Striving for Consensus: The Application of Existing and Emerging Research Findings to the Practical Management of Gastrointestinal CancersRevised approach to RAS mutation testing in mCRC
1:49 minutes.
TRANSCRIPTION:
DR BENDELL: What I’ve told my folks in the community right now after this data has been published is to say, what this data tells us is that for these patients with the codon 2 KRAS mutations, with the NRAS mutation — so the rarer RAS mutations — we should definitely not give them an anti-EGFR plus oxaliplatin-based therapy. We don’t have a mechanism yet in place to commercially test it. So for right now, for the KRAS wild-type patients, if you’re going to use an anti-EGFR therapy in combination with chemotherapy, until we have that testing in place, to use it with an irinotecan-based regimen. DR LOVE: Charlie? DR FUCHS: Yes. I think the practical thing you want to ask your pathologist is that historically they have been doing codons 12 and 13 exclusively. And what this paper shows is, ask your pathologist, yes, do codons 12 and 13, but also do codon 62 and 146 and NRAS. And if you do that, you’ll probably find out that 50% of your patients have the mutation. DR HECHT: And this has not just been shown in combination with chemotherapy. There was also a retrospective analysis of a single-agent trial, as well, that also shows that patients who have the noncanonical KRAS mutations don’t benefit. So I don’t think it’s just going to be — so if you’re interested in looking, I think, for a single-agent anti-EGFR therapy, I think it’s going to be throughout the whole spectrum of colon cancer that this extra 10% of patients should not get these drugs. DR BENDELL: Right. And I think that eventually these are patients that are not going to benefit. But until we’ve got a way to test it in the community, I think right now, we — DR HECHT: We’re in the 6-month interregnum. DR BENDELL: Exactly. DR HECHT: Mm-hmm. DR BENDELL: Exactly. |