Comparison of D2 vs D3 lymph node dissection for RIght COloN cancer (RICON): study protocol for an international multicenter open-label randomized controlled trial.

Background: Colon cancer is a global health concern, ranking fifth in both new diagnoses and deaths among tumors worldwide. Surgical intervention remains the primary treatment for localized cases, with a historical evolution marked by a focus on short-term outcomes. While Japan pioneered radical tumor removal with a systematic categorization of lymph nodes (D1, D2, D3), the dissemination of Japanese practices to the West was delayed until 90th of last century.