NEW YORK (Reuters Health) - For people at high genetic risk of pancreas cancer, screening for the disease might be worthwhile - particularly if they're senior citizens, a new study suggests.
On the other hand, the researchers say, it might not be worthwhile -- and it's too soon to make widespread recommendations on screening high-risk families.
Only about 3 of every 100 patients with pancreatic cancer have the "familial form."
But the findings in this group offer reason to be "cautiously hopeful" that there might be ways to detect the often-fatal cancer earlier, said lead researcher Dr. Emmy Ludwig, of Memorial Sloan-Kettering Cancer Center in New York.
The study, reported in the American Journal of Gastroenterology, focused on families affected by familial pancreatic cancer -- where the disease has affected two or more first-degree relatives. First-degree relatives are either parents and children, or siblings.
Pancreatic cancer, whether due to an inherited gene or not, has a dim prognosis. Only about five of every hundred patients are still alive 5 years after diagnosis. That's largely because it is rarely caught early. The symptoms include weight loss and liver problems that cause the skin to turn yellow, but those usually don't show up until the cancer has spread.
It would seem to make sense to screen people from families affected by familial pancreatic cancer, but there are still many questions. For example, researchers are not sure which tests can reliably detect pancreatic cancer in people without symptoms, which people from affected families should be screened, or at what age screening should start.
For the new study, Ludwig and her colleagues offered screening to 309 relatives of people with familial pancreatic cancer. Some had at least one first-degree relative who developed pancreatic cancer before age 50. Others had family members who developed pancreatic cancer at any age - not just a parent, child or sibling but also a grandparent, grandchild, aunt or uncle, or a sibling's child.
Some participants had gene mutations linked to hereditary pancreatic cancer, plus a family history of the disease.
Over 7 years, 109 people in the study underwent screening at least once with MRI scans of the pancreas. If the MRI showed something suspicious-looking, they could have further testing with endoscopic ultrasound, where an ultrasound probe is threaded down the throat and into the small intestine, where it is then aimed at the pancreas.
Overall, MRI scans caught potential problems in 18 study participants. Nine -- or 8 percent of the whole group - had abnormalities that could become cancer. Six later had surgery to remove these lesions, while the rest refused surgery and decided to keep up with screening.
Six of the nine patients with abnormal lesions were older than 65. Perhaps, the researchers say, this means screening after age 65 could prove most useful -- but that requires further study.
In fact, the usefulness of screening at all is still debatable. A number of groups worldwide are looking into this issue, and not all of the studies have had positive findings. In a study of 76 high-risk relatives, German researchers found that screening with endoscopic ultrasound detected a potentially pre-cancerous lesion in just one relative over 5 years.
"No single group has definitively proven that routine screening is of benefit," Ludwig told Reuters Health in an email. "Our findings, we feel, add to the growing literature that suggests screening may be worthwhile. None of us has proven it."
She said that larger, long-term studies at multiple centers are needed to figure out how, when and how often to screen relatives from affected families -- and to see whether screening actually saves lives.
"The real end point to screening is, 'Do we save lives?'" Ludwig said. And the only way to get that answer, she added, is with large multi-hospital studies that keep close track of participants for many years.
Screening apparently healthy people for a disease always has downsides. It often, for instance, leads to "false-positive" test results -- suspicious findings that later turn out to be nothing to worry about. In the meantime, however, false-positive results can lead to invasive procedures people don't really need, and unnecessary anxiety.
So studies are done to try to make sure that the benefits of screening outweigh the risks.
Right now, pancreatic cancer screening is not widely available. Furthermore, since its value isn't proven, insurance companies are unlikely to pay for it - and an average out-of-network MRI scan in the northeast U.S. costs nearly $3,000, according to information from an Aetna Inc. website.
Ludwig suggested that people from high-risk families who are interested in screening try to enroll in one of the studies being run out of several academic centers worldwide -- which, besides Sloan-Kettering, include centers in Baltimore and Seattle in the U.S., and Liverpool in the U.K.
SOURCE: http://bit.ly/gyZ8WQ American Journal of Gastroenterology, online April 5, 2011.
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