What is a Pheochromocytoma?
A pheochromocytoma is a neuroendocrine tumor arising from the adrenal glands that produces high amounts of catecholamines that include metanephrine, normetanephrine, epinephrine, norepinephrine and dopamine as well as their metabolites. Patients who are diagnosed with pheochromocytomas typically show excessive amounts of these hormones / metabolites, particularly metanephrines although that is not always the case and they may be found on radio graphic screening for other conditions or incidentally at the time of a surgical procedure.
Fewer than 20% of these tumors are metastatic (this number is much higher in those patients with a SDHB gene mutation) and a surgical resection or removal of pheochromocytoma is the recommended treatment. Surgery should only be performed at centers experienced in the management of this rare disorder.
What is a Paraganglioma?
Paragangliomas, often described as extra-adrenal pheochromocytomas, are closely related though less common tumors that originate in the ganglia of the sympathetic nervous system and are named based upon the primary anatomical site of origin. These tumors can be found anywhere in the body but are typically found in the skull, neck, chest, abdomen, pelvis and urinary bladder areas.
What are the Signs & Symptoms?
The most common sign of a pheochromocytoma or a paraganglioma is high blood pressure. Other symptoms include but are not limited to
- Pain due to a mass effect
- Elevated heart rate
- High levels of anxiety
- Excessive sweating
- Weight loss
- Elevated blood glucose levels without proven diabetes mellitus
How is it diagnosed?
The most effective way to diagnose pheochromocytomas or paragangliomas is through biochemical testing that measures catecholamines and metanephrines in plasma or urine.
Experts suggest that analysis of free metanephrines in blood plasma is the most accurate test for detecting these tumors.
Urine tests, although not quite as sensitive as plasma testing, are still considered effective in diagnosis.
Other diagnostic tests that are used include CT scan with the use of various chemicals and MRI. These scans should be performed in centers that have a level of comfort in diagnosing this disease and offer at least FDG-PET scanning. Without the proper scans, a complete picture of the tumor locations, which are usually multifocal, cannot be made. It is as a result of these scans that a surgical plan for treatment and the sub-specialist surgeons that will participate are chosen.
What treatment options exist?
Surgical resection of a tumor is the treatment of choice and usually results in a cure of the hypertension. Careful preoperative management is required to control blood pressure, heart rate, fluid volume, and to prevent intraoperative hypertensive crises.
Where can I go for treatment?
The SDHB PheoPara Coalition has listed some of the major treatment centers on our website. Please go to the Treatment Centers tab on the home page and click once then click again on center to get more detailed information.
What resources are available to patients that been diagnosed with the disease?
In addition to the SDHB PheoPara Coalition website, there are a number of other websites available through the internet that provide relevant and useful information for patients and healthcare providers alike. We have also listed some resources and sister organizations on our website which can be accessed by going to our home page and clicking on the resources tab.
Can the disease be genetically passed on from one family member to another?
The simple answer is yes and if another member of your family has the disease, then genetic testing and counselling is highly recommended. While experts differ in terms of the percentages, it is generally thought that approximately 60% of those cases that present are sporadic and occur by chance. About 40% of the cases or greater are heriditary and both males and females can pass the gene to their children. Carrying the gene does not necessarily mean it will result in a pheochromocytoma or paraganglioma but in some heriditary forms, the chance is estimated to be about 50% or even higher.