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.
Ultrasound Plus X-Rays Detect Cancer Earlier
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.
Blood Test Plus Ultrasound Detects Cancer
In a second study, researchers found that a combination of endoscopic ultrasound and a blood test for a tumor marker called CA19-9 helped to detect pancreatic cancer at an earlier stage in high-risk people.
So far, 272 people ages 50 to 80 with at least one first-degree relative who had the disease have been screened with the combination in the ongoing study.
In addition to family history, "age is another factor we can use to target people for screening," says researcher Richard Zubarik, MD, associate professor of medicine and chief of endoscopy at Fletcher Allen Health Care in Burlington, Vt. More than 90% of people who develop pancreatic cancer are over age 50, he tells WebMD.
CA 19-9 is often produced by pancreatic cancers, and its level is elevated in more than 90% of pancreatic cancer patients. It's typically used to gauge how well a treatment is working in those already diagnosed with pancreatic cancer.
The cost to detect one case of pancreatic cancer was just over $14,000, and the cost to detect precancerous abnormal cell growth was about $11,000.
"If we use this protocol, we can detect cancer at an early stage," Zubarik says.
Heavy Drinking, Smoking Raises Pancreatic Cancer Risk
Also at the meeting, researchers reported that heavy smokers and drinkers are at risk of developing the cancer much earlier than is typical.
The more tobacco and alcohol one consumes, the younger the age at which the disease tends to strike, and beer drinkers may be at particularly high risk, they say.
While previous studies have shown that smoking tobacco and drinking alcohol are risk factors for pancreatic cancer, "we didn't know if risk increased with dose," says Michelle A. Anderson, MD, assistant professor of medicine at the University of Michigan in Ann Arbor.
To find out, she and colleagues studied data on about 450 pancreatic cancer patients enrolled in an international patient registry.
The study showed that "the more a person smoked or drank, the younger the onset of the cancer, and that of the two, drinking has a worse effect," Anderson says.
Among the findings:
- People who drank more than three drinks a day were diagnosed with pancreatic cancer at an average age of 60 vs. 67.3 for teetotalers.
- Heavy smokers developed the cancer about two years earlier than people who didn't smoke or drink: 64.9 years old vs. 66.7 years old. Heavy smokers were defined as people who smoked 21 or more pack-years in a lifetime, or the equivalent of at least one pack a day for 21 years.
- Beer drinkers tended to develop pancreatic cancer at an earlier age than those who preferred wine or hard liquor. While the finding could have been due to chance, Anderson tells WebMD that she believes that the link will hold up when larger numbers of people are studied.
- The median age of onset for patients who drank only beer was 62.2 compared with 68.2 for those drinking other types of alcohol.
Anderson says that regardless of their choice of beverage, heavy drinkers and smokers may want to talk to their doctors about pancreatic cancer screening.
"Normally you wouldn't think about screening a 55-year-old with no family history. But if they're a heavy drinker or smoker, you may want to do it earlier," she says.