About Pheochromocytoma

Overview

Pheochromocytoma is a type of tumor that starts in the center of the adrenal gland (the medulla) or in hormone-producing cells called chromaffin cells, which are part of the nervous system and can also be found in areas called sympathetic ganglia. These tumors are characterized by the excessive production and secretion of catecholamines, which are hormones that regulate various bodily functions, including heart rate, blood pressure, and insulin secretion. They are rare tumors. Most pheochromocytomas are benign and only about 10% of those are estimated to spread to other parts of the body.

Causes and Risk Factors

While the exact cause of pheochromocytoma is not fully understood, there are certain risk factors that can increase a person's chances of developing this condition.

Non-modifiable risk factors for pheochromocytoma cannot be changed or controlled. These include:

• Genetic predisposition: If you have a family history of pheochromocytoma or other related cancers, you may have an increased risk of developing this tumor.
• Age: The incidence of pheochromocytoma tends to increase with age.

Modifiable risk factors for pheochromocytoma can be influenced or changed. These include:

• Poor dietary habits, low physical activity, and health problems they cause are key factors that can be changed to improve health.
• It is recommended to maintain a healthy weight, engage in regular physical activity, and follow a healthy diet to reduce the risk of developing this tumor.

Symptoms

The most common early symptoms of pheochromocytoma include:

• Headaches
• Heart palpitations
• Sweating
• High blood pressure (either constant or sporadic)

These symptoms can vary from person to person. Some individuals may experience consistent high blood pressure, while others may have episodes of high blood pressure. The frequency of these episodes can range from several times per day to twice per month.

As pheochromocytoma progresses or becomes more severe, other symptoms may occur, either in episodes or independently. These symptoms can include:

• Nausea
• Stomach pain
• Weight loss
• Rapid heart rate
• Anxiety or a sense of doom
• Feeling shaky
• Being extremely pale
• Mood swings and irritability
• High blood sugar

It's important to note that symptoms may last for seconds or hours and tend to worsen over time as the tumor grows. However, some people with pheochromocytoma may not experience any symptoms at all. In these cases, the condition may only be discovered when undergoing an imaging test for another unrelated condition.

In addition, pheochromocytoma can disrupt the normal functioning of the adrenal glands and increase the risk of an adrenergic crisis. This occurs when bursts of adrenal hormones enter the bloodstream and can lead to further complications.

Diagnosis

To diagnose pheochromocytoma, several examinations, tests, and procedures are commonly performed. These include:

• Physical exam and health history: The healthcare professional does a thorough exam to check for signs of pheochromocytoma, such as high blood pressure, rapid heartbeat or unusual sweating. They also review the patient’s health history, including past illnesses, treatments, and family history, to identify potential risk factors or complications.
• Annual blood pressure monitoring: This involves regular measurement of blood pressure to check for any abnormalities.
• 24-hour urine studies for catecholamine metabolites: This test collects urine over a 24-hour period to measure the levels of catecholamine metabolites, which can indicate the presence of pheochromocytoma.
• Plasma normetanephrine levels: In high-risk families, annual measurement of plasma normetanephrine levels is recommended starting from the age of 8 years. Elevated levels can be a sign of pheochromocytoma.
• Adrenal imaging: This procedure involves using imaging techniques such as CT (computed tomography) scans or MRI (magnetic resonance imaging) scans to visualize the adrenal glands and detect any abnormalities.

To determine the severity of pheochromocytoma, additional examinations, tests, and procedures may be performed. These include:

• CT scan: This procedure uses x-rays and a computer to create detailed images of different body areas like the neck, chest, abdomen, and pelvis. It can help detect if the tumor has spread to other parts of the body.
• MRI (magnetic resonance imaging): This imaging technique uses magnets and radio waves to create detailed pictures of body structures. It can also help determine if the tumor has spread.
• MIBG (metaiodobenzylguanidine) scan: This procedure involves injecting a small amount of radioactive MIBG into a vein to locate neuroendocrine tumors like pheochromocytoma and paraganglioma.

Treatment Options

The goals of treatment for pheochromocytoma are to control symptoms, remove the tumor, and prevent complications. Here are the different treatment options and how they work to achieve these goals:

• Medications:
  • Alpha blockers: These drugs help relax and widen blood vessels, which helps to lower blood pressure. By controlling high blood pressure, alpha blockers can help alleviate symptoms such as headache, sweating, and palpitations.
  • Beta blockers: These drugs work by blocking the effects of adrenaline on the heart, reducing heart rate and blood pressure. By slowing down the heart rate, beta blockers can help control symptoms like rapid heartbeat and tremors.
• Surgery:
  • Surgical removal of the tumor is the preferred treatment for pheochromocytoma. The surgeon may opt for laparoscopic surgery, which involves making small incisions and using specialized tools to remove the tumor. In some cases, if the tumor has spread or is large, the entire adrenal gland may need to be removed.
  • If both adrenal glands are removed, hormone replacement therapy with steroids will be necessary to replace the hormones produced by the adrenal glands.
  • Before surgery, medication may be prescribed to balance heart rate and lower blood pressure in order to minimize complications during the procedure.
• Radiation therapy and chemotherapy:
  • Radiation therapy and chemotherapy are used when pheochromocytoma has spread to other parts of the body. These treatments aim to destroy or shrink cancer cells.

It's important to note that most pheochromocytomas are benign (not cancerous). After surgery, symptoms usually go away. However, regular follow-up visits with a doctor are necessary to monitor for any recurrence or complications.

Medication dosing may be affected by many factors. Check with your health care professional about dosing for your individual situation. Side effects can occur. Check with your health care professional or read the information provided with your medication for side effect information.

Progression or Complications

Over time, if left untreated, pheochromocytoma can lead to several complications and have a significant impact on a person's health. Here's what you need to know:

• Natural progression:
  • Pheochromocytomas can occur at any age, with familial cases typically diagnosed in young adults and sporadic cases more common in older patients.
  • With advances in imaging techniques and routine check-ups, pheochromocytoma is being diagnosed more often in older individuals by chance.
  • Surgical removal of pheochromocytomas is often considered, especially in younger patients. However, concerns have arisen regarding the perioperative management of older individuals undergoing surgery for pheochromocytoma.
  • The elderly population may experience slower recovery and are more prone to postoperative complications due to their physical fragility and the presence of comorbidities.
• Complications:
  • Without treatment, pheochromocytomas can lead to various complications.
  • Hypertensive emergencies: Pheochromocytomas can cause sudden increases in blood pressure, leading to potentially life-threatening problems like aheart attack or stroke.
  • Cardiomyopathy: Prolonged exposure to elevated blood pressure can result in heart muscle disease.
  • Cerebral hemorrhage: Uncontrolled high blood pressure may lead to bleeding in the brain.
  • Pulmonary edema: Fluid buildup in the lungs can occur, causing breathing difficulties.