted from her short story "Old Man Minick"
 * The Royal Family (1927) (play, with G. S. Kaufman)
 * Dinner at Eight (1932) (play, with G. S. Kaufman)
 * Stage Door (1936) (play, with G.S. Kaufman)
 * The Land Is Bright (1941) (play, with G. S. Kaufman)
 * Bravo! (1949) (play, with G. S. Kaufman)

Screenplays

 * Saratoga Trunk (1945) (film, with Casey Robinson)

Musical adaptations

 * Show Boat (1927) – music by Jerome Kern, lyrics and book by Oscar Hammerstein II, produced by Florenz Ziegfeld
 * Saratoga (1959) – music by Harold Arlen, lyrics by Johnny Mercer, dramatized by Morton DaCosta
 * Giant (2009) – music and lyrics by Michael John LaChiusa, book by Sybille Pearson

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Edna Ferber


text:
Brain tumor

A brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant (cancerous) tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and secondary tumors, which most commonly have spread from tumors located outside the brain, known as brain metastasis tumors. All types of brain tumors may produce symptoms that vary depending on the size of the tumor and the part of the brain that is involved. Where symptoms exist, they may include headaches, seizures, problems with vision, vomiting and mental changes. Other symptoms may include difficulty walking, speaking, with sensations, or unconsciousness.

The cause of most brain tumors is unknown, though up to 4% of brain cancers may be caused by CT scan radiation. Uncommon risk factors include exposure to vinyl chloride, Epstein–Barr virus, ionizing radiation, and inherited syndromes such as neurofibromatosis, tuberous sclerosis, and von Hippel-Lindau Disease. Studies on mobile phone exposure have not shown a clear risk. The most common types of primary tumors in adults are meningiomas (usually benign) and astrocytomas such as glioblastomas. In children, the most common type is a malignant medulloblastoma. Diagnosis is usually by medical examination along with computed tomography (CT) or magnetic resonance imaging (MRI). The result is then often confirmed by a biopsy. Based on the findings, the tumors are divided into different grades of severity.

Treatment may include some combination of surgery, radiation therapy and chemotherapy. If seizures occur, anticonvulsant medication may be needed. Dexamethasone and furosemide are medications that may be used to decrease swelling around the tumor. Some tumors grow gradually, requiring only monitoring and possibly needing no further intervention. Treatments that use a person's immune system are being studied. Outcomes for malignant tumors vary considerably depending on the type of tumor and how far it has spread at diagnosis. Although benign tumors only grow in one area, they may still be life-threatening depending on their size and location. Malignant glioblastomas usually have very poor outcomes, while benign meningiomas usually have good outcomes. The average five-year survival rate for all (malignant) brain cancers in the United States is 33%.

Secondary, or metastatic, brain tumors are about four times as common as primary brain tumors, with about half of metastases coming from lung cancer. Primary brain tumors occur in around 250,000 people a year globally, and make up less than 2% of cancers. In children younger than 15, brain tumors are second only to acute lymphoblastic leukemia as the most common form of cancer. In NSW Australia in 2005, the average lifetime economic cost of a case of brain cancer was AU$1.9 million, the greatest of any type of cancer.

Signs and symptoms
The signs and symptoms of brain tumors are broad. People may experience symptoms regardless of whether the tumor is benign (not cancerous) or cancerous. Primary and secondary brain tumors present with similar symptoms, depending on the location, size, and rate of growth of the tumor. For example, larger tumors in the frontal lobe can cause changes in the ability to think. However, a smaller tumor in an area such as Wernicke's area (small area responsible for language comprehension) can result in a greater loss of function.

Headaches
Headaches as a result of raised intracranial pressure can be an early symptom of brain cancer. However, isolated headache without other symptoms is rare, and other symptoms including visual abnormalities may occur before headaches become common. Certain warning signs for headache exist which make the headache more likely to be associated with brain cancer. These are defined as "abnormal neurological examination, headache worsened by Valsalva maneuver, headache causing awakening from sleep, new headache in the older population, progressively worsening headache, atypical headache features, or patients who do not fulfill the strict definition of migraine". Other associated signs are headaches that are worse in the morning or that subside after vomiting.

Location-specific symptoms
The brain is divided into lobes and each lobe or area has its own function. A tumor in any of these lobes may affect the area's performance. The symptoms experienced are often linked to the location of the tumor, but each person may experience something different.
 * Frontal lobe: Tumors may contribute to poor reasoning, inappropriate social behavior, personality changes, poor planning, lower inhibition, and decreased production of speech (Broca's area).
 * Temporal lobe: Tumors in this lobe may contribute to poor memory, loss of hearing, and difficulty in language comprehension (Wernicke's area is located in this lobe).
 * Parietal lobe: Tumors here may result in poor interpretation of languages, difficulty with speaking, writing, drawing, naming, and recognizing, and poor spatial and visual perception.
 * Occipital lobe: Damage to this lobe may result in poor vision or loss of vision.
 * Cerebellum: Tumors in this area may cause poor balance, muscle movement, and posture.
 * Brain stem: Tumors on the brainstem can cause seizures, endocrine problems, respiratory changes, visual changes, headaches and partial paralysis.

Behavior changes
A person's personality may be altered due to the tumor-damaging lobes of the brain. Since the frontal, temporal, and parietal lobes control inhibition, emotions, mood, judgement, reasoning, and behavior, a tumor in those regions can cause inappropriate social behavior, temper tantrums, laughing at things which merit no laughter, and even psychological symptoms such as depression and anxiety. More research is needed into the effectiveness and safety of medication for depression in people with brain tumors.

Personality changes can have damaging effects such as unemployment, unstable relationships, and a lack of control.

Cause
The best known cause of brain cancers is ionizing radiation. Approximately 4% of brain cancers in the general population are caused by CT scan radiation. For brain cancers that follow a CT scan at lags of 2 years or more, it has been estimated that 40% are attributable to CT scan radiation. The relationship between ionizing radiation and brain cancers can be best explained by radiation carcinogenesis, and traditional models of oncogenesis. The stochastic effects of ionizing radiation demonstrate a dose-response relationship to the probability of occurrence, but no dose-response relationship to severity of disease. The majority of radiation-induced brain cancers are caused by ionizing radiation from medical sources such as CT scans.

