Adjuvant chemotherapy for colon cancer: the difference between Japanese and western strategies

Colorectal cancer (CRC) is the third most common cancer in the western world and also in Japan. The key factors in curing CRC are early detection, surgery and adequate adjuvant chemotherapy if needed.

Based on the results of following pivotal adjuvant trials, FOLFOX or XELOX are considered standard adjuvant chemotherapy for patients with stage III colon cancer in the western countries. On the other hand, 5-FU based monotherapies showed favorable results as adjuvant chemotherapy in Japan providing comparable results to doublet strategies in the western countries. There are two key factors that could provide better outcome: D3 lymph node dissection (LND) and thorough pathological examinations.

I believe that oxaliplatin based adjuvant chemotherapy may not be suitable for at least substage IIIA patients who underwent D3 surgery and were diagnosed by thorough pathological examinations for the following two reasons: toxicities and strongly stage-dependent added benefit of oxaliplatin in overall survival. We are awaiting the final results of three Japanese ongoing trials focusing on oxaliplatin based adjuvant chemotherapy. These results will hopefully help us create and implement global guidelines for truly standardizing the management of colon cancer prevalent all over the world, and help physicians recommend the treatment strategy available to each patient.