The exact cause is unknown, but a predisposition to a pituitary tumor may be inherited through an autosomal dominant trait. A pituitary tumor isn’t malignant in the strict sense; however, its invasive growth categorizes it as a neoplastic condition.

Chromophobe adenoma may be associated with the production of corticotropin, melanocyte-stimulating hormone, growth hormone, and prolactin; basophil adenoma, with excess corticotropin production and consequently Cushing’s syndrome; and eosinophil adenoma, with excessive growth hormone.

The loss of pituitary hormone action results in endocrine abnormalities throughout the body if lost hormones aren’t replaced. Tumor compression of the hypothalamus may result in diabetes insipidus.

The patient’s history may reveal complaints related to neurologic and endocrine abnormalities. Typically, the patient complains of a frontal headache and visual disturbances (blurred vision progressing to field cuts and eventually blindness). The patient’s family may describe personality changes or dementia. The patient may also report amenorrhea, decreased libido, impotence, lethargy, weakness, increased fatigability, sensitivity to cold, constipation (from decreased production of corticotropin and thyroid-stimulating hormone), and seizures.

Inspection may reveal rhinorrhea, a sign that the tumor has eroded the base of the skull. History and inspection may reveal cranial nerve (III, IV, VI) involvement from lateral extension of the tumor. With cranial nerve involvement, the patient typically reports diplopia and dizziness. You may observe head tilting to compensate for diplopia, conjugate deviation of gaze, nystagmus, eyelid ptosis, and limited eye movements.

Inspection may also disclose skin changes that indicate endocrine involvement. Examples include a waxy appearance, fewer wrinkles (which the patient may report during the history), and pubic and axillary hair loss.

Inspection of the eyes may reveal strabismus.