Endocrine 1 Flashcards
(92 cards)
1
Q
A
Normal Pituitary gland
2
Q
A
Normal Pituitary Gland
3
Q
A
Normal anterior pituitary
Red = acidophils
Purple = basophils
Clear = chromophobes
4
Q
A
Normal anterior pituitary
GH Antibody staining
5
Q
A
Normal Posterior Pituitary
6
Q
A
Pituitary Adenoma
Expansion of gland into sella turcica
7
Q
A
Pituitary Adenoma
8
Q
A
Pituitary Adenoma
9
Q
A
Pituitary Adenoma
10
Q
A
Pituitary MacroAdenoma
11
Q
A
Pituitary Adenoma
12
Q
A
Pituitary Adenoma
Monomorphic & arranged in sheets, not acini
13
Q
A
Pituitary Adenoma
Salt & Pepper chromatin
14
Q
A
Normal Thyroid
15
Q
A
Normal Thyroid
16
Q
A
Normal Thyroid
Parafollicular cells only in lateral lobes (from neural crest)
17
Q
A
Hashimoto’s Thyroiditis
“Fish-flesh” and infiltrated by lymphocytes
18
Q
A
Hashimoto’s Thyroiditis
19
Q
A
Hashimoto’s Thyroiditis
20
Q
A
Hashimoto’s Thyroiditis
21
Q
A
Hashimoto’s Thyroiditis
Lymphoid follicle with germinal center
22
Q
A
Hashimoto’s Thyroiditis
Oncocytic Herthle cells
23
Q
A
Hashimoto’s Thyroiditis
Metaplasia
24
Q
A
Thyroid Nodular hyperplasia
Due to iodine deficiency, diet, meds/genetics
25
Thyroid nodular hyperplasia
Can compress trachea or recurrent laryngeal -\> hoarse voice
26
Thyroid nodular hyperplasia
no capsule, benign
27
Grave's Disease
28
Grave's Disease
Resorption vacuoles; Hypertrophic columnar follicular cells
29
Grave's Disease
Resorption vacuoles
30
Radionuclide scan
Top left: Normal, moderate homogeneous uptake
Top right: Grave's, diffuse increased uptake
Bottom Left: Multi-nodular goiter, heterogeneous uptake
Bottom right: Thyroid neoplasm/cyst; Cold nodule
31
Papillary Carcinoma
32
Papillary Carcinoma
33
Papillary Carcinoma
Finger-like projections
34
Papillary Carcinoma
Nuclear clearing - pale "orphan annie" nuclei
Blood vessels & cuboidal tumor cells
35
Papillary Carcinoma
Nuclear groove "Coffee beans"
36
Papillary Carcinoma
Intra-nuclear pseudo-inclusions (invagination of cytoplasms)
37
Papillary Carcinoma
Calcification - Somoma body
38
Papillary Carcinoma
Calcification
39
Follicular Adenoma
40
Follicular Adenoma
Contained by fibrous capsule (top left is adenoma)
41
Follicular Adenoma
42
Follicular Adenoma
Confined by capsule, no vascular invasion
43
Follicular Carcinoma
Widely invasive
44
Follicular Carcinoma
45
Follicular Carcinoma
Capsule invasion
46
Follicular Carcinoma
47
Follicular Carcinoma
Vascular invasion
48
Left: Follicular adenoma
Middle: Follicular carcinoma
Right: Papillary carcinoma
49
Medullary Carcinoma
50
Medullary Carcinoma
51
Medullary Carcinoma
Amyloid composed of pro-calcitonin
52
Medullary Carcinoma
53
Medullary Carcinoma
54
Medullary Carcinoma
Apple-green birefringence
55
Medullary Carcinoma
Dense secretory core granules
56
Describe the anterior lobe of the pituitary gland
adenohypophysis: Origin from Rathke's pouch. Produces GH, FSH, LH, ACTH, TSH
Somatotrophs (30%) and Lactotrophs (20%) - lateral regions
Corticotrophs (15%) and thyrotrophs (10%) - central regions
Gonadotrophs (20%) - diffusely distributed
Histology: Mixed population of epithelial cells arranged in acini
Portal blood supply from hypothalamus to anterior pit.
