Projects we fund

Overview

Childhood cancer rates have increased over recent decades and remarkable improvements in cure rate has resulted in an increase in young adults experiencing subsequent health effects of their cancer treatment. Ensuring long-term health of this new and expanding patient cohort is one of the most pressing areas of clinical need in paediatric oncology. Infertility occurs in the majority of males receiving high-dose chemotherapy with drugs known as alkylating agents, which are commonly used in childhood cancer. Unlike the situation in men, cryopreservation of sperm is not an option to preserve fertility in these boys as their testicles are not capable of making sperm in childhood. As a result, there is currently no established clinical option to prevent infertility in prepubertal boys receiving chemotherapy. Preservation of fertility in children receiving cancer treatment is dependent on survival of the spermatogonial stem cells (SSC) in the testicle. These stem cells will generate sperm in males after puberty. We are currently able to cryopreserve testicular tissue, containing SSCs, from boys before they receive cancer treatment. Establishing this fertility preservation programme was supported by funding from Children with Cancer UK. This tissue is available for future use to restore fertility in these patients in adulthood. Transplantation of the tissue back to the patient represents a good potential option to restore fertility in these patients and this has proved to be successful in primate studies. However, transplantation has not been performed in humans yet.

Professor Rod Mitchell and his team aim to restore fertility in male patients who have had childhood cancer treatment that has made them infertile. The aim of this project is to undertake the first clinical trial to transplant testicular tissue to restore fertility in patients who had their tissue cryopreserved in childhood. The project will involve developing a safe and effective protocol to conduct the transplants, in addition to obtaining the necessary ethics and regulatory approvals. The project will undertake the transplants in carefully selected cases. Once the transplanted tissue has begun to produce sperm, these will be extracted and stored or used to make embryos if the patient wants to have a child at the time. This would represent an important breakthrough to enable young people treated for cancer during childhood to have children of their own.

What difference will this project make?

This project will, for the first time, prove that fertility potential can be restored in patients who would otherwise be unable to have their own biological children. Successful completion of the project will potentially open the door to future fertility for greater than 800 patients in the UK (greater than 2500 worldwide) who have had testicular tissue stored for fertility preservation, as well as providing an option for all future patients due to receive childhood cancer treatment that can impair their fertility. This would represent a major step for improving the quality of life for survivors of childhood cancer.