Tanya Castelino, MD1, Nancy Morin, MD, FRCSC, FACS2, Carol-Ann Vasilevsky, MD, FRCSC, FACS2, Julio Faria, MD, FRCSC2, Gabriela Ghitulescu, MD, FRCSC2, Philip Gordon, MD, FRCSC, FACS2, Marylise Boutros, MD, FRCSC2. 1McGill University, 2Division of Colon & Rectal Surgery, Jewish General Hospital
Objective: Transanal endoscopic surgery (TES) has several unique advantages for the resection of large benign polyps and carcinomas of the rectum, however there are several barriers to its widespread use, including a steep learning curve, technical challenges and specialized equipment. The purpose of this video is to demonstrate the technique, as well as tips and tricks that we have developed through our experience with TES.
Pre-operative planning: The standard indications for TES include excision of benign polyps that are not endoscopically resectable and early T1N0 rectal carcinomas. Prior to surgery, it is important to evaluate the patient with rigid proctoscopy in order to clearly document the location of the lesion. This step is crucial for successful intra-operative positioning.
Positioning: When using the rigid proctoscope platform, we routinely position the lesion at 6 o’clock. Lesions of the lateral aspect of the rectum require lateral decubitus positioning, while posterior lesions are removed in lithotomy and anterior lesions are removed in the prone position.
Excision of the lesion: The first step is to score a circumferential resection margin 1 cm from the tumour. Electrosurgery is then used to excise a full-thickness specimen. In cases where we intend curative resection for possible early cancer, we choose a full-thickness approach. For very select large lesions that are likely benign, we perform a submucosal resection.
Closure of the defect: The first step to close the defect is bisecting the wound. The defect is then closed using a self-locking, barbed, absorbable suture, in a running fashion and with full-thickness bites. Our practice is to close every defect, although some argue that it is not necessary to close distal extraperitoneal defects. The benefits of closing the defect are primarily to obtain hemostasis and to prevent post-operative pain. Lastly, closure of defects can be challenging, therefore we feel that routine closure of the defect will allow surgeons to feel comfortable with intra-rectal suturing in the event that an intraperitoneal defect is made.
Post-operative evaluation: We view TES as an excisional biopsy. If there is an invasive carcinoma with poor prognostic features including Sm3 involvement, perineural involvement, lymphovascular invasion, tumour budding, mucin, and poor cell differentiation, we recommend further radical, curative surgery.