title: Gender-related differences in prolactin secretion in pituitary prolactinomas.
abstract: In pituitary prolactinomas, serum prolactin (PRL) levels usually parallel the tumor size. We conducted a retrospective study to determine differences in PRL production between men and women with prolactinomas. A total of 51 patients, 16 men and 35 women, was studied. We investigated clinical, endocrinological, radiological and histological findings, and estimated the tumor volume (TV) by high-resolution magnetic resonance imaging (MRI). Correlation between PRL level and TV was low in men (R=0.458), in contrast to women (R=0.953), c. Men with prolactinomas showed predominance of large tumors (P=0.0009) with high PRL levels (P=0.0009) and had greater tendencies for cyst formation (P=0.0047). Large prolactinomas tended to be accompanied by cyst(s) (P=0.0051) and hemorrhage ( P=0.0015), both of which were associated with reduced PRL secretion (P=0.0004 and P<0.0001, respectively). When the volume of the cysts and hemorrhage was subtracted from the total TV, correlation between PRL level and TV became greater (R=0.905) with no gender difference. Histological examination demonstrated a sparsely granulated type of lactotroph adenoma with occasional fibrosis, particularly in tumors with hemorrhage and cysts. Although a significant discrepancy between PRL level and TV may exist in prolactinomas when intratumoral hemorrhage and/or cysts are present, there is no essential difference in PRL secretion between the sexes.
authors.affiliation: Department of Neurosurgery, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Japan. nishioka@tokyo-med.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Nishioka
authors.forename: J
authors.initials: J
authors.lastname: Haraoka
authors.forename: K
authors.initials: K
authors.lastname: Akada
authors.forename: S
authors.initials: S
authors.lastname: Azuma
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001971:Bromocriptine / Q000627:therapeutic use; D005260:Female; D006727:Hormone Antagonists / Q000627:therapeutic use; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D011388:Prolactin / Q000097:blood* / Q000187:drug effects; D015175:Prolactinoma / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D012189:Retrospective Studies; D012737:Sex Factors
chemical_list: D006727:Hormone Antagonists; D001971:Bromocriptine; D011388:Prolactin