If you knew you had a gene mutation that confers a high risk of cancer, would you use IVF and preimplantation genetic diagnosis (PGD) to prevent passing on the mutation to your offspring?
That is the question that cancer doctors at MD Anderson Cancer Center in Houston put to 155 young women, still of childbearing potential, with breast cancer. The doctors actually asked their patients a number of questions related to childbearing after their cancer diagnosis; I’m focusing here on the PGD question.
As you read on, keep in mind that the majority of patients would have been Texans—that is, residents of a “conservative” state.
Infertility is a serious complication of treating cancer in young people. For decades, sperm banking has been an option for young males with cancer who might want to conceive in the future. Various technical advances in assisted reproduction technology (ART), including oocyte cryopreservation (freezing eggs), have opened up options for young females whose cancer therapy impairs if not frankly eliminates their ability to ovulate. To be sure, these options generally require in vitro fertilization (IVF), be it with a woman’s own or donated eggs.
While there are several ethical issues related to childbearing after cancer treatment, the researchers in this case were concerned about the patients’ attitudes, and whether those were affected by learning, from a genetic test, whether they carried cancer-susceptibility mutations in the “BRCA” genes. For my purposes here, the upshot:
- About 1 in 4 women said they were likely to pursue PGD or prenatal diagnosis (PND, through amniocentesis or chorionic villus sampling) as part of their decision-making.
- Knowing the results of the genetic testing didn’t change that number much at all.
- Perhaps a slightly higher number of the women—closer to 30%–would consider PND rather than PGD.
- About 2 in 5 said they would be unlikely to pursue PGD or PND.
- About 1 in 3 were undecided.
- About 80% thought that, irrespective of their own personal preference, PGD and PND ought to be available to families with BRCA gene mutations or other inherited cancer syndromes.
I read this as fairly widespread acceptance of PGD or PND to prevent the birth of some children with cancer-susceptibility gene mutations. Surely no one desires to pass on significant risk of serious disease to his or her progeny, but I find the acceptance of PGD or PND troubling nonetheless. If you accept that PGD may be used in limited cases, to prevent the birth of infants with devastating disease, where do you draw the line? Where will societal, economic, and government pressures draw the line? And does making PGD and PND “available” mean that others have a duty to support it? Is there a place for religious exceptions? All standard questions, to be sure.
The study in question was published in the August 2014 issue of The Oncologist. It can be accessed free online (registration required) here.