"Young men undergoing treatment for cancer often want to know how the disease and its treatment affect their chances of fathering healthy children. Our large-scale study shows that there is a slightly higher risk of deformities, but the actual risk of having a child with deformities is nevertheless extremely low. I think this is good news!"
These words are from the cancer physician Olof Stahl, who has studied this issue in his coming dissertation from Lund University in Sweden.
It is known that undergoing radiation treatment and chemotherapy can affect male fertility. For this reason, attempts are always made nowadays to preserve and freeze sperm before cancer treatment starts. Just how fertility is affected then depends on the type of cancer and the type of treatment. The result can be anything from unaffected sperm production to complete loss of sperm production, with a middle group where production is impacted in a way that leaves fewer sperms with impaired mobility.
The question of possible connections between cancer and the risk of deformities in future children has been less thoroughly addressed. Can cancer have affected the sperms even though sperm production as such is entirely normal? And in cases requiring in vitro fertilization, IVF, is there a risk of using sperms that need help carrying out fertilization but also are bearing damaged genes? These issues have never been studied before.