Cystoscopy and the development of invasive bladder cancer in patients presenting with superficial urinary bladder cancer

The objective of this study was to determine the impact of different follow-up cystoscopy frequencies on time to development of invasive bladder cancer in a cohort of 3,658 eligible patients 65 and older with an initial diagnosis of superficial bladder cancer between 1994 and 1998. Bladder cancer patients in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database were used as the study population. ^ It was hypothesized that superficial bladder cancer patients receiving less frequent cystoscopy follow-up would develop invasive bladder cancer sooner after initial diagnosis and treatment than patients seen more frequently for cystoscopy follow-up. Cox Proportional Hazard Regression revealed that patients seen for cystoscopy every 3 or more months were 83–89% less likely to develop invasive cancer than patients seen every 1 to 2 months. A comparison of the 2 groups (1 to 2 months vs. 3≥ months) revealed that the 1 to 2 month group may have had more aggressive disease, and they are seen more frequently as a result. ^ These findings suggest that there are two groups of superficial bladder cancer patients: those at high risk of developing invasive bladder cancer and those at low risk. Patients who developed invasive bladder cancer sooner after initial diagnosis and treatment were seen more frequently for cystoscopy follow-up. The recommendation is that cystoscopy should be based on disease status at 3 months. Standardized schedules give all patients the same number of cystoscopies regardless of their risk factors. This could lead to unnecessary cystoscopies in low risk patients, and fewer than optimal cystoscopies in high risk patients. ^