To evaluate the efficacy of postoperative radiotherapy (PORT) compared with surgery alone in terms of survival outcomes and toxicity in patients with radically resected esophageal squamous cell carcinoma (ESCC).
Approach:
Literature Search: A systematic search was performed in PubMed, EMBASE, and the Cochrane Library from January 1990 to June 2025 for randomized controlled trials (RCTs) and retrospective studies (RSs) comparing PORT versus surgery alone.
Data Extraction: Data were independently extracted by two investigators, focusing on overall survival (OS), disease-free survival (DFS), locoregional recurrence (LRR), distant metastasis (DM), and treatment toxicity.
Quality Assessment: Quality was assessed using the revised Cochrane risk-of-bias tool for RCTs and the Newcastle-Ottawa Scale for retrospective studies.
Key Findings:
PORT significantly improved overall survival (OS) with HR = 0.74 (95% CI: 0.69–0.80, P < 0.001) compared to surgery alone.
PORT significantly improved disease-free survival (DFS) with HR = 0.62 (95% CI: 0.58–0.67, P < 0.001) compared to surgery alone.
PORT significantly reduced locoregional recurrence (LRR) with OR = 0.30 (95% CI: 0.27–0.34, P < 0.001) but had no effect on distant metastasis (DM) with OR = 1.01 (95% CI: 0.92–1.11, P = 0.85).
Subgroup analyses indicated that PORT improved OS in patients with positive lymph nodes (HR = 0.65), T3-4 stage (HR = 0.72), R0 resection (HR = 0.72), and those receiving modern radiotherapy (HR = 0.67).
The addition of chemotherapy yielded the greatest OS benefit (HR = 0.55).
PORT was associated with a higher incidence of grade ≥3 acute toxicity (OR = 2.45, 95% CI: 1.89–3.18, P < 0.001), primarily radiation esophagitis and leukopenia.
Interpretation:
For patients with radically resected ESCC, PORT significantly improves OS and DFS and reduces LRR, particularly in high-risk patients.
Limitations:
The meta-analysis included studies with varying quality and design, which may affect the reliability of the results.
Potential publication bias and heterogeneity among studies may influence the findings.
Conclusion:
PORT significantly improves OS and DFS and reduces LRR in patients with radically resected ESCC, although it is associated with increased acute toxicity.
