Disease specific mortality in patients with low risk bladder cancer and the impact of cystoscopic surveillance.

PURPOSE: We determined the risk of disease specific mortality in patients with primary, low risk, noninvasive (G1pTa) bladder cancer and compared it to disease specific mortality in age and gender matched general populations.
MATERIALS AND METHODS: We identified all patients with primary low risk cancer at our institution. We excluded those with adverse pathological features and then matched histopathology, pharmacy, hospital episode and Cancer Registry records. We reviewed case notes on patients with subsequent muscle invasion (progression) or disease specific mortality. Patients underwent post-resection surveillance and treatment using standard regimens. National and regional disease specific mortality rates were calculated from appropriate data.
RESULTS: A total of 699 patients met study inclusion criteria. Median followup was 61 months (IQR 24-105). Of the patients 17 (2.4%) died of bladder cancer, including 13 of 14 with progression to muscle invasion and 4 of 19 with grade progression to high grade, nonmuscle invasive disease. On Cox regression analyses low grade dysplasia in the initial resection specimen and tumor weight were associated with disease specific mortality (p <0.003). Disease specific mortality in these patients was 5 times the background rate in matched populations. Limitations of this study include its retrospective nature and the low frequency of adverse events.
CONCLUSIONS: Patients with low risk bladder cancer rarely progress to muscle invasion but they are at higher risk for disease specific mortality than the general population. Current surveillance regimens appear ineffective for detecting progression in time to alter prognosis.