Enhancing Surgical Efficiency and Cost-Effectiveness With TaTME-Combined Robot-Assisted Surgery for Lower Rectal Cancer

Background: Robot-assisted rectal surgery (RAS) offers improved dexterity and visualization; however, the high cost of equipment and consumables remains a major challenge for hospital management. At our institution, we have adopted a combined approach using transanal total mesorectal excision (TaTME) for lower rectal cancers, aiming to shorten operative time and enable two procedures per day to improve cost-efficiency. Methods: This retrospective cohort study included 112 patients who underwent RAS for rectal cancer between 2019 and 2024, excluding those requiring lateral lymph node dissection. Patients were divided into a robotic-only group (Ra/RS tumors, n = 75) and a TaTME-combined group (Rb tumors, n = 37). Surgical outcomes and institutional profitability per case were compared, including the number of cases performed twice daily. Results: Despite much lower tumor height from the anal verge (3 vs. 10 cm, p < 0.001), the TaTME-combined group showed significantly shorter operative time than the robotic-only group (235 vs. 317 min, p < 0.001). Two-case-per-day robotic operations were achieved in 73.0% of the TaTME-combined group (27 patients) compared to only 20% in the robotic-only group (15 patients). Oncological outcomes and complication rates were comparable between the groups. In the TaTME-combined group, performing two procedures per day resulted in a greater gross profit per case (JPY 321 800/case) compared to performing one conventional robotic LAR per day (JPY 224 300/case). Conclusions: TaTME-combined RAS for lower rectal cancer enables efficient surgical scheduling and improved cost-effectiveness while maintaining oncological safety. This strategy holds promise as a model for economically sustainable rectal cancer care.