Pathology of the Endocrine System

Question 1

How do endocrine glands appear histologically?

Answer 1

Packets of cells
Secretory granules
Vascular
Ductless

Question 2

Where are diffuse endocrine cells found?

Answer 2

Lung
GIT
Paraganglia

Question 3

What does the posterior pituitary secrete?

Answer 3

Vasopressin

Oxytocin

Question 4

What are the hormones secreted by the anterior pituitary?

Answer 4

GH
ACTH
TSH
FSH + LH
Prolactin

Question 5

What is endocrine hyperplasia?

Answer 5

Increased number and secretory activity of cells

Question 6

What is endocrine atrophy?

Answer 6

Diminution of cells due to lack of stimulation

Question 7

What are the disease processes of endocrine organs?

Answer 7

Hyperplasia
Atrophy
Tissue damage
Neoplasia
Congenital abnormality

Question 8

What are the neoplasms found in endocrine organs?

Answer 8

Adenoma

Carcinoma

Question 9

How are causes determined in endocrine organs?

Answer 9

Morphological findings

Biochemical measurements

Question 10

What does the thyroid gland secrete?

Answer 10

T3, T4

Calcitonin

Question 11

How does the thyroid appear histologically?

Answer 11

Follicles surrounded by follicular cells

Question 12

Follicles in the thyroid contain what?

Answer 12

Colloid (thyroglobulin)

Question 13

What do C-cells secrete?

Answer 13

Calcitonin

Question 14

What happens within the epithelial cells?

Answer 14

TH synthesis
Iodination
Resorption
Release

Question 15

TRH secretion from the hypothalamus is stimulated by what?

Answer 15

Cold

Stress

Question 16

What are the causes of hyperthyroidism?

Answer 16

Diffuse toxic hyperplasia (Graves’ disease) 70%
Toxic multinodular goitre 20%
Toxic adenoma

Question 17

Graves’ disease is more common in who?

Answer 17

Females
20-40yrs
Genetically predisposed

Question 18

What is graves’ disease?

Answer 18

Autoimmune production of anti-TSH receptor antibodies
Stimulate activity and inhibit TSH binding to TSH receptors
Goitre

Question 19

How does Graves’ disease cause ophthalmopathy?

Answer 19

Ocular fibroblasts have TSH receptors

Question 20

How does the thyroid appear histologically in Graves’ disease?

Answer 20

Cell proliferation and increased activity

Question 21

What are the causes of Hypothyroidism?

Answer 21

Hashimoto’s thyroiditis
Iatrogenic
Iodine Deficiency
Congenital

Question 22

Which drugs increase the risk of hypothyroidism?

Answer 22

Methimazole

Lithium

Question 23

Hashimotos thyroiditis is more common in which group?

Answer 23

Females

45-65yrs

Question 24

What is Hashimotos thyroiditis?

Answer 24

Autoimmune Hypothyroidism due to Cytotoxic T cell/cytokine mediated destruction of thyroid epithelial cells

Question 25

Hashimotos thyroiditis causes circulating what?

Answer 25

Antibodies to thyroglobulin | Thyroid peroxidase

Question 26

What causes a multinodular goitre?

Answer 26

Iodine deficiency | Goitrogens

Question 27

How does iodine deficiency/goitrogens cause multinodular goitre?

Answer 27

Impaired synthesis of T3,T4 increases secretion of TSH | Increased TSH = hypertrophy/hyperplasia of epithelium

Question 28

What could thyroid nodules be?

Answer 28

Cyst Follicular adenoma Carcinoma (5%)

Question 29

How are thyroid nodules investigated?

Answer 29

TFTs Ultrasound FNA

Question 30

What are the main types of carcinoma of the thyroid?

