Rare Case Report: Bleeding Pituitary Tumor Caused Cushing’s
Researchers reported a case of Cushing’s disease in a 33-year-old man caused by a rare, large pituitary gland tumor with regional bleeding and cell death. Its removal resolved the disease, but resulted in adrenal insufficiency and the need for hormone replacement therapy.
This case adds to previous reports suggesting that this type of tumor, called sparsely granulated corticotroph tumor (SGCT), is associated with larger size and a longer time to recover the hypothalamic-pituitary-adrenal axis after surgery.
The case report, “Sparsely Granulated Corticotroph Pituitary Macroadenoma Presenting with Pituitary Apoplexy Resulting in Remission of Hypercortisolism,” was published in the journal AACE Clinical Case Reports.
Cushing’s disease is characterized by excessive levels of cortisol, a steroid hormone produced by the adrenal glands, which sit atop the kidneys. Given its role in several bodily processes, excess levels of cortisol lead to Cushing’s wide variety of physical, hormonal, and psychological symptoms.
Cushing’s disease is commonly caused by benign pituitary gland tumors, called corticotroph pituitary adenomas, that overly produce ACTH, a hormone that stimulates cortisol production by the adrenal glands.
These tumors can be divided further based on specific staining in lab tests and levels of ACTH production: densely granulated, sparsely granulated, and Crooke’s cell tumors.
Estimated to account for 19–29% of corticotroph adenomas, SGCTs are significantly larger, resistant to specific staining, and show low ACTH levels. They also have been associated with longer duration of Cushing’s prior to diagnosis, larger tumor size at diagnosis, lower immediate remission rate and longer recovery time of hypothalamic-pituitary-adrenal axis after surgery.
While most corticotroph pituitary adenomas are smaller than one centimeter in diameter (microadenomas), 7–23% of Cushing’s patients are diagnosed with a larger tumor, called macroadenoma.
“It is even rarer for a corticotroph macroadenoma to present with apoplexy, with only a handful of case reports or series in the literature,” the researchers wrote.
Pituitary apoplexy is a potentially life-threatening hormonal and neurosurgical emergency caused by bleeding or infarction (cell death due to impaired blood flow) in the pituitary gland, commonly due to a tumor.
Now, a team of researchers in Canada described the case of a 33-year-old man with a rare, sparsely granulated macroadenoma with apoplexy.
The man came to a community hospital complaining of a sudden and severe headache accompanied by low blood pressure, nausea, vomiting, partial peripheral blindness, and double vision.
Further examination revealed common signs of Cushing’s disease, such as a moon face with red cheeks, abdominal fat and purple stretch marks, as well as a buildup of fat between the shoulders and above the collarbones.
In retrospect, the man reported a three-year history of other symptoms characteristic of Cushing’s, such as increased central obesity, easy bruising, fatigue, reduced libido, and erectile dysfunction.
At the hospital, lab work, which did not assess ACTH, showed normal levels of several hormones, but cortisol was abnormally high and testosterone (the male sex hormone) extremely low — further supporting a Cushing’s diagnosis.
Notably, similar to cortisol, testosterone is regulated by the hypothalamus-pituitary-adrenal axis; the hypothalamus is another gland in the brain.
An MRI scan revealed a 3.2-centimeter corticotroph pituitary adenoma with a bleeding and that was compressing in a region of the optic nerve, likely explaining his vision symptoms.
The man underwent emergency surgery to remove the tumor, which, upon analysis, was found to be a SGCT with some ACTH production and with regional bleeding and cell death.
After surgery, cortisol levels fell below the normal range and ACTH levels were normal, but those of TSH — a hormone generated by the pituitary that stimulates thyroid hormone production — became lower-than-normal. Also, testosterone levels remained below the normal range.
These results indicated the patient developed central adrenal insufficiency (with nearly no cortisol production), hypothyroidism (low levels of thyroid hormones) due to hypopituitarism, or deficient pituitary gland function, and hypogonadism (low levels of sex hormones).
As such, he was started on hormone replacement therapy for cortisol, thyroid hormones, and testosterone.
One month later, the man had lost 15 pounds and five inches in his waist circumference, and reported a reduction in Cushing’s physical features and symptoms. His visual defects were resolved with ophthalmology.
He is being monitored by a multidisciplinary team for disease recurrence, visual defects, and management of hypopituitarism, or deficient pituitary gland function.
“The presence of adrenal insufficiency in the setting of detectable ACTH is not contradictory as the physiological hypothalamic-pituitary-adrenal axis has been suppressed by the long-term [disease-associated] production of ACTH,” the researchers wrote.
“This report illustrates a rare case of hypercortisolism [higher-than-normal cortisol levels] remission due to apoplexy of a SGCT with subsequent central adrenal insufficiency, hypothyroidism and hypogonadism,” they wrote.
As in previous cases, this SGCT presented a larger size and reduced remission after surgery, with signs of delayed recovery of the hypothalamic-pituitary-adrenal axis.