For parents of young children diagnosed with cancer, looking ahead can be at once terrifying and consoling. Now, a burgeoning field of research allows those parents to consider their pre-pubescent child's ability to someday bear children — and to take steps to protect that ability.
"Survival rates for pediatric cancers are higher than ever," says reproductive endocrinologist Jani Jensen, head of the fertility preservation program at Mayo Clinic. "We hope their experience with this illness is a blip on the radar screen of a life that includes the things we all want, including the option to have children."
Of the estimated 1 in 500 children diagnosed with cancer, per year roughly 80 percent will be cured, according to the Women and Infants Hospital of Rhode Island, where a pediatric oncofertility team last year completed a fertility preservation treatment on a 17-month-old girl.
Because the aggressive methods necessary to treat certain types of cancers can cause infertility — and because pediatric patients' bodies aren't physically prepared to bear children — doctors are exploring fertility treatments that go beyond freezing eggs or freezing sperm.
"It's high-tech," Jensen says. "But it's a reality."
For pre-pubertal boys, options are "very limited," Jensen says. "Freezing pieces of testicular tissue is being done on an experimental basis."
For girls, the treatments are further along in the research process. Jared Robins, medical director of the program for fertility preservation at Women and Infants Hospital, says the procedure he performed on the 17-month-old Rhode Island girl last year is the most viable method. "The current standard is autotransplantation, which is removing ovarian tissue before it's damaged, freezing it, and transplanting it back into the intended mother when she reaches child-bearing age," he says.
The tissue can be attached to a remaining ovary, another site in the pelvis, or even other sites in the body, Jensen says, with the idea that the pieces will regain their blood supply and possibly start remaking hormones or even spontaneously growing eggs. The procedure is performed by an obstetrician/gynecologist or physician with specific training in reproductive endocrinology and infertility. Another possibility, which Jensen describes as "in the works," is to remove the immature eggs from a patient's ovary and bring them to maturation in a laboratory setting.
"All the eggs a woman will ever have, she has by the time she's born," Robins explains. "The problem is that we're not very effective at taking early eggs and developing them outside the body into mature eggs that are able to achieve ovulation and ultimately become fertilized."
Fewer than 20 young patients have undergone the fertility preservation procedures. (None of the families wanted to be interviewed for this story.) And since none of the children has reached an age at which the cryopreserved tissue can be transplanted back into her body, it's impossible to know how effective the methods will be.
"That's a psychological risk," Robins says. "We just don't know whether this is going to be functional. If they go back to use the tissue later and it doesn't work, there's a huge emotional letdown."
Physically, Robins says, the tissue removal is relatively low-risk and usually done during another oncology-related procedure.
"We like to combine them if possible, so we're not doing surgery for just the purpose of fertility preservation," Robins says. "Often a patient will need to have an abdominal procedure for a biopsy or removal of a tumor mass. Every added procedure is going to increase your risk, but it's a fairly minor procedure."
Of course, there's a chance that the child will grow into an adult who doesn't desire children of her own. That's a possibility parents have to weigh when deciding whether to dive into this still-somewhat murky territory.
"One thing I always say to people is, 'I know you're being asked to make a lot of very serious decisions, very quickly. And if it's too much to decide right now, there may be other options down the road, when this is all said and done,'" Jensen says. "But it can be very rewarding to carry and deliver a pregnancy. Culturally, we have some patients who value that above everything else."
Clinical psychologist Dan Shapiro, chairman of the Humanities Department at the Penn State College of Medicine, says the physical and emotional risks are outweighed by the potential benefits.
"Given what we know about the psychological challenges of infertility, which is enormously stressful — about as stressful as having a chronic pain condition — and the exciting promise of ovarian cryopreservation techniques, I think parents of children facing cancer treatments would be mistaken not to try this," he says. "To me, there's no dilemma here."
Shapiro has written about his own battle with cancer in his book, "Mom's Marijuana: Life, Love and Beating the Odds" (Vintage). He says parents should arm themselves with as much information as possible.
"The immediate questions to ask are the same as any involving anesthetic and very young children," he says. "Who's doing it, how long will the child be under, how much experience does the team have and how soon can we see the child? Can we accompany our child into the operating room at first?
"Parents will also want to know: Where will the tissue be stored and under what conditions, what are the safeguards for storage. At what age does the tissue become the responsibility of the child?"