Management of ureteral stricture disease after radiation therapy for pelvic malignancies. A retrospective, multi-Institutional analysis

Objectives: A radiation-induced ureteral stricture (RIUS) is a challenging condition in urologic surgery, and the optimal surgical strategy is still a matter of debate. The aim of this study was to report post-operative outcomes of minimally invasive management of this condition from a multi-institutional cohort. Methods: Data of patients with diagnoses of RIUS at five referral robotic centers between January 2017 and December 2022 were retrospectively analyzed. Pre-, intra- and post-operative variables were collected. Recurrence was defined as the presence of flank pain combined with imaging findings for obstruction, and requiring further management. Univariate and multivariate logistic regression models were built to identify predictors of ureteral stricture recurrence. Results: Fifty-three patients with a diagnosis of an RIUS were included. Primary pelvic malignancy was mostly cervical (42%). In 72% of cases (mostly mid-proximal and short strictures) endourological management was attempted, which was deemed successful in 74% of patients at stent removal. The endourology success rate at a median follow-up of 12 months was 59%. Twenty-five patients (47%) were scheduled for robotic surgery. The reconstructive techniques most often performed were end-to-end anastomosis (44%) and ureteral reimplantation (52%). Three low-grade Clavien-Dindo post-operative complications (12%) occurred. Robotic surgery was successful in all cases except one. Considering the entire cohort, eight patients (15%) developed recurrence at a median follow-up of 5 months. All patients with recurrence were managed by permanent drainage. A statistically significant improvement in eGFR with respect to baseline was found at a median follow-up of 12 months (p = 0.007). The univariate logistic regression model identified ureteral stricture length >2 cm (OR 6.4, 95% C.I. 1.1-36.9, p = 0.04) and concomitant chemotherapy (OR 8.9, 95% C.I. 1.6-49.9, p = 0.01) as predictors of recurrence. At multivariate analysis concomitant chemotherapy was confirmed as an independent predictor of recurrence (OR 7.8, 95% C.I. 1.3-49.0, p = 0.03). Conclusions: Endourological management of an RIUS is reasonable for short and mid-proximal ureteral strictures, while robotics is required in almost all the remaining cases. Up to 15% of recurrence develops within 6 months. Re-do reconstructive surgery is rarely performed, even in referral centers.