A group of Japanese scientists has conducted a successful experiment that could help young boys with cancer one day have children despite being sterilie from cancer treatment. After freezing testicular tissue from mice, scientists were able to thaw the samples and incite them to produce sperm. 

With modern medical technology, between 70 percent and 90 percent of children with cancer survive to adulthood. However, cancer treatments often cause sterility in males. For mature men, sperm can be collected and frozen before treatment to later allow fertilization, but boys who have not yet reached puberty don't have this option. This study, led by Takehiko Ogawa of Yokohama City University's Graduate School of Medicine, could lead to a way for these boys to have children of their own later in life.

"Testis tissues of neonatal mice were cryopreserved either by slow freezing or by vitrification," says the report. "After thawing, they were cultured on agarose gel and showed spermatogenesis up to sperm formation. Microinsemination was performed with round spermatids and sperm, leading to eight offspring in total."

The offspring produced by the experiment were able to reproduce normally, and showed no signs of abnormalities. The research team believes that this technique could work for human children, easing one of the major problems caused by successful cancer treatment.

"This strategy, the cryopreservation of testis tissues followed by in vitro spermatogenesis, is promising to preserve the fertility of male paediatric cancer patients in the future," the report says.

However, translating the process to humans poses some problems. Human testicular tissue doesn't survive the same lab conditions that work for mice, so the process would have to be changed. In addition, the gel culture used to incite sperm production in the rat tissue doesn't have the same effect on that of humans. Ogawa says he is not near being able to produce human sperm.

"We have to optimize the culture conditions in each species," Ogawa says.

However, the research appears promising, and pediatric urologist Richard Yu suggests that parents of boys about to undergo cancer treatment make an effort to preserve a sample of testicular tissue.

"Research in the last few years really is encouraging that the technique will be available in the future," Yu says. "The alternative is to do nothing and your child has a high risk of sterility."