A blood sample found cancer-causing mutations more than a tumor biopsy, delegates to the American Association for Cancer Research, meeting in Washington, were told.
"Samples from tumors may not reveal all underlying mutations." The screen, called BEAMING technology, is sensitive enough to detect rare mutations in the bloodstream, in the form of free DNA, genetic material shed from tumors.
Harvard Med School's Ludwig Center at the Dana-Farber Cancer Institute's findings could become a standard part of caring for cancer patients. The analysis was done as a part of Leverkusen, Germany-based Bayer's trial of Stivarga, a cancer therapy approved in February for gastrointestinal stromal tumors and last year for colorectal cancer.
Stivarga is approved for use in gastrointestinal stromal tumors after patients' cancer has stopped responding to Sutent and Gleevec. Bayer promotes Stivarga with Onyx Pharmaceuticals.
In the study, researchers took blood samples when patients' cancer had progressed and analyzed them for mutations, including secondary mutations in 48 percent of blood samples, versus 12 percent of tissue samples.
Newer versions of the technology are being worked on that would enable researchers to seek unidentified cancer-causing mutations, which could be helpful for drug development. The test may help identify which patients should receive which drugs.