Investigators in Europe evaluated the role of preoperative and postoperative chemotherapy without radiation therapy. In the randomized phase III trial (MRC-ST02), patients with stage II or higher adenocarcinoma of the stomach or of the lower third of the esophagus were assigned to receive three cycles of epirubicin, cisplatin, and continuous infusion fluorouracil (ECF) before and after surgery or to receive surgery alone. Compared with the surgery group, the perioperative chemotherapy group had a significantly higher likelihood of progression-free survival (hazard ratio [HR] for progression, 0.66; 95% confidence interval [CI], 0.53–0.81; P < .001) and of OS (HR for death, 0.75; 95% CI, 0.60–0.93; P = .009). Five-year OS was 36.3%, 95% CI, 29 to 43 for the perioperative chemotherapy group and 23%, 95% CI, 16.6 to 29.4 for the surgery group.[Level of evidence: 1iiA]
Japanese investigators randomly assigned 1,059 patients with stage II or III gastric cancer who had undergone a D2 gastrectomy to receive either 1 year of S-1, an oral fluoropyrimidine not available in the United States, or follow-up after surgery alone. Patients were randomly assigned in a 1:1 fashion. The 3-year OS rate was 80.1% in the S-1 group and 70.1% in the surgery-only group. The HR for death in the S-1 group, as compared with the surgery-only group, was 0.68 (95% CI, 0.52–0.87; P = .003).[Level of evidence: 1iiA]
Subsequently, investigators in Asia evaluated the role of capecitabine/oxaliplatin as adjuvant therapy after gastric cancer resection. In the CLASSIC trial (NCT00411229), 37 centers in South Korea, China, and Taiwan randomly assigned 1,035 patients with stage IIA, IIB, IIIA, or IIIB gastric cancer who had undergone a curative D2 gastrectomy to receive adjuvant chemotherapy (eight 3-week cycles of capecitabine plus oxaliplatin) or follow-up post-surgery alone. The 3-year disease-free survival rate was 74% in the chemotherapy group and 59% in the surgery-alone group (HR, 0.56; 95% CI, 0.44–0.72; P < .0001). The 3-year OS was 83% in the chemotherapy group and 78% in the surgery-alone group (HR, 0.72; 95% CI, 0.52–1.00; P = .0493).[Level of evidence: 1iiA] Further follow-up is anticipated.