Pathology Flashcards
The thyroid gland develops from an invagination of what?
Pharyngeal epithelium
Where does the thyroid gland descend to and from?
From the foramen caecum of the tongue to the thyroglossal duct
What is known as when the thyroid gland fails to descend normally?
Lingual thyroid
If there is excessive descent of the thyroid, where does it end up?
Retrosternal in the mediastinum
What is the thyroid gland composed of?
Follicles
What cell type are the thyroid follicles surrounded by?
Cuboidal follicular epithelial cells
What is the area in the centre of each thyroid follicle known as?
Colloid
What does the thyroid colloid contain? What is this?
Thyroglobulin- this is the protein on which T3 and T4 are synthesised
What other cell type are found scattered among the thyroid follicles in the upper 2/3rds of the thyroid gland?
C-cells (parafollicular cells)
What do C-cells produce?
Calcitonin
What does calcitonin do?
Decrease serum calcium levels
Calcitonin is a good marker for what?
Medullary thyroid cancer
