Prostate cancer (PC) is a frequent male
malignancy and represents the second most diagnosed
cancer in men. Since pre-cancerous lesions, i.e., the high-grade
prostatic intraepithelial neoplasia (HGPIN), can be detected years before progression to PC, early diagnosis and
chemoprevention are targeted strategies to reduce PC rates. Animal studies have shown that
lycopene, a
carotenoid contained in tomatoes, is a promising candidate for the
chemoprevention of PC. However, its efficacy in humans remains controversial. The present study aimed to investigate the relevance of plasma and prostate concentration of
lycopene after a
lycopene-enriched diet in patients diagnosed with HGPIN. Thirty-two patients diagnosed with HGPIN were administered a
lycopene-enriched diet (20-25 mg/day of
lycopene; through 30 g/day of triple concentrated tomato
paste) for 6 months. A 6-month follow-up prostate biopsy assessed progression to PC. Patients were classified into three groups according to the histopathological features of the 6-month follow-up biopsy results:
prostatitis; HGPIN and PC. PSA and plasma
lycopene levels were measured before and after the dietary
lycopene supplementation. Prostatic
lycopene concentration was only assessed after the supplementation diet. Only prostatic
lycopene concentration showed significant differences between the three groups (p = 0.03). Prostatic
lycopene concentration below a 1 ng/mg threshold was associated with PC at 6-month follow-up biopsy (p = 0.003). We observed no overall benefits from a 6-month
lycopene supplementation, as the rate of HGPIN progression to PC in our population (9/32, 28%) was similar to rates reported in the literature. Baseline PSA levels also showed no significant changes after a
lycopene-enriched diet. Our findings point to prostatic
lycopene concentration as a promising
biomarker of PC. Further prospective longitudinal studies are needed to assess the prognostic role of prostatic
lycopene in PC.