NEW YORK (GenomeWeb News) — The American Society of Clinical Oncology is advising doctors treating colorectal cancer patients to test for a variant of the KRAS gene that may predict poor response to available treatments.
ASCO this week offered its preliminary recommendation based on recent studies concerning genetic testing for KRAS mutations, and the effectiveness and cost of the drugs cetuximab (marketed as Erbitux) and panitumumab (marketed as Vectibix), which are based on anti-EGFR antibodies.
If a patient has a mutated form of the KRAS gene, ASCO recommends against anti-EGFR antibody therapy because recent studies suggest it is effective only in people with the normal form of the gene.
As many as 40 percent of colon cancer patients have the KRAS mutation, ASCO said in its provisional clinical opinion. ASCO also said that routine testing for KRAS mutations in patients with metastatic colorectal cancer could save the US health system up to $604 million per year from the cost of the drug cetuximab alone.
"Basing cancer treatment on the unique genetic characteristics of the tumor or the individual with cancer will improve patient outcomes and help avoid unnecessary costs and side effects for patients who are unlikely to benefit," ASCO President Richard Schilsky said in a statement.
Using KRAS testing to guide colorectal cancer treatment is a prime example of where cancer care is heading," Schilsky added.
ASCO said its opinion paper will be published in the upcoming Journal of Clinical Oncology.