title: Erectile function status is highly associated with prostate-specific antigen bounce in localized prostate cancer patients treated with permanent prostate brachytherapy.
abstract: OBJECTIVE
  To examine the relationship between erectile function status and prostate-specific antigen bounce after prostate brachytherapy for localized prostate cancer.
  
  
  METHODS
  We identified 154 patients who were followed up for at least 24 months after brachytherapy. Erectile function status was assessed prospectively before brachytherapy (baseline), and 3, 6, 12, 18, 24 and 36 months postoperatively using the International Index of Erectile Function-15 questionnaire. Prostate-specific antigen bounce was defined as an increase of at least 0.4 ng/mL from a previous prostate-specific antigen level with a subsequent decline equal to, or less than, the initial nadir without treatment. A logistic regression analysis was used to identify a significant set of independent predictors of prostate-specific antigen bounce after brachytherapy.
  
  
  RESULTS
  Prostate-specific antigen bounce was observed in 38 (24.7%) men. The prostate-specific antigen bounce group had a higher erectile function domain score, higher orgasmic function domain score, and higher total International Index of Erectile Function-15 score before (at baseline) and after brachytherapy (3, 6, 12, 18, 24 and 36 months after brachytherapy) than their counterparts (P < 0.05). Of the 77 patients who completed the International Index of Erectile Function-15 questionnaire 18 months after brachytherapy (the median time of prostate-specific antigen bounce), sexual desire and intercourse satisfaction domain scores, and total International Index of Erectile Function scores 18 months after brachytherapy correlated with the occurrence of prostate-specific antigen bounce. A multivariate analysis identified the intercourse satisfaction domain score 18 months after brachytherapy as an independent indicator for the occurrence of prostate-specific antigen bounce (P = 0.008).
  
  
  CONCLUSIONS
  International Index of Erectile Function-15 score seems to be correlated with the prostate-specific antigen bounce in prostate cancer patients undergoing brachytherapy, and an occurrence of prostate-specific antigen bounce seems to be more likely in those who are more sexually active.
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Matsushima
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kikuchi
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Kosaka
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Mizuno
authors.affiliation: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Ohashi
authors.affiliation: Department of Pathology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Mikami
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Miyajima
authors.affiliation: Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Shigematsu
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Oya
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood / Q000528:radiation effects*; D001918:Brachytherapy / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D007564:Japan; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D010410:Penile Erection; D017430:Prostate-Specific Antigen / Q000097:blood / Q000528:radiation effects*; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen
keywords: International Index of Erectile Function; brachytherapy; erectile dysfunction; prostate cancer; prostate-specific antigen bounce