Proposal of a Classification System for Adenocarcinoma Involving the Ileocecal Valve (Bauhin's Valve): A Retrospective Study of 689 Right Hemicolectomized Patients.

BACKGROUND/AIM As of 2020, adenocarcinoma arising in the ileocecal valve (ICV-A) has been examined along with cecal and right colon cancer (RCC) under the collective heading "ileocecal" tumor. We propose a new classification system for this cancer. PATIENTS AND METHODS We retrospectively analyzed RCC patients from 2003 to 2019. The scheme was: i) Type I cancer for adenocarcinomas residing in ICV; ii) Type II, if they reside 1 to 5 mm from ICV; iii) Type III, 6 mm to 10 mm from ICV; iv) Type IV, at 1,1 to 5 cm; v) Type V, at more than 5 cm (ascending colon cancer). RESULTS Of 689 hemicolectomized patients, there were 91 (13.2%) Type I, 87 Type II (12.6%), 38 (5.5%) Type III, 157 (22.8%) Type IV and 314 (45.6%) Type V. Each type was associated with at least one clinicopathologic feature. CONCLUSION ICV-A was classified into five types (I-V) according to the distance from ICV. Further studies are needed in order to corroborate our findings.