Abstract
BACKGROUND AND AIM: In terms of their longitudinal positioning, esophageal squamous cell carcinoma (ESCC) commonly arises in the middle segment of the esophagus. However, limited attention has been given to the circumferential aspect. This study aimed to investigate the prevalence and characteristics of ESCC lesions resected via endoscopic submucosal dissection (ESD), taking into consideration both longitudinal and circumferential positions. METHODS: We retrospectively evaluated 193 ESD-resected ESCC lesions and compared the occurrence rate of ESCC development and the degree of histopathological invasion across various circumferential and longitudinal positions. We scrutinized lesion characteristics by location, with a particular focus on the proportion of early-stage small lesions in each site. RESULTS: Regarding lesion location, 27 were situated on the anterior wall, 62 on the left, 66 on the posterior, and 38 on the right. Among the four circumferential positions, the anterior wall group had the smallest median tumor size. Additionally, the anterior wall group had the highest proportions of lesions with invasion depths limited to the epithelial layer and sizes < 10 mm, at 44.4% and 25.9%, respectively. Furthermore, a significant difference was noted among the four circumferential positions with respect to the proportion of ESCC lesions satisfying both criteria, with the highest proportion observed in the anterior wall group (p = 0.049). CONCLUSIONS: Our findings suggest that while ESCC occurrence on the anterior wall is less frequent, these lesions may present as small lesions with superficial invasion depths.