Sphincter saving endoscopic resection of anorectal gist arising from the internal anal sphincter. No relevant disclosures. Anorectal gists are rare and they arise from the circular muscles of the rectum or the internal anal sphincter. Standard treatment is surgical. However, sphincter saving surgery is difficult when the lesion involves the internal anal sphincter, which may necessitate abdominal perineal resection with permanent colostomy. STR and EFTR can be implemented in the rectum to perform sphincter saving resection of suitable subepithelial lesions. Choice of technique depends on the morphology and location of the lesion. This video demonstrates two different techniques of sphincter preserving endoscopic resection of anorectal gist and discusses the choice of approach and technical details of these procedures. First case is a 57-year-old male, case of biopsy proven gist, was advised abdominal perineal resection with end colostomy which was refused by the patient, after which he was started on neoadjuvant imatinib. Sigmoidoscopy showed a non-ulcerated anal canal subepithelial lesion on retroflexion and rectal EOS showed the subepithelial lesion was arising from the muscular dyspropria. Anorectal manometry was normal. STR was planned for the patient. The procedure was performed with the patient in jackknife position under general anesthesia using CO2 insufflation. Submucosal tunneling endoscopic resection involves localizing the tumor, followed by submucosal injection, after which submucosal tunnel is created and enucleation of the tumor is performed and closure of the cavity. As the lesion was not clearly visible on forward viewscopy, simultaneous digital palpation was performed to ascertain the position of the lesion. The digital border of the lesion was marked to preserve the external anal sphincter. This was followed by submucosal injection and a submucosal cushion was created. A transverse mucosal incision was made in view of the close proximity of the lesion with the anal vag, after which a tunnel entrance was made and longitudinal submucosal tunneling was performed in the caudal to cranial direction. Submucosal dissection was continued to achieve adequate exposure of the lesion. The lesion was seen to extend along the axis of the anal canal. Encapsulated lesion was seen arising from the muscularis propria, which was dissected using dual j knife and IT nano knife, maintaining the intactness of the tumor capsule. Further dissection was continued to free the margins of the tumor. The characteristic twitching of the skeletal muscles while cautery is applied helps prevent inadvertent skeletal muscle injury. The lesion was found to involve the internal anal sphincter. The internal anal sphincter was dissected to free the tumor. The tumor was freed of its attachments and the specimen was retrieved. The tunnel and the cavity were reassessed and hemostasis was confirmed. The incision site was closed using endoclips. The postoperative period was uneventful and histopathology showed clear margins. Anorectal manometry on follow-up was normal. The second case was found to involve a hemostasis. Anorectal manometry on follow-up was normal. The second case was a similar lesion. However, in view of the surface ulceration, endoscopic full thickness resection was planned. The procedure was performed with the patient in jack-knife position. Endoscopic full thickness resection involves localization of the tumor, after which submucosal injection is given, followed by incision and complete excision of the subdipathylial lesion, which is followed by closure of the cavity using clips. The lesion with ulcerated overlying mucosa was found just proximal to the anal verge. The incision was taken after marking the borders of the lesion using coagulation current. Submucosal dissection was continued. Dense submucosal fibrosis was encountered during the dissection. The lesion was seen to involve the internal anal sphincter, which was dissected to free the margins of the tumor. The incision was taken at the cranial end with the scope in the retroflex position. The tumor was shaved off its attachments from the serocel layer. The characteristic twitching of the skeletal muscles while applying cautery helped prevent inadvertent injury to the skeletal muscles. Blunt dissection was carried out to free the tumor capsule from the levator ani. The attachments were dissected, maintaining the intactness of the tumor capsule, and the specimen was retrieved. The cavity was assessed after the resection, and the vessels at the base of the cavity were coagulated using coagulation forceps. Addictive subdipathylial lesion was found. Adequate closure of the proximal end of the defect was done using endosutures and clips. Partial closure of the distal end of the defect was done to help in free drainage of seroma and collections. The postoperative period was uneventful, with histopathology showing clear margins. There was complete healing of the incision, There was complete healing of the incision site on 8-week follow-up. Surgical intervention in anorectal jist is a radical approach which significantly affects the quality of life. Our approach was to achieve endoscopic excision with the aim to achieve clear margins, at the same time minimize morbidity by avoiding injury to the external anal sphincter. Choosing the appropriate resection technique for endoscopic resection is based on the morphological characteristics of the lesion. Presence of mucosal ulceration necessitates the need for full thickness resection, whereas STIR is an appropriate resection technique in those lesions with normal overlying mucosa. Simultaneous digital palpation, mucosal marking at the distal end of the lesion just inside the dentate line, and transverse mucosal incision were the technical modifications implemented for the first case. Blunt dissection of the tumor capsule from the levator ani and partial closure of the defect were the technical modifications implemented in the second case. These technical modifications helped prevent inadvertent injury to the external sphincter, thereby preserving continence. This video emphasizes the importance of optimal technique selection in such situations and the important technical aspects of both these procedures.

sphincter-preserving endoscopic resection

anorectal gist

neoadjuvant imatinib

submucosal tunneling endoscopic resection

endoscopic full thickness resection