Long-term prognosis after endoscopic resection of T1a-MM/T1b-SM1 esophageal squamous cell carcinoma.

The objective of this study was to evaluate the long-term prognosis of T1a-MM/T1b-SM 1 esophageal squamous cell carcinoma (ESCC) after endoscopic resection (ER) and to validate the follow-up policy for pT1a-MM lymphovascular invasion (LVI)-negative ESCC. In this retrospective single-center analysis, patients who underwent ER for superficial ESCC between April 2002 and June 2021 were identified. The overall survival (OS), metastatic recurrence, and recurrence-free survival (RFS) rates were estimated using the Kaplan-Meier method. Cox proportional hazards models for OS, metastatic recurrence, and RFS were used. A total of 104 ESCC patients were eligible for the analysis. Of 104 patients, 81 had pT1a-MM, and 23 had pT1b-SM1. The 5-year OS, RFS, and metastatic recurrence rates of the 56 cases of pT1a-MM LVI-negative ESCC without additional treatment were 0.848 (95% confidence interval [CI]: 0.687-0.931), 0.817 (95% CI: 0.647-0.911), and 0.061 (95% CI: 0.014-0.240), respectively. Cox regression analysis for OS, RFS, and metastatic recurrence showed that only lymphatic invasion was strongly associated with metastatic recurrence (adjusted hazard ratio, 10.3; 95% CI: 2.01-53.3; P = .005). The proportion of deaths from other diseases was considerably higher (17/104, 16.3%) than that from ESCC (2/104, 1.9%). This may be related to the high complication rate of malignant tumors in other organs (43.3%, 45/104). The prognosis of ER for pT1a-MM and LVI-negative ESCC is good, and the follow-up policy is valid. Malignant tumors in other organs may be a major prognostic factor for superficial ESCC after ER.