Pituitary Tumours Flashcards
How common are pituitary tumours?
Relatively common
What percentage of CNS tumours are pituitary tumours?
10-15%
Where do most pituitary tumours arise?
Anterior lobe
Histologically what are all primary tumours?
Benign adenoma
Why can Pituitary tumours be dangerous?
Dangerous due to their location e.g.
they can compress the optic chiasma and cause visual disturbances or blindness
May extend into cavernous sinus
local pressure symptoms
Clinical syndromes associated with abnormal hormone production
What is the Cavernous sinus?
A large channel of venous blood creating a “sinus” cavity bordered by the sphenoid bone and the temporal bone of the skull. The cavernous sinus is an important structure because of its location and its contents which include the third cranial (oculomotor) nerve, the fourth cranial (trochlear) nerve, parts 1 (the ophthalmic nerve) and 2 (the maxillary nerve) of the fifth cranial (trigeminal) nerve, and the sixth cranial (abducens) nerve.
PRL secreting adenoma - hypogonadism+Galactorrhoea
Classified by WHO (2017) what are pituitary tumour cell types?
Corticotrophs
Somatotrophs
Lactotrophs
Thyrotrophs
Gonadotrophs
What were Pituitary tumours classed as in the past?
Acidophilic, eosinophilic, basophilic
What is the most common Pituitary Adenoma?
Lactotrophs are the commonest
Lactotrophs
Secrete prolactin and some may also secrete growth hormone (GH)
Gonadotrophs
30% are non-secreting macroadenomas, these most recently are referred to as “whispering” gonadotrophs) some – secrete luteinising hormone (LH), follicle stimulating hormone (FSH) and thyroid stimulating hormone(TSH)
Corticotrophs
10-15% of cases – secrete adrenocorticotrophic hormone (ACTH)
Somatotrophs
Secrete growth hormone (GH)
Thyroid lesions
Extremely rare (secrete TSH)
Posterior Pituitary
Tumours are occasionally seen called pituicytomas
Generally arise from glial cells
Pituitary Adenoma Tumour Effects
Headache
Visual impairment (blindness, bitemporal hemianopia, tunnel vision
homonymous hemianopia)
Thirst and increased appetite
Loss of recent memory
Partial or complete hypopituitarism
Partial or complete hyperpituitarism
What is Hypopituitarism?
Rare condition
Pituitary secretes inadequate amounts of one or more of its hormones
Can be progressive, eventually under secreting all pituitary hormones
What does Hypopituitarism cause in children?
Failure to grow
Failure of pubertal development
What does Hypopituitarism cause in adults?
Malaise, pale “waxen doll” complexion, intolerance to cold, amenorrhoea, loss of libido, impotence, loss of secondary sexual hair distribution, acute abdominal pain (hypopituitary crisis) and low blood sugar
Who are Craniopharyngioma tumours most common in?
Most often diagnosed in children, teenagers and young adults.
Where do Craniopharyngioma tumours occur?
Tend to grow near the base of the brain, just above the pituitary gland. Craniopharyngiomas do not usually spread, but they occur close to important structures in the brain and can cause problems as they grow. They can cause changes in hormone levels and problems with eyesight. Children with craniopharyngioma can have weight gain and growth problems.
ACROMEGALY hyperactivity – excessive growth hormone production.
Adults over 20-25
Occasionally runs in families
Acromegaly signs and symptoms
Enlarged hands and feet
Coarsened, enlarged facial features
Coarse, oily, thickened skin
Excessive sweating and body odour
Small outgrowths of skin tissue (skin tags)
Fatigue and muscle weakness
A deepened, husky voice due to enlarged vocal cords and sinuses
Severe snoring due to obstruction of the upper airway
Impaired vision
Headaches
Enlarged tongue
Pain and limited joint mobility
Menstrual cycle irregularities in women
Erectile dysfunction in men
Enlarged liver, heart, kidneys, spleen and other organs
Increased chest size (barrel chest)
What is Macroadenoma?
Excess growth hormone
