At the baseline/randomization visit, a QOL (Medical Outcomes Study Short Form-36) and lower urinary tract symptoms (LUTS) score assessment will be completed; urine and serum will be collected for measurement of diagnostic markers; plasma will be collected for measurement of baseline catechin levels; serum will be collected for banking; and diet recall forms will be collected. Participants will be equally randomized to blinded treatment with either Polyphenon E 200 mg EGCG bid or matching placebo, and an initial supply of study drug will be dispensed. All participants will also be provided with a standard multivitamin/mineral supplement to assure consistent, appropriate nutrient intake among study participants. The planned intervention period is 12 months; participants will return for monthly clinic visits during the intervention period. At each monthly clinic visit, blood will be drawn for repeat hepatic function panel, lactate dehydrogenase (LDH) and prothrombin time/partial thromboplastin time (PT/PTT), and participants will be interviewed to review and capture information from study agent intake log (pill count), assess signs and symptoms and concomitant medications; additional study medication will be dispensed as needed. After 3 and 6 months of intervention, blood will be drawn for serum chemistry and hematology, and LUTS and QOL assessments will be performed. In addition, at the 6 month visit, two-day diet recall forms will be collected, blood will be drawn for plasma catechin measurements and serum banking, serum and urine will be collected for diagnostic marker measurement, and repeat digital rectal exam (DRE) and prostate specific antigen (PSA) will be performed. If there is a palpable prostate nodule or confirmed PSA increase (>0.75 ng/ml) at 6 months, a repeat biopsy will be performed. If the 6-month biopsy shows evidence of disease progression, participants will stop intervention and proceed to the post-intervention assessment; otherwise, intervention will continue through month 12. At the end of intervention (maximum of 12 months), a repeat prostate biopsy will be performed for post-intervention endpoint measurements. In addition, the physical exam and DRE, LUTS and QOL will be repeated, and 2-day diet recall forms will be collected. Blood will be drawn for serum chemistry and hematology, PSA, hepatic function panel, LDH, PT/PTT; serum and urine will be collected for diagnostic marker measurement; plasma will be collected for catechin measurements; and serum will be collected for banking. Participants will be interviewed to review and capture information from study agent intake log (pill count), assess signs and symptoms and concomitant medications.