Objective To investigate the application value of Da Vinci robotic transanal minimally invasive surgery (R‑TAMIS) for local resection of rectal neoplasms.

Methods The retros-pective and descriptive study was conducted. The clinicopathological data of 7 rectal neoplasms patients undergoing R‑TAMIS in Daping Hospital of Army Medical University from June 2017 to March 2021 were collected. There were 3 males and 4 females, aged (60±7)years. Observation indicators: (1) intraoperative situations; (2) postoperative recovery; (3) postoperative histopatholo-gical examinations; (4) follow‑up. Follow‑up was conducted using telephone interview or outpatient examination to detect readmission of patients within postoperative 30 days, tumor recurrence and metastasis and survival of patients. Follow‑up was performed at postoperative 1, 3, 6 months and once every 6 months thereafter up to April 2021. Measurement data with normal distribution were represented as Mean±SD, and measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers.

Results (1) Intraoperative situations. All the 7 patients underwent R‑TAMIS successfully without conversion to laparotomy or laparoscopic surgery. Of the 7 patients, 2 cases underwent full‑thickness rectal resection and 5 cases underwent submucosal dissection of tumor. The rectal wounds were not sutured in 2 cases because of large lesions, and the rectal wounds were sutured with synthetic sutures in 5 cases after resection of lesions. Transanal drainage tube was placed in 2 cases and not in 5 cases. The volume of intra-operative blood loss of the 7 patients was 15(range, 2‒50)mL. The total operation time of the 7 patients was (91.4±18.4)minutes, including (19.1±2.3)minutes for transanal platform placement and Da Vinci robotic surgical system installation, and (72.3±16.6)minutes for operation. There was no intraoperative complication such as urethral injury. (2) Postoperative recovery. All the 7 patients started water drinking and out‑of‑bed activities at postoperative day 1 and liquid food intake at postoperative day 2. The time to postoperative first flatus of the 7 patients was 1(range, 1‒3)days. The two cases with transanal drainage underwent removing of transanal drainage at postoperative day 2. There was no postoperative complication and the duration of postoperative hospital stay of the 7 patients was 3(range, 3‒9)days. (3) Postoperative histopathological examinations. Of the 7 patients, 3 cases had villous adenoma, 2 cases had villous adenoma combined with high grade intraepithelial neoplasia, local canceration and tumor invasion into submucosa (stage SM1), 1 case had villous adenoma combined with high grade intraepithelial neoplasia, local canceration and tumor localized in the inner mucosa (stage Tis) and 1 case had moderately differentiated adeno-carcinoma with tumor invasion into superficial muscle layer (stage T2). All the 7 patients had negative surgical margins with none of tumor cell remained in the base. (4) Follow‑up. All the 7 patients were followed up for 18(range, 1‒42)months. One of the 7 patients showed rectal adenocarcinoma with tumor invasion into superficial muscle layer by the postoperative histopathological examina-tion and was recommended for remedial radical surgery. The patient refused further surgery and underwent 3 courses of oral capecitabine chemotherapy. The other 6 patients did not receive postoperative chemotherapy. None of 7 patients underwent readmission within postoperative 30 days, and no patient had tumor local recurrence, distant metastasis or death during the follow-up.

Conclusion R‑TAMIS for local resection of rectal neoplasms is safe and feasible for patients with rectal adenoma and early rectal cancer, with reliable short‑term efficacy and short‑term oncological efficacy.