Which hormone used to be called prolactin inhibiting factor?
Dopamine
TSH, PRL, ACTH, GH, FH, LH are released by
Anterior pituitary
TRH, PIF, CRH, GHRH, GIH, GnRH are released by
hypothalamus
Pink staining acidophils of pituitary secrete which hormones
GH, PRL
Dark purple staining basophils of pituitary secrete which hormones
ACTH, TSH, FSH, LH
Where are ADH and oxytocin made, and also where are they later released from?
Made in hypothalamus, released by posterior pituitary
This part of the pituitary resembles neural tissue with intra-axonal neurosecretory granules
posterior pituitary
Another name for ADH
vasopresin
MC cause of hyperpituitarism
Anterior lobe adenoma
How do we classify pituitary adenomas?
functional vs non-functional
Expanding pituitary lesions can compress what nerve structure, leading to what symptom?
Optic chiasm - bitemporal hemianopsia
MC pituitary tumor
Pituitary adenoma
MC tumor of brain
Pituitary adenoma
How do you differentiate a macro- from micro-adenoma?
> 10mm = macroadenoma.
Silent and hormone negative adenomas are more likely to be macro or micro when found?
Macro - lack endocrine abnormalities that would alert patient
Non-functioning tumors may also be referred to as this (relates to how it reacts to staining)
chromophobic
Usually just one cell line increases in pituitary adenoma. What is the MC subset of a pit. adenoma? (it is also the MC functioning and MC cause of endocrine problems)
Prolactinoma
T/F - a typical pituitary adenoma is soft, well-circumscribed and confined to the sella turcica
T
Microscopy reveals small round cells with uniformly round nuclei and pink to blue cytoplasm. Cells arranged in nests or cords and with prominent vascularity
pituitary adenoma
This tumor’s presenting sxs usually are limited to HA, visual field defects, cranial nerve deficits, possibly hypopituitarism
Non-functioning pituitary adenoma
T/F prolactinomas tend to be weakly acidophilic or chromophobic (sparsely granulated)
T
Are men more likely to have a micro or macro adenoma?
macro - their sx picture is nonspecific - low libido
Pituitary adenomas are associated with which MEN syndrome?
MEN 1
this MEN syndrome has parathyroid adenomas, entero-pancreatic tumors, pituitary adenomas
MEN1
MEN syndrome with parathyroid adenomas, medullary thyroid carcinoma, pheochromocytoma
MEN2A
MEN syndrome with medullary thyroid carcinoma, pheochromocytoma, mucosal neuromas, marfanoid body habitus
MEN2B
MC initial sx of pituitary apoplexy
sudden HA w/ rapidly worsening visual field defect
Name for postpartum hypopituitarism
Sheehan’s syndrome
What is taking up space in empty sella syndrome
CSF
MC implicated lesions in hypothalamic suprasellar tumors
Gliomas and craniopharyngiomas
Craniopharyngioma is derived from the vestigial remnants of _______
Rathke’s pouch
2nd MC functioning pituitary adenoma
Excess GH - acromegaly/gigantism
Are craniopharyngiomas functioning? and are they dangerous?
Non-functioning, benign but can kill via space-occupying effect
This tumor is made of epithelial cells and has palisading cells, as well as a smooth noncellular area of lamellar “wet” keratin
craniopharyngioma
MC extracerebral CA’s to metastasize to the pituitary
Breast, Lung
Thyroid hormone receptors preferentially bind T3 or T4?
T3 - giving it greater biological activity than T4
These thyroid cells secrete calcitonin
“C” cells (parafollicular cells) - found in the interstitial between the follicles or adjacent to the cuboidal epithelium
MC cause of Hypothyroidism
Hashimoto’s thyroiditis (autoimmune lymphocytic thyroiditis)
This thyroid dz is associated with hemochromatosis, amyloidosis
Infiltrative thyroid dz
When and with whom is death more common with hypothyroidism?
