Additional Treatment Following Noncurative Endoscopic Resection for Esophageal Squamous Cell Carcinoma: A Comparison of Outcomes between Esophagectomy and Chemoradiotherapy

Background Endoscopic resection (ER) has been widely implemented for cT1N0 esophageal squamous cell carcinoma (ESCC). Additional therapy, including esophagectomy and chemoradiotherapy (CRT), is sometimes required after noncurative ER. Methods We retrospectively reviewed 108 patients who received any additional treatment following noncurative ER (positive vertical margins, lymphovascular invasion, or invasion depth of submucosa or more), and compared the short- and long-term outcomes between the two treatment modalities. Results Of 108 patients, 56 underwent esophagectomy (E group), and 52 received CRT (CRT group). A positive vertical margin was observed in 17 (14.8%) patients and high risks of occult lymph node metastasis were observed in 91 (85.2%) patients, as well as lymphovascular invasion in 35 (32.4%) patients, invasion depth of the submucosa or more in 27 (25.0%) patients, and both in 29 (26.9%) patients. The E group patients were significantly younger ( p = 0.046) and tended to present with larger tumors than those in the CRT group ( p = 0.057). Lymphatic invasion was more frequent in the E group ( p = 0.019), and, furthermore, one treatment-related death was observed in the E group. There were no significant differences between the groups in overall and disease-specific survival ( p = 0.406 and 0.151, respectively), however, recurrence was only observed in the CRT group. Conclusion Both esophagectomy and CRT are safe and effective as additional treatments after noncurative ER in patients with ESCC. Esophagectomy is oncologically safe, whereas a risk of postoperative morbidity and mortality remains. Although the adverse events are acceptable, CRT has a certain degree of risk of disease recurrence.