Case report asserts rare adrenal tumor caused Cushing’s
Woman developed Cushing's syndrome as result of a pheochromocytoma tumor
A woman developed Cushing’s syndrome as a result of a pheochromocytoma, a usually benign non-cancerous tumor that forms in the adrenal glands above the kidneys, a case study from Portugal reports.
Because it’s so rare, “this diagnosis demands a high level of clinical suspicion and should be equated in the presence of severe metabolic changes overlapping [Cushing’s syndrome]’s physical features,” the researchers wrote.
The report, “A Rare Cause of Cushing’s Syndrome: an Adrenocorticotropic Hormone (ACTH)-Secreting Pheochromocytoma,” was published in the journal Cureus.
Cushing’s syndrome occurs when there’s too much of a steroid hormone called cortisol in the body. This often happens because the brain’s pituitary gland produces an excess of adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to produce and release cortisol.
Sometimes, the excess of ACTH comes from outside the pituitary gland. When this happens, the source is said to be ectopic. Lung tumors are a common source of ectopic ACTH. More rarely, other types of hormone-producing tumors, such as a pheochromocytoma, may be the source of excess ACTH.
Now, a team of researchers in Portugal described the case of a 51-year-old woman who developed Cushing’s syndrome secondary to a pheochromocytoma that was found incidentally on an imaging scan.
The woman went to the hospital because she had a sudden increase in blood pressure despite being on antihypertensive medication. She told the doctors that over the past six months she had been feeling increasingly tired and had noticed changes in her appearance.
A physical examination revealed she had sunken and puffy eyes, pale gums, a round face, excessive hair growth, small red spots and darkening in some parts of the skin, a larger-than-normal waistline, and muscle weakness.
Doctors also noticed some bleeding at the back of her eyes, which could be related to high blood pressure. A blood test revealed she had high levels of sugar and low levels of potassium.
Further tests revealed she had higher-than-normal levels of cortisol in the urine over the course of one day. Cortisol levels remained high after an overnight low-dose dexamethasone suppression test, confirming the diagnosis of Cushing’s syndrome. Her blood ACTH levels also were elevated.
Dexamethasone is a medication that normally lowers cortisol levels by suppressing its production. A low-dose dexamethasone suppression test can help tell whether the body is producing too much cortisol, whereas a high-dose suppression test can help pinpoint its source.
However, after taking a low dose of dexamethasone, the woman developed psychotic symptoms, a rare complication that perhaps reflected the severity of her condition. For this reason, no more suppression tests were done.
MRI and CT scans
An MRI brain scan then revealed an asymmetry in the area near the pituitary gland, with the pituitary gland’s stem pushing to the left side. However, another test revealed the pituitary gland was not the source of excess ACTH in her case, ruling out Cushing’s disease as a possible diagnosis.
On a whole-body CT scan, doctors discovered a mass measuring about 44 by 40 millimeters in size (about 1.7 by 1.5 inches). The mass had formed in the left adrenal gland and it did not spread to nearby lymph nodes or blood vessels.
An additional test revealed the mass produced too much catecholamine, a type of hormone that’s important in stress responses. Based on these findings, doctors determined the mass to be a pheochromocytoma.
After undergoing surgery to remove the tumor, the patient’s symptoms resolved.
“In this particular case, considering the tumor’s dimension and the patient’s performance status, surgical resection [removal] remained the best treatment option,” the researchers wrote.
The woman also was given enoxaparin for six weeks to prevent blood clots, hydrocortisone to make up for the steroid drop after surgery, and antibiotics for two weeks to prevent possible infections.
“The total reversal of metabolic and clinical symptoms after surgical resection highlights the need to remember this etiology [cause] when performing a [Cushing’s syndrome] workup,” the researchers wrote.