Stories have been circulating for a while now that anomalous non-invasive prenatal genetic screening (NIPGS) results may sometimes indicate maternal cancer. Recently, however, these anecdotes have given way to more rigorous data, from a group of researchers at University of Leuven in Belgium, and from US companies Sequenom and Illumina.

For many this new discovery is not all that surprising. For several years now, researchers have been pursuing a test, based on cell-free DNA, that would provide a reliable “liquid biopsy.” Indeed, such tests are already being used clinically in limited circumstances, though–as with NIPGS–the rapid translation of this technology has left important questions about reliability and actionability as yet unanswered. Even more promising, sequencing cell-free DNA may circumvent some of the problems recently proposed with sequencing tumor DNA without matched controls from normal tissue–because both kinds of DNA will be present in serum, and can be distinguished by their relative frequency, much as NIPGS does with fetal and maternal cell-free DNA. Continue reading How do we deal with NIPGS and ‘The Big C’?