Acromegaly and colorectal cancer

Several studies have suggested increased risk of colon cancer and polyps. Prospective studies using colonoscopy showed a three times higher prevalence of intestinal polyps and up to four times increased presence of colorectal cancer (CRC) in acromegaly than in normal controls, independently of sex, age, duration of disease and clinical status of the patients. Guidelines recommend early colonoscopic screening starting at the time of diagnosis. Interval colonic surveillance depends on the findings from the baseline colonoscopy and on insulin-like growth factor 1 (IGF-1) levels. The mechanisms involved in cancer initiation and progression in acromegalic patients remain unclear. Several hypotheses have been investigated and they may be related to sustained increase of growth hormone (GH) and IGF-1 levels, metabolic disorders, and genetic factors.