Twenty patients undergoing taTME for rectal cancer is included. Following the closure of the rectal lumen by a purse string suture, rectal washout is performed with a total of 500 ml sterile water. Fluid samples are collected after every 100 ml by instilling 50 ml of saline after each washout. A sixth sample is collected from the presacral cavity. Each sample is cytologically examined by a pathologist and labelled either malignant or non-malignant.
The study aims to assess the existence of intraluminal malignant cells and the appropriate fluid volume needed to perform rectal washout during transanal total mesorectal excision (taTME) for rectal cancer.