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. Discrepancies between Japanese D3 dissection and the CME with CVL principle persist, with variations
in longitudinal margins and recommended procedures. Non-randomized trials indicate the superiority of D3 over D2,
but a consensus is lacking.

This prospective, international, multicenter, randomized controlled trial employs a two-arm, parallel-group,
open-label design to rigorously compare the 5-year overall survival outcomes between D2 and D3 lymph node
dissection in stage II-III right colon cancer. Building on prior studies, the trial aims to address existing knowledge
gaps and provide a comprehensive evaluation of the outcomes associated with D3 dissection. The study population
comprises patients with right colon cancer, ensuring a focused investigation into the specific context of this disease.
The trial design emphasizes its global scope and collaboration across multiple centers, enhancing the generalizability
of the findings.

This study’s primary objective is to elucidate the potential superiority in 5-year overall survival benefits
of D3 lymph node dissection compared to the conventional D2 approach in patients with stage II-III right colon
cancer. By examining this specific subset of patients, the research aims to contribute valuable insights into optimizing
surgical strategies for improved long-term outcomes. The trial’s international and multicenter nature enhances
its applicability across diverse populations. The outcomes of this study may inform future guidelines and contribute
to the ongoing discourse surrounding the standardization of colon cancer surgery, particularly in the context of right
colon cancer.