Locoregional small cell carcinoma of the bladder: clinical characteristics and treatment patterns

Because small cell carcinoma of the bladder is a relatively rare tumor type, literature about its treatment remains limited. We determined patterns of care and survival after treatment in what is to our knowledge the largest series to date of patients with locoregional small cell carcinoma of the bladder.

We identified patients with localized/locally advanced (cTis-cT4, cN0 or cM0) bladder small cell carcinoma diagnosed between 1998 and 2010 from the National Cancer Database (NCDB). Treatment was categorized as bladder preservation therapy, radical cystectomy alone, bladder preservation therapy with multimodal treatment or radical cystectomy plus multimodal treatment. We performed Kaplan-Meier overall survival analysis to evaluate differential survival between treatment groups.

A total of 625 patients met study inclusion criteria. Median age at diagnosis was 73 years (range 36 to 90) and 65% of patients presented with cT2 disease. Patients were treated with bladder preservation therapy (174 or 27.8%), bladder preservation therapy plus multimodal treatment (333 or 53.3%), radical cystectomy alone (46 or 7.4%) and radical cystectomy plus multimodal treatment (72 or 11.5%) with a 3-year overall survival rate of 23% (95% CI 15-32), 35% (95% CI 30-45), 38% (95% CI 17-60) and 30.1% (95% CI 16-47), respectively. Overall survival was most favorable for radical cystectomy alone plus neoadjuvant chemotherapy with a 3-year rate of 53% (95% CI 19-79).

In the United States locoregional small cell carcinoma of the bladder develops predominantly in white males, in whom treatment is performed at metropolitan, comprehensive community cancer centers. Most patients were treated with bladder preservation therapy and most received multimodal therapy. Patients who received neoadjuvant chemotherapy followed by radical cystectomy had the most favorable survival.