Li J, Wen Y, Xiang Z, Du H, Geng L, Yang X, Zhang Y, Bai J, Dai T, Feng G, Liu L, and Du X
Background and Purpose: This study aimed to evaluate the efficacy of radical radiotherapy and assess prognostic factors in metachronous oligometastatic esophageal cancer (MOEC) patients after initial treatment with curative-intent surgery and/or chemoradiotherapy., Materials and Methods: MOEC Patients during 2009-2018 in Mianyang Central Hospital were retrospectively analyzed. Each patient had ≤5 oligometastatic lesions, and the primary lesions were controlled in this study. Patients were devided into radiotherapy (RT) and non-radiotherapy (NRT) groups. The study endpoints were overall survival (OS) and treatment toxicities., Results: This study included 82 patients who underwent intensity-modulated radiotherapy for MOEC. Median OS were 14 (95% confidence interval [CI], 11.0-17.0) and 7 (95% CI, 4.5-9.5) months for the RT and NRT groups, respectively (P = 0.016). Median OS were 18 (95% CI, 13.6-22.4) and 10 (95% CI, 5.1-14.9) months for lung and bone metastases, respectively (P = 0.010). Median OS were 15 (95% CI, 12.4-17.6) and 10 (95% CI, 7.6-12.4) months for interval time from initial diagnosis to metastasis ≥12 and <12 months, respectively (P = 0.026). Median OS were 16 (95% CI, 12.2-19.8) and 10 (95% CI, 5.0-15.0) months for biological effective dose (BED 10 ) ≥ 60 Gy and BED 10 < 60 Gy, respectively (P = 0.033). Cox multivariate regression analysis showed that treatment modality (RT vs. NRT) was an independent prognostic factor for MOEC patients (hazard ratio: 1.8, 95% CI: 1.1-3.0; P = 0.022). No toxic side effects greater than grade 3 were observed in all patients., Conclusions: Radiotherapy is a feasible and positive treatment for MOEC patients after initial treatment, a radical radiation dose with BED 10 ≥ 60 Gy has benefits in extending survival. Radical radiotherapy should thus be considered for MOEC patients., Competing Interests: Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)