Wikimedia, Calle Eklund/V-wolfBy sifting through DNA sequences floating in the bloodstream, researchers may be able to detect, early on, the genetic hallmarks of cancer. The developing diagnostic method follows a new finding, published this week (November 28) in Science Translational Medicine, that colorectal and breast cancer patients carry altered chromosomes in their blood—released from tumors—while healthy patients do not.
"The approach has tremendous promise and, should the sequencing strategy become economical, it could have important applications in early cancer detection," Daniel Haber of Massachusetts General Hospital in Boston, who was not involved in the study, told ScienceNOW.
However, the method isn’t yet sensitive enough to detect early cancers, mainly because the cost of sequencing is prohibitively expensive. The blood tests that detected late stage cancers cost thousands of dollars per patient. But researchers are hopeful that as the price of sequencing falls, not only will the test become more affordable, researchers will be able to increase the sequencing coverage to detect the tiny amount of tumor DNA found in the bloodstream early in cancer development will become feasible. “In the very near future, this could end up being extremely cheap,” senior author Victor Velculescu, of the Johns Hopkins University School of Medicine in Baltimore, told ScienceNOW. Other researchers speculated that such tests could be available in 5 to 10 years.