IGF1 and Familial prostate cancer: Acromegaly is an endocrine disorder (often caused by a pituitary adenoma), characterised by hypersecretion of growth hormone by the pituitary gland, generally resulting in high circulating IGF‐I concentrations.5, 6, 7 Although acromegaly has previously been implicated with an increased overall cancer incidence,8 no study has had the statistical power to robustly investigate the association between acromegaly and prostate cancer incidence or mortality.