Transanal single-port microsurgery for rectal tumors: minimal invasive surgery under spinal anesthesia

Background Transanal minimally invasive surgery (TAMIS) for rectal tumors has been introduced as an alternative approach to transanal endoscopic microsurgery (TEM). TEM has some limitations, such as the need for special equipment, expensive cost, and steep learning curve. In this study, we address the technical feasibility of TAMIS under spinal anesthesia and its short-term postoperative outcomes. Methods From July 2011 to September 2012, 25 consecutive patients with middle or upper third rectal masses underwent TAMIS. Tumors were located 6–17 cm from the anal verge. After spinal anesthesia, a single-incision laparoscopic surgery port was inserted into the anal canal. With this access, conventional laparoscopic instruments, including a grasper and monopolar electrocautery and suction device, were used to perform the transanal excision. A hook-type monopolar electrocautery or harmonic scalpel was used for dissection. The defect of the rectum was closed by interrupted sutures. Data concerning demographics, details of operative procedure, postoperative pain, and pathologic results were collected prospectively. To evaluate anal sphincter injury, an endoanal ultrasonography and fecal incontinence severity index survey were performed at 3–6 months after the operation. Results Of the 25 patients, nine had adenocarcinomas, nine had neuroendocrine tumors, three had tubular adenomas with high-grade dysplasia, three had tubular adenomas, one had a tubulovillous adenoma, and one had a gastrointestinal stromal tumor. The median distance from the tumor mass to the anal verge was 9.0 (range 6–17) cm. The median operative time was 45.0 (range 20–120) min. All patients received TAMIS without conversion to laparoscopic resection. There were no intraoperative complications or postoperative morbidity. The median postoperative hospital stay was 3.0 (range 2–7) days. No sphincter injury was detected by endoanal ultrasonography. Conclusions TAMIS under spinal anesthesia is a safe and feasible technique for resection of middle and upper rectal masses. Spinal anesthesia is adequate for this procedure.