Pathology of the Pituitary and Adrenal Glands Flashcards
What is the anterior pituitary derived from
Rathke’s pouch
What does the anterior pituitary secrete
trophic and non-trophic hormones
Trophic: TSH, ACTH, FSH, LH
Non-trophic: GH and prolactin
What is the posterior pituitary an extension of
neural tissue consisting of modified flail cells and axonal processes
What does the posterior pituitary secrete
ADH and oxytocin
What are the types of cells found in the anterior pituitary
Islands, cords of cells,
Acidophils (Somatotrophs and Mammotrophs)
Basophils (corticotrophs, thyrotophs, gonadotrophs
Chromophobe
What does the posterior pituitary contain
Non-myelinated axons of neurosecretory neurones
What can cause hyper function of the anterior pituitary
Adenoma or carcinoma
What can cause hypo function of the anterior pituitary
Surgery/ radiation Sudden haemorrhage into the gland ischamic necrosis (Sheehan syndrome) Tumours extending into sella Inflammatory conditions (Sarcoidosis)
What part of the pituitary gland does Diabetes insipidus
Posterior pituitary
What does diabetes insipidus result in
Lack of ADH secretion
What does SIADH result in
Ectopic secretion of ADH by tumours
Primary disorder in the pituitary
What is a pituitary adenoma sometimes associated with
MEN1
How can we classify pituitary adenomas
By the cell type / hormone produced
What do large adenomas cause
visual field defects
What can infarction caused by a pituitary adenoma lead to
Panhypopituitarism
If a pituitary adenoma has a mutation of the p53 gene, it is cancerous. True or False
False - they can be benign
What is the most common functional tumour
Prolactinoma
What does prolactinoma result in
infertility
lack of libido
amenorrhoea
What is the second most common pituitary adenoma
Growth hormone secreting
What does a growth hormone secreting adenoma cause
Stimulation of bone growth, cartilage and and connective tissue
What can growth hormone secreting adenomas result in
Gigantism or acromegaly
What is another form of functional pituitary adenoma ?
ACTH secreting
What can be caused as a result of ACTH secreting adenoma
Cushing’s disease
What are some of the causes of panhypopituitarism
Primary or metastatic tumours Traumatic brain injury Subarachnoid haemorrhage Surgery or radiation Granulomatous inflammation (sarcoidosis or tuberculous meningitis Infarction Hypothalmic lesions
What is a craniopharyngioma derived from
remnants of Rathke’s pouch
Describe the growth of craniopharyngioma
Slow growing, often cystic and may calcify
What are some of the symptoms of a craniopharyngioma
headaches and visual disturbances
Children may have growth retardation
What is the prognosis for a craniopharyngioma
Excellent
Where do the adrenal glands sit
Superior and medial to the upper pole of the kidneys
What are the adrenal glands composed of
An outer cortex and a central medulla
What are the 3 zones of the adrenal cortex
Zona glomerulosa
zona fasciculata
zona reticularis
What is produced in the zona glomerulosa
mineralocirticoids
aldosterone
What is produced in the zona fasciculata
Glucocorticoids
Cortisol
What is produced in the zone reticular
sex steroids and glucocorticoids
What innervates the adrenal medulla
pre-synaptic fibres from sympathetic nervous system
What do the neuroendocrine cells in the medulla do
Secrete catecholamines
What is another name for neuroendocrine cells
Chromaffin cells
Adrenal pathology may be a manifestation of what ?
Pituitary disease
Shock/ DIC
Various conditions that may damage or destroy adrenal tissue
What are some of the causes of hyper function of of the cortex of the adrenal gland
Hyperplasia
Adenoma
Carcinoma
What are some of the causes of hypo function of the cortex of the adrenal gland
Acute (Waterhouse-Friderichsen)
Chronic (Addison’s disease)
What is there a deficiency in in congenital adenocortical hyperplasia
The enzyme required for steer biosynthesis
What does altered biosynthesis lead to in terms of adrenocortical hyperplasia
Increased androgen production
What does reduced cortisol stimulate?
ACTH release and cortical hyperplasia
What are some examples of acquired adrenocortical hyperplasia
Pituitary adenoma
Cushing’s disease
Ectopic ACTH
Bilaterla adrenal enlargement
What is the difference between a nodular or diffuse adrenocortical hyperplasia
Diffuse is ACTH driven and nodular is usually ACTH independent
What is required to form aldosterone, cortisol and testosterone
Cholesterol
What is cholesterol converted to in order to produce hormones
Pregnolone
Who is usually affected by an adrenocortial tumour
Mainly adults - both males and females
How is an adrenocortical tumour found
As an incidental finding
Describe an adrenocortical adenoma
Well circumscribed, encapsulated lesion
usually small - up to 2-3cm
yellow / yellow brown cut surface
Composed of cells resembling adrenocortical cells
Well differentiated, small nuclei, rare mitoses
Can be functional, but most likely not
How common is adrenocortical carcinoma
Rare
What can adrenocortical carcinomas resemble
Adenoma
Where can adrenocortical carcinomas spread to
Retroperitoneum, kidney or metastasis to liver, lung and bone
What is the survival rate of adrenocortical carcinoma
5 year is 30-25%
50% dead in 2 years
What are some features that suggest an adrenocortical carcinoma
Large size >50g or >20cm Haemorrhage and necrosis Frequent mitoses, atypical mitosis Lack of clear cells Capsular or vascular invasion
What syndrome is a form of primary hyperaldosteronism
Conn’s syndrome
What syndrome is a form of a Hypercortisolism
Cushings syndrome or disease
What disease is associated with primary adrenocortical insufficiency
Addison’s disease
What are some causes of acute adrenocortical insufficiency
Rapid withdrawal of steroid treatment
Crisis in patients with chronic adrenocortical insufficiency
Massive adrenal haemorrhage (newborn, anticoagulant treatment, DIC, septicaemia infection)
What are some other causes of chronic adrenocortical insufficiency
TB
Fungal infection
HIV
Metastatic malignancy
When do symptoms of primary adrenocortical insufficiency occur
Once >90% of the gland is destroyed
Describe some symptoms of Addison’s disease
Weakness Fatigue Anorexia Nausea Vomiting Weight loss Diarrhoea Hyper pigmentation
Describe the mineralocorticoids in Addison’s disease
K+ retention Na+ loss Hyperkalaemia Hyponatraemia Volume depletion and hypotension
What are the 2 types of adrenal medullary tumours
Phaeochromocytoma
Neuroblastoma
At what age are patients with neuroblastoma diagnosed
18 months
What are 2 important aspects for a prognosis
Age and stage
What predicts a poor outcome in neuroblastoma
Amplification of N-myc and expression of telomerase predict a poor outcome
What is a pheochromocytoma
A neoplasm derived from chromaffin cells of the adrenal medulla
What do phaeochromocytomas secrete
catecholamines
What main thing does phaeochromocytoma cause
Hypertension
What are some complications of phaeochromocytoma
Cardiac failure
Infarction
Arrhythmias
CVA
How is pheochromocytoma diagnosed
Detection of urinary excretion of catecholamines and metabolites
What is pheochromocytoma also known as
the 10% tumour
Why does phaeochromocytoma have the 10% tumour title
10% are extra-adrenal
10% are bilateral
10% are biologically malignant
10% are NOT associated with hypertension
What do malignant phaeochromocytoma tumours ten to be
Large and necrotic
What does MEN stand for
Multiple Endocrine Neoplasia
What is a feature of both MEN1 and MEN2
Phaeochromocytoma