Mutations and deletions of tumor suppressor genes, such as P53, are thought to be the cause of some forms of brain tumor. Inherited conditions, such as Von Hippel–Lindau disease, tuberous sclerosis, multiple endocrine neoplasia, and neurofibromatosis type 2 carry a high risk for the development of brain tumors. People with celiac disease have a slightly increased risk of developing brain tumors. Smoking has been suggested to increase the risk but evidence remains unclear.

Although studies have not shown any link between cell phone or mobile phone radiation and the occurrence of brain tumors, the World Health Organization has classified mobile phone radiation on the IARC scale into Group 2B – possibly carcinogenic. The claim that cell phone usage may cause brain cancer is likely based on epidemiological studies which observed a slight increase in glioma risk among heavy users of wireless phones. When those studies were conducted, GSM (2G) phones were in use. Modern, third-generation (3G) phones emit, on average, about 1% of the energy emitted by those GSM (2G) phones, and therefore the finding of an association between cell phone usage and increased risk of brain cancer is not based upon current phone usage.

Meninges
Human brains are surrounded by a system of connective tissue membranes called meninges that separate the brain from the skull. This three-layered covering is composed of (from the outside in) the dura mater, arachnoid mater, and pia mater. The arachnoid and pia are physically connected and thus often considered as a single layer, the leptomeninges. Between the arachnoid mater and the pia mater is the subarachnoid space which contains cerebrospinal fluid (CSF). This fluid circulates in the narrow spaces between cells and through the cavities in the brain called ventricles, to support and protect the brain tissue. Blood vessels enter the central nervous system through the perivascular space above the pia mater. The cells in the blood vessel walls are joined tightly, forming the blood–brain barrier which protects the brain from toxins that might enter through the blood.

Tumors of the meninges are meningiomas and are often benign. Though not technically a tumor of brain tissue, they are often considered brain tumors since they protrude into the space where the brain is, causing symptoms. Since they are usually slow-growing tumors, meningiomas can be quite large by the time symptoms appear.

Brain matter
The brains of humans and other vertebrates are composed of very soft tissue and have a gelatin-like texture. Living brain tissue has a pink tint in color on the outside (gray matter), and nearly complete white on the inside (white matter), with subtle variations in color. The three largest divisions of the brain are:
 * Cerebral cortex
 * Brainstem
 * Cerebellum

These areas are composed of two broad classes of cells: neurons and glia. These two types are equally numerous in the brain as a whole, although glial cells outnumber neurons roughly 4 to 1 in the cerebral cortex. Glia come in several types, which perform a number of critical functions, including structural support, metabolic support, insulation, and guidance of development. Primary tumors of the glial cells are called gliomas and often are malignant by the time they are diagnosed.

The thalamus and hypothalamus are major divisions of the diencephalon, with the pituitary gland and pineal gland attached at the bottom; tumors of the pituitary and pineal gland are often benign.

The brainstem lies between the large cerebral cortex and the spinal cord. It is divided into the midbrain, pons, and medulla oblongata.

Spinal cord
The spinal cord is considered a part of the central nervous system. It is made up of the same cells as the brain: neurons and glial cells.

Diagnosis

Although there is no specific or singular symptom or sign, the presence of a combination of symptoms and the lack of corresponding indications of other causes can be an indicator for investigation towards the possibility of a brain tumor. Brain tumors have similar characteristics and obstacles when it comes to diagnosis and therapy with tumors located elsewhere in the body. However, they create specific issues that follow closely to the properties of the organ they are in.

The diagnosis will often start by taking a medical history noting medical antecedents, and current symptoms. Clinical and laboratory investigations will serve to exclude infections as the cause of the symptoms. Examinations in this stage may include the eyes, otolaryngological (or ENT) and electrophysiological exams. The use of electroencephalography (EEG) often plays a role in the diagnosis of brain tumors.

Brain tumors, when compared to tumors in other areas of the body, pose a challenge for diagnosis. Commonly, radioactive tracers are uptaken in large volumes in tumors due to the high activity of tumor cells, allowing for radioactive imaging of the tumor. However, most of the brain is separated from the blood by the blood–brain barrier (BBB), a membrane that exerts a strict control over what substances are allowed to pass into the brain. Therefore, many tracers that may reach tumors in other areas of the body easily would be unable to reach brain tumors until there was a disruption of the BBB by the tumor. Disruption of the BBB is well imaged via MRI or CT scan, and is therefore regarded as the main diagnostic indicator for malignant gliomas, meningiomas, and brain metastases.

Swelling or obstruction of the passage of cerebrospinal fluid (CSF) from the brain may cause (early) signs of increased intracranial pressure which translates clinically into headaches, vomiting, or an altered state of consciousness, and in children changes to the diameter of the skull and bulging of the fontanelles. More complex symptoms such as endocrine dysfunctions should alarm doctors not to exclude brain tumors.

A bilateral temporal visual field defect (due to compression of the optic chiasm) or dilation of the pupil, and the occurrence of either slowly evolving or the sudden onset of focal neurologic symptoms, such as cognitive and behavioral impairment (including impaired judgment, memory loss, lack of recognition, spatial orientation disorders), personality or emotional changes, hemiparesis, hypoesthesia, aphasia, ataxia, visual field impairment, impaired sense of smell, impaired hearing, facial paralysis, double vision, or more severe symptoms such as tremors, paralysis on one side of the body hemiplegia, or (epileptic) seizures in a patient with a negative history for epilepsy, should raise the possibility of a brain tumor.

