Urinary incontinence (UI) remains an important complication after robot-assisted radical prostatectomy (RARP). While sarcopenia-related markers may help predict persistent UI, existing evidence is inconsistent and often based on subjective assessments. We aimed to evaluate the predictive value of preoperative psoas major muscle cross-sectional area (PMM-CSA) for moderate-to-severe UI 12 months after RARP and its association with longitudinal continence recovery.
This cohort study included 449 patients with prostate cancer who underwent RARP. PMM-CSA was measured on preoperative CT scans at the L3 vertebral level. UI volume, measured using a standardized 1-hour pad test (1hPT) at baseline and at 1, 3, 6, 9, and 12 months postoperatively, was classified as moderate-to-severe if it was ≥11 g. Univariable and multivariable logistic regression evaluated preoperative PMM-CSA as a predictor of moderate-to-severe UI at 12 months post-RARP. A multivariable-adjusted generalized estimating equation was used to assess the association between PMM-CSA and longitudinal changes in UI volume.
Moderate-to-severe UI was observed in 64 patients (14.3%) 12 months postoperatively and was significantly predicted by PMM-CSA (odds ratio per 1 cm2 increase: 0.86 [95% confidence interval: 0.79-0.92]). Postoperatively, UI volume peaked at 1 month, declined until 9 months, and then plateaued. Reduced PMM-CSA was associated with increased UI volume from 3 to 12 months postoperatively.
Preoperative PMM-CSA is a significant predictor of moderate-to-severe UI 12 months after RARP and is associated with the longitudinal continence recovery. Preoperative PMM-CSA evaluation may aid in risk stratification, tailored counseling, and preventive strategies.
Clinical genitourinary cancer. 2026 Apr 21 [Epub ahead of print]
Akihisa Hasegawa, Kenji Omae, Yuki Harigane, Kei Yaginuma, Hitomi Imai, Satoru Meguro, Kanako Matsuoka, Seiji Hoshi, Junya Hata, Yuichi Sato, Hidenori Akaihata, Soichiro Ogawa, Noriaki Kurita, Yoshiyuki Kojima
Department of Urology, Fukushima Medical University School of Medicine, Fukushima, Japan., Department of Innovative Research and Education for Clinicians and Trainees (DiRECT), Fukushima Medical University Hospital, Fukushima, Japan. Electronic address: ., Department of Innovative Research and Education for Clinicians and Trainees (DiRECT), Fukushima Medical University Hospital, Fukushima, Japan; Department of Clinical Epidemiology, Graduate School of Medicine, Fukushima Medical University, Fukushima, Japan; School of Medicine, Division of Rheumatology, Department of Medicine, Showa Medical University, Tokyo, Japan.