Pituitary Pathology- Hunt Flashcards
What hormones are released from the anterior pituitary?
What hormones are released from the hypothalamus that control their release?
- FSH (stimulated by GnRH)
- LH (stimulated by GnRH)
- ACTH (stimulated by CRH)
- TSH (stimulated by TRH)
- Prolactin (inhibited by dopamine)
- GH (stimulated by GHRH, inhibited by somatostatin)
What hormones does the posterior pituitary release?
ADH
Oxytocin
How do the anterior and posterior pituitary differ on histology?
Anterior pituitary generally stains darker on the gross specimen, and has a wider range of staining. It is also more ‘clumped’ and less homogenous.
This makes sense because the anterior pituitary secretes a wider variety of products.
What is the structure of the anterior pituitary gland?
What stain shows this architecture?
The anterior pituitary is organized into clusters of cells.
The reticulin stain shows the cell clusters.
When are pituitary adenomas most likely to appear?
What are they most likely to secrete?
3rd-6th decade of life
Prolactin is most likely
non-secretory is next most likely
How would a prolactin secreting pituitary adenoma appear on histology?
How would you treat it?
Tumor would look homogenous, stain very pink (eosinphil), and have no reticular network surrounding the cell. (obviously it is homogenous for immunostains as well)
Trans-sphenoid resection
What is Sheehan Syndrome?
What causes it?
Postpartum ischemic necrosis of the pituitary
During pregnancy, the pituitary grows (inreased lactotrophs) and needs more blood to support it. If a large blood loss occurs during delivery, the ANTERIOR pituitary is damaged, resulting in hypopituitarism.
What is the stalk effect?
What impact does it have?
The stalk effect is the compression of the pituitary stalk (usually by a tumor or lesion) that decreases neuronal signalling to the pituitary.
Results in SLIGHTLY elevated prolactin levels
Rathke Cleft Cyst
Where are they found?
What causes them?
Rathke cleft cysts are found in the sella or above the sella on the pituitary gland.
They are a remant of Rathke’s cleft pough
Rathke Cleft Cyst
What problems might a RCC cause?
How does it appear on histology?
It could be asymptomatic, but possible symptoms are visual disturbances, or anterior pituitary disturbances
Columnar/cuboidal cells with cilia and possibly mucin
Craniopharyngioma
Where are they found?
What age do they occur?
Craniopharyngiomas may be found in the sella, above the sella, in the third ventricle, or in the pineal region.
Adamantinomatous type affects children >14
Papillary type affects adults 65-75
What problems might a craniopharyngioma present with?
What tissue does a craniopharyngioma grow from?
visual abnormalities & hypopituitarism
Tooth epithelium (adamantinous type) or remains of Rathke’s pouch
Are craniopharyngiomas malignant or benign?
What does an adamantinomatous type look like on histology?
What does a papillary type look like on histology?
Benign (and slow-growing)
Adamantinomatous type has dark brown fluid and cholesterol crystals with keratin and squamous epithelium
Papillary type has a papillary structure and no keratin…. (all it says)
