title: Sperm DNA fragmentation after radioiodine treatment for differentiated thyroid cancer.
abstract: BACKGROUND
  Treatment of differentiated thyroid cancer usually consists of a total thyroidectomy followed by one or several courses of radioiodine ((131)I). (131)I is known to have deleterious effects on radiation sensitive tissues and irradiation to the testes has been shown after its administration. We investigated effects of such treatment on sperm DNA in a patient with differentiated thyroid carcinoma.
  
  
  METHODS
  The patient, a 32-year-old male with differentiated thyroid carcinoma treated by total thyroidectomy and radioiodine therapy, performed 6 semen samples in total, 3 for sperm banking and 3 for semen exploration, that were analysed for classic semen parameters. DNA integrity was analysed by flow cytometry: sperm DNA fragmentation index (DFI) and high DNA stainability (HDS) were analyzed by sperm chromatin structure assay, DNA fragmentation was analyzed by terminal deoxynucleotidyl transferase dUTP nick end labeling assay.
  
  
  RESULTS
  Moderate oligozoospermia was observed as early as 3 months after a first dose of (131)I and became severe at 5 months. Total sperm count was reduced up to 12 months after the second dose of (131)I. Sperm DFI was increased 3.25 months after the first dose of (131)I. All parameters returned to normal values 28 months after the second (131)I dose.
  
  
  CONCLUSIONS
  Treatment with (131)I induces alterations in sperm chromatin as well as in sperm parameters a short time (3 months) after a first dose of (131)I with persistence of sperm alterations until 12 months after a second dose. Sperm banking should be recommended before treatment.
authors.affiliation: Université de Toulouse, UPS, Groupe de Recherche en Fertilité Humaine (EA 3694, Human Fertility Research Group), TSA 70034, 31059, Toulouse, Cedex 9 France ; CECOS Midi-Pyrénées, Groupe d'Activité de Médecine de la Reproduction, Paule de Viguier University Hospital, Toulouse, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Esquerré-Lamare
authors.affiliation: Université de Toulouse, UPS, Groupe de Recherche en Fertilité Humaine (EA 3694, Human Fertility Research Group), TSA 70034, 31059, Toulouse, Cedex 9 France ; CECOS Midi-Pyrénées, Groupe d'Activité de Médecine de la Reproduction, Paule de Viguier University Hospital, Toulouse, France.
authors.forename: François
authors.initials: F
authors.lastname: Isus
authors.affiliation: Université de Toulouse, UPS, Groupe de Recherche en Fertilité Humaine (EA 3694, Human Fertility Research Group), TSA 70034, 31059, Toulouse, Cedex 9 France ; CECOS Midi-Pyrénées, Groupe d'Activité de Médecine de la Reproduction, Paule de Viguier University Hospital, Toulouse, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Moinard
authors.affiliation: Université de Toulouse, UPS, Groupe de Recherche en Fertilité Humaine (EA 3694, Human Fertility Research Group), TSA 70034, 31059, Toulouse, Cedex 9 France ; CECOS Midi-Pyrénées, Groupe d'Activité de Médecine de la Reproduction, Paule de Viguier University Hospital, Toulouse, France.
authors.forename: Louis
authors.initials: L
authors.lastname: Bujan
keywords: Cancer; Differentiated thyroid; Radioiodine therapy; SCSA; Semen characteristics; Sperm DNA fragmentation