Tirotoksikozun Nadir Bir Nedeni: TSH Salgılayan Hipofiz Adenomu

Öz

Tiroid stimulan hormon (TSH) salgılayan hipofiz adenomu (TSHoma) tirotoksikozun nadir görülen sebeplerinden biridir. Tanı genellikle uygunsuz TSH yüksekliğinin araştırılması ya da hipofizer insidentalomanın tetkiki sırasında konulmaktadır. Olgumuz bilinen poliskistik over sendromu olan 26 yaşında kadın hasta olup altı aydır olan titreme, terleme ve baş ağrısı yakınmalarıyla kliniğimize başvurdu. Laboratuvar analizlerinde serum serbest T3 ve T4 düzeyi yüksek iken TSH düzeyi normal sınırlarda saptandı. Seks hormonu bağlayıcı globülin (SHBG) düzeyi normal sınırlardaydı Manyetik rezonans görüntüleme sonucunda hipofiz bezinde makradenom izlendi. TRH uyarı testine TSH yanıtı saptanmadı. TSHoma tanısı alan hastada preoperatif oktreotid ve metimazol tedavisi ile ötiroidizm sağlandıktan sonra hipofiz cerrahisi uygulandı. Cerrahi materyalin histopatolojik incelemesinde fibrotik değişikliklerle birlikte prolaktin ile pozitif, TSH ile negatif boyanma izlendi. Bu olgu sunumunda SHBG düzeyi normal ve TSH boyaması negatif olmasına rağmen uygunsuz TSH salınımı nedeniyle TSHoma tanısı alan bir hastayı sunmayı amaçladık.

Anahtar Kelimeler

• Tiroid stimulan hormon salgılayan hipofizer adenom
• tirotoksikoz
• hipertiroidi
• oktreotid

A Rare Cause of Thyrotoxicosis: TSH-Secreting Pituitary Adenoma

Öz

Thyroid-stimulating hormone (TSH) secreting pituitary adenoma (TSHoma) is one of the rare causes of thyrotoxicosis. The diagnosis is usually made during investigating inappropriate TSH elevation or pituitary incidentaloma. Our patient, a 26-year-old female patient, known to have polycystic ovary syndrome, was admitted to our clinic with complaints of tremor, sweating, and headache for six months. Laboratory analysis showed serum free T3 and T4 levels were elevated, while TSH levels were within normal limits. Sex hormone binding globulin (SHBG) level was within normal limits. Macroadenoma was observed in the pituitary gland at magnetic resonance imaging. TSH secretion did not increase much in response to the thyrotropin-releasing hormone. The patient was diagnosed with TSHoma, and pituitary surgery was performed after euthyroidism was achieved with preoperative octreotide and methimazole treatment. Positive staining with prolactin and negative staining with TSH were observed along with fibrotic changes in the histopathological examination of the surgical material. We aimed to present a patient diagnosed with TSHoma due to inappropriate TSH secretion, although her SHBG level was normal and TSH staining was negative in the current case report.

Anahtar Kelimeler

• Thyroid stimulating hormone secreting pituitary adenoma
• thyrotoxicosis
• hyperthyroidism
• octreotide

Kaynakça

1. 1. Beck-Peccoz P, Lania A, Beckers A, Chatterjee K, Wemeau J-L. 2013 European thyroid association guidelines for the diagnosis and treatment of thyrotropin-secreting pituitary tumors. Eur Thyroid J 2013;2(2):76–82.
2. 2. Tjörnstrand A, Nyström HF. DIAGNOSIS OF ENDOCRINE DISEASE: Diagnostic approach to TSH-producing pituitary adenoma. Eur J Endocrinol 2017;177(4):R183–97.
3. 3. Beck-Peccoz P, Persani L, Lania A. Thyrotropin-Secreting Pituitary Adenomas [Internet]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext. South Dartmouth (MA): MDText.com, Inc.; 2000 [cited 2022 Aug 7]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK278978/
4. 4. Pellegrini I, Barlier A, Gunz G, et al. Pit-1 gene expression in the human pituitary and pituitary adenomas. J Clin Endocrinol Metab 1994;79(1):189–96.
5. 5. Ando S, Sarlis NJ, Oldfield EH, Yen PM. Somatic mutation of TRbeta can cause a defect in negative regulation of TSH in a TSH-secreting pituitary tumor. J Clin Endocrinol Metab 2001;86(11):5572–6.
6. 6. Beck-Peccoz P, Brucker-Davis F, Persani L, Smallridge RC, Weintraub BD. Thyrotropin-secreting pituitary tumors. Endocr Rev 1996;17(6):610–38.
7. 7. Yamada S, Fukuhara N, Horiguchi K, et al. Clinicopathological characteristics and therapeutic outcomes in thyrotropin-secreting pituitary adenomas: a single-center study of 90 cases. J Neurosurg 2014;121(6):1462–73.
8. 8. Beck-Peccoz P, Persani L, Mannavola D, Campi I. Pituitary tumours: TSH-secreting adenomas. Best Pract Res Clin Endocrinol Metab 2009;23(5):597–606.

9. 9. Perticone F, Pigliaru F, Mariotti S, et al. Is the incidence of differentiated thyroid cancer increased in patients with thyrotropin-secreting adenomas? Report of three cases from a large consecutive series. Thyroid 2015;25(4):417–24.
10. 10. Socin H, Chanson P, Delemer B, et al. The changing spectrum of TSH-secreting pituitary adenomas: diagnosis and management in 43 patients. Eur J Endocrinol 2003;148(4):433–42.
11. 11. Beck-Peccoz P, Roncoroni R, Mariotti S, et al. Sex Hormone-Binding Globulin Measurement in Patients with Inappropriate Secretion of Thyrotropin (IST): Evidence against Selective Pituitary Thyroid Hormone Resistance in Nonneoplastic IST*. The Journal of Clinical Endocrinology & Metabolism 1990;71(1):19–25.
12. 12. Saddick SY. Identifying genes associated with the development of human polycystic ovary syndrome. Saudi Journal of Biological Sciences 2020;27(5):1271–9.
13. 13. Xing C, Zhang J, Zhao H, He B. Effect of Sex Hormone-Binding Globulin on Polycystic Ovary Syndrome: Mechanisms, Manifestations, Genetics, and Treatment. IJWH 2022;Volume 14:91–105.
14. 14. Fang H-J, Fu Y, Wu H-W, et al. Short-term Preoperative Octreotide for Thyrotropin-secreting Pituitary Adenoma. Chinese Medical Journal 2017;130(8):936–42.
15. 15. Fukuhara N, Horiguchi K, Nishioka H, et al. Short-term preoperative octreotide treatment for TSH-secreting pituitary adenoma. Endocr J 2015;62(1):21–7.
16. 16. Wallace IR, Healy E, Cooke RS, Ellis PK, Harper R, Hunter SJ. TSH-secreting pituitary adenoma: benefits of pre-operative octreotide. Endocrinol Diabetes Metab Case Rep 2015;2015:150007.
17. 17. Yang C, Wu H, Wang J, et al. Successful management of octreotide-insensitive thyrotropin-secreting pituitary adenoma with bromocriptine and surgery: A case report and literature review. Medicine 2017;96(36):e8017.
18. 18. Ng R, Kellen JA, Wong AC. Plasminogen activators as markers of tumor colonization potential. Invasion Metastasis 1983;3(4):243–8.
19. 19. Yoon JH, Choi W, Park JY, et al. A challenging TSH/GH co-secreting pituitary adenoma with concomitant thyroid cancer; a case report and literature review. BMC Endocr Disord 2021;21(1):177.