Prenatal Blood Tests May Reveal Hidden Cancer in Expecting Mothers

Prenatal Blood Tests May Reveal Hidden Cancer in Expecting Mothers

Pregnant women often undergo blood tests to screen for fetal disorders like Down syndrome. However, in some cases, these tests can also uncover unexpected findings that may indicate the presence of a hidden cancer in the mother.

Study Findings: High Risk of Cancer in Women with Unusual Test Results

A study published in the New England Journal of Medicine examined 107 pregnant women with unusual blood test results. Shockingly, 52 of these women (48%) were subsequently diagnosed with cancer. Most of them were successfully treated and are currently in remission. However, seven women with advanced cancers succumbed to the disease. **Dr. Diana Bianchi’s Observations** Dr. Diana Bianchi, the senior author of the study, remarked, “These women appeared healthy and had no evidence of cancer on physical examination.” She emphasized the importance of taking such test results seriously and pursuing further testing, as the risk of cancer within this population is significant.

Types of Cancers Detected

The study identified the most prevalent cancers found among the diagnosed women. Lymphoma (blood cancer) was the most common, followed by colon and breast cancers.

Mechanism Behind the Discovery

The blood test employed in this study, known as cell-free DNA sequencing, is designed to detect fetal DNA fragments circulating in the mother’s bloodstream. However, it can also identify DNA fragments shed by cancer cells, providing a window into the mother’s health status.

Proportion of Women at Risk

Out of the millions of pregnant women who undergo cell-free DNA testing each year, approximately 1 in 10,000 will receive inconclusive results that warrant further investigation. This subset, comprising around 250 women annually in the United States, is at potential risk for concealed cancer.

Recommended Follow-Up: Whole-Body MRI

The study recommends that women with ambiguous test results undergo a whole-body MRI to screen for cancer. A physical exam or family history alone is insufficient, according to Dr. Bianchi.

Study Insights and Future Research

The research has identified a distinct “chaotic” pattern in the DNA sequencing of women diagnosed with cancer. Further investigations are underway to refine the criteria for identifying which pregnant women should be screened for cancer.

Current Status of Cell-Free DNA Testing

Many medical organizations advocate for cell-free DNA tests during pregnancy, but many prospective parents opt out of these optional tests. The tests are deemed reliable for detecting Down syndrome and other disorders but have been criticized for generating excessive false alarms for rare fetal conditions. **Dr. Neeta Vora’s Perspectives** Dr. Neeta Vora, director of reproductive genetics at the University of North Carolina at Chapel Hill, commented that the new finding highlights the importance of educating doctors about this potential consequence of DNA testing during pregnancy. She also acknowledged that whole-body MRIs are not routinely ordered by obstetricians and may pose a financial burden, costing between $1,000 and $2,000, potentially without health insurance coverage.