The role of postoperative radiotherapy for radically resected esophageal squamous cell carcinoma: a systemic review and meta-analysis.

backgroundThe role of postoperative radiotherapy (PORT) for radical resected esophageal squamous cell carcinoma (ESCC) remains controversial. This meta-analysis aims to determine whether PORT achieves survival benefit compared with surgery alone (S alone) for radically resected ESCC.

methodsThe PubMed, EMBASE, Web of Science, and Cochrane Library were searched for relevant articles. The primary endpoints were overall survival (OS) and disease-free survival (DFS), reported as hazard ratios (HR) and 95% confidence intervals (CIs).

resultsSix randomized trials and 13 retrospective studies that included a total of 8,198 patients were eligible. PORT provided significant OS benefit compared with S alone in retrospective studies (HR =0.75, 95% CI: 0.65-0.85), but not in randomized controlled trials (RCTs) (HR =0.94, 95% CI: 0.81-1.09). PORT was associated with significantly improved DFS and obvious reduction in the risk of locoregional recurrence compared to S alone in either retrospective studies or RCTs. In the subgroup analysis for retrospective studies, PORT gained superior OS in patients with lymph node-positive (pN+), patients with lymph node-negative (pN0) or pT2-3N0, PORT with three-dimensional radiotherapy (3D-RT), PORT with chemotherapy, and patients with R0 resection, respectively.

conclusionsThe present study shows that PORT can improve DFS and decrease risk of locoregional recurrence in patients with radically resected ESCC, and PORT using 3D-RT or in combination with chemotherapy is likely to be more useful. Further well-designed, prospective studies are needed to confirm the effect of PORT on OS.