Given that only three RCTs were included in this systematic review, and the high risk of bias in two of the three studies, there is insufficient evidence to either support, or refute, the use of lycopene for the prevention of prostate cancer. Similarly, there is no robust evidence from RCTs to identify the impact of lycopene consumption upon the incidence of prostate cancer, prostate symptoms, PSA levels or adverse events.
Lycopene as a chemopreventive agent in the treatment of high-grade prostate intraepithelial neoplasia.
Because of its long latency, slow growing nature, and high prevalence, prostate cancer is the best model for chemoprevention. High-grade prostate intraepithelial neoplasia (HGPIN) is a precursor of prostate cancer. Chemoprevention with lycopene has shown definite results in prostate cancer. We undertook a study to use lycopene as a chemopreventive agent in the treatment of HGPIN for preventing prostate cancer from developing in this vulnerable group of patients.
                A total of 40 patients with HGPIN were randomized into 2 groups: one received 4 mg lycopene twice a day for one year, and the other was periodically followed up. Total follow-up was one year.
                Our results show that lycopene can delay or prevent HGPIN from developing into occult prostate cancer, and there exists an inverse relationship between lycopene and prostate-specific antigen. Being a vegetable carotenoid, lycopene is a safe drug to be used for a longer period without any adverse reaction.
                Lycopene is an effective chemopreventive agent in the treatment of HGPIN, with no toxicity and good patient tolerance.