Clinical challenges of a co-secreting TSH/GH pituitary adenoma

Hui Yi Ng; Divya Namboodiri; Diana Learoyd; Andrew Davidson; Bernard Champion; Veronica Preda

doi:10.1530/EDM-19-0068

Clinical challenges of a co-secreting TSH/GH pituitary adenoma

Endocrinol Diabetes Metab Case Rep. 2019 Sep 17:2019:EDM190068. doi: 10.1530/EDM-19-0068. Online ahead of print.

Authors

Hui Yi Ng¹, Divya Namboodiri¹, Diana Learoyd², Andrew Davidson³, Bernard Champion¹, Veronica Preda¹

Affiliations

¹ Department of Clinical Medicine, Level 4, Macquarie University, 2 Technology Place, Macquarie University, New South Wales, Australia.
² University of Sydney, Faculty of Medicine and Health, Northern Clinical School, Reserve Road St Leonards, New South Wales, Australia.
³ Department of Neurosurgery, Level 2, Macquarie University, 2 Technology Place Macquarie University, New South Wales, Australia.

PMID: 31967973
DOI: 10.1530/EDM-19-0068

Abstract

Summary: Co-secreting thyrotropin/growth hormone (GH) pituitary adenomas are rare; their clinical presentation and long-term management are challenging. There is also a paucity of long-term data. Due to the cell of origin, these can behave as aggressive tumours. We report a case of a pituitary plurihormonal pit-1-derived macroadenoma, with overt clinical hyperthyroidism and minimal GH excess symptoms. The diagnosis was confirmed by pathology showing elevated thyroid and GH axes with failure of physiological GH suppression, elevated pituitary glycoprotein hormone alpha subunit (αGSU) and macroadenoma on imaging. Pre-operatively the patient was rendered euthyroid with carbimazole and underwent successful transphenoidal adenomectomy (TSA) with surgical cure. Histopathology displayed an elevated Ki-67 of 5.2%, necessitating long-term follow-up.

Learning points: Thyrotropinomas are rare and likely under-diagnosed due to under-recognition of secondary hyperthyroidism. Thyrotropinomas and other plurihormonal pit-1-derived adenomas are more aggressive adenomas according to WHO guidelines. Co-secretion occurs in 30% of thyrotropinomas, requiring diligent investigation and long-term follow-up of complications.

Keywords: 2019; Acromegaly; Adult; Angiography; Anxiety; Aspirin; Australia; BMI; Beta-blockers; Blood pressure; Bone mineral density; Carbimazole; DEXA scan; Dizziness; Echocardiogram; FT3; FT4; GH; GH suppression; Goitre; Goitre (multinodular); Haematoxylin and eosin staining; Headache; Heart rate; Heat intolerance; Histopathology; Hypertension; Hyperthyroidism; Hypogonadism; IGF1; Immunostaining; Insomnia; MRI; Male; Metoprolol; Osteopenia; Palpitations; Pituitary; Pituitary adenoma; Pituitary function; Plurihormonal pituitary adenoma; Prolactin; Resection of tumour; SHBG; September; Sex hormone binding globulin; Statins; Surgery; TRH stimulation; TSH; Tachycardia; Thyroid function; Thyroid ultrasonography; Thyrotrophic adenoma; Thyroxine (T4); Transsphenoidal surgery; Triiodothyronine (T3); Triiodothyronine (T3) suppression; Unique/unexpected symptoms or presentations of a disease; Ventricular hypertrophy; White.