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.