title: Withdrawal of bromocriptine after long-term therapy for macroprolactinomas; effect on plasma prolactin and tumour size.
abstract: The present study describes the effect on plasma prolactin values and tumour size of bromocriptine withdrawal in 12 patients who had been treated for macroprolactinomas for a period of 3.5-7 (mean 4.9) years. Pretreatment plasma prolactin values ranged from 12,000 to 210,000 (mean: 66,000) mU/l. Immediately before bromocriptine withdrawal plasma prolactin values were in the normal range (less than 350 mU/l for men; less than 450 mU/l for women). Bromocriptine treatment was associated with tumour reduction in all cases. The following observations were made upon withdrawal of bromocriptine: (1) In 11 patients hyperprolactinaemia redeveloped although plasma prolactin levels remained below 600 mU/l in two of these patients during a follow-up period of 1 year. In the other nine patients bromocriptine treatment was reinstituted after 4-12 weeks. (2) Hyperprolactinaemia was associated with tumour reexpansion in one case and increased density of the tumour in two cases. (3) In one patient plasma prolactin remained undetectable during a follow-up period of 1 year and no tumour re-expansion was found. It is concluded that tumour regrowth is uncommon and of small extent after cessation of long-term bromocriptine treatment for macroprolactinomas.
authors.affiliation: Department of Neurosurgery, Rudolf Magnus Institute, Academic Hospital, Medical Faculty, Utrecht, The Netherlands.
authors.forename: J W
authors.initials: JW
authors.lastname: van 't Verlaat
authors.forename: R J
authors.initials: RJ
authors.lastname: Croughs
mesh_terms: D000328:Adult; D000368:Aged; D001971:Bromocriptine / Q000008:administration & dosage* / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D011388:Prolactin / Q000097:blood*; D015175:Prolactinoma / Q000097:blood / Q000188:drug therapy* / Q000473:pathology
chemical_list: D001971:Bromocriptine; D011388:Prolactin