Imaging
Medical imaging plays a central role in the diagnosis of brain tumors. Early imaging methods – invasive and sometimes dangerous – such as pneumoencephalography and cerebral angiography have been abandoned in favor of non-invasive, high-resolution techniques, especially magnetic resonance imaging (MRI) and computed tomography (CT) scans, though MRI is typically the reference standard used. Neoplasms will often show as differently colored masses (also referred to as processes) in CT or MRI results.
 * Benign brain tumors often show up as hypodense (darker than brain tissue) mass lesions on CT scans. On MRI, they appear either hypodense or isointense (same intensity as brain tissue) on T1-weighted scans, or hyperintense (brighter than brain tissue) on T2-weighted MRI, although the appearance is variable.
 * Contrast agent uptake, sometimes in characteristic patterns, can be demonstrated on either CT or MRI scans in most malignant primary and metastatic brain tumors.
 * Pressure areas where the brain tissue has been compressed by a tumor also appear hyperintense on T2-weighted scans and might indicate the presence of a diffuse neoplasm due to an unclear outline. Swelling around the tumor known as peritumoral edema can also show a similar result. This is because these tumors disrupt the normal functioning of the BBB and lead to an increase in its permeability.

More recently, advancements have been made to increase the utility of MRI in providing physiological data that can help to inform diagnosis and prognosis. MRI itself is sufficient in identifying the brain tumor's location and morphology, but other types of MRI may be used on top of that, such as MRA, MRS, pMRI, fMRI, and DWI. These imaging techniques help doctors and surgeons to diagnose the type of tumor, plan for surgery, and to assess treatment and radiation/chemotherapy. Treatment with radiation and chemotherapy can lead to treatment induced changes in the brain, visible on conventional imaging and which can be difficult to differentiate from tumor recurrence.

Different Types of MRI Scans
Magnetic Resonance Angiography (MRA) – looks at the blood vessels in the brain. In the diagnosis of brain tumor, MRAs are typically carried out before surgery to help surgeons get a better understanding of the tumor vasculature. For example, a study was done where surgeons were able to separate benign brain tumors from malignant ones by analyzing the shapes of the blood vessels that were extracted from MRA. Although not required, some MRA may inject contrast agent, gadolinium, into the patient to get an enhanced image

Magnetic Resonance Spectroscopy (MRS) – measures the metabolic changes or chemical changes inside the tumor. The most common MRS is proton spectroscopy with its frequency measured in parts per million (ppm). Gliomas or malignant brain tumors have different spectra from normal brain tissue in that they have greater choline levels and lower N-acetyl aspartate (NAA) signals. Using MRS in brain tumor diagnosis can help doctors identify the type of tumor and its aggressiveness. For example, benign brain tumors or meningioma have increased alanine levels. It can also help to distinguish brain tumors from scar tissues or dead tissues caused by previous radiation treatment, which does not have increased choline levels that brain tumors have, and from tumor-mimicking lesions such as abscesses or infarcts.

Perfusion Magnetic Resonance Imaging (pMRI) – assess the blood volume and blood flow of different parts of the brain and brain tumors. pMRI requires the injection of contrast agent, usually gadopentetate dimeglumine (Gd-DTPA) into the veins in order to enhance the contrast. pMRI provides a cerebral blood volume map that shows the tumor vascularity and angiogenesis. Brain tumors would require a larger blood supply and thus, would show a high cerebral blood volume on the pMRI map. The vascular morphology and degree of angiogenesis from pMRI help to determine the grade and malignancy of brain tumors. For brain tumor diagnosis, pMRI is useful in determining the best site to perform biopsy and to help reduce sampling error. pMRI is also valuable for after treatment to determine if the abnormal area is a remaining tumor or a scar tissue. For patients that are undergoing anti-angiogenesis cancer therapy, pMRI can give the doctors a better sense of efficacy of the treatment by monitoring tumor cerebral blood volume.

Functional MRI (fMRI) – measures blood flow changes in active parts of the brain while the patient is performing tasks and provides specific locations of the brain that are responsible for certain functions. Before performing a brain tumor surgery on patients, neurosurgeons would use fMRI to avoid damage to structures of the brain that correspond with important brain functions while resecting the tumor at the same time. Preoperative fMRI is important because it is often difficult to distinguish the anatomy near the tumor as it distorts its surrounding regions. Neurosurgeons would use fMRI to plan whether to perform a resection where tumor is surgically removed as much as possible, a biopsy where they take a surgical sampling amount to provide a diagnosis, or to not undergo surgery at all. For example, a neurosurgeon may be opposed to resecting a tumor near the motor cortex as that would affect the patient's movements. Without preoperative fMRI, the neurosurgeon would have to perform an awake-craniotomy where the patient would have to interact during open surgery to see if tumor removal would affect important brain functions.

Diffusion Weighted Imaging (DWI) – a form of MRI that measures random Brownian motion of water molecules along a magnetic field gradient. For brain tumor diagnosis, measurement of apparent diffusion coefficient (ADC) in brain tumors allow doctors to categorize tumor type. Most brain tumors have higher ADC than normal brain tissues and doctors can match the observed ADC of the patient's brain tumor with a list of accepted ADC to identify tumor type. DWI is also useful for treatment and therapy purposes where changes in diffusion can be analyzed in response to drug, radiation, or gene therapy. Successful response results in apoptosis and increase in diffusion while failed treatment results in unchanged diffusion values.

Other Types of Imaging Techniques
Computed Tomography (CT) Scan – uses x-rays to take pictures from different angles and computer processing to combine the pictures into a 3D image. A CT scan usually serves as an alternative to MRI in cases where the patient cannot have an MRI due to claustrophobia or pacemaker. Compared to MRI, a CT scan shows a more detailed image of the bone structures near the tumor and can be used to measure the tumor's size. Like an MRI, a contrast dye may also be injected into the veins or ingested by mouth before a CT scan to better outline any tumors that may be present. CT scans use contrast materials that are iodine-based and barium sulfate compounds. The downside of using CT scans as opposed to MRI is that some brain tumors do not show up well on CT scans because some intra-axial masses are faint and resemble normal brain tissue. In some scenarios, brain tumors in CT scans may be mistaken for infarction, infection, and demyelination. To suspect that an intra-axial mass is a brain tumor instead of other possibilities, there must be unexplained calcifications in the brain, preservation of the cortex, and disproportionate mass effect.

