Repeated colonoscopic screening of patients with acromegaly: 15-year experience identifies those at risk of new colonic neoplasia and allows for effective screening guidelines

Abstract

Objective: It is suggested that patients with acromegaly have an increased risk of colorectal cancer and pre-malignant adenomatous polyps. However, the optimum frequency with which colonoscopic screening should be offered remains unclear. Design: To determine the optimum frequency for repeated colonoscopic surveillance of acromegalic patients. Methods: We retrospectively reviewed the case records of all patients with acromegaly seen in our centre since 1992: 254 patients had at least one surveillance colonoscopy, 156 patients had a second surveillance colonoscopy, 60 patients had a third surveillance colonoscopy and 15 patients had a fourth surveillance colonoscopy. Results: The presence of hyperplastic or adenomatous polyps was assessed in all patients, while one cancer was detected at the second surveillance. At the third surveillance, mean (GS.D.) serum IGF1 levels (ng/ml) in patients with hyperplastic polyps were significantly higher than those with normal colons (P!0.05). The presence of an adenoma rather than a normal colon at the first colonoscopy was associated with a significantly increased risk of adenoma at the second (odds ratio (OR) 4.4, 95% confidence interval (CI) 1.9-10.4) and at the third (OR 8.8, 95% CI 2.9-26.5) screens. Conversely, a normal colon at the first surveillance gave a high chance of normal findings at the second (78%) or third surveillance (78%), and a normal colon at the second colonoscopy was associated with normality at the third colonoscopy (81%). Conclusions: Repeated colonoscopic screening of patients with acromegaly demonstrated a high prevalence of new adenomatous and hyperplastic colonic polyps, dependent on both the occurrence of previous polyps and elevated IGF1 levels.

MANAGEMENT OF ENDOCRINE DISEASE: Acromegaly and cancer: an old debate revisited

“…They are also more common in men, in patients with a disease duration longer than 5 years, in those with three or more skin tags, and in cases with a family history of colonic polyps (4,11). When a polyp is found, there is around 25-41% chance of recurrence within 3 years, and the risk of new adenomas is related to the presence of polyps at the initial colonoscopy and persistently elevated GH and IGF1 levels (43). By contrast, normal initial colonoscopy combined with controlled acromegaly highly predicts a negative follow-up exam.…”

“…As previously discussed, the association between GH and IGF1 levels, the duration of the acromegaly, and the presence of malignancies, especially CRC and thyroid cancer, is still an unsolved issue. There is some evidence that persistence of posttreatment high-serum GH and IGF1 levels is associated with the appearance of new colonic adenomas, and possibly CRC, particularly in patients with a previously abnormal colonoscopy (43). It is unclear if a relationship between thyroid volume, duration of the disease and hormone levels exists (56).…”

“…By contrast, a statement from a joint conference of the Growth Hormone Research Society and the Pituitary Society, published in 2004, stated that colonoscopy should be undertaken in patients with acromegaly only at the age of 50 years, according to conventional guidelines for CRC screening (72). Other groups have claimed that initial surveillance should begin earlier in acromegaly, at the age of 40 years, for early detection of precancerous polyps (7,42,43). In the Endocrine Society guidelines, screening colonoscopy was suggested (rather than recommended) at diagnosis for all acromegaly patients, reflecting the fact that the recommendation was categorized as being weak with low quality of evidence (71).…”

“…If a polyp is detected in the first examination, there is a good agreement that a second colonoscopy has to be done in an interval of 3-5 years, depending on the number, size and histology of the resected lesion. The interval for a second exam in patients with a normal initial colonoscopy and persistently elevated GH and IGF1 levels is controversial, but 5 years seem to be a reasonable approach (42,43,73).…”

60 YEARS OF NEUROENDOCRINOLOGY: Acromegaly

“…Some only consider it at 50-55 years (Renehan et al 2001), but even younger patients harbor colonic tumors, so initial colonoscopy at ACM diagnosis has been suggested (Terzolo et al 2005). Repeated colonoscopy every 10 years in controlled ACM with a normal initial result and every 5 years in those with benign tumors or uncontrolled disease appears reasonable (Dworakowska et al 2010).…”