Good IDEA: Drop Adjuvant Chemo From 6 to 3 Months in CRC

John L. Marshall, MD


June 12, 2017

Editorial Collaboration

Medscape &

John Marshall from Medscape, here on the floor at ASCO. I've got my badge and everything; I'm a faculty guy—the whole thing.

Big news yesterday at the plenary session. We were anticipating this. A big piling up of different studies in the stage III colon cancer setting, looking at 6 months versus 3 months [of adjuvant oxaliplatin-based chemotherapy] in a bunch of patients and looking for noninferiority.[1] It is a little bit controversial because, statistically, this compilation of studies didn't meet the noninferiority bar. You saw these curves being presented and you could not put a piece of paper between the 3-month and the 6-month curve. Even though the biostatisticians were suggesting that this might not have met this very high bar statistically, every clinician in that room said that 3 months was as good as 6 months. A standard practice-changing moment.

If you've got patients out there right now who are getting 6 months of adjuvant chemotherapy for colon cancer, you can tell them that all they need is 3 months. No more oxaliplatin nerve toxicity. If you look at the difference between 6 months of nerve toxicity versus 3 months, there's a dramatic difference. In point of fact, most of those patients who went on to 6 months in the clinical trials didn't get all of that oxaliplatin. It is much better to give most of the drug in the 3 months and be done.

Now the subset analysis. T4 N2 cancers had a higher risk overall. Even in that group, there was very little difference between 3 months and 6 months. Many of my colleagues are arguing that in that higher-risk group, you should give patients 3 months of oxaliplatin-based therapy and then maybe 3 months of just fluoropyrimidine. Finally—and I knew this all along and I told you—capecitabine performed better. When they did a subset analysis of those patients who got CAPOX versus FOLFOX, there was an even better outcome.

New standard of care: 3 months of CAPOX chemotherapy for most of your stage III patients. Only in those at higher risk should you consider going to 6 months. In those, I would say use only fluoropyrimidine.

This study changes your practice today. Here at ASCO, John Marshall for Medscape.


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