4th Exam Parathyroid Pathology Flashcards Preview

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Flashcards in 4th Exam Parathyroid Pathology Deck (64)
1

Inferior parathyroid glands arise from:

3rd pharyngeal pouch

2

Superior parathyroid glands arise from:

4th pouch

3

all 4 glands are most commonly found here:

on posterior thyroid surface

4

Where are migration variants more common?

inferior parathyroid glands

5

Superior variants:

Retropharyngeal, Retrolaryngeal, Retroesophageal, Mediastinum

6

Inferior variants:

Mediastinum, Aortopulmonary window, Jugularcarotid axis, Trachoesophageal groove

7

normal range in mg per gland:

< 60 mg per gland, usually 2040mg

8

3 cell types of parathyroid:

chief cells, clear cells, oxyphil cells

9

Chief cells:

Principal cells, Fried egg, Synthesize PTH

10

Clear cells:

Larger than chief cells, more cytoplasm, secrete PTH

11

Oxiphil cells:

appear after puberty, inc w age, function not clear

12

What happens when inc Ca2+ is sensed in the parathyroid?

PTH released, effects on bone and kidney

13

parathyroid is responsible for homeostasis of:

serum Ca2+ phosphorus

14

Dec serum Ca2+ effects via parathyroid:

stimulates PTH to inc serum Ca2+, negative feedback loop to dec PTH

15

Parathyroid Hormone is aka:

Parathormone

16

PTH antagonist:

calcitonin

17

Calcitonin is secreted by:

thyroid parafollicular cells, aka C cells

18

How does PTH increases serum Ca2+?

Bone: stimulates osteoclasts via RNAK, Kidney: activates vit D which inc GI uptake of Ca, which inhibit phosphate resporption

19

Increased serum Ca:

feedback inhibition PTH secretion

20

Increased Vitamin D:

feedback inhibition PTH synthesis

21

These affect (PTH levels)? renal phosphate resorption:

PTH decreases renal phosphorus resorption, Vitamin D increases renal phosphorus resorption

22

Secreted by osteocytes in response to hyperphosphatemia:

FGF-23

23

Function of FGF-23:

Increases phosphaturia (phosphate loss in urine) and inhibits 1-a hydroxylase, decreasing Vit D

24

Case: 62, woman, fatigue, dec energy, weakness, sleeping less, depressed, no hx of cancer or smoking, mild inc BP, no breast or LN masses, no fecal occult blood, Ca+ 11.5 mg/dl, BUN & creatinine normal, “Two-site” assay for PTH: increased (C-terminal, amino terminal), generalized dec bone density, radionuclide sestamibi scan – uptake w “hot spot”, lower L neck, Surgery – L inferior parathyroid gland enlarged, others normal

Hyperparathyroidism, parathyroid adenoma

25

Causes of hypercalcemia:

Malignancy, lithium, estrogens, progesterone, Vit D overload, Sarcoidosis, hyperparathyroidism, Alkali syndrome (Ca2+ carbonate supplements, alkaline antacids, sodium bicarbonate), Paget’s disease of Bone

26

Primary Hyperparathyroidism:

Parathyroid Adenoma

27

Who are more effected by Parathyroid Adenoma, men or women?

women, 3:1

28

Parathyroid Adenoma:

50-60yo, 80-85%: adenoma, 15-20%: hyperplasia (2+ glands enlarged)

29

2 preop tests for Parathyroid Adenoma:

PTH assay and sestamibi scan

30

Sestamibi scan:

@15 min: see all 4 glands, washes out at 2 hours, @2 hours: uptake persists in (metabolically active parathyroid cells of) hyperplasia

31

Intraop test for Parathyroid Adenoma:

PTH assay

32

Adenoma is easily confused w:

hyperplasia

33

How to distinguish between adenoma and primary hyperparathyroidism:

If a section goes thru hilum, might see normal parathyroid tissue, different from the lesion

34

Parathyroid adenoma is histology nonspecific, except if taken here:

exactly at hilum

35

TF? There is an inc in intraglandular fat w parathyroid adenoma.

F. dec

36

TF? Capsule compressing adjacent tissue causes adenoma.

does not make an adenoma

37

Are atypical cells predictive of malignancy?

No

38

Parathyroid Adenoma is what type of adenoma?

