Dr. Orwig began by highlighting the role of fertility preservation in cancer patients. It is well recognized that many cancer treatments can cause permanent infertility. While adult men and women can cryopreserve eggs, sperm, or embryos before treatment for future pregnancies, these options are not available to pre-pubertal patients.
Currently, many centers worldwide are preserving testicular tissue in boys and ovarian tissue in girls in to hope that future medical technology interventions will be available for new reproductive technologies in the future. Highlighting their experience in Pittsburgh, Dr. Orwig highlighted that, since 2011, they have cryopreserved testicular tissue in 316 boys and ovarian tissue in 70 girls.
These samples undergo a controlled rate of slow freezing under sterile conditions.
Moving forward, there are potentially a number of opportunities to utilize the preserved tissue for fertility preservation including the transplantation of tissue to allow for natural insemination and the recovery of sperm (either from autologous grafting or xenografting) for using in artificial reproductive techniques such as intracytoplasmic sperm injection (ICSI).
Current work in primates is working to refine methods for autologous grafting of prepubertal testis tissue following cryogenic storage and chemotherapy in Rhesus monkey models. To date, a number of graft sites and techniques.
Initial data, using an assessment of testosterone levels, demonstrates the viability and functionality of this grafted testicular tissue. Further, the transplanted testicular tissue demonstrates growth and maturation over time.
Following harvest, histologic analysis of the autologous grafts demonstrated complete spermatogenesis. Harvest of sperm from this testicular tissue allows for ICSI with embryo transfer and successful confirmation of pregnancy with the delivery of a Rhesus monkey baby.
Presented by: Kyle Orwig, PhD, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
Written by: Christopher J.D. Wallis, Urologic Oncology Fellow, Vanderbilt University Medical Center, Nashville, TN, USA, Twitter: @WallisCJD, at the Virtual 2020 EAU Annual Meeting #EAU20, July 17-19, 2020.