Study finds more intensive treatment not associated with better outcomes in early bladder cancer - though experts warn on over interpreting results

Patients with early bladder cancer who receive more intensive treatment within the first two years of diagnosis do not appear to have better survival than patients who receive less intensive treatment, according to a retrospective analysis published in the Journal of the National Cancer Institute.

Although bladder cancer is the fifth most common cancer in the United States, optimal treatment strategies for the disease remain unclear and there are relatively few data available from randomized controlled clinical trials. Current treatment guidelines favour more intense surveillance and therapy, but individual urologists vary in their approach to treatment.

In the current study, Dr Brent Hollenbeck, of the University of Michigan Health System in Ann Arbor, and colleagues used the Surveillance, Epidemiology, and End Results database and linked patient information in the Medicare database to determine whether more intensive early treatment was associated with better outcomes. The investigators identified 20,713 patients diagnosed with early bladder cancer between 1992 and 2002. They estimated the intensity of treatment based on Medicare costs in the first two years following diagnosis and then divided the 940 treating physicians into four groups based on their average cost of treatment.

The average cost of care for early bladder cancer was $2,830 in the least treatment-intense group compared with an average cost of $7,131 in the most treatment-intense groups. More intensive treatment was not associated with better overall survival. Patients who underwent more intensive early treatment were more likely to undergo major interventions later.

“The high–treatment intensity style of practice was characterized by a greater use of all measured health services, including intravesical therapy, endoscopy, urinary studies, and imaging,” the authors write. “However, this aggressive early treatment approach did not improve survival or prevent patients from having to undergo major medical interven­tions in subsequent years. In fact, compared with patients treated by low–treatment intensity urologists, those treated by high–treatment intensity urologists were nearly two and one-half times more likely to undergo radical cystectomy and nearly twice as likely to receive any major medical intervention, even after accounting for patient differences.”

In an accompanying editorial, Gary H. Lyman, M.D., and colleagues of Duke University School of Medicine in Durham, point out that retrospective studies based on healthcare claims need to be interpreted with caution. Important clinical information, which affects treatment decisions, may not be included in such databases. Additionally it is impossible to adjust for unmeasured factors which might influence the results: "The apparent association between provider treatment intensity defined as greater average bladder cancer expenditures and worse bladder cancer–specific but not overall survival is more likely the result of confounding by unavailable prognostic factors than the result of adverse events resulting from the procedures themselves."

Article: Hollenbeck B et al. Provider Treatment Intensity and Outcomes for Patients With Early-Stage Bladder Cancer, J Natl Cancer Inst 101:571-580.http://www.eurekalert.org/jrnls/jnci/101-08-Hollenbeck-djp039.pdf

Editorial: Lyman G et al. Does Treatment Intensity Matter in Superficial Bladder Cancer? Consensus, Clinical Practice, and Confounding J Natl Cancer Inst 101:543-545.http://www.eurekalert.org/jrnls/jnci/101-08-Lyman-djp060.pdf