Primary treatment of macroprolactinomas with Parlodel LAR

Five patients, 3 women and 2 men, with macroprolactinomas characterized by extrasellar extension and basal plasma prolactin levels ranging from 4.6 to 102 U/l received six monthly injections of 50-100 mg Parlodel LAR, an injectable long-acting repeatable form of bromocriptine. The following observations were made: 1. Plasma prolactin levels fell dramatically in all patients and values in the normal range were obtained in 3 patients. 2. In all patients, the onset of tumour reduction was visible on CT scans made one week after the first Parlodel LAR injection. After six Parlodel LAR injections, tumour size was reduced by more than 75% in 3 patients and by 50-75% in two patients. 3. Diminished visual acuity (one patient), bitemporal hemianopia (2 patients), and oculomotor and trochlear nerve dysfunction (one patient) were restored to normal after the first Parlodel LAR injection. 4. Hypogonadism normalized in 2 patients and improved in one patient, whereas plasma gonadotropins remained low in the 2 postmenopausal women. In one patient with hypothyroidism and hypocorticism, thyroid and adrenal functions normalized. It is concluded that bromocriptine retard (50-100 mg monthly) is a useful alternative for oral treatment of patients with prolactinomas, especially in those patients with compliance problems on oral bromocriptine therapy.