Answer 30

``` Differentiated: - Papillary (85%) - Follicular (10-20%) Anaplastic Medullary ```

Question 31

What is a follicular adenoma?

Answer 31

Thyroid neoplasm Mostly non-functioning Encapsulated tumour Microfollicle histology

Question 32

What is a follicular carcinoma?

Answer 32

Malignant cells breach the capsule

Question 33

How do follicular carcinomas metastasise?

Answer 33

Blood | Bones

Question 34

What genetic factors can lead to follicular carcinoma of the thyroid?

Answer 34

RAS mutation | PAX8/PPARG translocation

Question 35

Papillary carcinoma is associated with what?

Answer 35

Ionising radiation | BRAF mutation

Question 36

What is a thyroid medullary carcinoma?

Answer 36

Malignant tumour of C-cells | Produces calcitonin

Question 37

thyroid medullary carcinoma is associated with what?

Answer 37

MEN 2A, 2B Familial FMTC RET proto-oncogene (Prophylactic thyroidectomy)

Question 38

How does Papillary carcinoma appear histologically?

Answer 38

Papillary projections Empty nuclei Psammoma bodies Cystic

Question 39

How does thyroid medullary carcinoma appear histologically?

Answer 39

Tumour cells with amyloid buildup

Question 40

What is the role of PTH?

Answer 40

Regulate Ca2+ Kidney reabsorption Intestinal absorption Active transport from bone

Question 41

How does primary hyperparathyroidism present?

Answer 41

Often assymptomatic | Hypercalcaemia

Question 42

Which gene is associated with parathyroid hyperfunction?

Answer 42

MEN1

Question 43

What are the cell types of the pituitary gland? Which colour do they appear histologically?

Answer 43

Acidophils - pink Basophils - purple Chromophobes - pale

Question 44

What do acidophils secrete?

Answer 44

GH | PRL

Question 45

What do basophils secrete?

Answer 45

ACTH TSH FSH LH

Question 46

What is the most common cause of pituitary hyperfunction?

Answer 46

Pituitary adenoma | carcinoma rare

Question 47

What is the clinical presentation of prolactinoma?

Answer 47

Galactorrhoea | menstrual disorders

Question 48

What is the clinical presentation of GH secreting tumours?

Answer 48

Acromegaly | Gigantism

Question 49

What is the clinical presentation of ACTH secreting tumours?

Answer 49

Cushing's disease

Question 50

What are the most common causes of pituitary hypofunction?

Answer 50

Craniopharyngioma Metastatic cancer Infection (TB, sarcoidosis) Sheehan's syndrome

Question 51

What is Conn's syndrome?

Answer 51

Hyperaldosteronism

Question 52

What is Cushing's syndrome?

Answer 52

Hypercortisolism

Question 53

What are the different types of cushing's syndrome?

Answer 53

Exogenous Endogenous: - ACTH dependent - ACTH independent

Question 54

How does gland enlargement appear differently in dependent and independent Cushing's syndrome?

Answer 54

Dependent - pituitary adenoma - increased ACTH increasing both adrenal glands Independent - adrenal adenoma

Question 55

What are the causes of hyperaldosteronism?

Answer 55

Bilateral idiopathic hyperplasia Adrenal adenoma Decreased renal perfusion

Question 56

What are the causes of Adrenogenital syndromes?

Answer 56

Functioning adrenal tumour Pituitary tumour Congenital adrenal hyperplasia

Question 57

What is the most common cause of acute adrenal insufficiency?

Answer 57

Waterhouse-Friderichsen syndrome (acute adrenal haemorrhage) | Meningococcal septicaemia

Question 58

What is the most common cause of chronic adrenal insufficiency?

Answer 58

``` 1ry - Addison's disease Autoimmune, Infections, Replacement Atrophy Hypoplasia 2ry - pituitary failure ```

Question 59

What are the symptoms of adrenal crisis?

Answer 59

``` Abdominal pain Vomiting Fluid loss Collapse Hypotension ```

Question 60

How does adrenal adenoma present?

Answer 60

Functioning - hyperadrenal syndromes | Nonfunctioning - incidental

Question 61

How does adrenal carcinoma present?

Answer 61

Functioning - virilising Usually large with bleeding Metastasises by lymphatics and blood

Question 62

What is Phaechromocytoma?

Answer 62

Adrenal medulla neuroendocrine cells - usually benign

Question 63

Phaechromocytoma secretes what?

Answer 63

Catecholamines

Question 64

Which gene is associated with Phaechromocytoma?

Answer 64

MEN2

Question 65

What is MEN1?

Answer 65

Multiple endocrine neoplasia Pancreatic, duodenal endocrine tumours Pituitary adenoma

Question 66

What is MEN2A?

Answer 66

Medullary carcinoma of thyroid Phaechromocytoma Parathyroid hyperplasia

Question 67

What is MEN2B?

Answer 67

``` Medullary carcinoma of thyroid Phaechromocytoma Skin neuromas Younger patients Skeletal abnormalities ```