Synonyms in a broader sense
Definition
Pheochromocytoma is a disease in which a tumor produces an excess of hormones. This hormone-producing tumor consists of cells that originate from the stress-mediated nervous system. In 90% of cases the tumor is located in the adrenal gland, in 10% it is located in the spinal column.
The pheochromocytoma produces the stress-mediating hormones adrenalin and noradrenalin in large quantities and releases them into the bloodstream. Noradrenaline and adrenaline are so-called catecholamines. Adrenaline causes vasoconstriction, while noradrenaline has a vasodilating effect and causes the heart to increase its rate and beat.
Most of the time, the pheochromocytoma produces adrenaline, which is why vasoconstriction occurs and high blood pressure is very common in the affected patients. In the vast majority of patients, the pheochromocytoma is unilateral, in a few cases it is a bilateral hormone producing tumor. In 90% of cases the pheochromocytoma is a benign tumor, 10% of the tumors are malignant.
Pheochromocytoma can be the expression of a familial disease associated with tumors of different organs. This disease is called MEN 2 syndrome, where MEN stands for multiple endocrine neoplasia. It is a disease in which multiple (=multiple) endocrine (=hormonal) tumors (=neoplasias) occur.
Occurrence in the population
Every year, one person per 100,000 falls ill with a pheochromocytoma. In less than 1% of cases of hypertension, pheochromocytoma is responsible for high blood pressure (arterial hypertension).
Diagnosis
The increase of stress-mediating hormones in the body, as is the case with pheochromocytoma, can be diagnosed by a urine test: The patient collects his urine over 24 hours in a specially prepared vessel. This collected urine is tested for the hormones themselves as well as the breakdown products of the catecholamines. If hormones or degradation products are found in increased amounts, it is proven that there is an overproduction of hormones.
Values above 200 ng (spoken: nanograms) per liter indicate a pathological change in hormone production in the body, while values below 50 ng represent a normal finding. If there is a clinical suspicion of pheochromocytoma, drugs that can falsify the diagnosis, such as tetracyclines, theophylline or clonidine, should be discontinued two weeks before the examination. Confirmation of the suspicion of a hormone producing tumor is obtained by a test: In a blood test, the amount of catecholamine in the blood is determined.
The patient then receives the drug clonidine. The blood is again examined for catecholamines. In a healthy person, clonidine reduces the amount of catecholamine in the blood, whereas in a patient with pheochromocytoma the amount remains unchanged.
This effect occurs because clonidine inhibits the normal production of catecholamines in the adrenal gland. The pheochromocytoma is decoupled from the body’s hormone regulatory circuit, the tumor produces an excess of hormones independently and independently of the body’s normal requirements. Consequently, hormone production cannot be inhibited by the medication administered.
To locate the location of the tumor in the body, various examination methods are used, such as ultrasound, computer tomography (CT) or magnetic resonance imaging (MRI). The patient should also be examined for the presence of MEN-2 syndrome: New formations of the thyroid and parathyroid glands, such as those found in MEN-2 syndrome, must be investigated. Typical symptoms of pheochromocytoma are high blood pressure, headaches, palpitations, sweating, nausea and vomiting, and panic attacks.
The symptoms can be caused by exertion, emotional stress or when pressing on the abdomen. The patients often notice an inner restlessness. They have a rather pale skin and, when presenting themselves to the doctor, they state that they have lost weight recently. In one third of the cases, there are elevated blood sugar levels (diabetes mellitus) and increased excretion of sugar in the urine.