CT Angiography (CTA) – provides information about the blood vessels in the brain using X-rays. A contrast agent is always required to be injected into the patient in the CT scanner. CTA serves as an alternative to MRA.

Positron Emission Tomography (PET) Scan – uses radioactive substances, with the most common one being a sugar known as FDG, while more specific tracers for glioma are emerging. This injected substance is taken up by cells that are actively dividing. Tumor cells are more active in dividing so they would absorb more of the radioactive substance. After injection, a scanner would be used to create an image of the radioactive areas in the brain. PET scans are used more often for high-grade tumors than for low-grade tumors. It is useful after treatment to help doctors determine if the abnormal area on an MRI image is a remaining tumor or a scar tissue. Scar tissues will not show up on PET scans while tumors would.

However, these techniques cannot alone diagnose high- versus low-grade gliomas, and thus the definitive diagnosis of brain tumor should only be confirmed by histological examination of tumor tissue samples obtained either by means of brain biopsy or open surgery. The histological examination is essential for determining the appropriate treatment and the correct prognosis. This examination, performed by a pathologist, typically has three stages: interoperative examination of fresh tissue, preliminary microscopic examination of prepared tissues, and follow-up examination of prepared tissues after immunohistochemical staining or genetic analysis.

Pathology
Tumors have characteristics that allow the determination of malignancy and how they will evolve, and determining these characteristics will allow the medical team to determine the management plan.

Anaplasia or dedifferentiation: loss of differentiation of cells and of their orientation to one another and blood vessels, a characteristic of anaplastic tumor tissue. Anaplastic cells have lost total control of their normal functions and many have deteriorated cell structures. Anaplastic cells often have abnormally high nuclear-to-cytoplasmic ratios, and many are multinucleated. Additionally, the nucleus of anaplastic cells is usually unnaturally shaped or oversized. Cells can become anaplastic in two ways: neoplastic tumor cells can dedifferentiate to become anaplasias (the dedifferentiation causes the cells to lose all of their normal structure/function), or cancer stem cells can increase their capacity to multiply (i.e., uncontrollable growth due to failure of differentiation).

Atypia: an indication of abnormality of a cell (which may be indicative of malignancy). Significance of the abnormality is highly dependent on context.

Neoplasia: the (uncontrolled) division of cells. As such, neoplasia is not problematic but its consequences are: the uncontrolled division of cells means that the mass of a neoplasm increases in size, and in a confined space such as the intracranial cavity this quickly becomes problematic because the mass invades the space of the brain pushing it aside, leading to compression of the brain tissue and increased intracranial pressure and destruction of brain parenchyma. Increased intracranial pressure (ICP) may be attributable to the direct mass effect of the tumor, increased blood volume, or increased cerebrospinal fluid (CSF) volume, which may, in turn, have secondary symptoms.

Necrosis: the (premature) death of cells, caused by external factors such as infection, toxin or trauma. Necrotic cells send the wrong chemical signals which prevent phagocytes from disposing of the dead cells, leading to a buildup of dead tissue, cell debris and toxins at or near the site of the necrotic cells

Arterial and venous hypoxia, or the deprivation of adequate oxygen supply to certain areas of the brain, occurs when a tumor makes use of nearby blood vessels for its supply of blood and the neoplasm enters into competition for nutrients with the surrounding brain tissue. More generally a neoplasm may cause release of metabolic end products (e.g., free radicals, altered electrolytes, neurotransmitters), and release and recruitment of cellular mediators (e.g., cytokines) that disrupt normal parenchymal function.

Classification
Tumors can be benign or malignant, can occur in different parts of the brain, and may be classified as primary or secondary. A primary tumor is one that has started in the brain, as opposed to a metastatic tumor, which is one that has spread to the brain from another area of the body. The incidence of metastatic tumors is approximately four times greater than primary tumors. Tumors may or may not be symptomatic: some tumors are discovered because the patient has symptoms, others show up incidentally on an imaging scan, or at an autopsy.

Grading of the tumors of the central nervous system commonly occurs on a 4-point scale (I-IV) created by the World Health Organization in 1993. Grade I tumors are the least severe and commonly associated with long-term survival, with severity and prognosis worsening as the grade increases. Low-grade tumors are often benign, while higher grades are aggressively malignant and/or metastatic. Other grading scales do exist, many based upon the same criteria as the WHO scale and graded from I-IV.

Primary
The most common primary brain tumors are:
 * Gliomas (50.4%)
 * Meningiomas (20.8%)
 * Pituitary adenomas (15%)
 * Nerve sheath tumors (10%)

These common tumors can also be organized according to tissue of origin as shown below:

Secondary
Secondary tumors of the brain are metastatic and have invaded the brain from cancers originating in other organs. This means that a cancerous neoplasm has developed in another organ elsewhere in the body and that cancer cells have leaked from that primary tumor and then entered the lymphatic system and blood vessels. They then circulate through the bloodstream, and are deposited in the brain. There, these cells continue growing and dividing, becoming another invasive neoplasm of primary cancer's tissue. Secondary tumors of the brain are very common in the terminal phases of patients with an incurable metastasized cancer; the most common types of cancers that bring about secondary tumors of the brain are lung cancer, breast cancer, malignant melanoma, kidney cancer, and colon cancer (in decreasing order of frequency).

Secondary brain tumors are more common than primary ones; in the United States, there are about 170,000 new cases every year. Secondary brain tumors are the most common cause of tumors in the intracranial cavity. The skull bone structure can also be subject to a neoplasm that by its very nature reduces the volume of the intracranial cavity, and can damage the brain.

