Radiation Therapy as Definitive Local Treatment in Patients with Limited-Stage Small Cell Carcinoma of the Bladder: Does total dose matter?

Purpose: To determine whether total radiation dose affects survival outcomes for patients with small cell carcinoma of the bladder (SCCB). Methods: We queried the National Cancer Database (NCDB) for patients with limited stage SCCB undergoing multimodality treatment and retrospectively analyzed survival outcomes according to total radiation dose received. Results: Patients aged 41-79 receiving a total radiation dose of 54 Gy or greater had a significant improvement in overall survival compared to those receiving less than 54 Gy, with a median overall survival of 58.9 months (95% confidence interval [CI] 37.2-80.6 months) compared to 21.5 months (95% CI 15.2 - 27.8 months) (p < 0.05). There was no difference in outcomes for patients receiving between 54 and 60 Gy compared to those receiving 60 Gy or higher. There was also no difference in outcomes based on total radiation dose for patients 80 years and older. Conclusions: For patients aged 79 or younger with limited stage SCCB, total radiation dose of 54 Gy or greater is associated with better overall survival.