WASHINGTON (Reuters) - Researchers reported on Wednesday they could detect even early stage pancreatic cancer by shining light on a neighboring organ.
The findings may lead to the first method to detect this particularly deadly form of cancer early enough to treat it, said study researcher Vadim Backman of Northwestern University. Pancreatic cancer is the fourth-leading cause of U.S. cancer deaths.
Backman and colleagues analyzed light patterns they reflected off the lining of the duodenum, a part of the digestive tract next to the pancreas, they wrote in the journal Clinical Cancer Research.
They were able to distinguish nearly all of the 19 early and late-stage cancer patients from 32 healthy volunteers based on slight molecular changes revealed by the light patterns.
Those 51 tissue samples looked the same under a regular microscope, they said.
Pancreatic cancer is usually symptom-free in its early stages. The five-year survival rate for the disease is only 5 percent, and most die within a year of diagnosis, in part because it is so difficult to detect.
“(Screening techniques like) MRI are just not sensitive to pancreatic lesions (tumors) at a stage when pancreatic cancer is curable,” Backman said in a telephone interview.
Removing and testing tissue from the pancreas itself comes with a 20 percent chance of serious complications, so it is done only in patients who already have symptoms. And by that point, said Backman, “It’s too late to treat.”
This new method would leave the pancreas untouched.
Doctors might start by using it on high-risk populations -- including smokers and people with family histories of the cancer -- before they show signs of illness, Backman said.
But there is a lot more to prove before these findings make it to the clinic, added Dr. Kenneth Hung of Harvard University, who was not involved in the research.
For one thing, the method is based on a controversial idea: that cells surrounding a cancer site will have some of the molecular changes found in the tumor itself, Hung said in a telephone interview.
Hung added that what worked in this small study may be difficult to reproduce for wide-scale testing.
Still, Hung said, “anything that we can find to enhance the earlier diagnosis of pancreatic cancer would definitely be of great value.”
The researchers extracted the tissue samples using endoscopy -- a routine exploratory procedure that at least a million Americans undergo each year, Backman said.
He and colleagues already have tried this strategy to screen for colon cancer, finding the same light patterns in the rectum, and they are now starting to have similar successes with breast and lung cancer screening, Backman said.
More than 33,000 Americans will die from pancreatic cancer this year, according to the American Cancer Society.