Short-term outcomes of Transrectal Natural Orifice Specimen extraction compared with conventional minimally invasive surgery for selected patients with colorectal cancer: a propensity score matching analysis and literature review.

Purpose: Conventional minimally invasive 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 the need for a large incision. This study analyzed the short-term outcome of NOSE compared with conventional mini-laparotomy (CL) for colorectal cancer surgery.

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: After propensity score matching, each group included 201 patients. The NOSE group and CL group did not differ significantly in terms of baseline characteristics. Postoperative morbidity and mortality rates were comparable. 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 has several advantages over conventional mini-laparotomy following minimally invasive surgery for colon cancer. These advantages include reduced time to oral intake, shorter hospital stays, and less postoperative pain. NOSE can be adopted and applied to highly selective patients without additional risk of short-term complications.