The Inter-SPORE Prostate Biomarkers Study (IPBS) was established to prospectively collect and analyze biological specimens to predict and validate outcomes after treatment for prostate cancer. The study population will consist of patients scheduled to receive standard of care therapy for localized prostate cancer, either radical prostatectomy (RP) or radiation therapy (XRT; includes external beam radiation, brachytherapy, or both). Seven hundred (700) patients (350 RP, 350 XRT) will be recruited from 11 SPORE sites over a two-year interval. We will collect serum, plasma, lymphocytes, and prostate tissue samples for distribution to collaborating biomarker validation sites at other prostate SPOREs, along with clinical and epidemiologic data.