Diabetes, pancreaticcancer link seen
By Larry Schuster,
UPI Science News
SAN FRANCISCO, (UPI) - Anew study strongly suggests that diabetes newly diagnosed in peopleat least 50 years old may be an indication of underlying early-stagepancreatic cancer, researchers reported Tuesday.
Older patients whose diabetesbegan late in life were 10 times more likely to be diagnosed withpancreatic cancer within three years following onset of diabetes.In the study, the link appeared especially pronounced for peoplein their 70s when diabetes first appeared.
Dr. Suresh T. Chari, ofthe Mayo Clinic in Rochester, Minn., said in theory, "ifyou can recognize this form of diabetes, then you could pick apatient you identify for pancreatic cancer early before they havesymptoms. It's like a flag."
Chari presented his report at the annual Digestive Disease Weekconference.
He told UPI that the studyrepresents "preliminary proof that that form of diabetescould be a marker for pancreatic cancer."
Chari and others were carefulto note that the research does not suggest diabetes causes thecancer, but instead said it presents further evidence that thepancreatic cancer is likely already established and the cancermay actually cause the diabetes. Chari said he has begun usingthe term "pancreatic cancer-induced diabetes" to emphasizethe point.
Not all late-onset casesof diabetes are associated with pancreatic cancer, however. Thegreat majority, perhaps 95 percent, is the relatively common type2 forms with no association to cancer. The diabetes that is linkedto cancer occurs in about one out of a hundred cases of late-onsetdiabetes, Chari said.
The cases used for the studycame from the Rochester Epidemiology Program, funded by the NationalInstitutes of Health. Researchers identified patients with late-onsetdiabetes in Rochester, Minn., between 1960 and 1995 and followedthem for three years to see who developed pancreatic cancer.
Investigators found 1,920new diabetes cases in people age 50 and older. Of those, 21 developedpancreatic cancer within three years. Based on normal nationaldata, Chari said, one would expect to find just two cases insteadof 21. He said the diabetes-pancreatic cancer link was even morepronounced in patients in their 70s.
Dr. Emmet Keeffe, chairmanof Digestive Disease Week and chief of hepatology at StanfordUniversity Medicine Center in Palo Alto, Calif., told UPI, "Thissounds like an excellent study that confirms hints of this inthe past. It appears to provide scientific strength to clues thatwe've had over the years regarding this relationship."
Physicians will need tobe on notice to begin testing more routinely for pancreatic cancerin cases late-onset diabetes, Keeffe said.
Dr. Cynthia Yoshida, ofthe University of Virginia Digestive Health Center of Excellence,told UPI, "most clinicians knew this intuitively," butthe study added a critical time and age element. She noted themean time from diagnosis of diabetes to diagnosis of pancreaticcancer was only 8.7 months, and many of the cases occurred inpeople in their 70s.
That kind of information,Yoshida said, will help physicians remain alert to the possibilityof pancreatic cancer in that age group whenever they see a newcase of diabetes.