Pheochromocytoma

Pheochromocytoma is a rare tumor that develops in the inner part of the adrenal gland (called the medulla).

The adrenal glands are small, triangular glands sitting atop each kidney. They produce important hormones including cortisol, adrenaline, aldosterone, and androgens.

With a pheochromocytoma, the adrenal gland releases excessive amounts of stress hormones, leading to sudden episodes or attacks of severe high blood pressure, headaches, rapid heartbeat, and sweating.

Most pheochromocytomas are benign, meaning they are not cancerous. About 10-15% of pheochromocytomas are cancerous.

Treatment for pheochromocytoma usually involves surgery to remove the tumor.

Learn more about pheochromocytoma, including its definition, causes, symptoms, diagnosis, treatment, and potential risks and complications.

What is pheochromocytoma?

Pheochromocytoma is a neuroendocrine tumor that originates from the chromaffin cells of the adrenal medulla. These tumors lead to overproduction of catecholamines, which are hormones that can cause severe hypertension (high blood pressure) and other potentially life-threatening symptoms.

Causes of pheochromocytoma

The exact cause of pheochromocytoma is not known. Pheochromocytoma tumors form in chromaffin cells in the center of the adrenal gland. There are hereditary factors that can be passed down, including:

• Multiple endocrine neoplasia type 2 (MEN 2): An inherited disorder that increases the risk of developing pheochromocytomas, as well as medullary thyroid cancer and hyperparathyroidism.
• Von Hippel-Lindau disease: A genetic condition associated with tumors and cysts in multiple organs, including pheochromocytomas.
• Neurofibromatosis type 1: A genetic disorder characterized by the development of multiple benign tumors (neurofibromas) and an increased risk of pheochromocytomas.
• Familial paraganglioma syndromes: Genetic predispositions to develop paragangliomas and pheochromocytomas.

In many cases, the exact cause of pheochromocytomas remains unknown, though it involves abnormal growth of adrenal medulla cells leading to excess catecholamine production.

Symptoms of pheochromocytoma

Pheochromocytoma symptoms can come and go in episodes or “attacks.” These symptoms are caused by too much adrenaline or noradrenaline being released. Symptoms can include:

• Hypertension: Severe and often episodic high blood pressure, which may be resistant to standard antihypertensive medications.
• Headaches: Intense and recurrent headaches.
• Palpitations: Rapid, irregular heartbeats.
• Diaphoresis: Excessive sweating.
• Tremors: Shaking or trembling, especially in the hands.
• Anxiety or panic attacks: Feelings of anxiety or impending doom.
• Pallor: Pale skin.
• Weight loss: Unexplained weight loss.
• Abdominal pain: Pain or discomfort in the abdomen.
• Symptoms triggered by certain activities: Physical exertion, stress, surgery, or consumption of tyramine-rich foods (e.g., aged cheese, smoked meats) can trigger symptoms.

Diagnosis of pheochromocytoma

Medical history and physical examination

• Symptom assessment: Detailed inquiry about symptoms such as hypertension, headaches, palpitations, sweating, and anxiety.
• Medical history: Review of risk factors, including family history of pheochromocytoma or related genetic syndromes.
• Physical examination: Examination focused on identifying signs of hypertension and other characteristic symptoms of pheochromocytoma.

Diagnostic tests

• Biochemical tests:
  • 24-hour urinary catecholamines and metanephrines: Measures the levels of catecholamines and their metabolites in urine collected over 24 hours.
  • Plasma-free metanephrines: Measures the levels of catecholamine metabolites in the blood, providing a highly sensitive test for pheochromocytoma.
• Imaging studies:
  • Abdominal CT scan or MRI: Detailed imaging to visualize the adrenal glands and detect the presence of a tumor.
  • MIBG (metaiodobenzylguanidine) scintigraphy: A nuclear medicine scan using a radiotracer to detect sympathetic tissue tumors, including pheochromocytomas and paragangliomas.
  • PET scan: Advanced imaging to localize tumors and assess for metastasis.
• Genetic testing: Recommended for patients with a family history or clinical suspicion of hereditary syndromes associated with pheochromocytoma.

How is pheochromocytoma treated?

Treatment for pheochromocytoma usually involves surgery. Before surgery, your health care provider may prescribe certain medications to manage symptoms of the pheochromocytoma and help you get ready for surgery.

Adrenalectomy: The primary treatment for pheochromocytoma involves surgical removal of the tumor, called adrenalectomy. This procedure is often performed using a minimally invasive approach. This aims to remove the source of excess catecholamine production and resolve symptoms.

After surgery, you will have regular follow-up visits with your health care provider to monitor blood pressure, catecholamine levels, and overall endocrine function to ensure successful treatment and detect any recurrence.

Potential risks and complications

Complications of untreated pheochromocytoma

• Cardiovascular risks: Increased risk of heart disease, heart attacks, strokes, and hypertensive crises due to excessive catecholamine levels.
• Hypertensive crisis: Sudden, severe increase in blood pressure that can be life-threatening, leading to organ damage.
• End-organ damage: Chronic hypertension can lead to damage to organs such as the heart, kidneys, and eyes.

Long-term considerations

• Ongoing monitoring: Regular follow-up with blood tests to monitor catecholamine levels, blood pressure, and detect any recurrence of the tumor.
• Genetic counseling: For patients with hereditary syndromes, genetic counseling and testing for family members.

Impact on quality of life

• Symptom relief: Effective treatment can alleviate symptoms, normalize blood pressure, and significantly improve overall well-being and quality of life.
• Informed decision-making: Accurate diagnosis aids in making informed decisions about treatment and preventive measures.
• Emotional support: Providing counseling and support to address anxiety, depression, and the psychological impact of living with pheochromocytoma or undergoing treatment.

Pheochromocytoma is a rare yet potentially life-threatening condition that requires early diagnosis and appropriate intervention with medical treatments or surgical removal to manage symptoms and prevent complications. Understanding the causes, symptoms, diagnostic methods, and treatment options is essential for effective management. If you or a loved one are experiencing symptoms or have risk factors for pheochromocytoma, consulting with a health care provider, endocrinologist, or specialized surgeon will help determine the need for further evaluation and develop a suitable treatment plan tailored to your specific needs and circumstances.