Pituitary adenoma
What is it?
Pituitary adenoma is a non-cancerous tumor that develops in the brain. This tissue growth, also known as neoplasia, is the result of cell proliferation. It is always benign, that is to say it is non-cancerous. The adenoma gets its name from the fact that it originates from the pituitary gland, a gland located at the base of the brain that controls all of our hormonal secretions.
Types of Pituitary Adenomas
Pituitary adenomas are classified under different types, depending on:
- their dimensions: if the adenomas are less than 10mm they are named micro-adenomas. Any adenomas equal to or greater than 10mm are called macro-adenomas.
- their "productivity": pituitary adenomas that are secreting (influencing hormone production) and non-secreting
Disorders Caused by Adenomas
Macro-adenomas can cause problems if the tumor mass is too large because it compresses the brain. The brain is then no longer able to secrete enough hormones. Some secretory pituitary adenomas also produce an excess of the pituitary hormone and this causes disorders such as Cushing's disease or hyperprolactinemia.
Symptoms
The symptoms of pituitary adenoma vary:
- Compression disorders of the brain, in cases of macro-adenomas, cause symptoms such as headaches and vision problems (blurred vision or loss of peripheral vision), dizziness, pain in the eyes and face, fatigue, nausea, extreme thirst and frequent urination.
- In the case of a prolactin tumor (an adenoma that produces the hormone prolactin) causes: endocrine dysfunction, including amenorrhea (interruption of the menstrual cycle in women), production of breast milk without pregnancy or childbirth, breast development in men, loss of libido, erectile dysfunction, increased weight, cardiac arrhythmia, metabolic disorders, osteoporosis, impaired blood sugar and hypertension.
If it is a growth hormone tumor it causes acromegaly (gigantism), joint pain, high sugar level, heavy perspiration, increased hair growth.
- If it is a corticotrophin (ACTH) tumor that makes too much cortisol, Cushing's disease can develop. Symptoms include weight gain (including fat between the shoulders or above the clavicles), a blushed and puffy face, increased hair growth, muscle weakness, high blood pressure and unexplained mood swings.
- If it is a thyroid stimulating tumor (TSH) that causes the thyroid to be overactive (hyperthyroidism) it causes anxiety, tremors, sleep disorders, an increased appetite but with weight loss, a feeling of warmth with a fast or irregular heartbeat and frequent bowel movements.
Treatments for Pituitary Adenoma
If you experience any of the symptoms listed above, you should consult with a health professional. There are various examinations and tests to diagnose a pituitary adenoma. First, the doctor will likely perform a hormonal assay of the blood to determine if the tumor is cerebral. Following that, it will be likely then necessary to perform an MRI to discover the characteristics of the tumor.
Medication
A pituitary adenoma cannot be eliminated through medication. However, some drugs can lead to a decrease in the size of the adenoma, or even to inhibit the excessive secretion of hormones.
Medications can also be prescribed before an operation to improve its chances of success.
Surgery
Most pituitary adenomas, whether micro or macro, secreting or not, are removed surgically, followed by radiotherapy to "clean" the area. After treatment, the patient should be checked regularly to ensure that the functionality of the pituitary gland and hormonal secretion are normal.
The operation takes place under general anesthesia and lasts between 45 minutes and one hour. The neurosurgeon can choose between two techniques for the operation:
- The "sublabial" way: an incision is made under the upper lip and above the gum so that the neurosurgeon can reach the sella turcica (a deep depression in the floor of the skull where the pituitary rests) while passing under the nose.
- The "endonasal" route: the surgeon passes through a nostril to reach the bottom of the nasal cavity and the sella turcica.
The difficulty of the surgery lies in the removal of the adenoma while not damaging the pituitary gland. In about 95% of the cases damaging the pituitary gland is avoided by observing the difference in appearance, color and consistency between the pituitary gland and the adenoma. IIf the adenoma is not very visible, a risk exists in damaging the the healthy gland or not completely removing the adenoma..
At the end of the procedure, a plug is usually placed in each nostril for two to three days in order to avoid an epistaxis (nasal bleeding) and to promote faster healing.
The operation is painless. However, patients may experience headaches above the eyes and mild nasal dryness. It is not recommended to blow your nose for a few days.
Sources: Endoscoop; French Society of Neurosurgery
Published May 16, 2019
