Identification of Risk Factors in Postoperative Urinary Dysfunction for Rectal Gastrointestinal Stromal Tumors.

Aim: Curative resection and organ preservation are important to manage rectal gastrointestinal stromal tumors; however, postoperative quality of life, including urinary function, remains a concern. Our prior findings suggest a high incidence of urinary dysfunction after surgical resection of rectal gastrointestinal stromal tumors. This study aimed to identify the incidence of risk factors for postoperative urinary dysfunction during surgery for rectal gastrointestinal stromal tumors. Methods: This retrospective study, conducted at our institution, included 45 patients who underwent surgery for rectal gastrointestinal stromal tumors between January 2008 and March 2022. Tumor size was assessed as the largest diameter via magnetic resonance imaging. Postoperative urinary dysfunction was defined as requiring urethral or intermittent catheterization at discharge. Results: Median tumor size was 50.0 mm (range, 10.0-110.0 mm). Of all 45 patients, 25 (53.3%) underwent complete autonomic preservation and 11 (24.4%) experienced urinary dysfunction at discharge. Univariable analysis identified tumor size ≥ 50.0 mm immediately before surgery (p = 0.04) and preoperative targeted therapy (p = 0.03) as risk factors. Multivariable analysis showed male sex (odds ratio = 8.2, 95% confidence interval: 1.32-50.60; p = 0.02) and tumor size ≥ 50.0 mm immediately before surgery (odds ratio = 9.0, 95% confidence interval: 1.46-55.20; p = 0.02) as independent preoperative risk factors. Conclusions: The incidence of postoperative urinary dysfunction after surgery for rectal gastrointestinal stromal tumors was 24.4%. The preoperative risk factors of postoperative urinary dysfunction were male sex (55.6%) and tumor size ≥ 50.0 mm immediately before surgery (53.3%).