In their declaration of originator Steve Jobs' death, at geezerhood 56, Apple officials did not name a limited drive of death. But the intellectual digital cheater had been battling pancreatic cancer since 2004.

Pancreatic cancer is digit of the faster broad cancers; exclusive most 4% of patients crapper wait to endure fivesome eld after their diagnosis. Each year, most 44,000 newborn cases are diagnosed in the U.S., and 37,000 grouping expire of the disease.

The pancreas contains digit types of glands: secreter glands that display enzymes that fortuity downbound fats and proteins, and secretor glands that attain hormones same insulin that set dulcify in the blood. Jobs died of tumors originating in the secretor glands, which are among the rarer forms of pancreatic cancer.

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In 2004, Jobs underwent surgery to vanish the cancer from his pancreas. In 2009, after attractive additional yield of epilepsy from Apple, Jobs had a liver infix in an essay to keep as much of his office duty as doable after his cancer had distribute beyond the pancreas. In January, he took a ordinal yield from the consort before resigning as CEO in August.

"I hit ever said if there ever came a period when I could no individual foregather my duties and expectations as Apple's CEO, I would be the prototypal to permit you know," Jobs wrote in a letter to the Apple commission of directors on August 24. "Unfortunately, that period has come."

According to experts, Jobs' was an hard scrutiny battle. "He not exclusive had cancer, he was battling the insusceptible quelling after the liver transplant," Dr. Timothy Donahue of the UCLA Center for Pancreatic Disease in Los Angeles, who had not aerated Jobs, told MSNBC.com. He noted that most patients who obtain liver transplants endure most digit eld after the surgery.

Standard treatments for pancreatic cancer allow the ordinary tumor-fighting strategies — surgery, chemotherapy, irradiation and, most recently, targeted antitumor drugs that haw slightly modify patients' lives. In 2005, the Food and Drug Administration authorised erlotinib, a verify that specifically targets ontogeny factors institute on cancer cells, for the communication of patients with modern pancreatic cancer who are receiving chemotherapy. The verify has been shown in trials to meliorate coverall activity by 23% after a assemblage when additional to turn chemotherapy. The tumors in patients existence aerated with erlotinib and chemo also amend more tardily than those in patients receiving chemotherapy alone.

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Because of the slummy forecasting of pancreatic cancer, however, some patients elite to essay deciding therapies, including a favourite therapy famous as the Gonzalez regimen, which involves conflict pancreatic tumors with pancreatic enzymes. Patients on the Gonzalez program also verify a super sort of nutritional supplements, including vitamins and minerals much as metal citrate, along with drink enemas performed twice a day.

The treatment's developer, Dr. saint Gonzalez of New York, has claimed that the ingest of pancreatic enzymes is a coercive artefact to bury the ontogeny of modern pancreatic cancer cells. But a think publicised in the Journal of Clinical Oncology in 2009, which compared groups of patients on the Gonzalez regiment to patients on accepted chemotherapy treatment, institute that those on chemo survived for a norm of 14 months patch those on the deciding therapy survived for a norm of exclusive 4.3 months.

Jobs is not reportable to hit proven the Gonzalez regimen, but he is famous to hit suscribed to deciding therapy. In a 2008 story, Fortune reportable that Jobs initially proven to impact his growth with fasting instead of surgery, presently after he was diagnosed in 2004. In January, Fortune reported that he had also prefabricated a hush-hush activate to Schweiz in 2009 for a radiation-based catecholamine treatment. The literal info aren't clear, but the University Hospital of Bale in Schweiz is famous for its primary modify of communication for neuroendocrine cancer, which is not acquirable in the U.S.

Whether these treatments helped to modify Jobs' chronicle or meliorate the calibre of his terminal life isn't clear. But cancer experts spoken assail that Jobs survived as daylong as he did, continuing to fisticuffs his disease. Other pancreatic cancer patients typically aren't as fortunate. Another high-profile patient, person Apostle Swayze, managed to springy for 20 months after his diagnosis, attractive plus of chemotherapy treatments. But, overall, patients' norm activity is mostly exclusive fivesome months.

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Jobs forfeited his effort with cancer at a instance when researchers are constantly actuation the boundaries of treatments, specially with antitumor agents that crapper bag in on abnormally ontogeny cells with crescendo precision. In the end, his cancer evidenced likewise modern to command in with modify the most original technologies.

"Apple has forfeited a intellectual and fictive genius, and the concern has forfeited an awful manlike being," Tim Cook, Jobs' progeny at Apple, wrote to employees on Wednesday. "Steve leaves behindhand a consort that exclusive he could hit built, and his fiber will forever be the groundwork of Apple."

Alice Park is a illustrator at TIME. Find her on Twitter at @aliceparkny. You crapper also move the communicating on TIME's Facebook page and on Twitter at @TIME.