Are 12 nodes needed to accurately stage T1 and T2 colon cancers?

Evaluation of 12 lymph nodes has been mandated to prevent colon cancer understaging. Given that the probability of node metastases is largely associated with T-stage, are <12 nodes substandard for T1 and T2 lesions? We evaluated if survival for T1 and T2 tumors varies by nodes examined. In SEER, 61,237 patients undergoing colon cancer resection were identified. For each T-stage, 5-year survival rates were compared for node-negative cancers by using stepwise node cut-point comparisons (4 nodes, <4, etc.). Survival impact was determined by log-rank test and hazard regression. For T1 tumors, 4 nodes had 24% lower hazard of death compared to <4. For T2 tumors, 10 nodes had the biggest survival impact, 15% lower hazard of death. In conclusion, the number of nodes to stage T1 and T2 lesions may be <12.