A Rare Entity: TSH-Secreting Adenoma
TSH-secreting adenomas are rare but must be considered in the differential diagnosis of inappropriately normal to elevated TSH in the presence of elevated free serum thyroid hormone levels (FT4, FT3), which is termed central hyperthyroidism. The diagnosis of TSH-secreting adenoma in a patient with central hyperthyroidism is usually made based on clinical and family history, α-subunit testing, SHBG levels, and pituitary MRI after ruling out other thyroid-related conditions as discussed in this chapter. A full pituitary hormone evaluation must be completed upon diagnosis of a TSH-secreting adenoma, and neuroophthomology evaluation should be obtained in the presence of a macroadenoma with concern for contact with the optic nerve or chiasm. Therapeutic options for patients with TSH-secreting adenomas include transsphenoidal pituitary surgery, medical treatment with somatostatin analogs (SSAs), radiation therapy, or a combination of these modalities. Regardless of treatment, these patients should have long-term endocrine follow-up with continued biochemical and radiologic surveillance.
KeywordsMacroadenoma Pituitary adenoma Sellar mass Central hyperthyroidism Thyrotropinomas TSH-secreting pituitary adenoma Somatostatin analogs
- 12.Brucker-Davis F, Oldfield EH, Skarulis MC, Doppman JL, Weintraub BD. Thyrotropin-secreting pituitary tumors: diagnostic criteria, thyroid hormone sensitivity, and treatment outcome in 25 patients followed at the National Institutes of Health. J Clin Endocrinol Metab. 1999;84:476–86.CrossRefPubMedGoogle Scholar
- 21.Beck-Peccoz P, Persani L, Lania A. Thyrotropin-secreting pituitary adenomas. In: De Groot LJ, Chrousos G, Dungan K, et al., editors. Endotext. South Dartmouth, MA: MDText.com, Inc.; 2000.Google Scholar