By behavior
Brain tumors or intracranial neoplasms can be cancerous (malignant) or non-cancerous (benign). However, the definitions of malignant or benign neoplasms differ from those commonly used in other types of cancerous or non-cancerous neoplasms in the body. In cancers elsewhere in the body, three malignant properties differentiate benign tumors from malignant forms of cancer: benign tumors are self-limited and do not invade or metastasize. Characteristics of malignant tumors include:
 * uncontrolled mitosis (growth by division beyond the normal limits)
 * anaplasia: the cells in the neoplasm have an obviously different form (in size and shape). Anaplastic cells display marked pleomorphism. The cell nuclei are characteristically extremely hyperchromatic (darkly stained) and enlarged; the nucleus might have the same size as the cytoplasm of the cell (nuclear-cytoplasmic ratio may approach 1:1, instead of the normal 1:4 or 1:6 ratio). Giant cells – considerably larger than their neighbors – may form and possess either one enormous nucleus or several nuclei (syncytia). Anaplastic nuclei are variable and bizarre in size and shape.
 * invasion or infiltration (medical literature uses these terms as synonymous equivalents. However, for clarity, the articles that follow adhere to a convention that they mean slightly different things; this convention is not followed outside these articles):
 * Invasion or invasiveness is the spatial expansion of the tumor through uncontrolled mitosis, in the sense that the neoplasm invades the space occupied by adjacent tissue, thereby pushing the other tissue aside and eventually compressing the tissue. Often these tumors are associated with clearly outlined tumors in imaging.
 * Infiltration is the behavior of the tumor either to grow (microscopic) tentacles that push into the surrounding tissue (often making the outline of the tumor undefined or diffuse) or to have tumor cells "seeded" into the tissue beyond the circumference of the tumorous mass; this does not mean that an infiltrative tumor does not take up space or does not compress the surrounding tissue as it grows, but an infiltrating neoplasm makes it difficult to say where the tumor ends and the healthy tissue starts.
 * metastasis (spread to other locations in the body via lymph or blood).

Of the above malignant characteristics, some elements do not apply to primary neoplasms of the brain:
 * Primary brain tumors rarely metastasize to other organs; some forms of primary brain tumors can metastasize but will not spread outside the intracranial cavity or the central spinal canal. Due to the BBB, cancerous cells of a primary neoplasm cannot enter the bloodstream and get carried to another location in the body. (Occasional isolated case reports suggest spread of certain brain tumors outside the central nervous system, e.g. bone metastasis of glioblastoma. )
 * Primary brain tumors generally are invasive (i.e. they will expand spatially and intrude into the space occupied by other brain tissue and compress those brain tissues); however, some of the more malignant primary brain tumors will infiltrate the surrounding tissue.

By genetics
In 2016, the WHO restructured their classifications of some categories of gliomas to include distinct genetic mutations that have been useful in differentiating tumor types, prognoses, and treatment responses. Genetic mutations are typically detected via immunohistochemistry, a technique that visualizes the presence or absence of a targeted protein via staining.
 * Mutations in IDH1 and IDH2 genes are commonly found in low-grade gliomas
 * Loss of both IDH genes combined with loss of chromosome arms 1p and 19q indicates the tumor is an oligodendroglioma
 * Loss of TP53 and ATRX characterizes astrocytomas
 * Genes EGFR, TERT, and PTEN, are commonly altered in gliomas and are useful in differentiating tumor grade and biology

Specific types
Anaplastic astrocytoma, Anaplastic oligodendroglioma, Astrocytoma, Central neurocytoma, Choroid plexus carcinoma, Choroid plexus papilloma, Choroid plexus tumor, Colloid cyst, Dysembryoplastic neuroepithelial tumour, Ependymal tumor, Fibrillary astrocytoma, Giant-cell glioblastoma, Glioblastoma, Gliomatosis cerebri, Gliosarcoma, Hemangiopericytoma, Medulloblastoma, Medulloepithelioma, Meningeal carcinomatosis, Neuroblastoma, Neurocytoma, Oligoastrocytoma, Oligodendroglioma, Optic nerve sheath meningioma, Pediatric ependymoma, Pilocytic astrocytoma, Pinealoblastoma, Pineocytoma, Pleomorphic anaplastic neuroblastoma, Pleomorphic xanthoastrocytoma, Primary central nervous system lymphoma, Sphenoid wing meningioma, Subependymal giant cell astrocytoma, Subependymoma, Trilateral retinoblastoma.

Treatment
A medical team generally assesses the treatment options and presents them to the person affected and their family. Various types of treatment are available depending on tumor type and location, and may be combined to produce the best chances of survival:
 * Surgery: complete or partial resection of the tumor with the objective of removing as many tumor cells as possible.
 * Radiotherapy: the most commonly used treatment for brain tumors; the tumor is irradiated with beta, x rays or gamma rays.
 * Chemotherapy: a treatment option for cancer, however, it is not always used to treat brain tumors as the blood–brain barrier can prevent some drugs from reaching the cancerous cells.
 * A variety of experimental therapies are available through clinical trials.

Survival rates in primary brain tumors depend on the type of tumor, age, functional status of the patient, the extent of surgical removal and other factors specific to each case.

Standard care for anaplastic oligodendrogliomas and anaplastic oligoastrocytomas is surgery followed by radiotherapy. One study found a survival benefit for the addition of chemotherapy to radiotherapy after surgery, compared with radiotherapy alone.

Surgery
The primary and most desired course of action described in medical literature is surgical removal (resection) via craniotomy. Minimally invasive techniques are becoming the dominant trend in neurosurgical oncology. The main objective of surgery is to remove as many tumor cells as possible, with complete removal being the best outcome and cytoreduction ("debulking") of the tumor otherwise. A Gross Total Resection (GTR) occurs when all visible signs of the tumor are removed, and subsequent scans show no apparent tumor. In some cases access to the tumor is impossible and impedes or prohibits surgery.

Many meningiomas, with the exception of some tumors located at the skull base, can be successfully removed surgically. Most pituitary adenomas can be removed surgically, often using a minimally invasive approach through the nasal cavity and skull base (trans-nasal, trans-sphenoidal approach). Large pituitary adenomas require a craniotomy (opening of the skull) for their removal. Radiotherapy, including stereotactic approaches, is reserved for inoperable cases.

