IGF1 and Familial prostate cancer: Prostate cancer is the most common male cancer in industrialised countries, yet there are no established, potentially modifiable risk factors for prevention.1 The nutritionally regulated IGFs, and their modulating binding proteins (IGFBPs) play a key role in somatic growth, and activate carcinogenic intracellular signalling networks.1 Meta‐analyses of epidemiological studies generally observe positive associations of circulating IGF‐I with prostate cancer,2, 3, 4 but substantial differences exist between studies.5, 6