title: Estrogen-induced prolactinoma in a man.
abstract: Prolactinomas can be induced in rats by large doses of estrogens. Whether prolactinomas can be induced in humans by estrogens, however, is not known. This report describes the development of a prolactinoma in a man with previously normal plasma PRL levels after the administration of pharmacological doses of estrogen. The patient, a 26-yr-old male to female transsexual, took cyproterone acetate (100 mg/day, orally) and ethinyl estradiol (100 micrograms/day, orally) for 10 months and (surrepititiously) estradiol-17-undecanoate (100 mg, twice weekly, im) for about 6 of the 10 months. Plasma PRL levels rose from 0.05 to 5.20 U/L within 10 months (normal, 0.05-0.30 U/L). A computed tomographic scan showed a pituitary mass with suprasellar extension. After all estrogen therapy was discontinued, his plasma estradiol levels gradually declined from 2.8 to 0.77 nmol/L (normal, 0.04-0.12 nmol/L), but PRL levels rose further to 6.2 U/L. Bromocriptine treatment (2.5 mg twice daily) then was given. Plasma PRL fell gradually to 0.43 U/L and a computed tomographic scan after 5 months showed reduction in tumor size. The patient then discontinued bromocriptine treatment. Four months later his plasma estradiol level was normal, while plasma PRL had risen to 4.6 U/L, indicating autonomous PRL secretion. We conclude that 1) estrogen in pharmacological doses can induce prolactinomas in man; and 2) subjects treated with high doses of estrogen must, therefore, be surveyed for the development of such tumors.
authors.affiliation: Department of Endocrinology/Andrology, Academic Hospital Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: L J
authors.initials: LJ
authors.lastname: Gooren
authors.forename: J
authors.initials: J
authors.lastname: Assies
authors.forename: H
authors.initials: H
authors.lastname: Asscheman
authors.forename: R
authors.initials: R
authors.lastname: de Slegte
authors.forename: H
authors.initials: H
authors.lastname: van Kessel
mesh_terms: D000328:Adult; D001971:Bromocriptine / Q000627:therapeutic use; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000009:adverse effects*; D006801:Humans; D008297:Male; D010902:Pituitary Gland / Q000473:pathology; D010911:Pituitary Neoplasms / Q000139:chemically induced* / Q000188:drug therapy; D011388:Prolactin / Q000097:blood / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D014189:Transsexualism / Q000150:complications*
chemical_list: D004967:Estrogens; D001971:Bromocriptine; D004958:Estradiol; D011388:Prolactin