One of the major problems of rectal cancer surgery is pelvic autonomic nerve damage, which is the main cause of urogenital dysfunction influencing postoperative quality of life. Costs for diagnostics and treatment of short and long-term urogenital dysfunction are immense. Varying degrees of urogenital dysfunction are found in up to 32% and 55% of patients with rectal cancer despite potentially nerve-sparing total mesorectal excision (TME).

The study will examine the impact of a newly developed continuous monitoring device for preservation of urogenital function in patients with TME for rectal cancer. 188 patients will be included in the prospective, randomized, single-blind, parallel group multi-centre trial including two arms (TME with and without intraoperative continuous monitoring of pelvic autonomic nerves). The primary efficacy endpoint is the change in urinary function measured by International Prostate Function Score (IPSS) 12 months after surgery. Genital functions measured as secondary endpoints. The application of the continuous intraoperative neuromonitoring device could enhance the objective intraoperative confirmation of pelvic nerve sparing surgery. The investigators hypothesis is that the use of his device minimizes the risk of postoperative urogenital dysfunction in patients with TME for rectal cancer. An enormous reduction of treatment costs is to be expected.

Inclusion Criteria:

• informed consent
• histologically confirmed carcinoma of the rectum (≤ 16 cm from anal verge)
• fit for radical surgery
• total mesorectal excision
• age 18-80 years

Exclusion Criteria:

• history of operation of the urinary tract (e.g. prostatectomy)
• pacemaker
• emergency operation
• multivisceral resection in the pelvis
• partial mesorectal excision
• eligibility for local excision (TEM, intestinal wall resection)
• ongoing infection or sepsis
• severe untreated physical or mental impairment
• pregnancy or breastfeeding
• women of childbearing potential who are not using a highly effective birth control method
• missing preoperative data on urogenital or anorectal function
• simultaneous participation in another clinical trial
• previous participation in this clinical trial
• lack of cooperation with the trial procedure