After much debate, adjuvant
therapy has become the standard of care worldwide for resected localized
gastric cancer. However, geographic differences exist in standard adjuvant treatments: postoperative chemoradiation in North America, perioperative
chemotherapy in the United Kingdom, and postoperative
chemotherapy in East Asia. Now that D2
gastrectomy has been recognized as the optimal surgery for localized
gastric cancer in the West as well as in Asia, the standard adjuvant treatments used in the West may need to be reconsidered. One of the most important issues in adjuvant
therapy for localized
gastric cancer is how to improve the clinical outcomes of current standard treatments. Recent
Cancer and
Leukemia Group B (CALGB) and AMC studies suggest that simply intensifying
chemotherapy by adding more agents or prolonging
treatment duration is insufficient. However, new strategies like early initiation of
chemotherapy and/or intraperitoneal
chemotherapy may further improve the current standard adjuvant
therapy. In the era of targeted
therapy, the role of
biologic agents for
gastric cancer should also be explored in the adjuvant setting. With a deeper understanding of the molecular biology of
gastric cancer, adjuvant
therapy for patients with localized
gastric cancer can be optimized and individualized.