The Prevalence of Bladder Cancer During Cystoscopy for Asymptomatic Microscopic Hematuria

Abstract

Objective: To investigate the rate of bladder cancer in patients undergoing cystoscopic evaluation for asymptomatic microscopic hematuria (AMH) in order to identify groups at sufficiently low-risk for bladder cancer in whom invasive testing may be avoided.

Methods: We performed a retrospective review of patients who underwent cystoscopic evaluation for AMH between 2010 and 2018. Age, gender, smoking status, history of pelvic radiation, and number of red blood cells per high-power field on urine microscopy were recorded. We used logistic regression to explore the association between specific risk factors and a diagnosis of bladder cancer on cystoscopy.

Results: Among the 2118 patients who underwent cystoscopy for AMH, 25 patients (1.2%) were diagnosed with a bladder cancer, all of which were nonmuscle invasive urothelial carcinoma. There were no bladder cancers detected in patients under the age of 50. Older age and positive smoking history were significantly associated with bladder cancer.

Conclusion: Bladder cancer was an uncommon finding on cystoscopy among patients being evaluated for AMH, especially in younger patients. We confirmed several known risk factors for bladder cancer, including older age and smoking history. Further studies are required to evaluate the utility of cystoscopy for identifying latent bladder cancers in low-risk patients.