Pheochromocytoma

Overview

Pheochromocytomas are tumors of the adrenal gland which produce excess adrenaline. Pheochromocytomas arise from the central portion of the adrenal gland which is called the adrenal medulla. The adrenal medulla is responsible for the normal production of adrenaline which our body requires to help maintain blood pressure and to help cope with stressful situations. A tumor which arises from the adrenal medulla and overproduces adrenaline can be a deadly tumor because of the severe elevation in blood pressure it causes.

Symptoms

The classical symptoms of pheos are those attributable to excess adrenaline production. Often these patients will have recurring episodes of sweating, headache, and a feeling of high anxiety. The following symptoms are listed from the most common to the least common: 

  • Headaches (severe) 
  • Excess sweating (generalized) 
  • Racing heart (tachycardia and palpitations)
  • Anxiety / nervousness (feelings of impending death) 
  • Nervous shaking (tremors) 
  • Pain in the lower chest or upper abdomen
  • Nausea (with or without nausea) 
  • Weight loss 
  • Heat intolerance

Causes

Pheochromocytoma may occur as a single tumor or as more than one growth. It usually develops in the center (medulla) of one or both adrenal glands. Sometimes this kind of tumor occurs outside the adrenal gland, usually somewhere else in the abdomen. Less than 10% of pheochromocytomas are cancerous (malignant), meaning they have the potential to spread to other parts of the body. The tumors may occur at any age, but they are most common from early to mid-adulthood. About 10% of the time there is a family history of the disease.

Prevention

Pheochromocytoma cannot be prevented.

Diagnosis

The diagnosis of pheochromocytoma hinges on the treating physician entertaining the diagnosis in the first place. Making the diagnosis is usually straightforward by performing the following tests: 

24 hour urinary catacholamines and metanephrines

This study is designed to measure production of the different types of adrenaline compounds that the adrenal makes. Since the body gets rid of these hormones in the urine, we simply collect a patient's urine for 24 hours and determine if they are over-produced. This test measures different types of adrenaline (epinephrine, norepinephrine, dopamine) as well as the break-down products of these compounds which the liver and kidney have degraded. Since these compounds are concentrated in the urine, this test is very good at making the diagnosis of pheochromocytoma.

Serum catecholamines

This study measures adrenaline compounds in the blood. It is not as sensitive a test for pheochromocytoma as the 24 hour urine test (sometimes the urine test will be positive and the blood test will be negative), but it still can give important information if it shows elevated adrenaline levels.

Prognosis

About 95% of patients who have noncancerous tumors that are removed with surgery are still alive after 5 years. The tumors come back in less than 10% of these patients. Release of the hormones norepinephrine and epinephrine returns to normal after surgery. Less than 50% of patients who have cancerous tumors that spread to the bones, liver, or lung are alive after 5 years.

Treatment

All pheochromocytomas should be removed surgically. The vast majority of patients can be treated with the new technique of minimally invasive Laparoscopic Adrenalectomy. This is now the preferred method for removing pheochromocytomas and is available in most hospitals in the U.S.Treatment involves removing the tumor with surgery. It is important to stabilize blood pressure and pulse with medication before surgery. You may need to stay in the hospital. After surgery, it is necessary to continually monitor all vital signs in an intensive care unit. When the tumor cannot be surgically removed, medication is needed to manage it. Radiation therapy and chemotherapy have not been effective in curing this kind of tumor.