Endocrine-inactive adenomas do not result in excess hormone production. Instead they typically cause symptoms due to pressure on the normal pituitary gland and/or on structures near the pituitary such as the optic nerves and optic chiasm.

Typical complaints of patients with an endocrine-inactive adenoma are those of hypopituitarism, vision loss and headache. Hypopituitarism may manifest itself as fatigue, decreased mental function, weight gain, lethargy, joint pains, loss of sex drive, infertility and in women, irregular periods or amenorrhea. Almost all symptomatic endocrine-inactive adenomas are macroadenomas. Occasionally, they grow quite large and into the cavernous sinus, causing nerve compression and double vision. Some patients with large tumors may have hemorrhage into the tumor (pituitary apoplexy) causing rapid onset of headache, vision loss, double vision, and/or pituitary failure.

Endocrine-inactive adenomas are diagnosed by imaging studies and hormonal testing. An MRI of the pituitary gland provides the most detail, although a brain MRI or brain CT scan will reveal most pituitary macroadenomas. Hormonal testing is also essential to evaluate for pituitary gland failure (hypopituitarism). A complete pituitary hormonal analysis should be performed as described above and is ideally overseen by an endocrinologist

Transsphenoidal Surgery:Endonasal surgery is considered the first-line treatment for symptomatic endocrine-inactive adenomas or incidentally discovered macroadenomas over 15 mm in size or those that contact the optic nerves or optic chiasm. The operation is performed through a nostril or both nostrils without facial incisions; nasal packing is not used. A fully endoscopic or endoscope-assisted approach with the microscope is used to provide high resolution and panoramic visualization during the procedure. Complete tumor removal rates are generally high (80-90%) with smaller and non-invasive tumors, and lower with larger and/or invasive tumors (30-70%). Complications such as vision loss, bleeding, stroke, cerebrospinal fluid leak and meningitis are relatively rare (1% or less) when performed by experienced endonasal transsphenoidal neurosurgeons.

The long-term surgical remission or cure rate is approximately 70-80% overall. The total tumor removal rate is higher for smaller tumors and those that do not invade the cavernous sinus; conversely, the total tumor removal rate is lower for larger tumors (over 3 cm) or those that invade the cavernous sinus. Transsphenoidal tumor removal improves visual acuity and visual field deficits in 75-90% of patients and headache resolution is seen in 80-90% of patients. Pituitary function is restored in only 20-50% of patients. Patients who do not have hormonal recovery after surgery will require hormone replacement therapy. Because the transsphenoidal approach is so effective and relatively safe, it is rare that even large macroadenomas warrant a transcranial operation as the initial procedure. 

Medical therapy: There is no effective medical therapy that reliably halts growth of endocrine-inactive adenomas.

Radiosurgery (SRS) or Stereotactic Radiotherapy (SRT):For patients who have residual tumor after the initial transsphenoidal surgery, focused radiation with SRT or SRS may be needed to control tumor growth. Both SRT and SRS halt tumor growth in at least 85-90% of patients. However, SRT and SRS may result in loss of normal pituitary function over 5 to 10 years. Neurologic complications such as visual loss and temporal lobe damage rarely occur with SRT and SRS.