Long‐Term Outcomes of Surveillance Endoscopy After Endoscopic Resection for Early Esophageal Squamous Cell Carcinoma: A Multicenter Retrospective Study

BACKGROUND: Endoscopic surveillance is mandatory for patients who underwent endoscopic resection (ER) for esophageal squamous cell carcinoma (ESCC) to detect multiple ESCCs. This study aimed to evaluate whether the current surveillance system is appropriate from the viewpoint of the clinical course after ER. METHODS: This was a retrospective study conducted at a multicenter, high-volume center. Patients who underwent ER without additional therapy for ESCC with T1a pathology were included. The primary endpoints were the 3- and 5-year cumulative incidence of ESCC with invasion depth of the muscularis mucosa or deeper (index ESCC). RESULTS: A total of 378 patients were included in this analysis. The median observation period was 67.3 (range 24.1-104.3) months. In total, 375 patients underwent surveillance endoscopy with narrow band imaging (NBI), followed by Lugol chromoendoscopy (LCE). The numbers of patients with surveillance intervals of 6 months, 12 months, and irregular were 180, 133, and 65, respectively. There were 275 cases of multiple ESCCs, including 11 index ESCCs. The 3- and 5-year cumulative incidence rates of index ESCCs were 1.3% and 2.7%, respectively. Multiple ESCCs were diagnosed with higher Lugol voiding lesion grades and during 6-month rather than 12-month or irregular surveillance (p < 0.001). However, cox proportional hazards analysis showed no significant factors associated with the cumulative incidence of index ESCCs. No ESCC-related death occurred during the study period. CONCLUSION: Surveillance endoscopy with NBI and LCE at intervals of 6-12 months can be acceptable, given the low cumulative incidence of index ESCCs and favorable prognosis.