Acromegaly and cancer.

In recent years, it has become increasingly recognized that acromegaly is associated with an increased prevalence of colorectal cancer and pre-malignant tubular adenomas. The aetiology of these tumours is unknown but is likely to reflect increased levels of both insulin-like growth factor I (IGF-I), which is implicated in the development of sporadic colorectal cancer, and environmental factors, such as the bile acid deoxycholic acid. There is also evidence to suggest that the prevalence of breast and perhaps haematological malignancies might be increased in acromegaly, although these associations have been based on mostly small epidemiological surveys and clarification will come in the future once large-scale epidemiological studies have been completed.