title: [Prospective survey of erectile dysfunction after external beam radiotherapy for prostate cancer].
abstract: OBJECTIVE
  We prospectively evaluated the effect of external beam radiotherapy on erectile function in patients with localized or locally advanced prostate cancer using the Japanese version of the International Index of Erectile Function (IIEF) survey.
  
  
  METHODS
  From 2000 to 2007, we identified 55 patients who underwent external beam radiotherapy at our institution for localized or locally advanced prostate cancer and could respond to the IIEF survey. The patients did not receive neo- and/or adjuvant hormone therapy and they were followed-up for at least 12 months after radiotherapy. Mean patient age was 69 years and the mean PSA level before radiotherapy was 24.9 ng/ml.
  
  
  RESULTS
  First we evaluated the change of the erectile function domain score over time before and after radiotherapy. The population of severe erectile dysfunction (ED) increased while those with no or mild ED decreased after radiotherapy. The erectile function and intercourse satisfaction domain score of the IIEF declined significantly after radiotherapy, however, the orgasmic function, sexual desire, and overall satisfaction domain scores did not change after external beam radiation. Of the 34 patients who had erectile function at baseline, 10 patients could maintain erectile function 12 months after radiotherapy. Though there were no significant differences in clinical features between patients who could maintain erectile function and those who had worsening erectile function 12 months after radiotherapy, the sexual desire domain score before radiotherapy was significantly higher in patients who could maintain erectile function than their counterparts.
  
  
  CONCLUSIONS
  Using the IIEF survey, external beam radiation was found to affect erectile function in patients with localized or locally advanced prostate cancer.
authors.affiliation: Department of Urology, Keio University School of Medicine.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kikuchi
authors.forename: Jun
authors.initials: J
authors.lastname: Nakashima
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ando
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Nagata
authors.forename: Akira
authors.initials: A
authors.lastname: Miyajima
authors.forename: Ken
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Ken
authors.initials: K
authors.lastname: Marumo
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Oya
mesh_terms: D000368:Aged; D007172:Erectile Dysfunction / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects