Adrenal medulla & Phaemochromocytoma

Question 1

what hormones are secreted by the adrenal medulla

Answer 1

adrenaline and noradrenaline(catecholamines)

Question 2

what are catecholamines derived from

Answer 2

derived from tyrosine which is then converted to dopamine, and then into catecholamines

Question 3

what are some of the possible symptoms seen in phaeochromocytoma
(not in classical triad)

Answer 3

palpitations, breathlessness, weight loss, anxiety, constipation

Question 4

what’s the difference between a phaeochromocytoma and a paraganglioma

Answer 4

same thing except
phaeochromocytoma = in the adrenal medulla
paraganglioma = extra adrenal(sympathetic chain)

Question 5

how common is phaeochromocytoma

Answer 5

8/1,000,000 per annum

Question 6

describe the importance of diagnosis of phaeochromocytoma

Answer 6

it is curable, and potentially fatal with a high rate of post-mortem diagnosis

Question 7

describe the onset and time pf diagnosis of phaeochromocytoma

Answer 7

insidious onset

mean diagnosis 4.5 years after first symptoms

Question 8

what are some differential diagnosis of phaeochromocytoma, and can often be mistaken for

Answer 8

anxiety, menopause, thyrotoxicosis, arrhythmia

Question 9

what is the classical triad of symptoms seen in 90% of phaeochromocytoma patients

Answer 9

hypertension, sweating, headaches

Question 10

what diagnostic tests can be normal at times even if patients has phaeochromocytoma

Answer 10

24 hour urinary catecholamines in 7% cases, also in 10% cases no symptoms

Question 11

what are some of the possible signs that can be seen in phaeochromocytoma

Answer 11

hypertension(most common), postural hypotension, pallor, bradycardia/tachycardia, pyrexia

Question 12

what biochemical abnormalities may be present in phaeochromocytoma

Answer 12

hyperglycaemia, low K, high haematocrit, mild hypercalcaemia, lactic acidosis

Question 13

what % of phaeochromocytomas are malignant

Answer 13

around 10%

Question 14

what patients should be investigated for phaeochromocytomas

Answer 14

those with; family members with syndromes, resistant hypertension, young(<50) hypertension, classical triad of symptoms, hypertension + hyperglycaemia, incidentally identified adrenal tumours

Question 15

how is catecholamine excess confirmed in diagnostic process of phaeochromocytoma
(note catecholamine excess doesn’t mean its definitely phaeochromocytoma)

Answer 15

urine, 2 x 24hour catecholamine and metanephrines(ensure no foods or drugs that may interfere with results)
plasma metanephrines can improve specificity(ideally done at time of symptoms)

Question 16

what imaging can be used in diagnosis of phaeochromocytoma

Answer 16

MRI(abdo and whole body), MIBG, PET scan

Question 17

what is the treatment of choice for phaechromocytoma

Answer 17

surgery, laparoscopic, total excision wherever possible if not tumour de-bulking

Question 18

what treatment is given for phaeochromocytoma before surgery is considered

Answer 18

full alpha and beta blockade, fluid and/or blood replacement

Question 19

describe what a full alpha and beta blockade in phaeochromocytoma treatment involves

Answer 19

alpha blocker(phenoxybenzamine) given first and once established given beta blocker(propanolol, atenolol or metoprolol)
(A before B)

Question 20

what treatment may be needed after surgery for phaeochromocytoma

Answer 20

chemotherapy if malignant, possibly radio-labelled MIBG, long term follow up in all, considered for genetic testing

Question 21

what are some clinical syndromes associated with phaeochromocytomas

Answer 21

MEN2, Von-Lindau syndrome, succinate dehydrogenase mutations, neurofibromatosis