title: Predictors of poor response to secondary alternative antiandrogen therapy with flutamide in metastatic castration-resistant prostate cancer.
abstract: OBJECTIVE
  In Japan, flutamide had been commonly used as second-line alternative antiandrogen hormonal therapy for metastatic castration-resistant prostate cancer that relapses after initial hormone therapy before new androgen pathway inhibitors became available. In this study, we attempted to identify predictive factors for efficacy of alternative antiandrogen as second-line hormone therapy.
  
  
  METHODS
  We identified consecutive 65 patients with metastatic castration-resistant prostate cancer who were treated with alternative antiandrogen as second-line hormonal therapy (bicalutamide to flutamide). All patients were treated with combined androgen blockade initially. We analyzed correlations between progression-free survival of alternative antiandrogen and clinicopathological characteristics, including patients' ages, initial prostate-specific antigen levels, prostate-specific antigen levels at flutamide induction, Gleason scores, T stage, N stage, extent of disease grades on bone scan and previous duration of prostate cancer response to combined androgen blockade.
  
  
  RESULTS
  In univariate analysis, T stage, N stage and previous duration of response to combined androgen blockade were correlated with shorter progression-free survival. We found four significant risk factors for shorter progression-free survival in multivariate analysis: initial prostate-specific antigen level, clinical N stage, extent of disease grades and previous duration of response to combined androgen blockade.
  
  
  CONCLUSIONS
  Initial prostate-specific antigen, N stage, extent of disease grades on bone scan and previous duration of response to combined androgen blockade were the significant predictors for efficacy of alternative antiandrogen as second-line hormone therapy in patients with metastatic castration-resistant prostate cancer. These findings might support that decision-making of when to start the new androgen receptor pathway inhibitors.
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Masato
authors.initials: M
authors.lastname: Yasui
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Koichi
authors.initials: K
authors.lastname: Uemura
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Shuko
authors.initials: S
authors.lastname: Yoneyama
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawahara
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hattori
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Teranishi
authors.affiliation: Department of Urology, Yokohama Municipal Citizen's Hospital, Yokohama.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Inoue
authors.affiliation: Department of Urology, Yokohama Municipal Citizen's Hospital, Yokohama.
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Ohta
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Yokomizo
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yao
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Hiroji
authors.initials: H
authors.lastname: Uemura
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, Yokohama.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Miyoshi
keywords: alternative antiandrogen; bone metastasis; castration-resistant prostate cancer; predictive factor; prostate cancer