Clear cell adenoma

39

Primary hyperparathyroidism cancers, most to least prevalence:

adenoma, hyperplasia, carcinoma

40

Dec chief cell receptors Ca2+ ion sensing:

Primary hyperplasia

41

# of glands enlarged in parathyroid hyperplasia:

2+

42

Most common gastrinoma:

Pancreatic islet cell tumors

43

Most common prolactinoma:

Pituitary adenoma

44

MEN I PPP is aka:

Wermer’s Syndrome

45

MEN I PPP:

part of group of disorders, the Multiple Endocrine Neoplasias, affect endocrine system thru development of neoplastic lesions in pituitary, parathyroid gland and pancreas, loss of MEN 1 suppressor gene, Chr 11q11-13, Parathyroid hyperplasia, pancreatic islet cell tumors (most common gastrinoma), pituitary adenomas (most common prolactinoma), adrenal adenomas less common

46

MEN II PPT:

Parathyroid hyperplasia, Pheochromocytoma, Thyroid medullary carcinoma

47

Secondary Hyperparathyroidism:

Usually chronic renal failure, Inadequate production of active Vit D, red GI absorption of Ca2+, renal retention of phosphate, inc serum phosphate depresses serum Ca2+, compensatory increased PTH, parathyroid hyperplasia, Serum Ca++ usually low normal or low, bone lesions, Histo: fibrosis, hemorrhage, hypertrabecular pattern

48

Tertiary Hyperparathyroidism:

Occurs in setting of longstanding secondary hyperplasia, autonomous hyperplasia develops, monoclonal population in one focus, hypercalcemia, Rx: surgery to remove 3+ glands

49

Least common primary hyperparathyroidism:

Parathyroid Carcinoma

50

Parathyroid Carcinoma:

30-60yo, palpable mass, PTH > 3x normal, profound symptomatic hypercalcemia, may be assoc w prior neck irradiation or hyperparathyroid jaw tumor syndrome, autosomal dominant, mutation HRPT2, central benign fibro-osseus tumors

51

Diagnostic criteria for parathyroid carcinoma:

Invasion into surrounding organs, lymphatic or vascular invasion, cytologic pleomorphism and mitotic activity may not be predictive

52

Hyperparathyroidism is assoc w (pneumonic):

Stones, Bones, Moans, Groans

53

Stone issues related to hyperparathyroidism:

Kidney stones

54

Bone issues related to hyperparathyroidism:

Osteoporosis, fractures, brown tumors

55

Moans related to hyperparathyroidism:

Depression

56

Groans issues related to hyperparathyroidism

GI tract problems

57

Case: 30yo, painful mass in lower L jaw, lethargic, began months ago w slight swelling, inc along w lethargy, swelling - firm to touch, Xray: multilocular radiolucency, incisal biopsy done, histo path showed chronic inflammatory cells w many multi-nucleated giant cells, hemorrhagic areas and hemosiderin, serum Ca2+: 14 mg/dl, PTH: 890 pg/ml

Mandibular tumor?

58

Mandibular Tumor:

Bone production (membranous, immature bone), not a giant cell tumor, but a giant cell process, brown tumor, loss of lamina dura, root resorption of teeth, complication of hyperparathyroidism

59

Bone Tumor:

Circumscribed lytic lesion, hemorrhage, increased vascularity, hemosiderin: brown, inc osteoclastic activity, macs, reparative fibrous tissue, sometimes cystic

60

Dental Consequences of Hyperparathyroidism

Bone disease, brown tumor, dec bone density, weak teeth, soft tissue calcifications, loss of lamina dura, widening of PDL, resorption of tooth roots

61

Generalized hyperparathyroidism:

Hands: subperiosteal bone resorption, very advanced stage… doesn’t progress this far today due to Ca2+ testing

62

Paget’s Disease of Bone:

Disordered bone remodeling, cotton wool appearance, disorganized thickening

63

Tumor Induced Rickets:

Osteogenic osteomalacia (softening of bone), FGF-23 induced phosphaturia, FGF-23 can be secreted by a variety of bone and soft tissue tumors, widespread bony lytic lesions, serum PTH, Ca, P normal, inc P and Ca in urine

64

Hypercalcemia in cancer:

Paraneoplastic syndrome, squamous ca (lung, esophagus), renal cell ca, serum PTH is low, often secrete PTHrP (related protein), shares 1st 13 AA of PTH, binds to PTH receptors, bone mets, osteoclast activating factors secreted by tumor