ADRENOMEDULLARY DYSFXN

Question 1

Front

Answer 1

Back

Question 2

What is pheochromocytoma (PHCM)?

Answer 2

PHCM is a tumor of the adrenal medulla that secretes catecholamines

Question 3

What percentage of pheochromocytomas are malignant?

Answer 3

Approximately 10% of pheochromocytomas are malignant

Question 4

What are the common clinical features of pheochromocytoma?

Answer 4

Features include hypertension

Question 5

What is the clonidine suppression test used for?

Answer 5

It evaluates pheochromocytoma by suppressing catecholamine release in normal subjects but not in affected patients.

Question 6

What is the treatment for pheochromocytoma?

Answer 6

The primary treatment is surgical removal of the tumor

Question 7

What dietary restrictions are required before biochemical tests for pheochromocytoma?

Answer 7

Patients should avoid foods like bananas

Question 8

What is the significance of metanephrine measurement in pheochromocytoma diagnosis?

Answer 8

Metanephrines are reliable markers for pheochromocytoma

Question 9

What imaging modalities are used to localize pheochromocytomas?

Answer 9

CT

Question 10

What are APUD tumors?

Answer 10

APUD tumors are a group of neoplasms

Question 11

What are paragangliomas?

Answer 11

Paragangliomas are extra-adrenal pheochromocytomas found in chromaffin tissues derived from neuroectoderm.

Question 12

What is the role of metyrosine in pheochromocytoma management?

Answer 12

Metyrosine inhibits catecholamine synthesis and is used pre-operatively to reduce tumor activity.

Question 13

What biochemical tests are used for pheochromocytoma screening?

Answer 13

Tests include measurements of catecholamines

Question 14

What is the prognosis of benign pheochromocytoma after surgery?

Answer 14

The 5-year survival rate exceeds 95%

Question 15

What is the importance of follow-up in pheochromocytoma patients?

Answer 15

Follow-up includes monitoring catecholamine levels and blood pressure to detect recurrence or persistent hypertension.

Question 16

What are the complications of untreated pheochromocytoma?

Answer 16

Complications include severe hypertension

Question 17

What is multiple endocrine neoplasia (MEN) syndrome?

Answer 17

MEN is a hereditary disorder associated with endocrine tumors

Question 18

What is the common cause of carbohydrate intolerance in pheochromocytoma patients?

Answer 18

It is due to catecholamine-induced insulin suppression and increased hepatic glucose output.

Question 19

What are the features of malignant pheochromocytoma?

Answer 19

Features include metastases

Question 20

What are the indications for genetic testing in pheochromocytoma?

Answer 20

Genetic testing is indicated in cases of bilateral tumors

Question 21

What are the dietary sources that can interfere with biochemical tests for pheochromocytoma?

Answer 21

Bananas

Question 22

What is the common cardiovascular manifestation in pheochromocytoma?

Answer 22

Hypertension

Question 23

What role does histamine play in pheochromocytoma paroxysms?

Answer 23

Histamine can precipitate severe paroxysms by causing catecholamine release from the tumor.

Question 24

How does a pheochromocytoma crisis typically present?

Answer 24

Crisis presents with abrupt onset of headache

Question 25

What are the common catecholamines secreted by pheochromocytomas?

Answer 25

Adrenal pheochromocytomas secrete epinephrine and norepinephrine

Question 26

How does clonidine suppress catecholamine secretion in normal subjects?

Answer 26

Clonidine inhibits catecholamine release via central alpha-2 adrenergic receptors but fails to suppress secretion in pheochromocytoma.