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

Abstract

Background and study aims Surgery is the standard treatment for colon tumors associated with diverticulum. U 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. Patients and methods 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. Results 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. Conclusions 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.

Fig. 1

Classification of tumors related to the diverticular orifice. a Near type: the tumor reached the diverticular border, but did not enter the diverticular orifice. b Involving type: the tumor reached and entered the diverticular orifice; when the lesion fully covered the diverticulum, the diverticulum was unrecognized before ESD was performed.

Fig. 2 a

A 20-mm LST-NG tumor was detected in the cecum. b Characterized as tumor type V _I Kudoʼs pit pattern, the tumor was resected initially by ESD. c During the ESD procedure, it was observed that the tumor was involving completely a diverticulum. d Hybrid ESD with strip biopsy was necessary. e Finally, the lesion was resected in piecemeal. f Resected specimen (mucosal side). g Resected specimen (submucosal side). ESD, endoscopic submucosal dissection; LST-NG, laterally spreading tumor-non-granular.

Fig. 3 a

An 80-mm LST-mixed tumor, Sano type 2, was detected in the sigmoid colon. b Characterized as tumor type IV Kudo's pit pattern with serrated features, the tumor was resected by ESD. c,d During the procedure, it was observed that the lesion was involving a diverticulum (black arrow), and in addition, a pin-hole perforation was detected (white arrow). e A traction technique was used with a clip and silk line. f Finally, the lesion was resected en-bloc. ESD, endoscopic submucosal dissection; LST, laterally spreading tumor.