Robotic natural orifice specimen extraction surgery versus robotic transabdominal specimen extraction surgery for early-stage rectal cancer: a multicenter propensity score-matched analysis (in China).

Background: Despite the global increase in the adoption of robotic natural orifice specimen extraction surgery (R-NOSES), its advantages over robotic transabdominal specimen extraction surgery (R-TSES) for treating early-stage rectal cancer remain debated. There is scant nationwide, multicenter studies comparing the surgical quality and short-term outcomes between R-NOSES and R-TSES for this condition.

Objective: This retrospective cohort study was conducted nationally across multiple centers to compare the surgical quality and short-term outcomes between R-NOSES and R-TSES in early-stage rectal cancer.

Design: Multicenter retrospective cohort trial.

Setting: Eight experienced surgeons from 8 high-volume Chinese colorectal cancer treatment centers.

Patients: The study included 1086 patients who underwent R-NOSES or R-TSES from October 2015 to November 2023 at the 8 centers. Inclusion criteria were: (1) histologically confirmed rectal adenocarcinoma; (2) robotic total mesorectal excision; (3) postoperative pathological staging of TisN0M0 or T1-2N0M0; (4) availability of complete surgical and postoperative follow-up data. Patients were matched 1:1 in the R-NOSES and R-TSES groups using the propensity score matching (PSM) technique.

Results: After PSM, 318 matched pairs with well-balanced patient characteristics were identified. The operation time for the R-NOSES group was significantly longer than that for the R-TSES group [140 min (125-170 min) vs. 140 min (120-160 min), P = 0.032]. Conversely, the times to first flatus and initial oral intake in the R-NOSES group were significantly shorter than those in the R-TSES group [48 h (41-56 h) vs. 48 h (44-62 h), P = 0.049 and 77 h (72-94 h) vs. 82 h (72-96 h), P = 0.008], respectively. Additionally, the length of postoperative hospital stay was shorter in the R-NOSES group compared with the R-TSES group [7 day (7-9 day) vs. 8 day (7-9 day), P = 0.005]. The overall postoperative complication rates were similar between the groups (10.7% in the R-NOSES group vs. 11.9% in the R-TSES group, P = 0.617). However, the R-NOSES group had a lower incidence of wound complications compared to the R-TSES group (0.0% vs. 2.2%, P = 0.015). Regarding surgical stress response, the R-NOSES group showed superior outcomes. Additionally, patients in the R-NOSES group required fewer additional analgesics on postoperative days 1, 3, and 5 and reported lower pain scores compared to the R-TSES group. The body image scale (BIS) and cosmetic scale (CS) scores were also significantly higher in the R-NOSES group. Furthermore, the R-NOSES group demonstrated significantly better outcomes in functional dimensions such as physical, role, emotional, social, and cognitive functioning, and in symptoms like fatigue and pain, when compared to the R-TSES group.

Limitations: It is imperative to ensure the safe and standardized implementation of R-NOSES through the establishment of a uniform training protocol.

Conclusions: These results affirm that R-NOSES is a safe and effective treatment for early-stage rectal cancer when meticulously executed by skilled surgeons.