Bromocriptine treatment of prolactin secreting macroadenomas: a radiological, ophthalmological and endocrinological study.

Twelve patients, six women and six men, with macroprolactinomas characterized by extrasellar extension and basal plasma prolactin levels greater than 6 U/l were treated with 10-20 mg bromocriptine daily in four divided doses for a mean period of 2.4 years (range 0.5-3.5 years). The following observations were made: Plasma prolactin levels fell dramatically in all patients and values in the low normal range were obtained in 10 patients. Tumour size was reduced by more than 75% in 11 patients and by 50-75% in one patient. Tumour-reduction was associated with the development of a partial empty sella in eight cases. In four cases the pituitary became visible. Diminished visual acuity (three patients), bitemporal hemianopia (three patients), unilateral or bilateral central scotomas (three patients) and oculomotor palsy (two patients) restored to normal. Hypogonadism (all patients), hypothyroidism (six patients) and hypocorticism (three patients) improved or normalized in most cases. It is concluded that in the medical treatment of macroprolactinomas 10-20 mg bromocriptine in four divided doses effectively reduces both plasma prolactin level and tumour size.