Research looks at fertility for male childhood cancer survivors

While children with cancer are likely to survive, there can be lifelong health impacts from treatment – particularly infertility. But new research may have found a way to restore male fertility.

By Re: News’ Baz Macdonald

Every year 400,000 young people aged 0 to 19 are diagnosed with cancer around the world.

Around 300 of those are in Aotearoa.

More than 80% of children diagnosed with cancer are cured and about 1 in 900 people between 16 and 34 in Aotearoa are childhood cancer survivors.

However cancer treatments can have lifelong health impacts for those survivors, particularly when it comes to fertility.

Research from the United States shows that male survivors are 44% less likely to have a child compared to their siblings who did not have cancer treatments. Female survivors are 19% less likely.

Research manager at the Blood and Cancer Centre from Auckland’s Starship Hospital Dr Sarah Hunter said for boys who have gone through puberty it is possible to store sperm for future use before treatments.

Fertility preservation isn’t possible for people who haven’t gone through puberty.

People with uteruses are born with their lifetime supply of eggs, Hunter said, but before puberty these eggs have not matured and can’t be stored.

Cancer treatments can damage these eggs and make people unable to conceive or carry a pregnancy.

These treatments can also damage sperm and sperm production.

But a study published in May from the University of Pennsylvania may have found a way to help address infertility in males.

Researchers extracted functional tissue from the testes of mice and froze it for 23 years.

The tissue was then implanted into an infertile mouse who began producing functional sperm.

Although there was reduced fertility, the study said this could represent a significant advancement in the treatment of infertility, especially for children with cancer where healthy tissue could be secured before receiving treatment.

Hunter said this study is part of extensive international research happening on fertility preservation for childhood cancer survivors.

“The freezing and storage of testicular tissue for that child’s own use in adulthood is a process that offers the chance of fertility later in life,” Hunter said.

“This is very early technology around the world and while testicular tissue has now been stored for about 1000 pre-pubertal males internationally, there have been no reports of human pregnancies or babies that have resulted from the use of banked tissue.”

Hunter and her colleagues are currently developing the process for storing testicular tissue of prepubescent boys in Aotearoa.

Research into ovarian tissue storage is also ongoing.