Effect of green tea catechins in patients with high-grade prostatic intraepithelial neoplasia: Results of a short-term double-blind placebo controlled phase II clinical trial

Abstract

Background and study objective: Several studies suggest a protective role of green tea catechins against prostate cancer (PCa). In order to evaluate the efficacy of green tea catechins for chemoprevention of PCa in patients with high-grade prostate intraepithelial neoplasia (HG-PIN) we performed a phase II clinical trial. Methods: Sixty volunteers with HG-PIN were enrolled to carry out a double-blind randomized placebo-controlled phase II clinical trial. Treated group took daily 600 mg of green tea catechins (Categ Plus ® ) for 1 year. Patients were screened at 6 and 12 months through prostatic biopsy and measurements of prostate-specific antigen (PSA). Results: Despite the statistically significant reduction of PSA observed in subjects who received green tea catechins for 6 and 12 months, we did not find any statistical difference in PCa incidence between the experimental groups neither after 6 nor after 12 months. However, throughout the one-year follow-up we observed very limited adverse effects induced by green tea catechins and a not significant improvement in lower urinary tract symptoms and quality of life. Conclusions: Although the small number of patients enrolled in our study and the relatively short duration of intervention, our findings seems to deny the efficacy of green tea catechins. However, results of our clinical study, mainly for its low statistical strength, suggest that the effectiveness of green tea catechins should be evaluated in both a larger cohort of men and longer trial.

Phenolic Content and Antimicrobial and Anti-Inflammatory Effects of Solidago virga-aurea, Phyllanthus niruri, Epilobium angustifolium, Peumus boldus, and Ononis spinosa Extracts

“…It is sensitive to highlight the clinical study carried out by Micali and colleagues [55], which evidenced a significant reduction in prostate-specific antigen following green tea catechin administration, thus suggesting its potential efficacy in treating/preventing inflammatory prostate diseases. Furthermore, the antiproliferative effects of green tea deriving catechins were demonstrated in multiple cancer cell lines, including prostate cancer LNCaP cells [56]. The pivotal role of catechin in the anti-inflammatory response related to extract treatment was also indicated by bioinformatics analysis (Figure 11).…”

Green tea catechins for chemoprevention of prostate cancer in patients with histologically-proven HG-PIN or ASAP. Concise review and meta-analysis

“…Four articles were finally selected for risk of bias assessment and meta-analysis (12)(13)(14)(15). Two and three of these studies were included in the metaanalyses of Cui et al (6) and Guo et al (5), respectively.…”

Dietary Factors and Supplements Influencing Prostate-Specific Antigen (PSA) Concentrations in Men with Prostate Cancer and Increased Cancer Risk: An Evidence Analysis Review Based on Randomized Controlled Trials

“…When patients with high-grade prostatic intraepithelial neoplasia (HGPIN) and/or atypical small acinar proliferation (ASAP) were recruited ( Table 5 ), daily GTCs supplementation for a year decreased serum PSA concentrations compared with placebo, in two trials [ 110 , 112 ], but failed to induce any notable change according to one RCT [ 111 ]. In trials reporting a PSA decline however, the incidence of PCa did not differ among men receiving GTCs, or placebo [ 112 ].…”