There was some evidence of heterogeneity by study in the associations of IGF-I with aggressive disease (Phet = 0.02) (Supplementary Figure S12), and IGF-II and IGFBP-2 with overall prostate cancer risk (Phet = 0.0001 and 0.02, respectively) (Supplementary Figures S13 and S17). This evidence concerns the gene IGF2 and prostate carcinoma.