Urothelial cell carcinoma of the bladder in pediatric patients: A comparison with adults from the National Cancer Database

PURPOSE: Urothelial cell carcinoma of the bladder (UCCB) is a common malignancy in adults but is rarely seen in children. Due to its rarity in the pediatric population, we utilized a national database to compare demographics, tumor characteristics, staging, and outcomes among pediatric patients, young adults (YA), and older adults (OA). MATERIALS AND METHODS: We performed a retrospective cohort study using the National Cancer Database (NCDB) to identify patients diagnosed with UCCB (ICD-O-3 histology codes 8120-8131) from 2004 to 2020. Patients were grouped as Pediatric (≤21 years), Young Adult (22-50 years), and Older Adult (>50 years). Cases with missing survival data were excluded. We analyzed demographic data, tumor stage, treatment, and overall survival using chi-square tests, Kaplan-Meier survival estimates, and Cox regression models. RESULTS: We identified 235 pediatric (0.1 %), 22,034 YA (4.3 %), and 488,182 OA (95.6 %) cases. Among pediatric cases, 64 % were male, and most were non-Hispanic white. Non-muscle-invasive bladder cancer (NMIBC; Stage Ta, Tis, T1) was present in 96.2 % of pediatric cases, compared to 3.8 % having muscle-invasive disease (MIBC; Stage T2-T4). Pediatric patients had superior 1-, 2-, 5-, and 10-year survival rates compared to older cohorts. Across all age groups, invasive disease was associated with worse outcomes. Surgery was the primary treatment for 98.3 % of pediatric patients, with 19.6 % receiving intraoperative or adjuvant chemotherapy, compared to 31.7 % in the YA group and 33.1 % in the OA group. Treatment approaches depend largely on muscle-invasive status and have evolved over time. CONCLUSIONS: This is the most extensive study to date on pediatric UCCB, revealing a predominance of NMIBC and improved survival rates in children compared to adults. Pediatric patients were less likely to receive chemotherapy despite high surgical rates. These findings underscore the need for further research to inform the development of standardized treatment for pediatric UCCB.