The randomized controlled trial (RCT) remains the gold standard for informing evidence-based clinical practice, in urology as in other medical domains. Limitations include time, significant expense, stringent inclusion criteria, and resistance to randomization by clinicians and patients. Ultimately, if patients enrolled in a RCT differ from the larger population of patients with a given condition, the external validity of the findings may be questionable. Although these limitations can be mitigated by utilizing specialized RCT designs (Table ), disease registries have emerged as an important complement to RCTs. Disease registries, which accrue prospectively identified cohorts and follow them regardless of sociodemographic characteristics, clinical variables, treatment details or intermediate outcomes, have emerged as an important complement to RCTs. This reflection of “real world” treatment is a tremendous asset especially in prostate cancer research as it provides a relatively cost-effective tool to shed light on a disease with a long natural history and rapidly changing management practices that are subject to many different clinical, scientific, demographic, and economic dynamics. This article will highlight some advantages of disease registries focusing on the example of prostate cancer and the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE™) registry.
Specialized classifications of randomized controlled trials
CaPSURE was initiated in 1995 to document national trends in prostate cancer epidemiology, disease management, oncologic outcomes, and health-related quality of life (HRQOL) outcomes. It is a longitudinal, observational database accruing data from a total of 40 urologic practice sites over the history of the registry. The majority of sites are community based, although four university-affiliated centers, and Veterans Affairs (VA) medical centers are included. Men with biopsy-proven cancer are invited to join CaPSURE regardless of disease stage or treatment history. Informed consent for participation is obtained under institutional review board supervision.
CaPSURE collects approximately 1,000 clinical and patient-reported variables. Clinical information is collected by the treating urologist at baseline and with each follow-up visit and includes history of prostate cancer diagnosis, biopsies, pathology, staging tests, primary and subsequent treatments (radical prostatectomy [RP], external beam radiotherapy [EBRT], brachytherapy, primary and neoadjuvant androgen deprivation therapy [PADT and NADT], cryosurgery, and watchful waiting/active surveillance [AS]), Karnofsky performance status scores, clinic procedures, and medications. At enrollment and every 6 months thereafter, a questionnaire is completed documenting sociodemographic parameters, comorbidities, and HRQOL using validated instruments. Other sections of the patient questionnaires assess use of health services, with hospitalization data verified by discharge summary review.
Patients are treated according to their physicians’ usual practices and patient preferences and are followed until time of death or withdrawal from the study. Periodic, random sample chart review ensures completeness and accuracy of data collected and entered. Additional details regarding project methodology have been reported previously [1
]. CaPSURE is managed by the Department of Urology at the UCSF Helen Diller Family Comprehensive Cancer Center. It was funded from inception to 2007 through an unrestricted education grant from TAP Pharmaceutical Products, Inc., and currently is supported through Abbott Labs (Chicago, IL) and several collaborative Federal grants.
There are currently 13,821 men enrolled in CaPSURE. The median patient age at diagnosis is 67, and 75% of men are between 60 and 79 years of age. Most patients are white, with approximately 10% black representation, and 3.5% Latino, Asian, and other ethnicities. There is a fairly even distribution across socioeconomic strata, based on education and income level. CaPSURE has yielded over 130 peer-reviewed publications, with several others in press. A summary of some key research findings follows.