„Cicha” ekspresja tyreotropiny (TSH) w akromegalii i klinicznie nieczynnych gruczolakach przysadki

Abstract

Introduction: The pituitary adenomas secreting thyrotropin (TSH) are considered the rarest type of hormonally active pituitary tumour. In spite of that, many cases are described in the literature. On the other hand, the observations of the co-expression of TSH with other pituitary hormones (mostly with growth hormone [GH]) and "silent" expression of TSH in clinically non-functioning pituitary adenomas (CNFPA) are rather scarce. Materials and methods: Among 93 examined pituitary adenomas, 22 of them were diagnosed as active acromegaly and 71 as clinically non-functioning pituitary adenomas (CNFPA). All of them were immunostained with antibodies against pituitary hormones, including the anti-TSH antibody. TSH-immunopositive adenomas are immunostained also to detect somatostatin receptor subtypes (SSTR 1-5). Results: TSH immunopositivity was found in 4.2% of CNFPA (3/71 tumours) and in 13.6% (3/22) cases of somatotropinomas manifesting as active acromegaly. All of the examined TSH-immunopositive adenomas expressed SSTR subtypes except SSTR4. The symptoms of hyperthyroidism were not observed in any of the acromegalic patients co-expressing TSH with GH. Conclusions: Our data confirm the relative rarity of TSH expression or co-expression of TSH in pituitary tumours. In most cases TSH is co-expressed with GH in patients with acromegaly and is not accompanied by hyperthyroidism. The "silent" expression of TSH may occur also, although rarely in CNFPA. The strong expression of SSTR in TSH-immunopositive CNFPA ("silent thyrotropinoma") indicates the possibility of the treatment of these tumours with somatostatin analogues. (Endokrynol Pol 2016; 67 (5): 515-518)

TSH-Secreting Pituitary Tumors: A Case Series and Literature Review

“…Immunohistochemistry is performed for diagnosis, evaluating TSH expression or coexpression of TSH in pituitary tumors. In most cases, TSH is coexpressed with growth hormone (GH) in patients with acromegaly and is not accompanied by hyperthyroidism [10,11]. Transsphenoidal endoscopic surgery (TSEM) was performed without complications.…”

Immunohistochemical detection of prolactin in clinically non-functioning pituitary adenomas

“…2020 10.5603/FHC.a2020.0014 www.journals.viamedica.pl/folia_histochemica_cytobiologica Silent corticotropinomas (corticotroph adenomas not manifested by Cushing's disease) and somatotroph adenomas without acromegaly (silent somatotropinomas) are less frequent but not exceedingly rare [1][2][3][4][5][6][7][11][12][13][14][15][16][17][18][19]. In contrast, silent thyrotropin-expressing [1][2][3][4][5][6][7]20] and prolactin-expressing pituitary adenomas are considered as very rare and the data concerning the clinical and pathological characterization of the latter of them are very scarce [5,7,21,22]. The aim of the present study is to partially fill this gap.…”