Apple co-founder Steve Jobs' death at the age of 56 followed a seven-year battle with a rare form of pancreatic cancer - the fourth leading cause of cancer-related deaths in the United States. The disease is hard to treat because it is difficult to diagnose. The pancreas is embedded deep in the abdomen, and often, symptoms of cancer become evident at a very late, advanced stage of the disease.
In 2004, Jobs announced he had undergone surgery for pancreatic cancer -- a mild and rare form of the disease called an islet-cell neuroendocrine tumor.
That form makes up about five percent of all of pancreatic cancers. It affects the cells that produce hormones that control blood sugar levels. The more deadly, and common, form appears in the exocrine cells of the pancreas that produce digestive enzymes.
The pancreas is a 15-centimeter-long gland tucked behind the stomach and below the liver. Pancreatic cancer can be hard to diagnose, since the early stages have no visible symptoms.
“Neuroendocrine tumor, when its detected early, it is curable with surgery alone," explained Dr. Khaled el-Shami, a cancer specialist at George Washington University Medical Center, in Washington. "And when it is advanced, meaning that it has spread from the pancreas to the liver, typically, or other organs - [then] this is [an] incurable disease.”
In 2009, five years after his cancer surgery, Jobs received a liver transplant.
"About five months ago I had a liver transplant. So I now have the liver of a mid-20's person,” Jobs said.
Dr. el-Shami says a liver transplant is an aggressive way of dealing with cancer, but it's no “magic bullet".
“It’s a balance between removing a big chunk of cancer in the liver and the risk of having a weakened immune system, which can encourage not only the original cancer to come back but also the emergence of other cancers,” the doctor explained.
While he never treated Steve Jobs and does not know the details of his case, Dr. Matthew Walsh, chairman of General Surgery at Cleveland Clinic says Jobs' cancer was never likely to be cured.
“Having gone through all the treatment, most patients might think that they are cured of the cancer. When it comes back, there is still a great uncertainty [about] what the length of your life will be. It tends to be a disease that does come back - does spread - does take your strength away sort of have all the cancer-associated symptoms and people still die from this type of cancer.”
Few details of Steve Jobs' health have ever been made public, but experts speculate that his cancer may have been a case of late diagnosis.