Predictors of upper tract urothelial cell carcinoma after primary bladder cancer: a population based analysis.

PURPOSE: Upper tract tumors occur in 2% to 7% of patients after primary bladder cancer, making surveillance upper tract imaging part of bladder cancer management. We determined the cumulative incidence of secondary upper tract tumor development after primary bladder cancer and risk factors for secondary upper tract tumors using contemporary population based data.
MATERIALS AND METHODS: We identified patients with bladder cancer in the Surveillance, Epidemiology, and End Results cancer registry from 1988 to 2003. All subsequent cases of upper tract tumors were ascertained. Multivariate Cox survival analysis was performed to evaluate risk factors for secondary upper tract tumors after adjusting for age, race, gender, stage, grade, tumor location, surgical management, year of diagnosis and tumor registry.
RESULTS: Of 99,338 patients with bladder cancer upper tract tumors developed in 768 (0.8%). The median time to secondary upper tract tumors was 33 months. Of upper tract tumors 71% developed within 5 years of bladder cancer diagnosis and only 6% developed more than 10 years after diagnosis. On multivariate analysis high grade (HR 2.16, 95% CI 1.71-2.74) and nonmuscle invasive disease (Ta, T1) (HR 1.16, 95% CI 0.97-1.39) were predictive of upper tract tumor recurrence. Upper tract disease was more likely to develop in patients with tumors at the trigone/ureteral orifice (HR 1.76, 95% CI 1.48-2.09).
CONCLUSIONS: Upper tract tumors developed in 0.8% of patients with bladder cancer. Although late cases occurred, upper tract tumors developed in the majority of cases within 3 years. Pathological factors such as tumor grade, stage and location were predictive of upper tract recurrence. These findings may be useful for tailoring surveillance protocols in patients with bladder cancer.