Bladder malignancies in children aged <18 years: results from the Surveillance, Epidemiology and End Results database

OBJECTIVE To present descriptive statistics for bladder tumours in children, calculated from the Surveillance, Epidemiology and End Results (SEER) database, as bladder malignancies are relatively uncommon in children, causing difficulty in understanding their incidence and survival. PATIENTS AND METHODS The SEER database was interrogated to report the incidence of bladder malignancies in children from birth to 18 years old. Race and sex differences were assessed. The 5-year survival by disease stage at diagnosis and 5-year conditional survival after surviving for 1-3 years is reported for 1973-2003. The incidence and survival rates for bladder embryonal rhabdomyosarcoma were further characterized. RESULTS We identified 140 cases of bladder cancers in the selected cohort. Papillary urothelial neoplasm of low malignant potential (PUNLMP) and rhabdomyosarcoma comprised 50.7% and 36.4% of the tumours, respectively. The incidence of bladder malignancies significantly increased between 1973 and 2003. Conditional survival calculated for 1 and 2 years after disease diagnosis was 93.6% and 97.5%. Fifty-one cases of embryonal rhabdomyosarcoma were identified. The male to female incidence ratio was approximate to 2:1 for these tumours. The 5-year survival rates were 50-80% over the past three decades. CONCLUSIONS We present the most contemporary survey of the SEER database for the incidence and survival for bladder tumours in children. Depending on the patient's age, PUNLMP and rhabdomyosarcoma predominated in different proportions. The 2-3-year conditional survival and overall survival were excellent. We also identified improving survival for embryonal bladder rhabdomyosarcoma with time.