Song M, et al. - Whether the benefit of marine omega-3 polyunsaturated fatty acids (MO3PUFAs) on survival of colon cancer differs by tumor molecular subtype was investigated by analyzing data from a phase 3 randomized trial of FOLFOX or FOLFOX + cetuximab among 1,735 stage III colon cancer patients. The link between MO3PUFA and disease-free survival (DFS) and overall survival according to KRAS and BRAF^V600E mutations and DNA mismatch repair (MMR) status was determined by calculating multivariable hazard ratios and 95% confidence intervals (CIs). With higher MO3PUFA intake, improved 3-year DFS for KRAS-wildtype tumors (77% vs 73%; HR, 0.84, 95% CI, 0.67-1.05) as well as better 3-year DFS for tumors with deficient MMR (72% vs 67%) was found. No heterogeneity was found by BRAF^V600E mutation. For overall survival, the findings were similar. Overall, higher MO3PUFA intake was suggested to be related to improved survival among stage III colon cancer patients with wildtype KRAS and deficient MMR.