GIANT PROLACTINOMAS - A RETROSPECTIVE REVIEW

During the period between January 1982 and December 1993, a total of 1 2 patients with large prolactin-secreting pituitary macroadenomas were identified, These were defined arbitrarily by a basal serum prolactin level > 1,000 ug/L in an individual showing roentgenologic evidence o f a large pituitary tumor with significant extrasellar extension, Ther e were 10 men and 2 women, with an age range from 23 to 74 years at di agnosis. The basal serum prolactin levels ranged from 1,173 to 29,180 ug/L with a mean of 6,937 ug/L (normal < 15.8 ug/L). All were hypogona dal, and all but two had visual field defects at presentation. Nine pa tients underwent pituitary surgery, 6 of whom had adjuvant external ir radiation; 3 were treated with bromocriptine alone, and all the surgic ally treated cases received additional bromocriptine therapy. Follow u p ranged from 2 to 13 years. Seven patients had serum prolactin levels of less than 40 ug/L, and 2 were in the normal range, Three patients had persistent residual visual field deficits, and all but one remaine d hypogonadal. All five patients who received external irradiation dev eloped panhypopituitarism. Two patients developed secondary resistance to bromocriptine, one of whom died of progressive disease despite agg ressive therapy.