Endoscopic Surveillance After Endoscopic Resection of Superficial Esophageal Squamous Cell Carcinoma for Metachronous Head and Neck Cancers

BACKGROUND AND AIM: Patients undergoing endoscopic resection (ER) for superficial esophageal squamous cell carcinoma (ESCC) are at risk of developing metachronous head and neck cancers (HNCs). Early detection of HNCs is essential for preserving patients' quality of life. Although periodic endoscopic surveillance for metachronous ESCCs is widely recommended, the optimal strategy for detecting metachronous HNCs after esophageal ER remains unclear. METHODS: This single-center retrospective cohort study included patients who underwent ER for superficial ESCC at a tertiary cancer center between 2006 and 2017. The study endpoints were the incidence of metachronous HNCs after esophageal ER, risk factors for metachronous HNCs, and the association between detected metachronous HNCs and surveillance intervals. RESULTS: Among 644 patients, 137 metachronous HNC lesions were identified in 89 patients over a median follow-up of 63.0 months. The 10-year cumulative incidence of metachronous HNCs was 25.4%. Multivariate analysis identified male sex, esophageal grade C Lugol-voiding lesions, and metachronous ESCC within 1 year after ER as independent risk factors for metachronous HNCs. Surveillance intervals (≥ 7 months) were independently associated with the detection of larger HNCs (≥ 20 mm), but no statistically significant association was observed with the need for invasive treatment, including surgery, radiotherapy, or chemoradiotherapy. Tumor location in the postcricoid area or on the posterior wall of the hypopharynx was significantly associated with the need for invasive treatment. CONCLUSIONS: Metachronous HNCs frequently occur after esophageal ER, particularly in high-risk patients. Post-ER endoscopic surveillance should be performed not only to detect metachronous ESCCs but also to identify metachronous HNCs.