57
Describe the posterior lobe of the pituitary gland
Neurohypophysis: origin-floor of 3rd ventricle
Releases vasopressin (ADH) and oxytocin - hormones produced in hypothalamus and travel in axons to posterior lobe)
58
What are the functional classification of pituitary adenomas?
Classification of pituitary tumors based on serum hormone levels and/or immunohistochemical staining.
10% Corticotroph adenoma - secrete ACTH and POMC -\> Cushing's syndrome
20% Somatotroph adenoma - secrete GH -\> Acromegaly, gigantism
1-3% Thyrotroph adenoma (rare) - secrete TSH -\> thyrotoxicosis, usu. asymptomatic
10-15% Gonatotroph adenoma - secrete LH, FSH, & subunits -\> usu. asymp.
25% Lactotroph adenoma (prolactinoma) most common - secrete PRL -\> galactorrhea, hypogonadism, amenorrhea, infertility, loss of libido & impotence in men
20-30% Null cell adenomas - do not secrete hormones
59
What is the gross and microscopic pathology of a pituitary adenoma?
Gross: Enlarged pituitary gland with mass effect (macroadenoma \>1cm) or circumscribed nodule within pituitary gland (micro \<1cm)
Microscopic: Disruption of normal pituitary architecture (sheets, expanded nests, trabeculae), monomorphous population of cells
60
What are some S/sx of Acromegaly?
61
What are some S/Sx of Cushing's?
62
Describe the normal thyroid gland
15-25 gm in adults, but variable
Right & left lobes connected by isthmus, may have pyramidal lobe
Follicles lined by follicular epithelial cells (cuboidal/low columnar)
Colloid (stored thyroid hormone, thyroglobulin) appears eosinophilic, acellular material
Parafollicular "C" cells located between follicles
63
What is a goiter?
Enlargement of the thyroid gland
Nodular vs. diffuse
Hyper vs. hypofunctioning
64
What is Hashimoto's thyroiditis?
Chronic lymphocytic thyroiditis
Predominantly affects women, usually middle aged-elderly
Anti-TSH receptor Ab (inhibitory), anti-thyroglobulin, anti-thyroid peroxidase Ab
Initially may be thyrotoxic, then become hypothyroid
Increased risk for malignancy, lymphoma, and possibly carcinoma
65
What is the grosss and microscopic pathology of Hashimoto's thyroiditis?
Gross: diffuse firm enlargement of thyroid, well demarcated from adjacent tissue
Microscopic: lymphocytic infiltrate with germinal centers
Oncocytic (Hurthle cell) metaplasia of follicular epithelium
Destruction of follicles, leading to fibrosis in late stages
66
S/Sx of Hashimoto's Thyroiditis
67
Pathogenesis of Hashimoto's Thyroiditis
68
Diffuse Hyperplasia
Who, Pathogenesis, Gross/Histo
Grave's Disease Classic triad: hyperthyroidism, ophthalmopathy (exophthalmos), pretibial myxedema
Who: Young women (20-40 y.o)
Pathogenesis: TSI, anti-TSH Ab, Thyroid growth-stimulating immunoglobulins
Gross: symmetric enlargement of thyroid gland
Histo: Follicular hyperplasia with papillary infoldings, tall/columnar cells, scallping of margins of colloid within follicles
69
Nodular hyperplasia
Multinodular goiter
Idiopathic, usually clinicaly euthyroid
Mutliple nodules, often with one dominant nodule
Variable appearances: large/cellular/hyperplastic nodules, hemorrhage, cystic degeneration
70
S/Sx of thyroid hyperplasia
71
Graves' vs. Hashimoto's Pathogenesis
72
Papillary thyroid carcinoma
How common is it?
Who is affect?
How does it present? (Gross/Histo)
Prognosis?
Most common type of thyroid carcinoma (75-85% of thyroid carcinoma)
Women more commonly affects, presents with cold thyroid nodule
Gross: solid/cystic, firm, fibrous, often infiltrative appearance
Histo: Papillae lined by cuboidal to columnar cells
Nuclear features characteristic (intranuclear pseudoinclusions; nuclear clearing/grooves)
Psammoma bodies (laminated calcifications)
Prognosis: 95% 10 year survival, commonly metastasize to regional lymph nodes
73
Describe Gross/Histo of Follicular adenoma
Euthyroid
Gross: Usually solitary, encapsulated nodule
Histo: Macro/micro follicular, appearance of cells differs from surroudning normal thyroid gland
Neither capsular invasion nor vascular invasion present
74
Follicular carcinoma
Who does this affect?
