New Blood Test for Early Detection of Cancer

The "lymphocyte genome sensitivity" (LGS) test can predict if a person has or is at risk for cancer, say researchers. Professor Diana Anderson, of the University of Bradford (UK), and colleagues took blood samples from a group of people that included healthy individuals, cancer patients and people believed to be at increased risk of developing cancer. White blood cells (lymphocytes) in these samples were examined in a Comet test, by embedding the cells in agar on a microscope slide. The DNA of the cells was then damaged by treatment with ultraviolet (UVA) light. The damage was observable in the form of DNA pieces being pulled within the agar in an electric field toward the positive end of the field, creating a comet-like tail (the longer the tail the more DNA damage). Different thicknesses of agar were then applied to the slides. In healthy people, as different thicknesses were added, DNA-damaged tail responses returned to normal levels. Whereas in cancer patients, the DNA-damaged tail responses remained high, and in those people who might develop pre-cancerous diseases, tail responses were in between. These results imply that people with cancer have DNA that is more easily damaged by UVA than cancer-free people. The LGS test was used to examine blood samples from cancer patients with melanoma, colon cancer and lung cancer, and all gave the same result. "The test could allow earlier cancer detection, so helping to save peoples' lives," said Professor Anderson.