Radiotherapy for Anastomotic Recurrence and Regional Lymph Node Metastases after Esophagectomy for Esophageal Cancer: Current Evidence and Open Questions

Surgery remains the mainstay of curative treatment for localized esophageal cancer, yet a substantial proportion of patients relapse after esophagectomy, most often at the anastomosis or in the regional lymph nodes. For these patients, who are frequently unfit for further surgery, radiotherapy is the principal locoregional option, but the evidence base is thin and largely retrospective. This review summarizes current knowledge on the patterns and determinants of postoperative recurrence, the diagnostic work-up required before salvage treatment, and the radiotherapy strategies available for anastomotic recurrence and regional nodal disease. The roles of conventional external-beam radiotherapy, intensity-modulated radiotherapy, stereotactic body radiotherapy and particle therapy are compared, with particular attention to dose constraints in the re-irradiation setting. The toxicity–efficacy balance and the biological mechanisms underlying radioresistance are then considered; how best to combine radiotherapy with systemic agents, including immune-checkpoint blockade, remains an open question. Because prospective data specific to this setting remain scarce, treatment decisions still rest on individualized, multidisciplinary assessment.