Endoscopic submucosal dissection in management of colorectal tumors near or involving a diverticulum: a retrospective case series.

Surgery is the standard treatment for colon tumors associated with diverticulum. se of endoscopic submucosal dissection (ESD) to treat such tumors is controversial. The aim of this study was to assess the safety and feasibility of ESD in treating superficial colorectal tumors situated near or involving diverticulum. Consecutive patients from two referral centers who had colorectal tumors near or involving diverticulum treated by ESD were retrospectively studied. Clinicopathological characteristics and clinical outcomes were analyzed. Of the 12 patients studied, six had tumors near diverticulum and six had tumors involving diverticulum. The overall en-bloc R0 resection rate, median tumor size and procedure time were 67 %, 26.5 mm (range, 15 - 80 mm) and 110 minutes (range, 50 - 220 minutes), respectively. For tumors near diverticulum group, the en-bloc R0 resection rate was 100 % and no adverse events (AEs) or residual/recurrent tumors were observed. In contrast, for intradiverticular tumors group, the en-bloc R0 resection rate was low at 33 %, and one AE (perforation) was observed. The diverticula were ≥ 6 mm in diameter in the patients with incomplete resection. However, all but one diverticulum was unrecognized before ESD. Two residual tumors were detected at the 12-month surveillance and one required surgery. This case series indicates that ESD is safe and feasible for treating colorectal tumors near a diverticulum and might be feasible for tumors involving a diverticulum smaller than 6 mm. Selection for smaller diverticulum size may contribute to higher en-bloc R0 resection rates.