Comparative study of robot-assisted surgery for right-sided colon cancer: a propensity score-matched analysis of the hinotori Surgical Robot System and the da Vinci Surgical Robot System

Purpose: The da Vinci Surgical System has led to major advances in robot-assisted colorectal surgery. Following its patent expiration, domestic alternatives such as the hinotori Surgical Robot System have been developed in Japan. However, clinical comparisons between the hinotori and the da Vinci Xi systems remain limited. This study aimed to compare the short-term outcomes of right-sided colon cancer surgeries performed with either system using propensity score matching. Methods: This retrospective study included 39 patients who underwent da Vinci-assisted surgery and 37 who underwent surgery using the hinotori system. Propensity score matching was performed using 7 covariates: age, sex, body mass index, American Society of Anesthesiologists physical status, clinical T and N categories, and surgeon experience (≥100 prior robotic colorectal surgeries). To assess the robustness of the findings, inverse probability weighting was also applied using the same covariates. Surgical, postoperative, and pathological outcomes were evaluated. Results: After matching, 27 patients were included in each group. The hinotori group had significantly longer operative and console times (236 minutes vs. 191 minutes, P = 0.001; 140 minutes vs. 90 minutes, P < 0.001). No significant differences were observed in blood loss, complication rates, length of hospital stay, or lymph node harvest. No conversions or reoperations occurred. One readmission for ileus was noted in the da Vinci group, whereas none occurred in the hinotori group. Conclusion: Right colectomy assisted by the hinotori system demonstrated short-term outcomes equivalent to those of the da Vinci system, despite a prolonged operative time. Further prospective studies with larger sample sizes and longer follow-up are warranted.