Current approaches to gastric cancer in Korea.

Gastric cancer remains a significant global health problem and is the most common cancer in Korea. Surgery is the only curative treatment for localized gastric cancer, but most cases present at an advanced stage. The proportion of early gastric cancer and the incidence of gastric cancer located in the upper third of the stomach have increased in Korea. The majority of patients in Korea receive surgery alone or surgery plus chemotherapy. Over 50% of the surgeries have been performed in five major hospitals, with most surgeons performing extended lymph node dissection (D2 or D3). The 5-year survival rate with curative resection is 55.6%-66.0%, with rates of 92.9%-98.0%, 84.2%-92.0%, 69.3%-72.0%, 45.8%-54.0%, 29.6%-36.5%, and 9.2%-23.9% according to TNM stages of Ia, Ib, II, IIIa, IIIb, and IV, respectively. Although convincing phase III data are lacking, postoperative immunochemotherapy with 5-fluorouracil (5-FU) plus mitomycin for 2 months followed by OK-432 plus doxifluridine for 24 months has been widely used in Korea. A phase III trial of adjuvant capecitabine/oxaliplatin is ongoing in curatively resected disease (CLASSIC study). The modified 5-FU/cisplatin regimen has become popular since the mid 90s, and various combinations including taxanes, oral 5-FU prodrugs, oxaliplatin, and irinotecan have been evaluated. Recently, Korean investigators have played pivotal roles in studies initiated by global pharmaceutical companies, and the Korean Cancer Study Group has initiated 14 multicenter trials, including phase III trials in gastric cancer and international cooperative trials. Future international cooperative trials are anticipated.