Robotic versus transanal total mesorectal excision in sexual, anorectal, and urinary function: a multicenter, prospective, observational study

PURPOSE: Improved long-term survival after low anterior resection (LAR) for rectal cancer highlights the importance of functional outcome. Urogenital and anorectal dysfunction is frequently reported after conventional LAR. Advanced minimally invasive techniques such as robotic (RoTME) and transanal total mesorectal excision (TaTME) might improve functional results by precisely dissecting and preserving autonomic nerves. We compared functional outcomes after RoTME or TaTME in a multicenter study.

METHODS: One hundred twenty patients (55 RoTME/65 TaTME) were prospectively included in four participating centers. Anorectal (Wexner and low anterior resection syndrome (LARS) Score), urinary (International Consultation on Incontinence-Male/Female Lower Urinary Tract Symptoms Score (ICIQ-MLUTS/ICIQ-FLUTS) and International Prostate Symptom Scale (IPSS)), and sexual (International Index of Erectile Function (IIEF), Female Sexual Function Index (FSFI)) outcomes at 12 months after surgery were compared to preoperative scores. The response rate to the 1-year postoperative functional assessment by questionnaire was 79.5%.

RESULTS: RoTME enabled better anorectal function compared to TaTME (LARS score 4.3 ± 2.2 vs. 9.8 ± 1.5, p = 0.038, respectively). TaTME proved superior at preserving male urinary function, while female urinary function was comparable in both groups, with only mild postoperative impairment (RoTME vs. TaTME, respectively: ICIQ-MLUTS 13.8 ± 4.9 vs. 1.8 ± 5.8, p = 0.038; ICIQ-FLUTS Incontinence Score - 0.3 ± 1.0 vs. - 0.2 ± 0.9, p = 0.844). Both techniques demonstrated comparable male (RoTME - 13.4 ± 2.7 vs. TaTME - 11.7 ± 3.4, p = 0.615) and female (RoTME 5.2 ± 4.6 vs. TaTME 10.5 ± 6.4, p = 0.254) sexual function.

CONCLUSION: After adjustment for risk factors, RoTME provided better anorectal functional results, whereas TaTME was better at preserving male urinary function. Overall, both techniques demonstrated only mild postoperative functional impairment.