Biomarker 11-dh-TXB2 in Blood and Urine Samples From Patients With Prostate Cancer and Healthy Volunteers

DISEASE CHARACTERISTICS: * Meets one of the following criteria: * Histopathologically confirmed prostate cancer meeting 1 of the following criteria: * Newly diagnosed untreated disease * Received prior local therapy (prostatectomy, definitive radiotherapy, brachytherapy, or cryotherapy) with no evidence of disease activity (defined as serum PSA \< 0.4 ng/mL post therapy) and by imaging studies * Experienced biochemical failure (defined as rise in serum PSA ≥ 0.4 ng/mL post therapy) * Healthy volunteer (clinic patient with no history of clinically significant malignancies within the past 6 months) PATIENT CHARACTERISTICS: * No clinical evidence of liver cirrhosis or chronic liver disease (i.e., evidence of ascites or severe coagulopathy) * No active prostatitis PRIOR CONCURRENT THERAPY: * See Disease Characteristics * More than 30 days since prior and no concurrent regular antiplatelet agents (including aspirin, anagrelide, cilastazole, clopidogrel, dipyridamole, pentoxiphylline, sulfinpyrazone, or ticlopidine) * More than 7 days since prior and no concurrent NSAIDs (including ibuprofen, celecoxib, diclofenac, diflunisal, etodolac, fenoprofen, flurbiprofen, indomethacin, ketoprofen, meclofenamate, mefenamic acid, nabumetone, naproxen, oxaprozin, piroxicam, sulindac, or tolmetin)