Many mothers opt for a blood test pregnancy To check for fetal disorders such as Down syndrome. In rare cases, these tests can reveal something unexpected – a sign of hidden cancer in a woman.
In a study of 107 pregnant women whose test results were abnormal, 52 were eventually diagnosed with cancer. Most of them were treated and are now in remission, although seven with advanced cancer died.
“They looked healthy, young women And they reported themselves to be healthier,” said Dr. Diana Bianchi, senior author of the government study published Wednesday. New England Journal of Medicine.
Among the cancers diagnosed, lymphoma and blood cancers were the most common, followed by colon and breast cancers.
A blood test called cell-free DNA sequencing. It looks for fetal problems in fragments of DNA that pass from the placenta into the mother’s blood. It can also pick up DNA fragments shed by cancer cells.
Of the millions of pregnant women who have cell-free DNA testing each year, 1 in 10,000 will get a result that is abnormal and difficult to interpret, neither positive nor negative for a fetal abnormality. A small number of people—perhaps as few as 250 per year in the United States—may be at risk for cancer.
“They and their care providers should take the results seriously and do more testing because that population has a 48% risk of cancer,” said Bianchi, who leads the National Institute of Child Health and Human Development.
The study looked at what should be done next, and the researchers concluded that a whole-body MRI is best to look for cancer. A physical exam or taking a family history isn’t enough, Bianchi said.
About five years ago, commercial labs and doctors who performed these tests began telling women with abnormal results about the study. The National Institutes of Health paid for study volunteers to travel to its research hospital in Bethesda, Maryland, where participants underwent a review of their family and medical history, a complete physical exam, whole-body MRI scans and other tests.
Another reason why screening tests are needed (Source: Pixabay)
The research identified a “very chaotic” pattern recognizable in the DNA sequences of women diagnosed with cancer, Bianchi said. Studies continue to find more evidence to indicate who should be screened for cancer.
Many medical groups now recommend offering cell-free DNA testing during pregnancy, even though many expectant parents decide against the alternative test. Considered reliable for detecting Down syndrome and two other disorders, the tests have come under scrutiny for many false alarms for extremely rare fetal problems.
The new discovery will help educate doctors about the rare results of DNA testing during pregnancy, said Dr. Neeta Vora said.
Doctors who care for pregnant women aren’t used to ordering whole-body MRI exams, Vora said, and these scans, which can cost $1,000 to $2,000, may not be covered by health insurance.