Akshay Varghese, Doctor of Medicine (MD): No financial relationships to disclose
Abstract:
Background: Silent pituitary adenomas refer to adenomas that express one or more pituitary hormones or transcription factors on immunochemistry, but present as clinically non-functioning adenomas. The subset of silent thyrotroph adenomas remain rare, accounting for less than 2.4% of pituitary adenomas documented in various surgical case series, and often are clinically silent. Over 50% present with extrasellar extension and common clinical symptoms include headaches and visual disturbances.
Case: A 52-year-old female who was referred to the Pituitary Clinic in July 2021 for a new pituitary macroadenoma with a maximum dimension of 2.4cm in craniocaudal direction. There was abutment and uplifting of the optic chiasm and pre-chiasmatic optic nerve. The patient had a chronic history of non-specific neurological symptoms, including weakness, severe dizzy spells, pre-syncope, night tremors and parasthesias over the past six years. At the clinic, she had endorsed that her face had become more swollen and “moon-like” in nature, as well as water retention in her extremities. Additionally, she noted an increase in shoe size, as well as some skin, hair, and nail changes. Her hormonal panel did not show any objective evidence of overproduction or insufficiency. Given the presence of an early bitemporal visual field defect, she underwent endoscopic transsphenoidal resection in April 2023 during which the entirety of the tumour was removed. On pathology, the tumour was found to be diffusely positive for alpha subunit, Pit-1, TSH and diffuse staining with mixed perinuclear and cytoplasmic pattern for CK8/18. The Ki-67-index was < 1%. Post-operatively she had no pituitary hormone deficiency. Her vision is subjectively unchanged following surgery. She is planned for MRI in October 2023.
Discussion/
Conclusion: In our case, the silent thyrotroph pituitary adenoma was deemed to be completely resected. Other silent pituitary tumours, including silent corticotroph and silent somatotroph tumors, have a tendency for more aggressive behaviour. In the absence of good information on silent thyrotroph adenomas, we suggest it is prudent to monitor closely for early recurrence.
