Impact of neoadjuvant treatment on functional outcomes after transanal total mesorectal excision (taTME)—a case series

Background: Total mesorectal excision (TME) is known to adversely impact functional outcomes. In a recent Phase II multicenter prospective trial, significant decline in defecatory and sexual function and fecal incontinence-related quality of life (FIQL) was documented following transanal TME (taTME) for rectal cancer, with neoadjuvant treatment (NAT) identified as a predictor of worse function. However, the impact of NAT on baseline function is poorly understood. Methods: Patients in a Phase II multicenter trial (NCT03144765) who underwent taTME with or without NAT completed validated functional questionnaires assessing fecal incontinence (FIQL, Wexner), defecatory function (COREFO), urinary function (IPSS), and sexual function (male: IIEF, female: FSFI). Data were collected pre-NAT, post-NAT, 3–4 months after ileostomy closure (FQ1), and 12–18 months post-taTME (FQ2). Paired t-tests or Wilcoxon tests compared scores between timepoints. Results: Of 71 patients who received NAT, 10 completed both pre- and post-NAT surveys. Median age was 58 years [IQR 48–61], and 7 patients were male. Tumors were located a median 4.75 cm [IQR 4.0–6.0 cm] from the anal verge. Median baseline COREFO score was 38.1 [29.2–49.8], indicating baseline defecatory dysfunction. No significant differences were observed between pre- and post-NAT scores, though FIQL scores demonstrated a trend toward worse incontinence-related quality of life post-NAT (p = 0.06). Postoperatively, Wexner, FIQL, and COREFO worsened from baseline and post-NAT levels, with partial improvement at 18 months post-op, without returning to baseline. No differences were observed in IPSS scores. IIEF scores showed no new erectile dysfunction post-NAT, but low sample size precluded FSFI analysis. Conclusion: Defecatory, urinary, and sexual function were not significantly altered by NAT, though FIQL trends suggest worsening incontinence-related quality of life. Assessment of function and health-related quality of life at baseline and after each phase of therapy may help better inform patients about the impact of multimodal rectal cancer treatment.