Treatment Option Overview
Radical surgery represents the standard form of therapy that has curative intent. However, the incidences of local failure in the tumor bed and regional lymph nodes, and distant failures via hematogenous or peritoneal routes, remain high. As such, adjuvant external-beam radiation therapy with combined chemotherapy has been evaluated in the United States.
In a phase III Intergroup trial (SWOG-9008), 556 patients with completely resected stage IB to stage IV (M0) adenocarcinoma of the stomach and gastroesophageal junction were randomly assigned to receive surgery alone or surgery plus postoperative chemotherapy (5-fluorouracil [5-FU] and leucovorin) and concurrent radiation therapy (45 Gy). With 5 years' median follow-up, a significant survival benefit was reported for patients who received adjuvant combined modality therapy.[Level of evidence: 1iiA] Median survival was 36 months for the adjuvant chemoradiation therapy group as compared to 27 months for the surgery-alone arm (P = .005). Three-year overall survival (OS) rates and relapse-free survival rates were 50% and 48%, respectively, with adjuvant chemoradiation therapy versus 41% and 31%, respectively, for surgery alone (P = .005). The rate of distant metastases was 18% for the surgery-alone arm and 33% for the chemoradiation-therapy arm. Because distant disease remains a significant concern, the aim of the Cancer and Leukemia Group B study (CALGB-80101) was to augment the postoperative chemoradiation regimen used in INT-0116. Neoadjuvant chemoradiation therapy such as in the RTOG-9904 trial, which is now completed, and the SWOG-S0425 (NCT00335959) trial, which is now closed, was clinically evaluated.
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 5-FU 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]
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