The survival benefit of oxaliplatin-based adjuvant chemotherapy, improving over time and with the disease severity, was confirmed at 10 years in patients with stage 2 to 3 colon cancer, a new study published online ahead of print in the Journal of Clinical Oncology has shown.1

The MOSAIC study evaluated adjuvant FOLFOX4 (oxaliplatin, fluorouracil, leucovorin) in patients with stage 2 to 3 resected colon cancer.

Results showed that 3-year disease-free survival and 6-year overall survival were improved with adjuvant oxaliplatin. In this analysis, researchers present 10-year overall survival data and overall survival and disease-free survival by mismatch repair (MMR) status and BRAF mutation status.

Continue Reading

Researchers analyzed survival data after 10 years of follow-up for 2246 patients and assessed MMR status and BRAF mutation status in 1008 samples.

Results showed that after a median follow-up of 9.5 years, the 10-year overall survival rates in the LV5FU2 (bolus/infusion fluorouracil plus leucovorin) and FOLFOX4 arms were 67.1% and 71.7%, respectively (HR, 0.85; P = .043) in the entire population.

Overall survival rates for patients with stage 2 colon cancer were 79.5% vs 78.4% for LV5FU2 and FOLFOX, respectively (HR, 1.00; P = .980), and 59.0% vs 67.1%, respectively, for those with stage 3 disease (HR, 0.80; P = .016).

Researchers found that having MMR-deficient (dMMR) tumors was an independent prognostic factor (HR, 2.02; 95% CI, 1.15 – 3.55; P = .014), but BRAF mutation was not prognostic for overall survival (P = .965). The analysis also demonstrated an overall survival benefit and disease-free survival benefit with adjuvant FOLFOX in those with dMMR tumors or BRAF mutation.

RELATED: Adjuvant Chemo for Colon Cancer Should Be Initiated Within 8 Weeks of Surgery

“These updated results support the use of FOLFOX in patients with stage 3 disease, including those with dMMR or BRAF mutation,” the authors conclude.

Reference

  1. André T, de Gramont A, Vernerey D, et al. Adjuvant fluorouracil, leucovorin, and oxaliplatin in stage II to III colon cancer: updated 10-year survival and outcomes according to BRAF mutation and mismatch repair status of the MOSAIC study [published online ahead of print November 2, 2015]. J Clin Oncol. doi: 10.1200/JCO.2015.63.4238.

Topics:

Colon Cancer Gastrointestinal Cancer