(HealthDay News) — Adding cetuximab to adjuvant chemotherapy does not improve disease-free survival in stage III colon cancer patients following surgical resection, according to a study published in the April 4 issue of the Journal of the American Medical Association.
Steven R. Alberts, M.D., of the Mayo Clinic in Rochester, Minn., and colleagues conducted a randomized trial of 2,686 stage III patients with colon cancer, aged 18 years or older, enrolled following resection. Patients were randomized to 12 biweekly cycles of the modified sixth version of the leucovorin, fluorouracil, and oxaliplatin (mFOLFOX6) regimen, with and without cetuximab. KRAS mutation status was centrally determined.
Over a median follow-up of 28 months, the researchers found no benefit to adding cetuximab. Three-year disease-free survival was similar for mFOLFOX6 alone and for mFOLFOX6 with cetuximab for patients with wild-type KRAS (74.6 and 71.5 percent, respectively; hazard ratio [HR], 1.21; P = 0.08) and for those with mutated KRAS (67.1 and 65.0 percent, respectively; HR, 1.12; P = 0.38). There was no significant benefit in any of the subgroups assessed. Among all patients, those on cetuximab experienced significantly more grade 3 or higher adverse events (72.5 versus 52.3 percent; odds ratio [OR], 2.4) and increased failure to complete 12 cycles (33 versus 23 percent; OR, 1.6). For patients aged 70 years or older, increased toxicity and greater detrimental differences in all outcomes were seen.
“Among patients with stage III resected colon cancer, the use of cetuximab with adjuvant mFOLFOX6 compared with mFOLFOX6 alone did not result in improved disease-free survival,” the authors write.
Several authors disclosed financial ties to biopharmaceutical companies, including Bristol-Myers Squibb, ImClone, Sanofi Aventis, and Pfizer, all of which funded the trial.