title: Prostate-specific antigen decline after gonadotropin-releasing hormone antagonist withdrawal in androgen-independent prostate cancer.
abstract: A 66-year-old man with androgen-independent prostate cancer was treated with abarelix, a gonadotropin-releasing hormone antagonist, for 20 weeks in an experimental protocol. He did not respond to therapy, but his serum prostate-specific antigen level dropped from 15.8 ng/mL to a confirmed 0.8 ng/mL after abarelix was stopped. His prostate-specific antigen level did not return to greater than 15.8 ng/mL for 14 months. This is the first report of a withdrawal response after therapy with a gonadotropin-releasing hormone antagonist, a new class of agents for prostate cancer. Additional observations are needed to determine whether this is an isolated case or a harbinger of a more common phenomenon.
authors.affiliation: Division of Urology, Oregon Health & Science University, Portland, Oregon 97239, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wagner
authors.forename: Mark
authors.initials: M
authors.lastname: Garzotto
authors.forename: Dianne
authors.initials: D
authors.lastname: Lemmon
authors.forename: Kristine M
authors.initials: KM
authors.lastname: Eilers
authors.forename: Tomasz M
authors.initials: TM
authors.lastname: Beer
mesh_terms: D000368:Aged; D000728:Androgens / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D006801:Humans; D008297:Male; D009842:Oligopeptides / Q000008:administration & dosage*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000188:drug therapy* / Q000378:metabolism
chemical_list: D000728:Androgens; D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone; D017430:Prostate-Specific Antigen; C423508:abarelix