Abstract:
The era of screening for prostate cancer (PCa) using serum prostate specific antigen (PSA) has led to an
increase in the detection of low-grade prostate cancers that pose little risk of either metastatic spread or death.
Additionally, these men may be now exposed to morbidities of over treatment with little or no benefit of
cancer-specific survival. Active surveillance (AS) has thus evolved as a recommended management strategy for
men with low grade disease, providing the benefit of an individualized approach of carefully monitoring
disease progression, sufficient to permit timely therapeutic intervention. However, concerns about under-
grading, variations in criteria for AS eligibility, patient reported anxiety, depression, doubts about the possible
progression of the disease as well as higher decisional conflict regarding selection of AS, men on AS have been
reported to ultimately opt for treatment without any major change in tumor characteristics. On the other hand,
men on AS are a subgroup, who are highly motivated and eager to make positive lifestyle
changes to further reduce their risk of PCa progression- providing an opportunity for
chemoprevention. Chemoprevention strategies with 5-alpha-reductase inhibitors significantly reduced the
risk of prostate cancer progression. However their use was also associated with increased detection of high-
grade disease, severely limiting their clinical adoption. Currently, there is a paucity of research that
systematically examines agents for chemoprevention in men on AS. Green tea catechins (GTC)
influence several hallmarks of carcinogenesis, including prostate carcinogenesis, with an acceptable safety
profile, making them attractive candidates for PCa chemoprevention. Several epidemiological, in vitro,
preclinical and early phase trials completed by our team and others have shown that the GTC are potent
inhibitors of PCa carcinogenesis through multiple mechanisms, bioavailable in tissue and plasma, reduces
several intermediate biomarkers implicated in PCa progression and without toxicities at these doses. Based on
the available evidence, we hypothesize that men with biopsy proven adenocarcinoma of the prostate who
meet the criteria for AS, who receive GTC at a dose of 800 mg EGCG per day (vs. placebo) for 24 months, will
have a significantly decreased rate of clinical progression. We will test this hypothesis using a rigorous
experimental design in a phase II, randomized clinical trial to evaluate the safety, effectiveness and
potential mechanism by which GTC modulates clinical progression and the related biological biomarkers
relevant to PCa progression in men on AS for PCa. Positive results from this study will be critical
to inform development a phase III clinical trial and ultimately provide a strategy for secondary chemoprevention
in men on AS, for whom, currently, there are no options for reducing risk of progression to PCa.