In patients with acromegaly, thyroid gland is affected frequently, which results in endocrine dysfunction, structural, and neoplastic changes.[7] Total thyroid volume increases in patients with acromegaly but TSH level decreases.[4,19,20] Treatment will normalize both volume and TSH levels.[7,19,20] In addition, these changes are closely related to the IGF-1 level.[20] In our study, TSH levels were decreased and thyroid volumes were higher in patients with active disease in accordance with previous studies. The gene discussed is IGF1; the disease is acromegaly.