Optimal duration of adjuvant therapy for stage III colon cancer

Colon cancer remains a major cause of mortality worldwide. Following adequate surgical resection of lymph node-positive colon cancer, the standard of care since 2004 has been to administer an oxaliplatin-containing regimen (eg, FOLFOX or CAPOX) for 6 months. These regimens have consistently improved oncologic outcomes compared with non-oxaliplatin therapies in multiple adjuvant randomized controlled trials. However, oxaliplatin-induced cumulative dose-dependent neurotoxicity is a major cause of morbidity that can persist years after treatment. The IDEA collaboration is a study that pooled data from 6 concurrent phase 3 trials comparing 3 vs 6 months of adjuvant FOLFOX or CAPOX to evaluate whether a shorter duration of therapy could maintain efficacy while reducing neurotoxicity. In this article, we review the history of adjuvant therapy in stage III colon cancer and comprehensively detail the results of the IDEA collaboration. A risk-based approach focusing on efficacy, toxicity, and patient selection is emphasized to guide discussions regarding the optimal duration of adjuvant therapy in stage III colon cancer.