A small study of 58 men with high-grade prostatic intraepithelial neoplasia taking lycopene (30 mg/day) over the same period (6 months) as this study, found no changes in serum IGF-I (P = 0.99) and IGFBP-3 (P = 0.53) levels between pretreatment and post-treatment groups (Gann et al., 2015). This evidence concerns the gene IGFBP3 and prostate intraepithelial neoplasia.