Not a Single Tumor: Hormone-Secreting and Non-Secreting
Pituitary adenomas fall most fundamentally into two groups. Hormone-secreting (functional) adenomas produce different pictures depending on the hormone: a prolactinoma can cause menstrual irregularity and milk discharge, a growth-hormone-secreting tumor can cause enlargement of the hands, feet and facial features (acromegaly), and an ACTH-secreting tumor can lead to Cushing’s disease. Non-secreting (non-functional) adenomas often stay silent for years and appear only when they grow and press on the optic nerve or surrounding structures, with symptoms such as headache and narrowing of the visual field. This distinction is very important because it directly determines the treatment path: for example, the first treatment of a prolactinoma is most often not surgery but medication.
Diagnosis: Hormones + Imaging + Eye
Diagnosis in pituitary adenoma rests on three legs. The first is hormone blood tests; which hormone is in excess or deficient determines the tumor’s type and urgency. The second is a pituitary-protocol contrast-enhanced MRI; it shows the tumor’s size and its relationship to the optic nerve and surrounding vessels. The third is a visual-field test; if the tumor is near the optic nerve, this test reveals the extent to which vision is affected. Assessing these three pieces of information together is essential — because pituitary disease is not just a “brain tumor” but also an endocrine (hormonal) disease. For this reason the assessment requires the neurosurgeon and the endocrinologist to work together.
Treatment: Medication, Surgery or Observation?
Treatment in pituitary adenoma is shaped by the tumor’s type. In a prolactinoma the first option is usually medication (dopamine agonists), and in many patients the tumor shrinks without the need for surgery. By contrast, for growth-hormone (acromegaly) or ACTH (Cushing) secreting tumors, and for large non-functional adenomas threatening vision, the first treatment is most often surgery. For small, non-secreting and asymptomatic adenomas, observation with regular MRI may be appropriate. When surgery is needed, the method preferred today is endoscopic transsphenoidal surgery: the tumor is reached directly through the nose, without opening the skull. This approach is far less invasive than open surgery, speeds recovery, and in most cases leaves no incision scar on the face or head.
How Is Endoscopic Transsphenoidal Surgery Performed?
In this operation the surgeon reaches the pituitary region directly, using a thin endoscope and instruments advanced through the nostril, passing the thin bony wall behind the nose; the skull is not opened and the brain is not retracted. It is performed under general anesthesia and usually takes a few hours depending on the tumor’s size. During the procedure the optic nerves and the large vessels nearby are protected meticulously. The hospital stay after surgery is mostly a few days, during which hormone levels and the body’s water–salt balance are closely monitored, because the hormones produced by the pituitary are known to be temporarily affected. Depending on the tumor type and the extent of removal, endocrinology follow-up and, where needed, hormone support are planned after surgery.
Expectations and Risks
In well-selected cases endoscopic pituitary surgery has a high success rate: in vision-threatening tumors vision is usually preserved or improves, and in many hormone-secreting tumors hormone levels approach normal. However, in large tumors or those adherent to surrounding tissue, complete removal may not always be possible and the chance of recurrence remains; for this reason we promise no definite result or guarantee. Possible risks include a cerebrospinal-fluid leak, hormone deficiencies (which can be permanent and are supported with medication), water–salt imbalance (diabetes insipidus) and, rarely, vision or vascular complications. These risks and the expected benefit are discussed openly with you and your endocrinologist before surgery.