A new report shows early detection of cancer could one day be as easy as a simple blood test. This test, called the "lymphocyte genome sensitivity" (LGS) test, could not only detect some cancers earlier than ever before, but it may eliminate the need for some types of biopsies, as well as identify those more likely to develop cancer in the future.

 "The test could allow earlier cancer detection, so helping to save peoples' lives," said Diana Anderson, co-author at the University of Bradford in West Yorkshire, United Kingdom.  

To develop this test, Anderson and colleagues took blood samples from a group of people that included healthy individuals, cancer patients and people believed to be at a higher risk than normal to develop cancer.

White blood cells (lymphocytes) in these samples were examined in a Comet test, by embedding the cells in a jelly-like substance, called agar, on a microscope slide. In this test, damage to the genetic material (DNA) of the cells was caused by treatment with ultraviolet (UVA) light. This damage was observed in the form of DNA pieces being pulled within the agar in an electric field toward the positive end of the field. This caused a comet-like tail, and the longer the tail the more DNA damage.

Different thicknesses of the agar were applied to the slides. In healthy people, as different thicknesses were added, DNA-damaged tail responses returned to normal levels. In cancer patients, DNA-damaged tail responses remained high and in those people who might develop pre-cancerous diseases, tail responses were in between. This means that people with cancer have DNA which is more easily damaged by UVA than do other people, so the test shows the sensitivity to damage of all the genome in a cell.

The LGS test has been used to examine blood samples from cancer patients with melanoma, colon cancer and lung cancer, and all gave the same outcomes.