Advances and challenges are noted in blood testing for cancer

April 15, 2014

The New York Times recently published a comprehensive article highlighting significant advances that have been made in blood testing for cancer. As alternatives to biopsy, the tests involve the detection of cancer cells or of tumor DNA fragments in serum. They could be used to provide early warning, to aid in periodic patient monitoring, and, perhaps, to enable widespread screening of healthy people.

Blood tests for cancer are not new; Janssen Diagnostics’ CellSearch, for the detection of circulating tumor cells (CTCs), was approved by the U.S. Food and Drug Administration (FDA) a decade ago. More recently, a number of other companies have been offering CTC tests or have them in development. These manufacturers include Alere, ApoCell, BioCell, Clearbridge Biomedics, Creatv MicroTech, Epic Sciences, Fluxion Biosciences, Rarecells, ScreenCell, and SRI International. Illumina, Bio-Rad Laboratories, and RainDance Technologies are positioning themselves to provide instrumentation to perform tumor DNA testing. Qiagen and Exosome Diagnostics are focusing on exosomes in the blood, and Trovagene is searching for tumor DNA fragments in urine.

Among the issues being raised about “liquid biopsies” is the question of how actionable the information they provide may be. Does the testing improve outcomes for patients? Some adherents have made the point that, if the tests provide clinicians with information that shows that therapies are ineffective and thus should be stopped, that in itself is a significant benefit. Meanwhile, researchers are seeking to refine the assays and their applications—to go beyond counting cancer cells or DNA fragments, to enable sophisticated analyses of them. Read the New York Times article.

Read more