Thyroid Pathology

Question 1

Hashimoto Thyroiditis:
which antibodies present (2)
increased possibility of which cancer? location?
Histological findings (2)
Physical findings (1)

Answer 1

1. anti-thyroid peroxidase and anti-thyroglobulin antibodies
2. INCREASED risk of NON-HODGKIN LYMPHOMA
   (B-cell marginal zone lymphoma)
3. HURTHLE cells
4. LYMPHOID AGGREGATE WITH GERMINAL CENTERS
5. moderately enlarged, non-tender thyroid. May shrink and scar if left untreated

Question 2

Subacute thyroiditis  (de Quervain)
Pathophysiology
Histology (1)
Findings (3)
Suspect if (3) which combo

Answer 2

Initially HYPERTHYROID and is self-limited
15% of cases progress to HYPOTHYROID d/t decreased TSH from initial hyperythyroid state

Histology: GRANULOMATOUS inflammation

Findings: INCREASED ESR, jaw pain, TENDER thyroid

Suspect if: young woman, recent viral illness, tender thyroid

Question 3

Riedel thyroiditis
1. pathophysiology
2. may result in (1)
3. confused with (1)
4. mediated by what? (1)
findings (4)

Answer 3

1. Thyroid replaced by fibrous tissue (hypothyroid)
2. Fibrosis may extend into local structures (airway)
3. Can be confused with anaplastic carcinoma
4. Considered a manifestation of IgG4-related systemic disease
   Findings: fixed, “rock hard” PAINLESS goiter, FEMALES

Question 4

How to NOT confuse Riedels with anaplastic carcinoma

Answer 4

Anaplastic carcinoma usually affects OLDER patients (>65)

Question 5

macrophage and eosinophil infiltrate

Answer 5

Riedel thyroiditis

Question 6

lymphocytic infiltrate

Answer 6

Hashimotos

Question 7

Granulomatous infiltrate

Answer 7

Subacute thyroiditis

Question 8

Papillary Carcinoma
how common
what do the nuclei look like
histology finding (1) and its a big one
risk changes with what (4)

fun hint from DiT

Answer 8

1. Most common (80% cases)
2. Empty nuclei (“Orphan Annie eyes”)
3. Psammoma bodies
4. INCREASED risk with RET and BRAF mutations, childhood irradiation, and tobacco

**“Psammos” means sand…Sandy was Annie’s dog

Question 9

Follicular carcinoma
*big thing that cannot come from FNA
histology (1)
metastasis

Answer 9

1. Malignant proliferation of follicles surrouded by a fibrous capsule that INVADES THYROID CAPSULE
2. Uniform follicles
3. Hematogenous metastasis

Question 10

Medullary carcinoma
precursor cells
histology finding that give it away (1)
associated with which mutation (1) and syndromes (2)
what else to look for (1)

Answer 10

1. Malignant proliferation of parafollicular “C cells” that produce calcitonin
   - -May cause hypocalcemia
2. “sheets of cells in an amyloid stroma”
3. Associated with RET mutations
4. Also part of MEN 2A and 2B syndromes
5. If diagnosis is medullary carcinoma, look for pheochromocytoma

Question 11

Undifferentiated/anaplastic carcinoma

Answer 11

1. Older patients (>65)
2. Invades local structures (dysphagia or respiratory compromise)
3. Very poor prognosis