Prospective study of urinary function and analysis of risk factors after rectal cancer surgery.

Background: Alterations in urinary function are complications of rectal cancer surgery. The aim of this study was to prospectively analyze the changes in urinary function in patients operated on for rectal cancer, and to identify risk factors that may have an impact on the deterioration of postoperative urinary function.

Methods: A prospective study of urinary function in rectal cancer patients who had elective oncological resection with curative intention at the Arnau de Vilanova Hospital in Valencia, Spain, from January 2017 to March 2019. The evaluation of urinary function was performed using the International Prostate Symptom Score (IPSS) preoperatively, at 6 and 12 months after surgery. Predictive factors of urinary dysfunction were identified by univariate and multivariate analysis.

Results: Ninety-four patients were enrolled in the study. Eighty-seven of them completed all the follow-up assessments (48 men and 39 women, mean age 65.74 ± 10.95 years,). The mean IPSS was 7.96 ± 7.59 preoperatively, 9.01 ± 6.81 at 6 months, and 8.63 ± 5.59 at 12 months, without statistically significant differences. There were no differences in IPSS between males and females. Preoperative urinary dysfunction was 39% and at 12 months, a deterioration occurred in 23 patients (26.4%). IPSS analysis of symptoms showed a statistically significant worsening of nocturia at 6 months (p = 0.002) and 1 year after surgery (p = 0.037) in women. American Society of Anesthesiologists (ASA) class (OR: 11, [95% CI2.4-53]; p = 0.010), surgical difficulty (OR: 4.5, [95% CI 1-19]; p = 0.027) and anastomotic leakage (OR: 14, [95% CI 1.6-117]; p = 0.010), were identified as independent risk factors for deterioration of urinary function after surgery.

Conclusions: Our study showed worsening urinary dysfunction after rectal cancer surgery in 26.4% of the patients. However, there were no statistically significant differences in mean IPSS scores at the three assessment times (preoperatively, 6 months, 12 months). ASA class, surgical difficulty, and anastomotic leakage may predict postoperative deterioration.