Several current research studies aim to improve the surgical removal of brain tumors by labeling tumor cells with 5-aminolevulinic acid that causes them to fluoresce. Postoperative radiotherapy and chemotherapy are integral parts of the therapeutic standard for malignant tumors.

Multiple metastatic tumors are generally treated with radiotherapy and chemotherapy rather than surgery and the prognosis in such cases is determined by the primary tumor, and is generally poor.

Radiation therapy
The goal of radiation therapy is to kill tumor cells while leaving normal brain tissue unharmed. In standard external beam radiation therapy, multiple treatments of standard-dose "fractions" of radiation are applied to the brain. This process is repeated for a total of 10 to 30 treatments, depending on the type of tumor. This additional treatment provides some patients with improved outcomes and longer survival rates.

Radiosurgery is a treatment method that uses computerized calculations to focus radiation at the site of the tumor while minimizing the radiation dose to the surrounding brain. Radiosurgery may be an adjunct to other treatments, or it may represent the primary treatment technique for some tumors. Forms used include stereotactic radiosurgery, such as Gamma knife, Cyberknife or Novalis Tx radiosurgery.

Radiotherapy is the most common treatment for secondary brain tumors. The amount of radiotherapy depends on the size of the area of the brain affected by cancer. Conventional external beam "whole-brain radiotherapy treatment" (WBRT) or "whole-brain irradiation" may be suggested if there is a risk that other secondary tumors will develop in the future. Stereotactic radiotherapy is usually recommended in cases involving fewer than three small secondary brain tumors. Radiotherapy may be used following, or in some cases in place of, resection of the tumor. Forms of radiotherapy used for brain cancer include external beam radiation therapy, the most common, and brachytherapy and proton therapy, the last especially used for children.

People who receive stereotactic radiosurgery (SRS) and whole-brain radiation therapy (WBRT) for the treatment of metastatic brain tumors have more than twice the risk of developing learning and memory problems than those treated with SRS alone. Results of a 2021 systematic review found that when using SRS as the initial treatment, survival or death related to brain metastasis was not greater than alone versus SRS with WBRT.

Postoperative conventional daily radiotherapy improves survival for adults with good functional well-being and high grade glioma compared to no postoperative radiotherapy. Hypofractionated radiation therapy has similar efficacy for survival as compared to conventional radiotherapy, particularly for individuals aged 60 and older with glioblastoma.

Chemotherapy
Patients undergoing chemotherapy are administered drugs designed to kill tumor cells. Although chemotherapy may improve overall survival in patients with the most malignant primary brain tumors, it does so in only about 20 percent of patients. Chemotherapy is often used in young children instead of radiation, as radiation may have negative effects on the developing brain. The decision to prescribe this treatment is based on a patient's overall health, type of tumor, and extent of cancer. The toxicity and many side effects of the drugs, and the uncertain outcome of chemotherapy in brain tumors puts this treatment further down the line of treatment options with surgery and radiation therapy preferred.

UCLA Neuro-Oncology publishes real-time survival data for patients with a diagnosis of glioblastoma. They are the only institution in the United States that displays how brain tumor patients are performing on current therapies. They also show a listing of chemotherapy agents used to treat high-grade glioma tumors.

Genetic mutations have significant effects on the effectiveness of chemotherapy. Gliomas with IDH1 or IDH2 mutations respond better to chemotherapy than those without the mutation. Loss of chromosome arms 1p and 19q also indicate better response to chemoradiation.

Other
A shunt may be used to relieve symptoms caused by intracranial pressure, by reducing the build-up of fluid (hydrocephalus) caused by the blockage of the free flow of cerebrospinal fluid.

Prognosis
The prognosis of brain cancer depends on the type of cancer diagnosed. Medulloblastoma has a good prognosis with chemotherapy, radiotherapy, and surgical resection while glioblastoma has a median survival of only 15 months even with aggressive chemoradiotherapy and surgery. Brainstem gliomas have the poorest prognosis of any form of brain cancer, with most patients dying within one year, even with therapy that typically consists of radiation to the tumor along with corticosteroids. However, one type, focal brainstem gliomas in children, seems open to exceptional prognosis and long-term survival has frequently been reported.

Prognosis is also affected by presentation of genetic mutations. Certain mutations provide better prognosis than others. IDH1 and IDH2 mutations in gliomas, as well as deletion of chromosome arms 1p and 19q, generally indicate better prognosis. TP53, ATRX, EGFR, PTEN, and TERT mutations are also useful in determining prognosis.

Glioblastoma
Glioblastoma is the most aggressive (grade 4) and most common form of a malignant primary brain tumor. Even when aggressive multimodality therapy consisting of radiotherapy, chemotherapy, and surgical excision is used, median survival is only 15–18 months. Standard therapy for glioblastoma consists of maximal surgical resection of the tumor, followed by radiotherapy between two and four weeks after the surgical procedure to remove the cancer, then by chemotherapy, such as temozolomide. Most patients with glioblastoma take a corticosteroid, typically dexamethasone, during their illness to relieve symptoms. Experimental treatments include targeted therapy, gamma knife radiosurgery, boron neutron capture therapy, gene therapy, and chemowafer implants.

Oligodendrogliomas
Oligodendrogliomas are incurable but slowly progressive malignant brain tumors. They can be treated with surgical resection, chemotherapy, radiotherapy or a combination. For some suspected low-grade (grade II) tumors, only a course of watchful waiting and symptomatic therapy is opted for. These tumors show co-deletions of the p and q arms of chromosome 1 and chromosome 19 respectively (1p19q co-deletion) and have been found to be especially chemosensitive with one report claiming them to be one of the most chemosensitive tumors. A median survival of up to 16.7 years has been reported for grade II oligodendrogliomas.

Acoustic neuroma
Acoustic neuromas are non-cancerous tumors. They can be treated with surgery, radiation therapy, or observation. Early intervention with surgery or radiation is recommended to prevent progressive hearing loss.

