Objectives: To evaluate the risk of acute urinary retention (AUR) and sequelae after urethra-sparing magnetic resonance imaging (MRI)-guided prostate brachytherapy.
Methods: Between 1997 and 2003, MRI-guided prostate brachytherapy was performed after external beam radiotherapy (n = 60) or as monotherapy (n = 188) following a diagnosis of low-risk prostate adenocarcinoma. The median prostate gland volume was 40 cm3 (range 16 to 184). Of the 248 patients, 88 (35%) had prostate gland volumes greater than 45 cm3. The median follow-up was 40 months.
Results: Of the 248 patients, 18 (7%) developed AUR. Of the 248 patients, 2% (3 of 160), 6% (3 of 49), 28% (8 of 29), and 40% (4 of 10) of patients experienced AUR if the prostate gland volume was less than 45, 45 to 60, 60 to 90, or greater than 90 cm(3), respectively (P <0.0001). Retention requiring intermittent self-catheterization resolved in one half of the patients by 2 weeks and had resolved in all patients by 6 weeks. At 1, 3, and 6 months after implantation, 100%, 57%, and 29% of patients who experienced AUR, respectively, used Flomax (P <0.0001). The mean Flomax dose used decreased from 0.9 mg at 1 month to 0.53 mg at 1 year.
Conclusions: AUR after urethral-sparing MRI-guided prostate brachytherapy is volume dependent and is self-limited despite very large prostate gland volumes.