Genetic Clues to Cancer Risk From GERD
Researchers Use Genetic Markers to Identify GERD Patients at Risk for Esophageal Cancer
Gene Testing and Colon Cancer Treatment
Obel also announced new ASCO guidelines recommending that people with metastatic colorectal cancer be tested for KRAS gene mutations before undergoing treatment with the targeted drugs Erbitux and Vectibix.
Studies have demonstrated that only patients whose tumors have the normal form of the KRAS gene respond to treatment with the drugs. It is estimated that 40% of colon cancer patients have KRAS gene mutations and will not benefit, Obel says.
Weeding out people who will not benefit from Erbitux and Vectibix will result in significant cost savings to the health care system while sparing patients from side effects of ineffective therapy, Obel tells WebMD.
An economic analysis being presented at the meeting found that routine testing for KRAS gene mutations in patients with metastatic colorectal cancer could save the U.S. health system up to $604 million per year in the cost of Erbitux alone.
Genes Predict Response to Pancreatic Cancer Treatment
In a third study being presented at the symposium, researchers found that certain genetic variations may help predict whether people with pancreatic cancer will respond to treatment.
The researchers examined 15 variants in eight genes involved in repairing DNA damage caused by cancer treatment.
They found that 94% of pancreatic cancer patients with "good" gene variants responded to treatment with radiation and the chemotherapy drug Gemzar, compared with only 73% of people with "bad" gene variants.
People with good gene variants also lived longer. They survived a median of 25.5 months vs. 7.4 months for the "bad" genotype carriers, says Donghui Li, PhD, of the University of Texas M.D. Anderson Cancer Center in Houston.
Taken together, all "the studies bring us closer to the goal of distinguishing those patients most likely to benefit from screening and treatment from those who will not," Obel says.