Charles Fuchs, MD: RAS Mutations in Metastatic Colorectal Cancer

About what percent of patients with metastatic CRC harbor RAS mutations?

As I say now with extended RAS testing, whereas we used to think maybe 35% of patients harbor a RAS mutation when we did just EXON 2 KRAS mutations, we now know that when you extend to all KRAS mutations and all NRAS mutations, 50% of patients harbor a mutation. In fact, one of the most recent analyses showed that 52% of patients have a RAS mutation, such that perhaps even more than half are patients who harbor that mutation for whom you don't want to give that antibody.

Unresectable Colon Cancer: Case 2

52-year-old woman newly diagnosed with metastatic CRC and is genotyped as part of her initial work up.