Pathology

Question 1

Hyper pituitary

Answer 1

Adenoma in ant lobe
Hyperplasia
Carcinoma
Ectopic
Hypothalamus

Question 2

Classification of pituitary adenoma

Answer 2

On the basis of hormones produced by neoplastic cells

Question 3

Somatostatin

Answer 3

Inhibits GH and TSH
Analogs are used to treat acromegaly

Question 4

Pathogenesis of pituitary adenoma

Answer 4

1- mutation in GNAS abrogates the activity of Gsa of GTPase leading to constitutive activation of Gsa , cAMP is produced continuously and unchecked cellular proliferation
2- MEN1, CDKN1B, PRKAR1A & AIP gene
3- cell cycle : CD1 overexpression, mutations TP 53, epigenetic silencing of RB gene, RAS oncogene.

Question 5

Somatotroph adenomas

Answer 5

GH +++IGF1~ overgrowth of bones n muscle
In child before epiphysis close: increase in body size, disproportionately long arms and legs.

After closure of epiphysis: growth of soft tissue, skin, viscera, bones of face.
Prognathism: lower jaw grows
Teeth separate
Sausage like fingers, ACROMEGALY
Diabetes mellitus: GH induced peripheral insulin resistance.

Question 6

Test for acromegaly

Answer 6

GH is not suppressed in response to oral load of glucose.

Question 7

Morphology of pituitary adenoma

Answer 7

May compress ,erode and extend in optic chiasm nd adjacent structure
Uniform polygonal cells arranged in sheets,cords and papillae
* cellular monomorphism and absence of reticulin in neoplastic adenomas

Atypical adenoma: TP53 mutations, high mitotic activity, aggressive,

Question 8

Genes in Marfan syndrome

Answer 8

Fibrillin 1
TGFBR in MFS Type II
ACTA2
MYTH11

Question 9

How to see if thyroid nodule is neoplastic?

Answer 9

Solitary nodules
In ver young or very old
Males
Radiation exposure history
Cold nodules that do not take up radioactive iodine

Question 10

Thyroid adenomas (painless) (cold)

Answer 10

Derived from follicular epithelium

Less common toxic adenomas that cause thyrotoxicosis
Pathogenesis =
Gain of function mutations in TSHR and GNAS
Thyroid autonomy
Over abundance of thyroid hormone = hyperthyroidism (HOT NODULE)

Question 11

Morphology of thyroid adenomas

Answer 11

Solitary
INTACT CAPSULE, well defined
Oxyphil change: bright eosinophilic granular cytoplasm
Nuclear pleomorphism,atypia and prominent nuclei

Question 12

Thyroid carcinoma pathogenesis

Answer 12

Female predominance
ionizing radiation in first 2 decades of life.

PAPILLARY: +MAP kinase pathway > rearranged tyrosine kinase RET and NTRK1 , point mutation in BRAF

FOLLICULAR: driver mutations in RAS or PI3K/AKT (GOF) , LOF mutations in PTEN, PAX8 , PPARG

ANAPLASTIC: RAS, TP53
These are derived from follicular epithelium.
MEDULLARY: arise from parafollicular C cells. In MEN 2
RET mutations in tyrosine kinase receptor

Question 13

Papillary carcinoma thyroid

Answer 13

Presents as painless mass in thyroid or neck when metastases to lymph nodes.

Poor prognosis in elderly.

Question 14

Encapsulated,Papillae with multiple layers of cuboidal epithelial cells, orphan annie eye nuclei due to dispersed chromatin, pseudo inclusions, psamomoma bodies present. What is it?

Answer 14

Papillary carcinoma of thyroid

Question 15

Presents as solitary cold nodule , no nodal metastases but to lungs,bone,liver, in a female above 40-60, resembling the follicles of normal thyroid, infiltrates thyroid parenchyma,hurthle cells are seen. No capsule, What is it?

Answer 15

Exclude capsule✅
Vascular invasion ✅
This is follicular carcinoma (not adenoma)
Widely invasive

A follicular variant of papillary carcinoma may progress to follicular carcinoma.

Question 16

Presents as bulky mass in neck age 65 with history + .
Highly anaplastic undifferentiated pleomorphic / spindle shaped cells
What is it.

Answer 16

Anaplastic carcinoma
Poor prognosis due to extensive growth and compromising neck structures.

Question 17

Neuroendocrine tumor that secretes calcitonin and other pp hormones. Patient has MEN 2. Patient is young child. He has dysphagiA / hoarseness,
Symptoms like diarrhoea due to VIP.
Elevated calcitoninlevels.

Answer 17

Medullary carcinoma

Morphology = both lobes, amyloid deposits, multicentricity , polygonal or spindle cells,calcitonin in cytoplasms,
Familial: multicentric C cell hyperplasia
Arise from focal hyperplasia

Question 18

3 causes of thyrotoxicosis

Answer 18

Graves’ disease: hyperplasia, autoimmune
Hyper functioning: multi nodular goiter
And adenoma of thyroid.

Question 19

Radioactive iodine determines etiology

Answer 19

Graves’ disease and toxic adenoma: increased uptake
Thyroditis: decreased uptake

Question 20

Causes of hypothyroidism

Answer 20

Thyroid dysgenesis
Deficiency of iodine (enlarged thyroid)
Hashimoto thyroiditis (enlarged thyroid)
Iatrogenic

Question 21

Baby presents after 18 day with impaired development of skeleton nd CNS , mental retardation, short stature, coarse facial features, protruding tongue, umbilical hernia. Diagnosis.

Answer 21

Cretinism

Question 22

Pathogenesis of myxedema

Answer 22

Decreased cardiac output: thyroid regulates Ca ATPase leades to SOB and less exercise capacity
Decreased blood flow: cool and pale skin
Decreased sympathetic activity: constipation and decreased sweating
Increase cholesterol and LDL
Accumulation of GAGs, hyaluronic acid in skin, SC nd viscera resulting in non pitting edema , broade and coarse facial features, large tongue and deep voice

Question 23

Symmetrical , diffuse painless enlargement in neck
Decreased TSH, Radioactive iodine uptake is low, initially raised T3 and T4.
Then levels fall with increase in TSH.

Answer 23

mononuclear inflammatory infiltrate, germinal centres

Hashitoxicosid: initially a hyper state due to disruption of thyroid follicles with release of thyroid hormones

#hurthle cells: abundant eosinophilic granular cytoplasm (metaplasia), many mitochondrion
#may be atrophic dur to fibrosis

Question 24

Neck pain wd swallowing
Fever,malaise, enlargement
ESR raised also leukocyte cpunt
History of respiratory infection

Answer 24

Subacute granulomatous thyroiditis , de quervain

Question 25

Pathogenesis of graves disease

Answer 25

Thyroid stimulating immunoglobulin mimics TSH : stimulates adenylyl cyclase.
Same by thyroid growth stimulating immunoglobulins.
TSH binding inhibitor immunoglobulins.

Infiltrative opthalmopathy: T cell mediated
Volume of retro orbit CT and extraocular muscles increase (fats, mononuclear cells, edema,matrix)

Question 26

Morphology of Graves’ disease

Answer 26

Diffuse hypertrophy and hyperplasia
Capsule intact
Small papillae but LACK FIBROVASCULAR CORE
Lymphoid hyperplasia

Question 27

Large neck mass, dysphagia, breathing problem, SVCsyndrome,
No dermopathy or eye changes

Answer 27

Graves disease

Thyrotoxicosis may develop due to autonomous nodules (TOXIC MULTINODULAR GOITRE)