Table 5.
RCTs examining the effect of green tea and/or GTC supplementation on PSA concentrations among men with PCa or increased PCa risk.
| First Author | Origin | Masking | Duration | Patients | Interventions | Results |
|---|---|---|---|---|---|---|
| Henning † [107] | US | Open-label | d-33, d-31, and d-29, respectively in each group | n = 93 men diagnosed with PCa before radical prostatectomy | 1. 6 cups/d of brewed green tea (n = 34) 2. 6 cups/d of black tea (n = 26) 3. 6 cups/d of water (control) (n = 33) |
A small decrease was noted in serum PSA concentrations among green tea drinkers, compared with the controls. |
| Nguyen [108] | US | Double-blind | 3–6 wks until prostatectomy | n = 50 men with a PCa diagnosis scheduled for prostatectomy | 1. PolyE ∂ (800 mg EGCG) (n = 25) 2. Placebo (n = 25) |
No difference was noted in PSA concentrations between groups. |
| Wang [109] | US | NR | 3–6 wks until prostatectomy | n = 17 men with clinically localized PCa | 1. 6 cups green tea/d (n = 8) 2. 6 cups water/d (n = 9) |
PSA results were not reported. |
| Kumar [110] | US | Double-blind | 1 yr | n = 97 men with HGPIN and/or ASAP | 1. PolyE ∂ (a mixture of GTCs with 400 mg EGCG)/d (n = 49) 2. Placebo (n = 48) |
A decrease in serum PSA was observed on the PolyE arm. |
| Bettuzzi [111] | IT | Double-blind | 1 yr | n = 60 men with HGPIN | 1. 3 × 200 mg GTCs caps 2. Placebo |
PSA did not change between the two arms. |
| Micali † [112] | IT | Double-blind | 1 yr | n = 44 patients with HGPIN | 1. GTCs (600 mg/d) (n = 22) 2. Placebo (n = 22) |
A reduction was noted in PSA of the GTCs arm at 6 and 12 mo. |
ASAP, atypical small acinar proliferation; CI, confidence intervals; EGCG, (-)-epigallocatechin-3-gallate; GTCs, green-tea catechins; HGPIN, high-grade prostatic intraepithelial neoplasia; PCa, prostate cancer; PolyE, polyphenon E; PSA, prostate-specific antigen; RCT, randomized controlled trials. † phase II trial; ∂ contains 85–95% total catechins, 56–72% as EGCG, and <1.0% caffeine.