Predictors of Rectourethral Fistula Formation after Primary Whole-Gland Cryoablation for Prostate Cancer: Results from the Cryo On-Line Database Registry

Purpose: To define the incidence and risk factors associated with rectourethral fistula (RUF) formation following primary whole-gland cryosurgery using a multicenter centralized registry. Patients and Methods: The Cryo On-Line Data (COLD) registry was queried for men undergoing primary whole-gland cryotherapy between 1990 and 2014 who developed a RUF. Patient factors and disease parameters were correlated with RUF using chi-square and the t-test. Variables with p < 0.25 were entered into a binary logistic regression with stepwise backward elimination to determine the factors associated with RUF formation. Results: A total of 4102 men underwent primary whole-gland cryotherapy in the COLD registry at the time of analysis. Postoperative RUF was documented in 50 out of 4102 cases (1.2%). Patients with RUF had similar demographic data, prostate volume, preoperative prostate-specific antigen level, and clinical stage in comparison to those without fistula. On both univariate and multivariate analyses, postoperative urinary retention (odds ratio [OR]: 6.30; confidence interval [95% CI] 3.43-11.58, p < 0.001), preoperative Gleason score of ≥7 (OR: 1.92; 95% CI 1.08-3.43, p = 0.027), and preoperative incontinence (OR: 2.95; 95% CI 1.12-7.76, p = 0.028) were the most significant risk factors associated with RUF formation. Conclusion: Primary whole-gland cryotherapy for prostate cancer is associated with a historically low rate (1.2%) of postoperative RUF formation. The rate decreased further to 0.55% over the last several years, suggesting better patient selection and technical improvement. Postoperative urinary retention, Gleason score ≥7, and preoperative urinary incontinence were the key demographic, clinical, and pathologic features associated with RUF formation in this study.