title: Sperm preservation and neutron contamination following proton therapy for prostate cancer study.
abstract: BACKGROUND
  The present study investigates the impact of scatter dose radiation to the testis on ejaculate and sperm counts from treatment of prostate cancer with passive-scatter proton therapy.
  
  
  METHODS
  From March 2010 to November 2014, 20 men with low- or intermediate-risk prostate cancer enrolled in an IRB-approved protocol and provided a semen sample prior to passive-scatter proton therapy and 6-12 months following treatment. Men were excluded if they had high-risk prostate cancer, received androgen deprivation therapy, were on alpha blockers (due to retrograde ejaculation) prior to treatment, had baseline sperm count <1 million, or were unable to produce a pre-treatment sample or could not provide a follow-up specimen. Sperm counts of 0 were considered azoospermia and <15 million/ml were classified as oligospermia.
  
  
  RESULTS
  Four patients were unable to provide a sufficient quantity of semen for analysis. Among the 16 remaining patients, only one was found to have oligospermia (7 million/ml). There was a statistically significant reduction in semen volume (median, 0.5 ml) and increase in pH (median 0.5). Although not statistically significant, there appeared to be a decline in sperm concentration (median, 16 million/ml), total sperm count (median, 98.5 million), normal morphology (median, 9%), and rapid progressive motility (median, 9.5%).
  
  
  CONCLUSIONS
  Men did not have azoospermia 6-12 months following passive-scatter proton therapy indicating minimal scatter radiation to the testis during treatment. Changes in semen quantity and consistency may occur due to prostate irradiation, which could impact future fertility and/or sexual activity.
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Bradford S
authors.initials: BS
authors.lastname: Hoppe
authors.affiliation: b The Department of Surgery, Division of Urology , University of Florida College of Medicine , Jacksonville , FL , USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Harris
authors.affiliation: c The Department of Obstetrics and Gynecology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Alice
authors.initials: A
authors.lastname: Rhoton-Vlasak
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Curtis
authors.initials: C
authors.lastname: Bryant
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Morris
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Roi
authors.initials: R
authors.lastname: Dagan
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Romaine C
authors.initials: RC
authors.lastname: Nichols
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: William M
authors.initials: WM
authors.lastname: Mendenhall
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Randal H
authors.initials: RH
authors.lastname: Henderson
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Zuofeng
authors.initials: Z
authors.lastname: Li
authors.affiliation: a The Department of Radiation Oncology , University of Florida College of Medicine , Gainesville , FL , USA.
authors.forename: Nancy P
authors.initials: NP
authors.lastname: Mendenhall
mesh_terms: D000368:Aged; D005298:Fertility / Q000528:radiation effects*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D009502:Neutrons; D011379:Prognosis; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D061766:Proton Therapy; D012662:Semen Preservation; D013091:Spermatogenesis / Q000528:radiation effects*