Updated

Scientists say it may be possible to restore sperm production in boys who are left infertile by childhood cancer treatments, BBC News reported.

One of the harmful side effects of chemotherapy and radiotherapy is that the treatments also kill cells which make sperm.  However, in a new study on monkeys, researchers from the University of Pittsburgh and the Magee-Womens Research Institute extracted sperm-producing stem cells before cancer treatment and later restored the cells.

Nine out of 12 adult monkeys and three out of five prepubescent monkeys were later able to produce healthy sperm again – meaning the sperm was capable of fertilizing female eggs.

While male cancer patients have the option of freezing sperm before treatment, this is not an option for patients who have not yet goon through puberty.

"This report is a very useful step forward and clearly shows that the science of spermatogonial stem cells transplantation might one day work for humans,” Dr. Allan Pacey, senior lecturer in andrology at the University of Sheffield, told BBC News. “And, although the authors report relatively low efficiency so far, in the context of someone who does not have any banked sperm to fall back on, these odds are probably very encouraging to make this kind of approach worthwhile."

Pacey added a main concern of the treatment was that cancer could be lurking in the stem cells, raising the possibility of re-implanting cancer cells into a healthy patient.

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