Neuroendocrine Carcinoma of the Urinary Bladder: A Large, Retrospective Study From the French Genito-Urinary Tumor Group

Neuroendocrine carcinoma of the urinary bladder (NCUB) is rare, accounting for < 1% of bladder cancer cases, with scarce reported data available.We retrospectively reviewed the data from patients with NCUB treated at French institutions. The objectives were to describe the patient characteristics, treatments received, and outcomes (ie, disease-free survival [DFS], progression-free survival, overall survival [OS]) and investigate the prognostic factors.From 1997 to 2017, we included 236 patients, 173 with early-stage NCUB and 63 with advanced-stage NCUB. For those with early-stage disease, the median DFS was better for the patients who had received cisplatin-based chemotherapy compared with carboplatin (hazard ratio [HR], 1.95; 95% confidence interval [CI], 1.1-3.46), with no difference found between the neoadjuvant and adjuvant settings (HR, 1.1; 95% CI, 0.61-1.97). The median OS was 36 months (95% CI, 29-43 months) for stage I and II, 26 months (95% CI, 18 months to not reached) for stage IIIA, 16 months (95% CI, 12-21 months) for stage IIIB. The HR for stage IIIB compared with stage I/II was 2.6 (95% CI, 1.5-4.4). The DFS at 6 months was associated with OS (HR, 7.8; 95% CI, 4.1-15.0). For patients with metastases at diagnosis who had received chemotherapy, the median progression-free survival was 9 months (95% CI, 8-11) for first-line cisplatin and 6 months (95% CI, 4-13 months) for carboplatin; the median OS was 13 months (95% CI, 9-15 months). A high-risk Bajorin score (HR, 11.5; 95% CI, 1.2-112.6) and the use of carboplatin (HR, 2.26; 95% CI, 1.03-4.96) were associated with worse outcomes.In early-stage disease, a shorter DFS was associated with worse OS, and the use of cisplatin was associated with better OS. For the patients with metastases at diagnosis, a high-risk Bajorin score and the use of carboplatin were associated with worse outcomes.