Bladder cancer incidence rates and trends in young adults aged 20-39 years.

Objectives: To assess contemporary gender, race and stage-specific incidence and trends of bladder cancer among young adults in the United States.
Materials and Methods: Within Surveillance, Epidemiology, and End Results database (2001-2016), all patients aged 20 to 39 years-old with histologically confirmed bladder cancer were included. Age-standardized rates (ASR per 100,000 person-years) were estimated. Temporal trends were calculated through joinpoint regression analyses to describe the average annual percent change (AAPC).
Results: From 2000 to 2016, 2,772 new cases were recorded (ASR 0.2, AAPC -1.5%, P = 0.01). ASRs were higher in males than in females (0.3 and 0.1, respectively) and decreased significantly in both genders (AAPC -1.3, P = 0.02 and -2.2% P = 0.03, respectively). non-Hispanic White (NHW) accounted for 70.7% of the cohort and had the highest incidence (ASR 0.3) that decreased over time (AAPC -1.4%, P = 0.02). Conversely, ASRs in other ethnic groups were lower and showed stable trends. The most frequent tumor characteristics were Ta/TisN0M0 stage (71.0%, ASR 0.1, AAPC -1.0%, P = 0.1), low grade (61.6%, ASR 0.1, AAPC -4.3%, P = 0.001) and urothelial histology (95.5%, ASR 0.2, AAPC -1.5%, P = 0.01).
Conclusions: Despite the rarity of bladder cancer in those aged 20 to 39 years, a standard work-up is required to avoid advanced stage at diagnosis. The current data validate initial diagnoses at earliest stage in the vast majority of young adults. Moreover, decreasing ASRs in both genders are encouraging.
Competing Interests: Conflict of interest All the authors declare no potential conflict of interest to disclose.
(Copyright © 2020 Elsevier Inc. All rights reserved.)