Green tea extract tested to keep prostate cancer in check

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * 18 years of age or older * Biopsy-proven (consisting of ≥ 12 tissue cores) adenocarcinoma of the prostate with cancer present in at least one biopsy core (TRUS or/and mpMRI/TRUS fusion), Gleason score (3+3) or predominant Gleason pattern 3 (3+4), ≤ 33% of biopsy cores, and ≤50% involvement of any biopsy core (Participant meets all criteria for Active Surveillance as determined by MD) * Willing to start or continue on active surveillance * Baseline/screening serum PSA \<10 ng/mL * No other prior treatment for PCa, including focal therapy * ECOG performance status 0-1 * No history of renal or hepatic disease, including history of hepatitis B and C * Meet hematological eligibility parameters (Neutrophil count ≥ 1,200/mm3 (≥1.2 k/μL), Stable platelet count ≥ 75,000/mm3 (≥ 75k/μL) Hepatic and renal function eligibility parameters, serum total Bilirubin ≤ULN (ULN: 1.2 mg/dl) (or ≤3.0 mg/dL for patients with Gilbert's syndrome), AST or ALT \<1.5x ULN and Serum creatinine ≤1.5 x ULN * Willing to abstain from consumption of any supplements containing GTC * Willing to restrict tea consumption to less than three (3) servings of hot tea or three (3) servings of iced tea per week * Willing to discontinue current vitamin/mineral supplement use and use one provided by study * Willing to take study agent or placebo at the dose specified with meals. Exclusion Criteria: * Have had prior treatment for PCa by surgery, irradiation, local ablative (i.e., cryosurgery or high-intensity focused ultrasound), or androgen-deprivation therapy) * Men who are currently treated or those treated in the past 3 months prior to day of randomization with 5- alpha-reductase inhibitors (e.g., finasteride, dutasteride) * Participants who have PCa with distant metastases * Participants who have been treated with: hormone therapy, immunotherapy, chemotherapy and/or radiation, for any malignancies within the past 2 years prior to registration.Patients with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial. All patients with metastatic disease will be excluded * Participants may not be receiving any other investigational agents * History of allergic reactions attributed to tea or compounds of similar chemical or biologic composition to green tea extracts.