Epidemiology
Figures for incidences of cancers of the brain show a significant difference between more- and less-developed countries (the less-developed countries have lower incidences of tumors of the brain). This could be explained by undiagnosed tumor-related deaths (patients in extremely poor situations do not get diagnosed, simply because they do not have access to the modern diagnostic facilities required to diagnose a brain tumor) and by deaths caused by other poverty-related causes that preempt a patient's life before tumors develop or tumors become life-threatening. Nevertheless, statistics suggest that certain forms of primary brain tumors are more common among certain populations.

The incidence of low-grade astrocytoma has not been shown to vary significantly with nationality. However, studies examining the incidence of malignant central nervous system (CNS) tumors have shown some variation with national origin. Since some high-grade lesions arise from low-grade tumors, these trends are worth mentioning. Specifically, the incidence of CNS tumors in the United States, Israel, and the Nordic countries is relatively high, while Japan and Asian countries have a lower incidence. These differences probably reflect some biological differences as well as differences in pathologic diagnosis and reporting.

Worldwide data on incidence of cancer can be found at the WHO (World Health Organization) and is handled by the IARC (International Agency for Research on Cancer) located in France.

United States
In the United States in 2015, approximately 166,039 people were living with brain or other central nervous system tumors. Over 2018, it was projected that there would be 23,880 new cases of brain tumors and 16,830 deaths in 2018 as a result, accounting for 1.4 percent of all cancers and 2.8 percent of all cancer deaths. Median age of diagnosis was 58 years old, while median age of death was 65. Diagnosis was slightly more common in males, at approximately 7.5 cases per 100 000 people, while females saw 2 fewer at 5.4. Deaths as a result of brain cancer were 5.3 per 100 000 for males, and 3.6 per 100 000 for females, making brain cancer the 10th leading cause of cancer death in the United States. Overall lifetime risk of developing brain cancer is approximated at 0.6 percent for men and women.

UK
Brain, other CNS or intracranial tumors are the ninth most common cancer in the UK (around 10,600 people were diagnosed in 2013), and it is the eighth most common cause of cancer death (around 5,200 people died in 2012). White British patients with brain tumour are 30% more likely to die within a year of diagnosis than patients from other ethnicities. The reason for this is unknown.

Children
In the United States more than 28,000 people under 20 are estimated to have a brain tumor. About 3,720 new cases of brain tumors are expected to be diagnosed in those under 15 in 2019. Higher rates were reported in 1985–1994 than in 1975–1983. There is some debate as to the reasons; one theory is that the trend is the result of improved diagnosis and reporting, since the jump occurred at the same time that MRIs became available widely, and there was no coincident jump in mortality. Central nervous system tumors make up 20–25 percent of cancers in children.

The average survival rate for all primary brain cancers in children is 74%. Brain cancers are the most common cancer in children under 19, are result in more death in this group than leukemia. Younger people do less well.

The most common brain tumor types in children (0–14) are: pilocytic astrocytoma, malignant glioma, medulloblastoma, neuronal and mixed neuronal-glial tumors, and ependymoma.

In children under 2, about 70% of brain tumors are medulloblastomas, ependymomas, and low-grade gliomas. Less commonly, and seen usually in infants, are teratomas and atypical teratoid rhabdoid tumors. Germ cell tumors, including teratomas, make up just 3% of pediatric primary brain tumors, but the worldwide incidence varies significantly.

In the UK, 429 children aged 14 and under are diagnosed with a brain tumour on average each year, and 563 children and young people under the age of 19 are diagnosed.

Immunotherapy
Cancer immunotherapy is being actively studied. For malignant gliomas no therapy has been shown to improve life expectancy as of 2015.

Vesicular stomatitis virus
In 2000, researchers used the vesicular stomatitis virus (VSV) to infect and kill cancer cells without affecting healthy cells.

Retroviral replicating vectors
Led by Prof. Nori Kasahara, researchers from USC, who are now at UCLA, reported in 2001 the first successful example of applying the use of retroviral replicating vectors towards transducing cell lines derived from solid tumors. Building on this initial work, the researchers applied the technology to in vivo models of cancer and in 2005 reported a long-term survival benefit in an experimental brain tumor animal model. Subsequently, in preparation for human clinical trials, this technology was further developed by Tocagen (a pharmaceutical company primarily focused on brain cancer treatments) as a combination treatment (Toca 511 & Toca FC). This has been under investigation since 2010 in a Phase I/II clinical trial for the potential treatment of recurrent high-grade glioma including glioblastoma and anaplastic astrocytoma. No results have yet been published.

Non-invasive detection
Efforts to detect and monitor development and treatment response of brain tumors by liquid biopsy from blood, cerebrospinal fluid or urine, are in the early stages of development.

title: Brain tumor


text:
Batch processing

Computerized batch processing is a method of running software programs called jobs in batches automatically. While users are required to submit the jobs, no other interaction by the user is required to process the batch. Batches may automatically be run at scheduled times as well as being run contingent on the availability of computer resources.

History
The term "batch processing" originates in the traditional classification of methods of production as job production (one-off production), batch production (production of a "batch" of multiple items at once, one stage at a time), and flow production (mass production, all stages in process at once).

Early history
Early computers were capable of running only one program at a time. Each user had sole control of the machine for a scheduled period of time. They would arrive at the computer with program and data, often on punched paper cards and magnetic or paper tape, and would load their program, run and debug it, and carry off their output when done.

As computers became faster the setup and takedown time became a larger percentage of available computer time. Programs called monitors, the forerunners of operating systems, were developed which could process a series, or "batch", of programs, often from magnetic tape prepared offline. The monitor would be loaded into the computer and run the first job of the batch. At the end of the job it would regain control and load and run the next until the batch was complete. Often the output of the batch would be written to magnetic tape and printed or punched offline. Examples of monitors were IBM's Fortran Monitor System, SOS (Share Operating System), and finally IBSYS for IBM's 709x systems in 1960.

