Columnar-lined esophagus measuring less than 1 cm as a risk factor for esophageal squamous cell carcinoma in Japanese men

Background and aims Several case series have noted an association between Barrett’s esophagus (BE) and esophageal squamous cell carcinoma (ESCC). We conducted a nationwide retrospective cohort study to examine the association between baseline BE status, particularly ultra-short-segment BE (USSBE; BE <1 cm), and subsequent ESCC development, focusing on the presence or absence of extensive gastric atrophy (GA). Methods Consecutive male participants who underwent endoscopy at 17 health check-up institutes in Japan between 2013 and 2017 and had follow-up endoscopy by December 2022 were enrolled. Baseline endoscopic images were reviewed to assess GA and BE status. The primary outcome was ESCC development during follow-up. The association between BE status and ESCC was estimated using the Kaplan–Meier method and Cox regression. Results Among 20,402 male subjects, 7161 (35.1%) had USSBE. During 116,483.1 person-years of follow-up, 73 cases of ESCC developed. The incidence of ESCC was highest among individuals with USSBE (0.0946%/year). Multivariable analysis revealed that USSBE was independently associated with ESCC (adjusted hazard ratio [HR] 1.82, 95% confidence interval [CI] 1.03–3.24). In exploratory subgroup analyses, USSBE was independently associated with ESCC (adjusted HR 2.40, 95% CI 1.13–5.13) among individuals with extensive GA, while no significant association was observed among those without (adjusted HR 1.34, 95% CI 0.64–2.81; p for interaction = 0.369). Conclusions This is the first study to demonstrate a significant association between USSBE and ESCC. USSBE may help identify individuals at increased risk of ESCC. Exploratory subgroup findings according to GA status require further validation.