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May 20, 2008 -- For people at high risk of pancreatic cancer, innovative approaches to screening and surveillance are helping to catch tumors earlier, when they're more treatable.
The tests are already available at many major academic medical centers throughout the country. Researchers hope the new findings will help increase testing of high-risk patients who can gain the most benefit -- typically people whose relatives have had pancreatic cancer.
Currently, most people survive only months from diagnosis; only 4% survive five years. The reason: Pancreatic cancer symptoms typically don't develop until the cancer has spread beyond the pancreas and surgical removal of the cancer is no longer possible, says Mark P. Callery, MD, associate professor of surgery at Harvard Medical School and chief of the division of general surgery at Beth Israel Deaconess Medical Center.
Early detection can mean improved survival, and "now we're finding that with screening of people at high risk -- those with first- or second-degree relatives with the cancer -- we may have an impact on outcomes," Callery says.
If detected early, when still confined to the pancreas, the five-year survival rate can be as high as 33%.
Callery moderated a media briefing to discuss the findings at Digestive Disease Week 2008 in San Diego.
An estimated 37,680 people in the U.S. will be diagnosed with pancreatic cancer in 2008, according to the American Cancer Society. About 34,290 Americans will die of the disease, making it the fourth deadliest cancer.
In one new study, a combination of ultrasound and specialized X-rays helped to detect the cancer earlier in people with two or more family members with pancreatic cancer.
The findings are important because at least 10% of pancreatic cancer is inherited, says Teresa A. Brentnall, MD, associate professor of medicine at the division of gastroenterology at the University of Washington in Seattle.
First, the patients were given an endoscopic ultrasound, which involves passing a thin, flexible tube (endoscope) into a patient's gastrointestinal tract. A tiny ultrasound probe at its tip produces high-energy sound waves (ultrasound) that create images of surrounding tissue.
"It gives us a really nice view of the pancreas. We can find tiny lesions that are the earliest signs of pancreatic cancer," Brentnall says.
Patients with abnormal findings on the endoscopic ultrasound were then offered specialized X-rays of the ducts that carry bile from the liver or gallbladder to the small intestine. Sometimes pancreatic cancer causes these ducts to narrow and block or slow the flow of bile.
"The ducts should normally be nice and smooth. But in people with precancerous changes, they become bumpy and irregular," Brentnall tells WebMD.
If both tests were abnormal, patients were offered surgery to have their pancreas removed. None of 20 patients who had the operation developed pancreatic cancer during an average follow-up of seven years.
Without the surgery, these patients would have had a high risk of developing incurable cancer, she says.
However, the surgery is not without risks of its own. Without a pancreas, you don't produce insulin to regulate your blood sugar, causing you to develop insulin-dependent diabetes.