title: A European perspective on testicular tissue cryopreservation for fertility preservation in prepubertal and adolescent boys.
abstract: OBJECTIVE
  What clinical practices, patient management strategies and experimental methods are currently being used to preserve and restore the fertility of prepubertal boys and adolescent males?
  
  
  CONCLUSIONS
  Based on a review of the clinical literature and research evidence for sperm freezing and testicular tissue cryopreservation, and after consideration of the relevant ethical and legal challenges, an algorithm for the cryopreservation of sperm and testicular tissue is proposed for prepubertal boys and adolescent males at high risk of fertility loss.
  
  
  BACKGROUND
  A known late effect of the chemotherapy agents and radiation exposure regimes used to treat childhood cancers and other non-malignant conditions in males is the damage and/or loss of the proliferating spermatogonial stem cells in the testis. Cryopreservation of spermatozoa is the first line treatment for fertility preservation in adolescent males. Where sperm retrieval is impossible, such as in prepubertal boys, or it is unfeasible in adolescents prior to the onset of ablative therapies, alternative experimental treatments such as testicular tissue cryopreservation and the harvesting and banking of isolated spermatogonial stem cells can now be proposed as viable means of preserving fertility.
  
  
  METHODS
  Advances in clinical treatments, patient management strategies and the research methods used to preserve sperm and testicular tissue for prepubertal boys and adolescents were reviewed. A snapshot of the up-take of testis cryopreservation as a means to preserve the fertility of young males prior to December 2012 was provided using a questionnaire.
  
  
  METHODS
  A comprehensive literature review was conducted. In addition, survey results of testis freezing practices in young patients were collated from 24 European centres and Israeli University Hospitals.
  
  
  RESULTS
  There is increasing evidence of the use of testicular tissue cryopreservation as a means to preserve the fertility of pre- and peri-pubertal boys of up to 16 year-old. The survey results indicate that of the 14 respondents, half of the centres were actively offering testis tissue cryobanking as a means of safeguarding the future fertility of boys and adolescents as more than 260 young patients (age range less than 1 year old to 16 years of age), had already undergone testicular tissue retrieval and storage for fertility preservation. The remaining centres were considering the implementation of a tissue-based fertility preservation programme for boys undergoing oncological treatments.
  
  
  CONCLUSIONS
  The data collected were limited by the scope of the questionnaire, the geographical range of the survey area, and the small number of respondents.
  
  
  CONCLUSIONS
  The clinical and research questions identified and the ethical and legal issues raised are highly relevant to the multi-disciplinary teams developing treatment strategies to preserve the fertility of prepubertal and adolescent boys who have a high risk of fertility loss due to ablative interventions, trauma or genetic pre-disposition.
authors.affiliation: Division of Reproduction and Early Development, Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Clarendon Way, Leeds LS2 9JT, UK h.m.picton@leeds.ac.uk.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Picton
authors.affiliation: Université Catholique de Louvain (UCL), Pôle de Recherche en Gynécologie, Institut de Recherche Expérimentale et Clinique (IREC), 1200 Brussels, Belgium Department of Gynecology-Andrology, Cliniques Universitaires Saint-Luc, Avenue Hippocrate, 10, 1200 Brussels, Belgium.
authors.forename: Christine
authors.initials: C
authors.lastname: Wyns
authors.affiliation: MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Anderson
authors.affiliation: Research Group Biology of the Testis (BITE), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium.
authors.forename: Ellen
authors.initials: E
authors.lastname: Goossens
authors.affiliation: Children's Hospital, Helsinki University Central Hospital, Helsinki, Finland Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden.
authors.forename: Kirsi
authors.initials: K
authors.lastname: Jahnukainen
authors.affiliation: Centre of Reproductive Medicine and Andrology, University Münster, Domagkstraße 11, 48149 Münster, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kliesch
authors.affiliation: MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK.
authors.forename: Rod T
authors.initials: RT
authors.lastname: Mitchell
authors.affiliation: Bioethics Institute Ghent (BIG), Faculty of Philosophy and Moral Science, Ghent University, Ghent, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Pennings
authors.affiliation: Laboratoire de Biologie de la Reproduction - CECOS, Research Team EA 4308 'Gametogenesis and gamete quality', IRIB, Rouen University Hospital, University of Rouen, 76031 Rouen Cedex, France.
authors.forename: Natalie
authors.initials: N
authors.lastname: Rives
authors.affiliation: Centre for Reproductive Medicine, University Hospital of the Brussels Free University, Laarbeeklaan 101, 1090 Brussels, Belgium.
authors.forename: Herman
authors.initials: H
authors.lastname: Tournaye
authors.affiliation: Center for Reproductive Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Ans M M
authors.initials: AM
authors.lastname: van Pelt
authors.affiliation: Faculty of Biology, Gene Technology/Microbiology, University of Bielefeld, Bielefeld 33501, Germany.
authors.forename: Ursula
authors.initials: U
authors.lastname: Eichenlaub-Ritter
authors.affiliation: Centre of Reproductive Medicine and Andrology, University Münster, Domagkstraße 11, 48149 Münster, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schlatt
mesh_terms: D000293:Adolescent; D002648:Child; D015925:Cryopreservation / Q000379:methods*; D005060:Europe; D059247:Fertility Preservation / Q000379:methods*; D006801:Humans; D008297:Male; D013737:Testis
keywords: adolescents; boys; cryopreservation; fertility preservation; spermatogonial stem cell; testis