Experimental Assessment of Endoscopic Mucosectomy with a Cap-Fitted Panendoscope

Abstract

Background and Study Aims: The use of a cap-fitted panendoscope is one method of carrying out endoscopic mucosectomy in the esophagus, stomach, and large intestine. The purpose of this study was to determine the optimal volume of physiological saline for submucosal injection, the rate of mucosal extension after saline injection, the initial size of the resected mucosal specimen, and the most appropriate heights for the fitted caps used in the colon and in the rectum, respectively.

Methods: Endoscopic mucosectomies using cap-fitted panendoscopes were carried out on resected surgical specimens from ten patients with colorectal cancer.

Results: It was necessary to inject 12 ml of saline under the mucosa to prevent perforation. Submucosal saline injection extended the mucosa by 1.4 ± 0.2 times. A cap with a height of 7 mm is suitable for performing mucosectomy in the colon safely, while both 7 mm and 10 mm caps can be used in the rectum. The initial size of the resected mucosal specimens obtained with both caps was 12-20 mm (mean 14 mm) in diameter, with no significant differences. As the sizes of resected mucosal specimens reported in the past have been obtained after submucosal saline injection, it appears that larger specimens can be resected with the cap-fitted panendoscope than with conventional methods.

Conclusions: The conditions under which endoscopic mucosectomy using the cap-fitted panendoscope can be performed safely in the colon and the rectum were suggested by this experimental study using resected specimens. A saline injection of 12 ml under the mucosa is necessary to prevent perforation. A cap with a height of 7 mm is the most suitable size for the colon, while both 7 mm and 10 mm caps can be used in the rectum.