Hyperprolactinaemia in males with and without pituitary macroadenomas.

To ascertain whether in hyperprolactinaemic men pituitary macroadenomas represent the end stage of a disease process wherein the only early symptom is impotence, the features of 16 hyperprolactinaemic men with radiological evidence of pituitary macroadenomas were compared with those of 10 hyperprolactinaemic men without pituitary macroadenomas. All were impotent and 25 had low serum testosterone levels. The group with pituitary macroadenoma was older (48.1 vs 63.2 years) and had tolerated impotence for longer (10.4 +/- 6.0 vs 4.5 +/- 2.1 years). 6 of them had visual field defects (none in the other group), 14 had hypopituitarism (1 in the other group), and 14 were initially seen for problems other than sexual dysfunction (whereas all 10 without pituitary macroadenomas were seen primarily for evaluation of recent onset of impotence). In the macroadenoma group bromocriptine restored serum prolactin levels in 13 of the 16 and serum testosterone and potency in 5, whereas in the non-tumour group it restored serum prolactin levels in all 10 and serum testosterone and potency in 9.