Fatal result of weight and smoke

Medical Matters: The renowned tenor, Luciano Pavarotti, who was treated for pancreatic cancer in New York last month, is now recuperating in his native Italy.

The 70-year-old opera singer was about to resume a farewell concert tour when he developed jaundice (a yellow tinge to the skin). Investigations showed he had pancreatic cancer and he was operated on to remove the tumour.

"Fortunately, the mass was able to be completely removed at surgery," his manager said in a statement. "Mr Pavarotti is recovering well and his physicians are encouraged by the physical and emotional resilience of their patient."

Pavarotti, who joined Placido Domingo and José Carreras to form the Three Tenors in 1990, has not enjoyed the best of health in recent years.

He was forced to postpone five concert dates earlier this year because of an infection in his spinal cord following back surgery. The overweight singer also had weight-reduction surgery following problems with his knees.

Cancer of the pancreas carries one of the worst prognoses of all types of malignancy. This is because it characteristically does not cause symptoms until it has reached an advanced stage.

Overall, fewer than 4 per cent of patients are still alive five years after diagnosis. Even for those patients such as Pavarotti, in whom the tumour is operable, only about 23 per cent remain free of the cancer.

The pancreas is a gland located behind the stomach at the back of the abdominal wall. Extending horizontally, it is shaped like a fish. Some six inches long, the gland has a wide head tapering to a narrow pointed tail.

The pancreas contains two separate glands: the exocrine and endocrine glands. The exocrine part produces a cocktail of enzymes that help us digest fat, proteins and carbohydrates in food. These enzymes are released into a tube called the pancreatic duct, which carries the pancreatic juices into the small intestine. Exocrine glands and ducts make up more than 95 per cent of the cells in the pancreas and are the source of the commonest type of pancreatic cancer.

A small percentage of pancreatic cells, arranged in clusters, are called endocrine cells and separately manufacture the hormones insulin and glucagon.

Almost 15 per cent of cancerous tumours of the pancreas are adenocarcinomas, meaning they originate in the glandular cells lining the pancreatic duct. Some two-thirds of these cancers are found in the head of the pancreas, with about a third developing in the tail of the gland.

According to the National Cancer Registry, in the region of 350 new cases of cancer of the pancreas occur in the Republic each year. The number of deaths from the condition represents 5 per cent of all cancer deaths annually.

What are the risk factors for developing cancer of the pancreas? By far the biggest is cigarette smoking. Almost 30 per cent of cases are thought to result directly from smoking; it is estimated that heavy smokers have a two-three times increased risk of getting the disease.

Age is another factor; pancreatic cancer is rare under the age of 50. Men are 20 per cent more likely than women to develop the cancer. Obesity is a definite risk factor, with overweight people such as Pavarotti 20 per cent more likely to develop pancreatic cancer. Chronic inflammation of the gland (chronic pancreatitis) and heavy occupational exposure to certain chemicals are other risks.

In terms of symptoms and signs, jaundice, weight loss and pain in the abdomen and back occur most frequently. Other symptoms include weakness, loss of appetite, nausea and vomiting.

Jaundice occurs in 82 per cent of patients with cancer in the head of the pancreas. It is the result of a blockage in the common bile duct that is pressed on by the cancer developing in the adjacent pancreatic duct at the head of the gland.

Bilirubin, a substance made in the liver, cannot then reach the small intestine. As a result, bilirubin accumulates in the tissues and the blood, leading to yellow eyes and skin.

If the person is lucky, jaundice occurs early in the growth of the cancer, leading to an early diagnosis. Potentially curative surgery - a Whipple procedure - can succeed in removing the entire cancer and reconnecting the bile duct to the small intestine.

However, less than 5 per cent of patients are suitable for this extensive operation.

More commonly, a small tube (stent) is placed in the bile duct via a flexible telescope to resist compression from the surrounding tumour and prevent unpleasant symptoms later in the illness.

Pancreatic cancer patients are also treated with chemotherapy and radiotherapy. A drug called 5-flurouracil was the chemotherapy drug of choice but recent studies have found gemcitabine and other agents to be more effective.

While it is good news that Pavarotti was suitable for surgery, whether we see him on stage again will depend on how he responds to six months of chemotherapy due to begin later this month.

Dr Muiris Houston is pleased to hear from readers but regrets he cannot answer individual medical queries.