Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Pheochromocytomas are a type of tumor of the adrenal glands that can release
high levels of epinephrine
and norepinephrine. As the name implies, the “ad-renal” glands are located near
the "renal" area. In other words, the adrenal glands are small glands that are
located near the top of the kidneys. One adrenal gland sits on top of
each of the two kidneys.
Despite their small size, the adrenal glands have many functions. They are
complex endocrine (hormone secreting) glands. Cells in different regions of the
adrenal glands have different functions in the endocrine system. There is an
area (zona fasciculata) where the cells secrete cortisol, a hormone similar to
cortisone. There is another area (zona glomerulosa) where cells secrete a
hormone called aldosterone
which helps in water regulation.
There is yet another area, referred to as the adrenal medulla, where the cells
secrete substances called catecholamines -- epinephrine, norepinephrine and dopamine. These are "flight or
fight" hormones. They are responsible in part for that feeling of an
"adrenaline" rush people feel when they are afraid. It is these cells that are
involved in a pheochromocytoma. Basically, a pheochromocytoma is a tumor of
these catecholamine-secreting cells, and that causes the clinical signs and
symptoms we will discuss below. The catecholamine-secreting cells are sometimes
referred to as chromaffin cells, and they are found in other areas of the body
as well as in the adrenal medulla.
Sometimes, pheochromocytomas arise from chromaffin cells that are located
outside of the adrenal gland. In this case, they are termed extra-adrenal
pheochromocytomas or paragangliomas and are usually located in the abdomen.
Pheochromocytomas may occur in persons of any age. The peak incidence is
between the third and the fifth decades of life, but approximately 10% occur in
children. Pheochromocytomas are, fortunately, quite rare (only about 800 new
cases are diagnosed per year in the US) and the majority of them are entirely
benign. Only about 10% of pheochromocytomas are malignant.
Someone with a pheochromocytoma usually has three classic symptoms, headache,
sweating, and heart palpitations (a fast heart beat) in association with
markedly elevated blood pressure (hypertension). Other conditions that may
accompany these classic symptoms are as follows:
anxiety,
nausea,
tremors,
weakness,
abdominal pain, and
weight loss.
Some people, however, never develop symptoms of a pheochromocytoma. Up to 10%
of cases are discovered incidentally, meaning that they are not suspected and
only found when the patient is undergoing diagnostic studies for other
conditions.
Abdominal pain is pain in the belly and can be acute or chronic. Causes include inflammation, distention of an organ, and loss of the blood supply to an
Headaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches, and cluster headaches are
Night sweats are severe hot flashes that occur at night and result in a drenching sweat. In order to distinguish night sweats that arise from medical causes
Anxiety is a feeling of apprehension and fear characterized by physical symptoms. Anxiety disorders are serious medical illnesses that affect approximately
There are four major types of thyroid cancer: papillary, follicular, medullary, and anaplastic thyroid cancer. Tumors on the thyroid are referred to as
Palpitations are unpleasant sensations of irregular and/or forceful beating of the heart. Palpitations can be relieved in many patients by stress reduction,
Tremor is the involuntary movements of one or more parts of the body. Causes of tremor include neurological disorders, neurodegenerative diseases, drugs,
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The
Genetic disease is a disorder or condition caused by abnormalities in a person's genome. Types of genetic inheritance include single inheritance (for example,
Tremor is an unintentional, rhythmic muscle movement involving to-and-fro movements (oscillations) of one or more parts of the body. It is the most common of all involuntary movements and can affect the hands, arms, head"...
