Histopathology 4: Endocrine pathology Flashcards
Which 2 hormones are secreted from the posterior pituitary gland
ADH
Oxytocin
What is the most common pituitary adenoma ?
Prolactinoma
Which cells produce calcitonin ? What is the function of this?
Parafollicular cells (C-cells) - found in thyroid - promotes absorption of calcium by the skeletal system
What is the most common cause of non-toxic goitre world wide ?
Iodine deficiency
What is the most common cause of hyperthyroidism ?
Grave’s disease
List the triad of features seen in Grave’s disease ?
Hyperthyroidism
Exophthalmus
Pretibial myxoedema
Hypothyroidism with Hurthle cells on histology.
Most likely diagnosis ?
Hashimoto’s thyroiditis
Hurthle cells = epithelial cells of the thyroid that become very large with lots of eosinophilic cytoplasm
Most common carcinoma of the thyroid ?
Pappilary carcinoma (75%)
Thyroid histology shows psamomma bodies, empty looking nuclei and intranuclear inclusions (Orphan Annie eye).
Most likely diagnosis ?
Pappilary carcinoma
Congo red staining of the thyroid shows apple green birefringence. The cancer is affecting the parafollicular cells. The patient is known to have MEN2a
Most likely diagnosis and aetiology of this?
Medullary thyroid carcinoma
Calcitonin is produced from the parafolicular cells and is broken down to form amyloid which deposits in the thyroid gland - this amyloid is what the Congo red picks up
What is the most common cause of secondary hyperparathyroidism ?
Renal failure
List 5 physical signs seen in hypoparathyroidism ?
CATS go numb (signs of low Ca)
Convulsions
Arrhythmias
Tetany
Spasms
Numbness
Which paediatric tumour affects the adrenal medulla ?
Name of tumour in adults
Neuroblastoma
Phaeochromocytoma
NB these both secrete catecholamines
List 3 syndromes which feature phaeochromocytomas?
MEN
von Hippel Lindau
Sturge-Weber
what cells make up the anterior pituitary
epithelial
blood supply from pituitary portal system
What cells make up the posterior pituitary
nerve cells
supplied by nerves originating in the supraoptic nucleus and periventricular nucleus
list 3 main effects of functioning pituitary adenomas
prolactinomas - amenorrhoea…
GH adenomas - gigantism, acromegaly, DM, muscle weakness, hypertension, congestive cardiac failure
Corticotroph cell adenoma - Cushing’s
**PLEASE CLOZE DELETE EACH ANSWER AND DO THEM ALL AS C1**
causes of hypopituitarism (3)
- non-secreting pituitary adenoma
- ischaemic necrosis - esp post partum ( Sheehan syndrome), DIC, SCA, elevated ICP, shock
- iatrogenic - ablation of pituitary by surgery or radiation
what 2 syndromes involve ADH
- diabetes insipidus: large amounts of dilute urine
- SIADH: presents with profound hyponatraemia (from dilutional effects)
local mass effect of pituitary tumours
- compression of optic chiasm - bitemporal hemianopia
- larger - raised ICP
- severe - obstructive hydrocephalus
4 primary causes of thyrotoxicosis (high T3/4)
- graves
- hyperfunctioning multinodular goitre
- hyperfunctioning adenoma
- thyroiditis
causes of hypothyroidism (which is most common)
primary:
- post ablative (after surgery/radiotherapy)
- AI (hashimotos)
- iodine deficiency
secondary:
- pit/hypothalamic failure (MOST COMMON)
features of hashimotos thyroiditis
Histology
- painless enlargement of thyroid gland
- lots of lymphoid cells + Hurthle cells (epithelial cells of the thyroid become very large with lots of eosinophilic cytoplasm)
what are thyroid adenomas
- benign neoplasms of the follicular epithelium
- usually solitary
- well circumscribed
- well formed capsule
- small proportion functional and cause thyrotoxicosis, but need to examine the capsule for invasion to exclude follicular carcinoma
RF for thyroid carcinoma
genetics eg MEN
ionising radiation
Size of microadenoma
<1cm
Where are parafollicular cells (C cells) found? What do they do?
Thyroid gland - synthesise calcitonin which promotes absorption of calcium by the skeletal system
Multinodular vs non-toxic goitre
- Goitre = enlargement of thyroid
- Non-toxic = NOT overproducing thyroid hormones
- Multinodular = hyperfunctioning nodule, can lead to hyperthyroidism
Antibodies seen in Grave’s disease
Antibodies to the TSH receptor (these stimulate thyroid hormone release)
Features suggestive of neoplasia of thyroid gland
- Solitary rather than multiple
- Solid rather than cystic
- Younger patients
- Males > females
- Nodules that do NOT take up radioiodine (cold nodules) are more likely to be neoplastic
Where might papillary carcinoma of thyroid gland metastasise?
cervical lymph node
Where do follicular carcinoma of thyroid gland metastasise?
via the bloodstream to the lungs, bone and liver
Age group affected by anaplastic thryoid gland carcinoma
Elderly
What type of thyroid carcinoma arises from the Parafollicular/ C cells of the thyroid?
- Medullary
Most common cause of Hypoparathyroidism
Surgical ablation
What part of adrenal gland cortex secretes noradrenaline + adrenaline?
Medulla (proper inside part - below zona reticularis)
Aetiology of Hyperparathyroidism
- 80-90% are due to a solitary adenoma
- 10-20% are due to hyperplasia of ALL four glands (part of MEN1)
- NB only 1% due to carcinoma
What happens to bone in hyperPTH?
Bone resorption with thinning of the cortex and cyst formation (osteitis fibrosa cystica)
Condition where an adenoma causes increase in aldosterone
Another cause of hyperaldosteronism
Conn’s syndrome (primary hyperaldosteronism)
bilateral adrenal hyperplasia (60% cases)
NB get HTN (since retain Na) and low K (increased excretion) in hyperaldosteronism
Aetiology of Cushing’s
- XS cortisol
- Most due to exogenous glucocorticoids XS
Endogenous causes:
- pituitary adenoma secreting ACTH (Cushing’s disease)
- ectopic ACTH (small cell lung cancer)
Most common type of adrenocortical neoplasms
Adenomas (Cushing’s, Conn’s)
Name of catecholamine-secreting tumours arise OUTSIDE of the adrenal
paragangliomas (found on side of neck or spine)
Rule of 10s in causes of Phaeochromocytoma
- 10% arise in association with a familial syndrome: MEN 2A and 2B, Von Hippel Lindau, Sturge-Weber
- 10% are bilateral
- 10% are malignant
- 10% of catecholamine-secreting tumours arise OUTSIDE of the adrenal (paragangliomas)
Main aetiology of Addison’s Disease (primary chronic Adrenal Insufficiency)
Autoimmune (75-90%)
What is MEN?
- Multiple Endocrine Neoplasia (MEN) Syndromes
- group of inherited diseases resulting in proliferative lesions of multiple endocrine organs
- Arise in ≥ 1 endocrine organ OR may be multi-focal within one endocrine organ
- Tumours are often preceded by hyperplasia
Tumours in MEN1 (3)
Tumours in MEN2A (3)
Tumours in MEN2B (3)
- Pituitary adenoma
- Parathyroid hyperplasia
- Pancreatic tumours
- Medullary thyroid carcinoma
- Parathyroid hyperplasia
- Phaeochromocytoma
- Same as 2A
- Marfanoid body habitus
- Mucosal neoplasms
