Abstract B67: Effect of polyphenon E on progression to prostate cancer after diagnosis of high-grade prostatic intraepithelial neoplasia or atypical small acinar proliferation in African American men
Authors: KUMAR Nagi , Schell Michael , Chornokur Ganna , Phelan Cathy 
Published: October 2015

Importance: Studies suggest that green tea catechins are worthy of investigation for prostate cancer (PCa) chemoprevention. AAM diagnosed with HGPIN had significantly elevated PCa risk, compared to AAM without HGPIN (83.3% vs 6.9%, p=0.0001). However, to date, there are no chemoprevention trials with GTC targeting a substantial number of AAM diagnosed with HGPIN, who have an exceptional risk for progression to aggressive prostate cancer.

Objective: To determine whether the daily consumption of a standardized formulation of green tea catechins (Polyphenon E) supplement for 1 year reduces the rate of progression to PCa in men diagnosed with HGPIN or ASAP with a specific focus on AAM. Additional objectives were to evaluate tolerance, lower urinary tract symptoms (LUTS) and quality of life (QOL).

Design, setting and participants: A randomized, double-blinded trial was conducted from September 2008 to March 2014 at 3 medical centers in the US targeting 97 men (including 20 AAM) diagnosed HGPIN or ASAP, randomized to treatment (n=49) or placebo arm (n=48). Supplement or placebo was initiated within 6 months of initial biopsy and continued for 1 year.

Intervention: Participants were block randomized by baseline diagnosis to receive Polyphenon E (PolyE), a decaffeinated, standardized green tea catechin mixture, the main component of which is (−)-epigallocatechin-3-gallate (EGCG) at a dose of 400 mgs EGCG per day (200 mgs twice a day [BID]), or placebo.

Main outcomes and measures: Rate of progression to PCa at one year in men treated with PolyE or placebo following diagnosis of HGPIN or ASAP; evaluation of tolerance, LUTS and QOL.

Results: Overall, we did not observe a difference in the number of men who progressed to PCa in one year in the Poly E (4/49) arm compared to placebo arm(6/48). Among men with baseline diagnosis of HGPIN, a significantly greater number of subjects progressed to ASAP in the placebo arm (5/25) compared to men in the GTC arm (0/26; P &lt;0.05). Specifically evaluating the effect of GTC in 20 AAM in this trial, results reveal that 2/12 (17%) AAM progressed to PCa in the placebo arm compared to 0/8 (0%) AAM receiving GTC. In subjects with baseline diagnosis of HGPIN, 3/9 men progressed to ASAP or PCa compared to 0/6 the GTC arm with no safety concerns. Post treatment serum tPSA was reduced in AAM on GTC (2.8ng/ml) compared to placebo (5.6ng.ml). No significant differences in tolerance, LUTS or QOL were observed between the two groups.

Conclusions and Relevance: Daily intake of a standardized, decaffeinated catechin mixture containing 400 mgs EGCG (200 mgs BID) for 1 year is well tolerated and appears to produce chemoprevention effects in the early stages (HGPIN to ASAP). Targeting earlier stages of disease using chemoprevention agents with a favorable safety profile to prevent progression to clinically evident aggressive PCa may be key to eliminating disparity in PCa morbidity and mortality in the exceptionally high risk population of AAM. These findings should be confirmed in a phase III clinical trial prior to recommending use in clinical settings.

Trial Registration: Clinical Trials.gov Identifier: NCT00596011

Citation Format: Nagi KUMAR, Michael Schell, Ganna Chornokur, Cathy Phelan. Effect of polyphenon E on progression to prostate cancer after diagnosis of high-grade prostatic intraepithelial neoplasia or atypical small acinar proliferation in African American men. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B67.