Gross/Histo
Metastasizes to \_\_\_
Prognosis
15-20% of thyroid carcinomas
Women predominantly affected, older age group
Gross: Widely invasive or encapsulated nodule
Histo: Widely invasive-extensive infiltration of normal thyroid or vascular invasion
"Minimally invasive"-capsuclar or vascular invasion present
Hematogenous metastasis to lungs/bones
Prognosis: Widely invasive (50% 10yr survival); minimally invasive (90% 10yr survival)
75
Medullary carcinoma
How common is it
Associations
Produces \_\_\_\_
Due to \_\_\_\_
Histo
Metastasis
5-10% of thyroid carcinomas, some associated with MEN2A/2B
Derived from parafollicular cells (neuroendocrine tumor)
Produce calcitonin (hypocalcemia uncommon)
Due to activating mutations of RET proto-oncogene (familial and some sporadic tumors)
Histo: Marked variation in appearances
Commonly has neuroendocrine appearance with nests & trabeculae of uniform cells
Amyloid within stoma common (calcitonin deposition)
Tumor cells stain from chromogranin and synaptophysin (neuroendocrine markers)
Spreads via lymphatics/blood to lymph nodes, lungs, liver, bones
76
Pathogenesis of various carcinomas
77
What drug can be given for a prolactinoma?
Bromocriptine:
Dopamine agonist that inhibits PRL secretion and shrinks lactotrophs
78
What is the stalk effect?
| (in terms of excess prolactin)
Mildly elevated PRL is a common phenomenon, related to "stalk effect" rather than direct secretion by a pituitary adenoma. Any mass in the site can interfere mechanically with hypothalamic-hypophyseal connections and disrupt the steady-state inhibitory effect of the hypothalamus on PRL secretion by the AP gland. Does not justify a diagnosis of PRL-secreting pituitary adenoma.
79
What explains visual defecits in AP adenomas?
Compression of the optic chiasm causes bitemporal loss of peripheral vision.
80
What HLA types are strongly associated with Graves disease?
HLA-B8
HLA-DR3
81
What is the most important screening test to determine functional status of the thyroid gland?
TSH assay: elevated in hypo, close to zero in hyperthroidism.
82
What form of hyperthyroidism shows exopthalmos?
Graves Disease. Only.
Treatment of graves focuses on reducing T4 secretion. This does not affect exophthalmos because it is an autoimmune problem (with TSI).
83
What causes enlargement of the thyroid gland in Hashimoto's thyroiditis?
Infiltration by lymphoid cells.
84
What HLA types are associated with Hashimoto's?
HLA-DR5
HLA-DR3
85
Patient has Hashimoto's.
Patient takes oral contraceptives.
Patient has slightly elevated total T4 (with decreased free T4).
Why?
OCPs can increase the quantitiy of binding proteins and drive up the total T4 without changing the free fraction.
86
What mutagenic agent increase the incidence of papillary thyroid carcinoma?
Radiation
87
What genetic alteration can be found in papillary thyroid carcinoma?
Rearragement of the tyrosine kinase portion of RET proto-oncogene (chromosome 10) to put the tyr kin portion under the promotor of a gene that is constitutively expressed by follicular cells. Normally, tyr kin receptor is not normally expressed by thyrocytes.
[Causes high-level expression of tyrosine kinsase portion of the receptor as an unregulated growth signal)
88
What cells give rise to medullary carcinoma of the thryoid?
C cells
89
Do medullary carcinomas arise in the thyroid isthmus or thyroglossal duct remnants?
No. C cells migrate from neural crest to lateral thyroid lobes.
90
What hormone does medullary thyroid carcinoma most commonly secrete?
Calcitonin
| (ACTH also possible)
91
Function of calcitonin?
Help lower serum calcium
92
What is the origin of amyloid in medullary thyroid carcinoma?
Excess procalcitonin deposition
