Hyperprolactinemia and associated pituitary prolactinomas.

The association between serum prolactin (PRL) and the presence of pituitary tumors as determined by third generation computed tomography scan was studied in hyperprolactinemic patients. Patient charts from a four-year period were reviewed to identify those patients with elevated PRL (greater than or equal to 25 ng/mL). All patients with hyperprolactinemia underwent computed tomography scan evaluation of the pituitary gland. Hyperprolactinemia was identified in 79 patients, mean PRL 59 +/- 6.1 ng/mL SEM. Pituitary tumors were identified in 35 of these patients, mean PRL 65 +/- 11.9 ng/mL. This level was not significantly different from the level in 43 patients with normal computed tomography scans (52 +/- 5.7 ng/mL). This review found that computed tomography scan identified pituitary tumors in 44% (35 of 79) of patients with hyperprolactinemia. The likelihood of finding a pituitary tumor did not correlate with the level of hyperprolactinemia. Computed tomography scan is indicated for the diagnosis of prolactinomas in all hyperprolactinemic patients regardless of the serum PRL level.