Clinical characteristics and treatment outcomes of patients with small cell carcinoma of the urinary bladder.

Background: Small cell carcinoma of the urinary bladder (SCUB) is rare. The optimal treatment for SCUB remains unclear. To address the problem of appropriate treatment for each case, we assessed single-modality and surgery-based multimodality treatments in patients with SCUB.

Materials and methods: We retrospectively reviewed the medical records of 12 patients with SCUB between 1990 and 2013. All patients underwent transurethral resection of the bladder tumor and were diagnosed with SCUB. Their clinicopathological characteristics were assessed, and the outcomes were compared according to the treatment modality.

Results: The median (range) age at diagnosis was 66 years (range, 53-85 years). T1-4N0M0 was observed in 8 patients (66%), N1-3M0 in 2 (17%), and NanyM1 in 2 (17%). After transurethral resection of the bladder tumor, 6 patients (50%) underwent cystectomy alone, and 4 (33%) underwent cystectomy and presurgical or adjuvant chemotherapy with etoposide and cisplatin. During the median follow-up period of 20.7 months, 6 patients (50%) died of cancer, and 2 patients (17%) died of other causes. The median overall survival period was 1.9 years. The 5-year overall survival rate in patients who underwent cystectomy and chemotherapy was 75%, whereas that in those who underwent cystectomy alone and transurethral resection alone were 22% and 0%, respectively (p = 0.012). Recurrence-free survival was significantly correlated with cause-specific survival (r = 0.95; 95% confidence interval, 0.81-0.99; p < 0.001).

Conclusions: Radical cystectomy with chemotherapy using the etoposide and cisplatin regimen improved the prognosis of patients with SCUB and TxNxM0. The time from initial progression to death due to cancer was very short, indicating that the initial treatment strategy is crucial.