How to treat pheochromocytoma

Once pheochromocytoma is diagnosed, timely treatment measures should be taken. Surgical removal of the tumor is recommended to reduce the various effects caused by these diseases. At the same time, drug treatment is also necessary. Drug treatment should be used to control and prevent hypertension.

1. Drug treatment

(1) Qualitative and localized diagnosis of pheochromocytoma: Once the diagnosis is confirmed, medication should be used immediately to prevent hypertensive emergencies. The main drugs used are long-acting α-receptor blockers, including phenoxybenzamine and prazosin.

(2) When combined with hypertensive emergencies, phentolamine can be given intravenously. If the treatment is ineffective, sodium nitroprusside can be infused intravenously.

2. Preoperative preparation and drug treatment

(1) α-adrenergic receptor blockers ① Phentolamine: used for differential diagnosis of hypertension, treatment of dangerous hypertension attacks or control of blood pressure during surgery. ② Phenoxybenzamine: Commonly used in preoperative preparation, taken orally before surgery until blood pressure is close to normal. Changes in blood pressure and heart rate in supine and standing positions should be closely monitored during medication. ③ Prazosin, terazosin, and doxazosin: all are selective postsynaptic α1-adrenergic receptor blockers. It can easily cause severe orthostatic hypotension when used, so it should be taken before bedtime and stay in bed as much as possible. ④ Urapidil (Urapidil): It can block α1 and α2 receptors, activate central serotonin 1A receptors, reduce the sympathetic feedback of the medullary cardiovascular regulation center, and thus lower blood pressure without increasing heart rate.

(2) β-adrenergic receptor blockers: After using α-receptor blockers, the excitability of β-receptors is enhanced, causing tachycardia, increased myocardial contractility, and increased myocardial oxygen consumption. β-blockers should be used to improve symptoms.

(3) Calcium channel blockers (CCBs) CCBs can be used for preoperative combined therapy, especially for patients with coronary heart disease or catecholamine cardiomyopathy, or used in combination with α- and β-receptor blockers for long-term antihypertensive treatment. Nifedipine is commonly used.

(4) Angiotensin-converting enzyme inhibitors (ACEI) such as captopril.

(5) Vasodilators: Sodium nitroprusside is a powerful vasodilator, mainly used for patients with pheochromocytoma experiencing hypertensive crisis or with persistently high blood pressure during surgery. Closely monitor blood pressure, adjust drug dosages to prevent a sudden drop in blood pressure, and monitor blood cyanide levels.

(6) Catecholamine synthesis inhibitors: α-Methyl-p-tyrosine is a competitive inhibitor of tyrosine hydroxylase, blocking the synthesis of catecholamines. The dose can be adjusted according to blood pressure and blood and urine catecholamine levels and can be increased gradually. Common side effects include drowsiness, depression, gastrointestinal symptoms, and extrapyramidal symptoms such as Parkinson's disease. The above symptoms may disappear quickly after reducing the dosage or stopping the medication.

3. 131Ⅰ-MIBG treatment

It is mainly used for malignant and surgically unresectable pheochromocytoma.