title: Should We Try Antiandrogen Withdrawal in Castration-Resistant Prostate Cancer Patients? Insights From a Retrospective Study.
abstract: It remains uncertain whether those with response to antiandrogen withdrawal (AAW) have a better prognosis. We investigated the predictors of a better response to AAW and overall survival after acquiring resistance to first-line androgen deprivation therapy inpatients with castration-resistant prostate cancer (CRPC).
  
  
  
  We retrospectively reviewed the medical records of 87 CRPC patients treated at Keio University Hospital. Sixty-seven of 87 CRPC patients underwent AAW. We analyzed clinicopathologic parameters to identify predictors of survival in CRPC patients and investigated predictors of good response to AAW.
  
  
  
  Younger age, longer duration of androgen deprivation therapy before CRPC development, and better response to AAW were independent favorable prognostic factors for overall survival. Although better response to AAW was a favorable prognostic factor in this study, trying AAW was not significantly related to overall survival. Duration of hormone therapy was significantly longer in those whose disease responded to AAW (69.9 ± 11.0 months) than those with no response (45.3 ± 5.2 months).
  
  
  
  The prognostic benefit of AAW was not clearly determined in this study. However, AAW might be beneficial in patients who have favorable prognostic factors for a response to AAW-that is, those who have received hormone therapy for a long period. However, AAW should not be done in patients who do not have favorable factors and who had a high prostate-specific antigen level at the time of their prostate cancer diagnosis.
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hongo
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan. Electronic address: takemduro@gmail.com.
authors.forename: Takeo
authors.initials: T
authors.lastname: Kosaka
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Mizuno
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Ezaki
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Morita
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Shinoda
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shinojima
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kikuchi
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Miyajima
authors.affiliation: Keio University School of Medicine, Shinjuku-ku, Japan.
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Oya
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000008:administration & dosage* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D011379:Prognosis; D017430:Prostate-Specific Antigen; D064129:Prostatic Neoplasms, Castration-Resistant / Q000188:drug therapy*; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D017430:Prostate-Specific Antigen
keywords: Androgen deprivation therapy; Antiandrogen withdrawal syndrome; Hormone therapy; Nonsteroidal antiandrogens; Prostate-specific antigen