In mid-2004, Jobs announced to his employees that he had been diagnosed with a cancerous tumor in his pancreas. The prognosis for pancreatic cancer is usually very poor; Jobs, however, stated that he had a rare, far less aggressive type known as islet cell neuroendocrine tumor.

After initially resisting the idea of conventional medical intervention and embarking on a special diet to thwart the disease, Jobs underwent a pancreaticoduodenectomy (or “Whipple procedure”) in July 2004 that appeared to successfully remove the tumor. Apparently did not require nor receive chemotherapy or radiation therapy. During Jobs’ absence, Timothy D. Cook, head of worldwide sales and operations at Apple, ran the company.

Jobs at the 2008 Macworld Conference & ExpoIn early August 2006, Jobs delivered the keynote for Apple’s annual Worldwide Developers Conference. His “thin, almost gaunt” appearance and unusually “listless” delivery, together with his choice to delegate significant portions of his keynote to other presenters, inspired a flurry of media and Internet speculation about his health. In contrast, according to an Ars Technica journal report, WWDC attendees who saw Jobs in person said he “looked fine. Following the keynote, an Apple spokesperson said that “Steve’s health is robust.”

Two years later, similar concerns followed Jobs’ 2008 WWDC keynote address.[120] Apple officials stated Jobs was victim to a “common bug” and was taking antibiotics,[121] while others surmised his cachectic appearance was due to the Whipple procedure.[122] During a July conference call discussing Apple earnings, participants responded to repeated questions about Steve Jobs’ health by insisting that it was a “private matter.” Others, however, voiced the opinion that shareholders had a right to know more, given Jobs’ hands-on approach to running his company.[123] The New York Times published an article based on an off-the-record phone conversation with Jobs, noting that “while his health issues have amounted to a good deal more than ‘a common bug,’ they weren’t life-threatening and he doesn’t have a recurrence of cancer.”

On August 28, 2008, Bloomberg mistakenly published a 2500-word obituary of Jobs in its corporate news service, containing blank spaces for his age and cause of death. (News carriers customarily stockpile up-to-date obituaries to facilitate news delivery in the event of a well-known figure’s untimely death.) Although the error was promptly rectified, many news carriers and blogs reported on it, intensifying rumors concerning Jobs’ health. Jobs responded at Apple’s September 2008 Let’s Rock keynote by quoting Mark Twain: “Reports of my death are greatly exaggerated.”At a subsequent media event, Jobs concluded his presentation with a slide reading “110/70″, referring to his blood pressure, stating he would not address further questions about his health.

On December 16, 2008, Apple announced that marketing vice-president Phil Schiller would deliver the company’s final keynote address at the Macworld Conference and Expo 2009, again reviving questions about Jobs’ health. In a statement given on January 5, 2009 on Apple.com,Jobs said that he had been suffering from a “hormone imbalance” for several months. On January 14, 2009, in an internal Apple memo, Jobs wrote that in the previous week he had “learned that my health-related issues are more complex than I originally thought” and announced a six-month leave of absence until the end of June 2009 to allow him to better focus on his health. Tim Cook, who had previously acted as CEO in Jobs’ 2004 absence, became acting CEO of Apple, with Jobs still involved with “major strategic decisions.”

In April 2009, Jobs underwent a liver transplant at Methodist University Hospital Transplant Institute in Memphis, Tennessee. Jobs’ prognosis was “excellent.”

On January 17, 2011, one and a half years after Jobs returned from his liver transplant, Apple announced that he had been granted a medical leave of absence. Jobs announced his leave in a letter to employees, stating his decision was made “so he could focus on his health.” As during his 2009 medical leave, Apple announced that Tim Cook would run day-to-day operations and that Jobs would continue to be involved in major strategic decisions at the company.[138][139] Despite the leave, he made appearances at the iPad 2 launch event (March 2), the WWDC keynote introducing iCloud (June 6), and before the Cupertino city council (June 7).

Jobs announced his resignation from his role as Apple’s CEO on August 24, 2011. In the letter, Jobs wrote that he could “no longer meet [his] duties and expectations as Apple’s CEO.”[141] Seven weeks later, on October 5, 2011, Apple released a statement saying that Jobs had died of pancreatic cancer.

The statement read “We are deeply saddened to announce that Steve Jobs passed away today. Steve’s brilliance, passion and energy were the source of countless innovations that enrich and improve all of our lives. The world is immeasurably better because of Steve. His greatest love was for his wife, Laurene, and his family. Our hearts go out to them and to all who were touched by his extraordinary gifts.”

Jobs’s survivors included his wife, Laurene, to whom he was married for 20 years, their three children, and a fourth child from a previous relationship.