Researchers Zero In on GI Cancers

ByABC News
January 14, 2009, 7:32 PM

Jan. 15 -- WEDNESDAY, Jan. 14 (HealthDay News) -- New research may one day help physicians identify those patients with gastrointestinal cancers who are most likely to benefit from certain treatments.

The discoveries, paving the way toward an era of personalized medicine, could save the U.S. health-care system millions while sparing patients the agony of receiving treatments that aren't going to help them.

"These are a diverse group of tumors," said Dr. Jennifer C. Obel, an attending physician at NorthShore University Health System in Illinois, who moderated a Tuesday teleconference on the findings. "More than 270,000 people are diagnosed with GI [gastrointestinal] malignancies in the U.S. every year, and about 135,000 succumb to these illnesses on a yearly basis. How do we distinguish those patients most likely to benefit from treatment and screening than those who are not?"

The findings come from four studies being highlighted at the sixth annual Gastrointestinal Cancers Symposium, in San Francisco.

Gastrointestinal cancers are those that affect the esophagus, stomach, pancreas, liver, small intestines, colon, rectum and anus.

A first study found that testing patients with metastatic colorectal cancer for a specific gene mutation which affects how they respond to therapy, then treating accordingly, could save the U.S. health-care system up to $604 million a year.

The analysis follows on earlier research which found that the monoclonal antibody Erbitux (cetuximab) was only effective in patients who have the normal -- not the mutated -- form of the KRAS gene.

The study authors plugged incidence data on colorectal cancer into an economic model and found that testing for KRAS status in all newly diagnosed patients would cost $13 million, while unnecessarily treating those with mutant KRAS genes would cost $617 million, resulting in a net savings of $604 million.

The study was led by Dr. Veena Shankaran, a postdoctoral fellow at the Veterans Administration Center for the Management of Complex Chronic Care and Northwestern University's Robert H. Lurie Comprehensive Cancer Center in Chicago. It was funded by ImClone Systems Inc., which makes Erbitux.