State of the art paper Thyroid diseases in patients with acromegaly

Abstract

Acromegaly often involves the presence of different pathologies of the thyroid gland. Long-lasting stimulation of the follicular epithelium by growth hormone (GH) and insulin-like growth factor 1 (IGF-1) can cause disorders in thyroid function, an increase in its mass and the development of goitre. Acromegalic patients present most frequently with non-toxic multinodular goitre. Nodules are more prevalent in patients with active acromegaly. It has been suggested that then thyroid size increases and it can be reduced through treatment with somatostatin analogues. The relationship between thyroid volume and the level of IGF-1 and the duration of the disease is unclear. Each acromegalic patient requires a hormonal and imaging evaluation of the thyroid when the diagnosis is made, and an accurate evaluation during further observation and treatment. Although the data concerning the co-occurrence of acromegaly and thyroid cancer still remain controversial, it is particularly important to diagnose the patient early and to rule out thyroid cancer.

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

“…Consequently, there are many examples of micropapillary carcinomas and incidentally diagnosed tumors in these series whose natural history and impact on acromegaly survival is unknown. This observation is in line with studies in the general population, suggesting that the apparent increase in thyroid cancer incidence can be attributed to a screening effect linked to the use of modern diagnostic tools, which has produced a high number of 'incidentally' discovered less aggressive thyroid tumors (55,56,57).…”

“…At first glance, it seems that thyroid cancer risk in acromegaly has increased considerably in the last decade, but this is unlikely (55,56,57). A cross-sectional analysis comparing a cohort of acromegaly patients with a matched control group usually results in overstated estimates, reflecting the underlying low incidence of the malignancy in the general population (9,28).…”

“…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). Recently, the German Acromegaly Registry, which included retrospective and prospective data collected at 57 specialized endocrine centers throughout Germany, could not find significant associations between any type of cancer, disease duration or disease activity (28).…”

The Incidence of Cancer Among Acromegaly Patients: Results From the German Acromegaly Registry

“…The estimated SIR of 3.6 in a meta-analysis (16) is above our estimate of 2.1, but within our 95% CI of 0.4 to 6.1. We point out, however, that the incidence of thyroid cancer is difficult to estimate in a population with high prevalence of thyroid conditions (29) and where an association between diagnostic/therapeutic procedures and incidence of thyroid carcinomas is expected (30,31). All three cases observed here occurred before diagnosis of acromegaly.…”

Zmiany ogniskowe w tarczycy u pacjentów z akromegalią — badanie kliniczno-kontrolne oraz aktualizacja metaanalizy

“…The main possible explanation of an increased risk of nodular goitre and thyroid cancer (TC) is the proliferative and anti-apoptotic effect of IGF-1 on thyrocytes, probably mediated through IGF-1 receptors [3,6,7]. The relative risk (RR) of developing TC among subjects diagnosed with acromegaly is calculated to be 2.5-4.3 in comparison to the general population [4,8,9].…”