Winter, elderly
MC cause goiters worldwide
MC cause in the USA
Iodine deficiency
Graves disease
Name for accidental ingestion of excess thyroid hormone leading to hyperthyroidism
Thyrotoxicosis factitia
What does toxic vs non-toxic thyroid nodule signify
Toxic = making more of the hormone, nontoxic = not making it
MC cause lymphocytic AI thyroid dz
Hashimoto’s
Enlargement of the thyroid in Hashimotos is due to what?
Lymphocytic infiltration & fibrosis, but not tissue hypertrophy
These Ab’s are responsible for hashimoto’s
TPO (thyroid peroxidase), thyroglobulin
Grossly. the thyroid has a solid fleshy appearance with a lobular pattern. Scattered tiny nodules of darker tan colored glassy material - residual colloid.
Hashimoto’s
This cell appears in thyroid tissue of pt’s with Hashimoto’s as well as follicular thyroid CA. They stain pink with abundant eosinophilic cytoplasm as result of altered mitochondria
Hürthle cell
What can cause either hyper- or hypothyroidism?
Subacute thyroiditis
What viruses are associated with De Quervain’s thyroiditis (a type of subacute thyroiditis)?
Coxsackie virus
Adenovirus
The underlying cause of most cases of sub-acute thyroiditis
Viral
Multi-nucleated giant cells within the colloid of thyroid follicles are a distinguishing feature of _____
de Quervain’s
MC location for a thyroglossal cyst
between isthmus of thyroid and hyoid bone
MC congenital neck malformation
thyroglossal duct cyst
Most thyroid CA are of what two types?
Well-differentiated papillary or follicular tumors. Excellent prognosis
Follicles irregularly enlarged and surrounded with flattened epithelium, consistent with a lack of thyroid activity
Non-toxic multinodular goiter
This dz has a thyroid gland with autonomously functioning thyroid nodules, resulting in hyperthyroidism
Toxic Nodular Goiter or Plummer’s Dz
Biopsy shows marked hypercellularity, consistent with hyperfunctioning
Toxic thyroid nodule/nodular goiter/plummer’s
Graves dz is caused by these autoantibodies which do what?
long acting thyroid autoantibodies (LATS-Ab), activate TSH receptors
MC cause hyperthyroidism & severe hyperthyroidism
Grave’s dz
Hyperplastic epithelium with prominent infolding. Tall columnar epithelium line the unfolds. Clear vacuoles next to the epithelium from localized depletion of colloid.
Grave’s dz
Colloid cysts appear as what on a thyroid scan, helping differentiate from CA
cold nodules
T/F - it is difficult to tell a follicular adenoma from a well-differentiated carcinoma
T
Four main types of thyroid CA
Papillary
Follicular
Medullary
Undifferentiated/Anaplastic (least common)
T/F most thyroid CA are well responsive to tx
T
MC thyroid CA
Papillary carcinoma
Papillary CA is more frequently diagnosed in which age group? When is it more malignant?
Mostly in young, but worse if in elderly
Thyroid CA’s more common in hx of radiation
Papillary carcinoma, Follicular carcinoma
Gross appearance shows multifocal neoplasm because of propensity to invade lymphatics
Papillary carcinoma of thyroid
Fronds have thin fibrovascular cores and overall papillary pattern
Papillary Carcinoma
T/F-All papillary neoplasms of thyroid should be considered malignant
T
You may find a psamomma body in this thyroid cancer
Papillary carcinoma
Follicular carcinoma is MC in which age group
elderly
Gross - encapsulated and solitary and found in necrotic/hemorrhagic areas
Follicular carcinoma of thyroid
Histologically, encapsulated, well-defined follicles containing colloid
Follicular carcinoma, but follicular adenoma looks like this too, making distinguishing them difficult
This thyroid CA can be familial, transmitted as autosomal dominant and associated with MEN
Medullary carcinoma
There is a proliferation of parafollicular cells (C cells) resulting in excess serum calcitonin
Medullary carcinoma
This tumor is characterized by rapid painful enlargement of thyroid gland and most die within one year
Anaplastic carcinoma
Histology shows undifferentiated malignant cells
Anaplastic carcinoma