Clinical effectiveness (CE) research for the treatment of men presenting with clinically localized prostate cancer is evolving. Comparable outcomes following radical prostatectomy (RP), intensity modulated radiation therapy (IMRT), and brachytherapy (BT) are difficult to generalize without risk-stratification based on central pathologic review. The purpose of this study is to analyze outcomes of patients treated with radical prostatectomy (RP), intensity modulated radiation therapy (IMRT), and brachytherapy (BT) at a single tertiary cancer center. From January 2000 thru December 2001, an IRB-approved retrospective analysis was performed on 745 men at the M.D. Anderson Cancer Center (MDACC). Patients presenting with clinical T1-T3 disease and Gleason score (GS) 6-10 disease were treated with either RP (n = 388), IMRT (n = 254), or BT (n = 103). Kaplan-Meier estimates were used to determine the time to recurrence (TTR) and prostate cancer specific survival (PCSS). The Cox proportional hazards regression model was used to estimate the hazard ratios for predetermined potential prognostic factors for TTR and PCSS. These factors were modeled in a univariate and multivariate model to examine contribution to differences between the groups. The median follow-up was 7.2 years for RP, 7.2 years for IMRT, and 7.6 years for BT. The IMRT group had significantly higher mean PSA, biopsy Gleason score, clinical T stage, and risk grouping. On univariate analysis, factors associated with a shorter TTR include T2 or T3 clinical stage (p < 0.0001), high (p < 0.001), or intermediate (p < 0.01) risk group, PSA greater than 10 ng/mL (p < 0.001), Gleason 4+3 versus 3+4 (p < 0.001), and treatment with IMRT (p = 0.015). On multivariate analysis, significant factors for TTR were PSA greater than 10 ng/mL (HR = 4.29, p = 0.004) and T2 (HR = 3.26; p < 0.001) or T3 (HR = 2.84; p = 0.05) clinical stage. 5 year PCSS was 99.7% for RP, 100% for BT, and 98.3% for IMRT. For PCSS, the only statistically significant factor on univariate analysis was high risk group (p = 0.028). On multivariate analysis, no factors reached significance for PCSS. At MDACC, low and intermediate risk prostate cancer patients have similar PCSS and TTR when treated with RP, IMRT, or BT. Additional factors such as patient satisfaction, quality of life, and cost-benefit analyses will enhance clinical effectiveness research for prostate cancer treatment.
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