Pheochromocytoma

Question 1

Pheochromocytoma

Answer 1

• rare adrenal gland tumor where cells darken in colour when they form tumors
• when chromaffin cells begin to divide uncontrollably

Question 2

Distribution of tumors

Answer 2

1. Typically 1 adrenal gand
2. Rarely in both
3. Occasionally at carotid arteries/bladder/abdominal aorta

Question 3

Causes

Answer 3

1. Sporadically
2. Multiple endocrine neoplasia type 2A and type 2B
   - mutation in RET protooncogene becomes oncogene
3. Von hippel Lindau - mutation in VHL tumor suppressor protein which causes uncontrolled proliferation of tumors
4. Neurofibromatosis Type 1
   - mutation in NF1 gene which encodes for tumor suppressor called neurofibromin

Question 4

Pathophys

Answer 4

1. Tumors secrete excess catcholamines into blood
2. Stress//Physical exercise// food containing tyramine can trigger catecholamine
3. Cause smooth muscle in blood vessels contract
4. Increase peripheral vascular resistance
5. Hypertension

Question 5

Hypertensive urgency

Answer 5

1. Blood pressure rises beyond 180>120 mmHg
2. Small vessels may break in heart or brain or eyes
3. Haemorrhage and ischaemia
4. Hypertensive emergency

Question 6

Hypertensive emergecy

Answer 6

if small blood vessel was within
• Heart -> congestive heart failure
• Brain -> Ischaemia//Stroke
• Eye -> Retinal Haemorrhage
• Kidney -> Kidney failure

Question 7

Symptoms

Answer 7

1. high blood pressure
2. Anxiety
3. Headache
4. Sweating
5. Palpitation

Question 8

Diagnosis

Answer 8

1. Checking for high levels of catecholamaine in blood or urine
2. Metanephrine ( breakdown product) test in urine
3. Ultrasound/CT -> Identify location ->

Question 9

Medication

Answer 9

1. Hypertensive crisis -> medications to decrease bp

2. Surgery to remove tumor