Spermatogonial quantity in human prepubertal testicular tissue collected for fertility preservation prior to potentially sterilizing therapy

• Published in: Human Reproduction
• Main Authors: Stukenborg, J. B., Alves-Lopes, J. P., Kurek, M., Albalushi, H., Reda, A., Keros, V., Töhönen, V., Bjarnason, R., Romerius, P., Sundin, M., Nyström, U. Norén, Langenskiöld, C., Vogt, H., Henningsohn, L., Mitchell, R. T., Söder, O., Petersen, C., Jahnukainen, K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press 2018
• Subjects: Obstetrics; Gynecology and Reproductive Medicine; alkylating agents; childhood cancer; Fertility preservation; sickle cell disease; spermatogonial quantity; Iceland
• Online Access: https://lup.lub.lu.se/record/21188093-8fad-4bb2-bd75-7542c5115496; https://doi.org/10.1093/humrep/dey240

STUDY QUESTION: Does chemotherapy exposure (with or without alkylating agents) or primary diagnosis affect spermatogonial quantity in human prepubertal testicular tissue? SUMMARY ANSWER: Spermatogonial quantity is significantly reduced in testes of prepubertal boys treated with alkylating agent therapies or with hydroxyurea for sickle cell disease. WHAT IS KNOWN ALREADY: Cryopreservation of spermatogonial stem cells, followed by transplantation into the testis after treatment, is a proposed clinical option for fertility restoration in children. The key clinical consideration behind this approach is a sufficient quantity of healthy cryopreserved spermatogonia. However, since most boys with malignancies start therapy with agents that are not potentially sterilizing, they will have already received some chemotherapy before testicular tissue cryopreservation is considered. STUDY DESIGN, SIZE, DURATION: We examined histological sections of prepubertal testicular tissue to elucidate whether chemotherapy exposure or primary diagnosis affects spermatogonial quantity. Quantity of spermatogonia per transverse tubular cross-section (S/T) was assessed in relation to treatment characteristics and normative reference values in histological sections of paraffin embedded testicular tissue samples collected from 32 consecutive boy patients (aged 6.3 ± 3.8 [mean ± SD] years) between 2014 and 2017, as part of the NORDFERTIL study, and in 14 control samples (from boys aged 5.6 ± 5.0 [mean ± SD] years) from an internal biobank. PARTICIPANTS/MATERIALS, SETTING, METHODS: Prepubertal boys in Sweden, Finland and Iceland who were facing treatments associated with a very high risk of infertility, were offered the experimental procedure of testicular cryopreservation. Exclusion criteria were testicular volumes >10 ml and high bleeding or infection risk. There were 18 patients with a diagnosis of malignancy and 14 patients a nonmalignant diagnosis. While 20 patients had the testicular biopsy performed 1-45 days after chemotherapy, 12 ...