Efficacy and safety of transrectal natural orifice specimen extraction compared with conventional laparoscopy surgery for selected patients with colorectal cancer: a propensity score matching analysis and literature review

Purpose: Conventional laparoscopy (CL) surgery requires mini-laparotomy to extract the pathological specimen. However, by using a natural orifice as the delivery route, natural orifice specimen extraction (NOSE) surgery avoids a large incision. This study analyzed the safety and efficacy of NOSE compared with CL surgery for colorectal cancer. Methods We conducted a retrospective analysis of 1,189 patients who underwent surgery for primary colorectal cancer between the cecum and upper rectum. Propensity score analyses were applied to the NOSE and CL groups in a 1:1 matched cohort. Results Compared with the CL group, the NOSE group experienced a shorter time to first flatus (1.6 ± 0.8 vs. 2.0 ± 1.2 days, p < 0.001), first stool (2.7 ± 1.5 vs. 4.1 ± 1.9, p < 0.001), liquid diet (2.3 ± 1.3 vs. 3.6 ± 1.8 days, p < 0.001), soft diet (3.9 ± 2.0 vs. 5.2 ± 1.9 days, p < 0.001) and a shorter hospital stay (5.1 ± 3.5 vs. 7.4 ± 4.8 days, p < 0.001). The NOSE group exhibited lower mean pain intensity and lower highest pain intensity on postoperative days 1, 2, and 3. Conclusion NOSE resulted in reduced time to oral intake, less postoperative pain, and a shorter hospital stay. We proposed a transrectal NOSE technique for right-sided colon cancer and left-sided colon cancer near the splenic flexure with comparable short-term outcomes. With this approach, we hope to expand the application of NOSE to colon cancer surgery irrespective of tumor location or patient sex.