PITUITARY TUMOURS Flashcards
3 types of pituitary tumour
- non-functioning
- prolactinoma
- acromegaly
what do you call a pituitary tumour >1cm
macroadenoma
what do you call a pituitary tumour <1cm
microadenoma
what is a non-functioning tumour
a pituitary tumour which does not cause excess secretion of pituitary hormones
how does a non-functioning tumour cause pathology
by growling v large and compressing surrounding structures
what structures are compressed by macro adenoma pituitary tumours
optic chiasm
cranial nerves 3,4,6
what are the symptoms of a non-functioning tumour
panhypopituitarism
hypoadrenalisim hypothyroidism hypogonadism diabetes insipidus GH deficiency
what is a prolactinoma
a functional pituitary tumour which secreted prolactin
what cells produce prolactin
lactotroph cells
what is prolactin normally released for
stimulating breast milk production in pregnancy
what are the effects of prolactin on dopamine and GnRH
increases dopamine (which surpassed prolactin)
decreased GnRH which causes a decrease in FSH and LH
what are the symptoms of a micro prolactinoma
none
what are the symptoms of a macro prolactinoma experienced by both men and women
bitemporal hemianopia
headaches
reduced fertility
reduced libido
what are the female symptoms of prolactinoma
galactorrhea - milky discharge from breasts
amenorrhea - no periods
vaginal dryness
brittle bones
what are the male symptoms of prolactinoma
genecomastia - breast development
erectile dysfunction
how do you diagnose prolactinoma
raised serum prolactin levels
MRI pituitary
Pituitary function tests
what is the first line drug for prolactinoma
CARBERGOLINE
dopamine agonists
what are 3 side effects of dopamine agonists
nausea/vomiting
low mood
fibrosis
when is surgery used for prolactinoma
macroadenoma or failed medial therapy
if surgery not possible -radiotherapy
what is acromegaly
a benign functional tumour of the pituitary which secreted GROWTH HORMONE
Symptoms of acromegaly
giantism thickened soft tissues (jaw hands, skin, sweating) snoring/sleep apnoea hypertension headaches diabetes mellitus local pituitary effects early CV death colon cancer and colonic polyps
how do you diagnose acromegaly
IGF1 levels in blood
Glucose tolerance test
how does glucose tolerance test work
normally GH is released during hypoglycaemia and should be suppressed with hyperglycaemia
if GH is not suppressed after inducing hyperglycaemia OR paradoxically increases OR remains high for a long time after then there is acromegaly
1st line treatment for acromegaly
SURGERY
check glucose tolerance test after and if still high may need drug/radio therapy
