Efficacy and safety of re-irradiation for locoregional esophageal squamous cell carcinoma recurrence after radiotherapy: a systematic review and meta-analysis

Abstract

Background: There is currently no standard treatment for locoregional recurrence of esophageal squamous cell carcinoma (ESCC) previously treated with radiotherapy. This study aimed to assess the efficacy and safety of re-irradiation for ESCC patients with locoregional recurrence. Methods: The PubMed, EmBase, and Cochrane library databases were systematically searched for eligible studies published before January 2021. The pooled effect estimates were calculated using the random effects model. Subgroup analyses were conducted to assess the treatment effectiveness of re-irradiation based on specific characteristics. Results: Nine retrospective studies including 573 ESCC patients with locoregional recurrence were selected. The pooled incidences of the 1-year, 2-year, 3-year, and 5-year survival for patients after re-irradiation were 59% (95% confidence interval [CI]: 35–83; P < 0.001), 25% (95% CI: 16–33; P < 0.001), 25% (95% CI: 4–45; P = 0.017), and 15% (95% CI: 2–27; P = 0.024), respectively. The rates of complete response and local re-recurrence after re-irradiation were 54% (95% CI: 21–88; P = 0.001) and 62% (95% CI: 55–70; P < 0.001), respectively. The median overall survival and local failure-free survival for patients after re-irradiation were 13.94 months (95% CI: 4.18–46.51; P < 0.001) and 11.01 months (95% CI: 5.99–20.22; P < 0.001), respectively. Grade ≥ 3 adverse events of esophageal perforation, tracheoesophageal fistula, and radiation pneumonitis were significantly more common after re-irradiation. Conclusions: This study found that re-irradiation for ESCC patients with locoregional recurrence after previous radiotherapy was feasible. However, patients should be carefully observed in order to treat associated adverse events, including esophageal perforation, tracheoesophageal fistula, and radiation pneumonitis.