020415 thyroid pathology

Question 1

types of thyroid inflam

Answer 1

infectious thyroidits (TB)
subacute granulomatous (de Quervain) thyroiditis
chronic lymphocytic (Hashimotos) thyroiditis
fibrosing Riedel thyroiditis

Question 2

what do you see for Hashimoto thyroiditis

Answer 2

diffuse ENLARGEMENT

microscopic:
lymphocytic inflam
germinal centers
Hurthle cell change (epithelial cells with more cytoplasm and more pink due to mitochondria)

Question 3

subacute thyroiditis (de Quervain)-features?

Answer 3

granulomatous (giant cells)
suppurative (neutrophils)

pain, tenderness

Question 4

fibrous (Riedel) thyroiditis

Answer 4

due to chronic inflam
painless

microscopic:
dense fibrosis (collagen fibers)
fibrosis can extend outside of thyroid

Question 5

types of thyroid hyperplasia

Answer 5

Graves’ disease

goiter (diffuse or nodular hyperplasia)–clinical diagnosis

Question 6

Graves’ disease

Answer 6

autoimmune (diffuse involvement)

microscopic:
irregular follicles (inward folds)
scalloped colloid

Question 7

histology of goiter

Answer 7

follicles lined by crowded columnar cells
variably sized follicles
abundant colloid
initial–symmetrical, diffuse enlargement
recurrent episodes lead to multinodular gland/goiter

Question 8

FNA cannot differentiate between

Answer 8

follicular adenoma and follicular carcinoma and hyperplastic nodules

Question 9

follicular adenoma

Answer 9

benign neoplasm

most are nonfunctional
do not progress to carcinoma

microscopic:
LESS colloid
MORE cells

Question 10

macroscopic of follicular adenoma

Answer 10

completely surrounded by fibrous capsule (NO capsular or vascular invasion)

Question 11

prognosis for thyroid carcinoma

Answer 11

mortality is low

Question 12

risk factor for thyroid carcinoma

Answer 12

ionizing radiation

Question 13

types of thyroid cancers

Answer 13

papillary CA (most COMMON)
follicular CA (like follicular adenomas)
medullary CA
anaplastic CA
lymphomas
sarcomas

Question 14

RET mutation is associated with

Answer 14

medullary carcinoma of thyroid

Question 15

diagnosis of papillary carcinoma

Answer 15

NUCLEAR FEATURES ARE THE KEY:
clear nuclei-“Orphan Annie eyes”
intranuclear cytoplasmic inclusions
intranuclear grooves

Question 16

papillary carcinomas look like

Answer 16

papillary architecture (finger like projections)
dense colloid
psamomma bodies (lamellar calcifications)
multinucleated giant cells

Question 17

vascular spread to bone, lungs, liver

Answer 17

follicular thyroid carcinoma

Question 18

criteria for diagnosing follicular carcinoma

Answer 18

capsular invasion
vascular invasion

b/c follicular A has no cytologic features of malignancy. most tumors are well-differentiated. cannot differentiate from follicular adenoma unless you see invasion through capsule

Question 19

medullary carcinoma-what is it

Answer 19

neuroendocrine tumor derived from parafollicular C cells of the thyroid

20% occur within families with MEN 2 syndrome

Question 20

medullary carcinoma-micro appearance

Answer 20

nests of neuroendocrine cells
amyloid stroma (apple green birefringence)

Question 21

immunohisto for medullary carcinoma

Answer 21

calcitonin, chromogranin, synaptophysin positive

chromogranin and synpatophysin are positive b/c it’s a neuroendocrine tumor

thyroglobulin NEGATIVE

Question 22

anaplastic carcinoma

Answer 22

undifferentiated tumors of follicular epithelium

most have EXTRATHYROIDAL SPREAD OR DISTANT METASTASIS at presentation (hoarseness due to wiping out laryngeal nerves, neck pain)