Third-generation systems
capable of multiprogramming began to appear in the 1960s. Instead of running one batch job at a time, these systems can have multiple batch programs running at the same time in order to keep the system as busy as possible. One or more programs might be awaiting input, one actively running on the CPU, and others generating output. Instead of offline input and output, programs called spoolers read jobs from cards, disk, or remote terminals and place them in a job queue to be run. In order to prevent deadlocks the job scheduler needs to know each job's resource requirements—memory, magnetic tapes, mountable disks, etc., so various scripting languages were developed to supply this information in a structured way. Probably the most well-known is IBM's Job Control Language (JCL). Job schedulers select jobs to run according to a variety of criteria, including priority, memory size, etc. Remote batch is a procedure for submitting batch jobs from remote terminals, often equipped with a punch card reader and a line printer. Sometimes asymmetric multiprocessing is used to spool batch input and output for one or more large computers using an attached smaller and less-expensive system, as in the IBM System/360 Attached Support Processor.

Later history
The first general purpose time sharing system, Compatible Time-Sharing System (CTSS), was compatible with batch processing. This facilitated transitioning from batch processing to interactive computing.

From the late 1960s onwards, interactive computing such as via text-based computer terminal interfaces (as in Unix shells or read-eval-print loops), and later graphical user interfaces became common. Non-interactive computation, both one-off jobs such as compilation, and processing of multiple items in batches, became retrospectively referred to as batch processing, and the term batch job (in early use often "batch of jobs") became common. Early use is particularly found at the University of Michigan, around the Michigan Terminal System (MTS).

Although timesharing did exist, its use was not robust enough for corporate data processing; none of this was related to the earlier unit record equipment, which was human-operated.

Ongoing
Non-interactive computation remains pervasive in computing, both for general data processing and for system "housekeeping" tasks (using system software). A high-level program (executing multiple programs, with some additional "glue" logic) is today most often called a script, and written in scripting languages, particularly shell scripts for system tasks; in IBM PC DOS and MS-DOS this is instead known as a batch file. That includes UNIX-based computers, Microsoft Windows, macOS (whose foundation is the BSD Unix kernel), and even smartphones. A running script, particularly one executed from an interactive login session, is often known as a job, but that term is used very ambiguously.

"There is no direct counterpart to z/OS batch processing in PC or UNIX systems. Batch jobs are typically executed at a scheduled time or on an as-needed basis. Perhaps the closest comparison is with processes run by an at or cron command in UNIX, although the differences are significant."

Modern systems
Batch applications are still critical in most organizations in large part because many common business processes are amenable to batch processing. While online systems can also function when manual intervention is not desired, they are not typically optimized to perform high-volume, repetitive tasks. Therefore, even new systems usually contain one or more batch applications for updating information at the end of the day, generating reports, printing documents, and other non-interactive tasks that must complete reliably within certain business deadlines.

Some applications are amenable to flow processing, namely those that only need data from a single input at once (not totals, for instance): start the next step for each input as it completes the previous step. In this case flow processing lowers latency for individual inputs, allowing them to be completed without waiting for the entire batch to finish. However, many applications require data from all records, notably computations such as totals. In this case the entire batch must be completed before one has a usable result: partial results are not usable.

Modern batch applications make use of modern batch frameworks such as Jem The Bee, Spring Batch or implementations of JSR 352 written for Java, and other frameworks for other programming languages, to provide the fault tolerance and scalability required for high-volume processing. In order to ensure high-speed processing, batch applications are often integrated with grid computing solutions to partition a batch job over a large number of processors, although there are significant programming challenges in doing so. High volume batch processing places particularly heavy demands on system and application architectures as well. Architectures that feature strong input/output performance and vertical scalability, including modern mainframe computers, tend to provide better batch performance than alternatives.

Scripting languages became popular as they evolved along with batch processing.

Batch window
A batch window is "a period of less-intensive online activity", when the computer system is able to run batch jobs without interference from, or with, interactive online systems.

A bank's end-of-day (EOD) jobs require the concept of cutover, where transaction and data are cut off for a particular day's batch activity ("deposits after 3 PM will be processed the next day").

As requirements for online systems uptime expanded to support globalization, the Internet, and other business needs, the batch window shrank and increasing emphasis was placed on techniques that would require online data to be available for a maximum amount of time.

Batch size
The batch size refers to the number of work units to be processed within one batch operation. Some examples are:
 * The number of lines from a file to load into a database before committing the transaction.
 * The number of messages to dequeue from a queue.
 * The number of requests to send within one payload.

Common batch processing usage

 * Efficient bulk database updates and automated transaction processing, as contrasted to interactive online transaction processing (OLTP) applications. The extract, transform, load (ETL) step in populating data warehouses is inherently a batch process in most implementations.
 * Performing bulk operations on digital images such as resizing, conversion, watermarking, or otherwise editing a group of image files.
 * Converting computer files from one format to another. For example, a batch job may convert proprietary and legacy files to common standard formats for end-user queries and display.
 * Training Machine Learning models. For example, an e-commerce website might want to process customer transactions in a hourly batch to update the model that produces related product recommendations, in order to save computational resources.

Notable batch scheduling and execution environments
The IBM mainframe z/OS operating system or platform has arguably the most highly refined and evolved set of batch processing facilities owing to its origins, long history, and continuing evolution. Today such systems commonly support hundreds or even thousands of concurrent online and batch tasks within a single operating system image. Technologies that aid concurrent batch and online processing include Job Control Language (JCL), scripting languages such as REXX, Job Entry Subsystem (JES2 and JES3), Workload Manager (WLM), Automatic Restart Manager (ARM), Resource Recovery Services (RRS), IBM Db2 data sharing, Parallel Sysplex, unique performance optimizations such as HiperDispatch, I/O channel architecture, and several others.

The Unix programs,  , and   (today   is a variant of  ) allow for complex scheduling of jobs. Windows has a job scheduler. Most high-performance computing clusters use batch processing to maximize cluster usage.

title: Batch processing