In announcing his indefinite medical leave from Apple, Jobs offered no details about his condition. But his gaunt appearance and cryptic message, which offered no return date, has triggered worried speculation.
Doctors reiterated that Jobs' rare type of disease, called neuroendocrine cancer, is known to be slow-growing and even treatable. And complications related to liver transplants, such as infection and duct blockage, can often be fixed. But both pose substantial lifelong risk.
"The worst thing, in our mind, would be recurrence of the tumor," said Dr. Simon Lo, director of the pancreatic disease program at Cedars-Sinai Medical Center in Los Angeles, who has not treated Jobs and has no direct information about his diagnosis.
"But even if it recurs, it could be slow in progressing," he added.
There is relatively little data on long-term survival of patients such as Jobs, but statistics suggest that about half of patients with pancreatic neuroendocrine cancers who receive liver transplants live for five years. Individual outcomes may vary, based on the subtype of tumor.
"Those are pretty good odds," said Lo.
In 2004, Jobs disclosed that he had been diagnosed with this rare form of pancreatic cancer and
had been treated with surgery -- and told he was cured.Five years later, he had his liver removed and received a transplant, indicating that the cancer had metastasized. The liver is the most common place for pancreatic cancers to spread, because blood flows from one organ to the other.
According to a report by University of North Carolina at Chapel Hill abdominal transplant surgeon David Gerber, liver metastases are the main cause of death for patients with this type of cancer -- so a transplant can significantly prolong survival.
But transplants pose their own risks, particularly with cancer patients.
That's because the immunosuppressant drugs needed to prevent rejection make the body less able to fend off infections or new malignancies.
Moreover, if any tiny pockets of cancer cells remain, hidden, the introduction of these immunosuppressant drugs can cause them to flare up, Dr. Anthony Heaney, an endocrinologist at UCLA's Ronald Reagan Medical Center, told The Los Angeles Times. So transplants are performed only if doctors believe the cancer is completely gone.
Fortunately, drug treatment is generally not as rigorous for liver patients as it is for patients receiving other organs. Some liver transplant patients can even be safely weaned off medicines, according to longtime transplant surgeon Oscar Salvatierra of Stanford University's School of Medicine.
Yet other postsurgical transplant problems may be encountered, said Lo, such as blockage of a duct. That happens when the liver is removed; scar tissue may form and prevent bile from flowing properly. Surgery can also cause adhesions, or "kinks," in the digestive system.
And there is always the risk that the organ will be rejected, although that recedes with time. There are few reported cases of cancer patients who receive second livers after the first one is rejected.
Finally, patients who have lost their pancreas may have hormonal problems, altering how the body secretes substances like insulin.
If a tumor has reappeared in a different part of the body -- typically, the abdomen -- it can be treated with surgery, particularly if it is localized and large, according to Lo and Dr. Waldo Concepcion, a Stanford University transplant expert. In this circumstance, levels of immunosuppressant drugs would be adjusted. And a new medicine would be introduced, to attack the malignant cells.
"The whole idea is to control the spread," said Lo.
Contact Lisa M. Krieger at 408-920-5565.
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