Is there an association between acromegaly and thyroid carcinoma? A critical review of the literature

Patients with acromegaly may have higher rates of cancer, possibly due to increased plasma levels of IGF-I, which is known to promote cellular growth. While simple and multinodular goiters are more common among acromegalics, reports of thyroid carcinoma are rare, and its true incidence is unclear. Here, we review the relevant literature in the context of a case of a patient with acromegaly with persistently elevated IGF-I levels who was subsequently diagnosed with thyroid carcinoma. The incidence and potential pathophysiologic mechanisms of benign and malignant thyroid disease in acromegaly are discussed. We conclude that in acromegalic patients with persistently elevated IGF-I levels, one should ensure careful monitoring of goiter and thyroid nodules, including fine-needle aspiration of nodules that are 1 cm or larger.