Clinical patterns and pathogenesis of bladder leiomyoma: a multicenter observational study

To describe the clinical and tumor characteristics of bladder leiomyoma (BL) and to explore potential etiological factors and prognostic factors to guide management strategies.

Patients with histologically confirmed BL treated at 14 hospitals between 1995 and 2025 were included. Associations between tumor characteristics, symptoms, management, and outcomes were evaluated using appropriate statistical tests and logistic regression. A p-value < 0.05 was considered significant.

Among 74 patients (55.4% female, median age 60 years [IQR, 42.25-70.00]), 48.6% were asymptomatic at diagnosis, and 66.2% presented with at least one metabolic syndrome criterion. Tumors had a median size of 21.0 mm [IQR 13.50-35.00] and were most frequently endovesical (48.6%), followed by intramural (35.1%) and extravesical (16.2%) patterns; tumor size and location were not associated with preoperative symptoms but significantly influenced surgical management (p = 0.002). Transurethral bladder resection was the most common treatment (62.2%), followed by partial cystectomy (23.0%) and bladder excision (9.5%), with 68.8% of them performed laparoscopically. Early postoperative complications occurred in 8.1% of patients. Over a median follow-up of 14.3 months [IQR 2.3-48.0], recurrence occurred in 5.4% and persistent or worsening symptoms in 17.6% of patients. Initial LUTS were predictive of both recurrence and persistent postoperative symptoms (OR = 2.02 [1.20-4.61] and 2.38 [1.53-4.55], respectively).

This study represents the largest cohort of BL to date. The high proportion of asymptomatic cases suggests that its true incidence is underestimated. While recurrence was uncommon, persistent LUTS remained a concern among initially symptomatic patients, supporting a personalized, conservative therapeutic approach whenever feasible. Further studies are needed to clarify the biological mechanisms underlying BL and to optimize its management.