Purpose: Use of longitudinal clinical data bases that assess health care utilization and QOL are ideal for assessing effects of various treatments and medical decisions on outcomes and also on patient health-care burden. We compared health care utilization and costs of 4,424 newly diagnosed prostate cancer patients by type of treatment (controlling for disease risk) for up to 10 years. We also compared health care utilization by year of diagnosis, to determine if disease burden changed over time for the same risk group. Methods: Data from, CaPSURE™ (Cancer of the Prostate Strategic Urological Research Endeavor) which is a national longitudinal database registry of men with all stages of biopsy-proven prostate adenocarcinoma was used for the study. Patients are recruited from 31 academic and community-based urology practices across the United States by participating urologists who report clinical data and follow-up information on diagnostic tests and treatments. Patient-reported quality of life and utilization of services, including physician visits, long term care, medication use, diagnostic tests, and work history. Begun in 1995, data is collected every 3-6 months. Disease risk was defined using serum PSA, Gleason score, and T-stage. We compared radical prostatectomy, cryotherapy, brachytherapy, radiation, and hormonal therapies using ANOVA with Duncan Waller and GLM with Tukey's multiple comparison tests. Results: Number of hospitalizations and length of stay differed by type of primary treatment (F = 34.54, df = 44, p<0.01 & F=336.32, df = 44, p<0.01 respectively). Averaged over up to 54 months, both number (0.26-0.32) and LOS, as well as visits to urologists and oncologists differed significantly by disease risk and type of therapy (p < 0.01). Patients using radiation therapy had the most physician visits (6.73). Hospitalization rates decreased over time from 33% during the first 6 months to 10-11% until 42 months and (8-10%) until 54 months. Health care utilization differed by year of diagnosis, with a significantly higher proportion of patients (2-3 times more) having a hospitalization in 2002/2003 than in 1994 (p<0.01). Conclusions: The use of PSA testing and new treatments are thought to lead to earlier diagnosis and earlier more aggressive treatments, and our study demonstrates that health utilization also follows this pattern with progressively higher resource use for prostate disease diagnosed from 1995 to 2003.