LOS ANGELES AND SAN FRANCISCO — Apple Inc. Chief Executive Steve Jobs broke with his usual code of secrecy Monday to explain his health problems, but the disclosure that a hormone imbalance was causing his noticeable weight loss will probably do little to tamp down concerns.
Medical experts said a hormone imbalance in a pancreatic cancer survivor raises red flags about a possible recurrence. Jobs said in 2004 that he had undergone surgery to treat a rare form of the deadly disease.
Although Jobs is known as one of the nation's most intensely private corporate leaders, he issued an open letter Monday in which he tried to assure Apple investors and customers that he was healthy enough to lead the pioneering technology company he co-founded.
The 53-year-old CEO said his doctors discovered his condition had been "robbing" his body of proteins needed for good nutrition. He is undergoing treatment, which he described as simple and straightforward.
For The Record
Los Angeles Times Thursday, January 08, 2009 Home Edition Main News Part A Page 2 National Desk 1 inches; 36 words Type of Material: Correction
Steve Jobs: An article in Section A on Tuesday about the health of Apple Chief Executive Steve Jobs said Times staff writer Dawn C. Chmielewski was reporting from Los Angeles. She was reporting from San Francisco.
He did not mention cancer in his letter.
"I've said more than I wanted to say, and all that I am going to say, about this," Jobs wrote.
Several medical experts, who had no access to Jobs' health records, said problems other than cancer could have caused a hormone imbalance. For example, the surgery to remove his tumor could have left Jobs with a pancreas too small to produce the necessary enzymes.
Yet hormone imbalances are common in people who have an active neuroendocrine tumor, not in people who have been cured of the cancer, said Dr. Selwyn M. Vickers, chairman of the surgery department at the University of Minnesota.
An Apple spokesman declined to comment. The board said it would give Jobs its "complete and unwavering support" while he recovered.
Jobs noted that he spent this holiday season in an atypical way: with his family, rather than preparing for today's keynote address at the annual Macworld Conference & Expo in San Francisco. He'll miss delivering the speech for the first time since 1997. In years past, he used it to announce such industry-changing products as the feature-rich iPhone and iTunes music software.
The CEO has been inextricably linked to his company's fortunes since he helped revive the Mac computer and spurred a digital renaissance with the iPod media player and the iPhone. Jobs didn't do it alone, but continued anxiety over his health suggests the company has yet to persuade investors or Macolytes that Apple could survive without him.
"Why is everybody obsessed with Steve? I think the answer is very simple," said Paul Saffo, a technology forecaster who teaches at Stanford University. "Apple has not yet convinced the world that Apple without Steve will continue with the same powerful vision."
Last month, the Cupertino, Calif., company announced that Jobs would not give the Macworld presentation, triggering speculation that he was gravely ill. At the time, Apple, which is pulling out of the trade show after this year, said his participation "doesn't make sense."
In his letter, Jobs made light of the "stories of me on my deathbed" and said he would remain CEO while he recuperated. He said he expected to regain his lost weight by late spring.
"I will be the first one to step up and tell our Board of Directors if I can no longer continue to fulfill my duties as Apple's CEO," Jobs wrote. "I hope the Apple community will support me in my recovery and know that I will always put what is best for Apple first."
Jobs began looking unusually thin and drawn in June, when he introduced the latest generation of iPhones. Investors called for him to come clean about his health.
In the absence of any reliable information from the company, the blogosphere filled in the blanks with wildly speculative reports that whipsawed the company's stock. Bloomberg, the financial news service, mistakenly published Jobs' obituary in August. And a false account on a CNN website claiming Jobs had suffered a heart attack caused Apple stock to plunge.
As recently as last week, the popular technology blog Gizmodo cited a single source who said Jobs' health was "rapidly declining." The account knocked Apple share prices down for part of a day.
Internet paparazzi have staked out Jobs' known Palo Alto haunts and broadcast information about his appearance. Self-described geek blogger Robert Scoble caused a stir last week, when he recounted his visit to a Palo Alto yogurt shop that Jobs patronizes. "They said he was in a couple of days ago and is in great health," Scoble wrote.
Patrick McGurn, special counsel at shareholder advisory firm RiskMetrics Group, faulted Apple for responding only when it was "clear there would be a feeding frenzy" at the trade show that would overshadow product news.