The incidence of early-stage esophageal cancer (EC) is increasing rapidly and even accounting for approximately 40% of esophageal squamous cell carcinoma. Endoscopic Resection (ER) is a crucial therapeutic and diagnostic method for superficial esophageal cancer. However, lymph node metastasis rate in pT1b patients is relatively high, and additional treatment is recommended after ER.~Adjuvant chemoradiotherapy is a treatment option and has already been proven to be equivalent to radical surgery. However, limited studies, with relatively small sample size and nature of low-level evidence, consistently showed that additional adjuvant radiotherapy failed to improve survival. Hence, adjuvant radiotherapy should not be applied without selection.~T1b EC patients are a heterogeneous population, with reported regional metastasis or recurrence rates varying considerably from 0-53% in SM1 disease, 19-31% in SM2, and 36-61% in SM3. The risk factors of regional metastasis or recurrence were also reported, generally including lymphovascular invasion (LVI) and pT1b disease.~In view of the aforementioned evidence, we hypothesized that selective adjuvant radiotherapy based on risk factors might significantly improve survival. The aim of this study was to evaluate the efficacy of adjuvant radiotherapy after ESD for pT1b EC and further explore the potential population who could benefit.
Endoscopic Resection (ER) is a crucial therapeutic and diagnostic method for superficial esophageal cancer. However, lymph node metastasis rate in pT1b patients is relatively high. Although, adjuavnt chemoradiotherapy is recommended, limied studies prove the superiority of additional adjuvant radiotherapy over ESD alone. This study aimed to further verify the efficacy of adjuvant radiotherapy in early-stage esophageal cancer after ESD.