When New Parents Get Bad News

Dr. Erik Skarsgard used minimally invasive surgery to remove Dominique Marcotte's chest tumour - photo courtesy of BC Children's Hospital Foundation
Dr. Erik Skarsgard used minimally invasive surgery to remove Dominique Marcotte’s chest tumour – photo courtesy of BC Children’s Hospital Foundation

UBC Reports | Vol. 51 | No. 11 | Nov. 3, 2005

Pediatric surgeon’s advances in fetal surgery offer new hope

By Hilary Thomson

Birth defect — two words that can chill the heart and fuel the fears of any prospective parent.

But some fears may be short-lived, thanks to the work of pediatric surgeon Dr. Erik Skarsgard, who is exploring new therapies to correct defects before baby draws its first breath.

A UBC associate professor of Surgery and Head, division of Pediatric General Surgery at Children’s and Women’s Health Centre of B.C., Skarsgard is an expert in therapies such as minimally invasive fetal surgery and fetal gene therapy.

“Advances in prenatal diagnoses have been the springboard for these new therapies,” says Skarsgard, a UBC alumnus who spent eight years on the surgical faculty at Stanford University in California before returning to Vancouver in 2001. “They offer a whole new avenue of treatment and research to repair life-threatening and complex defects.”

Of the approximately 350,000 children born in Canada every year, two to three per cent will be born with a serious congenital anomaly, according to Health Canada. Using diagnostic tools such as ultrasound, genetic testing and echocardiograms, defects are usually detected at 16-24 weeks gestation. For some fetuses with malformations of body structure, corrective surgery performed before birth may offer the only hope of survival.

In utero surgery has traditionally involved large incisions and risk of premature labour, but fetal surgeons have now adopted less risky minimal-access techniques, involving two- and three-millimetre incisions, a video-telescope and miniaturized instruments.

Skarsgard helped to develop a minimally invasive technique for fetal treatment of a condition called congenital diaphragmatic hernia (CDH). In CDH, the diaphragm fails to form properly, allowing fetal intestines and liver to move into the chest cavity, interfering with normal lung development.

However, a recent U.S. clinical trial comparing fetal to postnatal treatment of CDH showed that most fetuses are still best served by surgery performed after birth. Skarsgard stresses the importance of subjecting these new treatments to the rigour of clinical trials before they are accepted and practiced.

Another U.S. clinical study is looking at the effectiveness of fetal surgery to treat spina bifida, a defect of spinal cord development that affects one in 750 Canadian babies.

“If the spina bifida trial shows a clear benefit with fetal surgery, our fetal diagnosis and treatment group at Children’s and Women’s Hospital would be ready to set up the first fetal surgery centre in Canada,” says Skarsgard.

In addition to his work as a surgeon, Skarsgard — in collaboration with UBC neuroscientist William Jia — is the only investigator in Canada exploring fetal gene therapies.

“We’re just at the outset of research in this area,” says the 44-year-old. “But the explosion of understanding of the human genome and our ability to make early and accurate diagnoses of genetic disorders in fetuses allows us to consider a therapy such as fetal gene replacement.”

Postnatal gene therapy to replace an absent or defective gene has not been very successful because the body’s immune system reacts against vectors used to transport the replacement gene into the host. However, when replacement genes are transferred into a fetus with a genetic disorder, there is no pre-existing immunity to interfere with the transfer process.

If the idea of fetal gene replacement proves viable, it would offer new hope for genetic disorders such as cystic fibrosis, a condition that affects about one in 2,000 Caucasian births.

“We’re still at a very early stage,” says Skarsgard. “There is much we need to learn before we could ever test this treatment in humans. But it’s on the horizon as an entirely new way to treat genetic disorders.”

To enable researchers and clinicians to better understand the incidence of birth defects and effectiveness of available treatments, Skarsgard has set up a cross-Canada perinatal network that collects standardized, population-based data on fetuses and newborns.

Called the Canadian Perinatal Surgical Network (CAPSNET), the database offers information about incidence, treatment and outcomes and forms an evidence “template” that will help obstetricians, pediatricians and pediatric surgeons to develop best practice models of care for their patients.

For more information on birth defects, visit Health Canada’s web site at www.hc-sc.gc.ca.

Children’s and Women’s Health Centre of B.C. is an agency of the Provincial Health Services Authority.

CAPSNET is funded by the Canadian Institutes of Health Research, Canada’s premier health research funding agency.