Symptomatic brain metastases from small-cell carcinoma of the urinary bladder: The Netherlands Cancer Institute experience and literature review.

BACKGROUND The incidence of symptomatic brain metastases in small-cell carcinoma of the urinary bladder (SCBC) is unknown. This precludes advice about prophylactic cranial irradiation (PCI). PATIENTS AND METHODS The medical records of all patients with SCBC seen at The Netherlands Cancer Institute from 1993 to 2009 (n = 51) were reviewed. Limited disease (LD) was defined as any pT, cN₀₋₁, and cM₁. Patients with LD were offered bladder-preserving treatment involving combined chemoradiotherapy. Patients with extensive disease (ED) were treated with palliative chemotherapy. PCI was not applied in any patient. RESULTS Among 39 patients with LD, median disease-specific survival was 35 months. Four developed symptomatic brain metastases after a median follow-up of 15 months (range 3-24) and were treated with whole-brain radiotherapy. No patient with ED developed symptomatic brain metastases during a median follow-up of 6 months. The reported incidence of brain metastases in SCBC in the literature ranges between 0% and 40%. On the basis of all reported series, the pooled estimate of the cumulative incidence of brain metastases is 10.5% (95% confidence interval 7.5% to 14.1%). CONCLUSIONS The incidence of symptomatic brain metastases from SCBC is significantly lower than that from small-cell lung cancer. Therefore, we do not routinely advise PCI in patients with SCBC.