We have all been affected by cancer one way or another, whether through a friend, relative, or personal experience. Therefore, when it comes to saving lives from the potentially fatal disease, the earlier the diagnosis, the better. Now, British researchers suggest a cancer diagnosis may be as simple as a pinprick, a blood test, which can help measure damage to white blood cells using ultraviolet light (UVA) wavelength, according to a recent study published in The Federation of American Societies for Experimental Biology Journal.
The blood test, formally known as at the Lymphocyte Genome Sensitivity (LGS) test, looks at white blood cells and measures the damage caused to their DNA when subjected to different intensities of UVA, which is known to damage DNA. The immune system houses many types of white blood cells, each fighting infection in a special way. A low white blood cell count, specifically a low level of neutrophils (neutropenia) — the most important infection-fighting white blood cells — says the Mayo Clinic, poses a higher risk for the body to develop an infection. A healthy person has an absolute neutrophil count between 2,500 and 6,000.
Since white blood cells help the body ward off infections, the British researchers sought to unveil what they can discover if they put them under further stress. Typically, white blood cells are under stress when they are fighting cancer or other diseases. “[S]o I wondered whether anything measureable could be seen if we put them under further stress with UVA light,” said Professor Diana Anderson, lead author of the study from the University of Bradford’s School of Life Sciences, according to the news release.
To explore this concept, Anderson and her colleagues subjected white blood cells under further stress using UVA light. The study analyzed blood samples taken from 208 individuals. A total of 94 individuals were recruited from staff and students at the University of Bradford, and 114 blood samples were collected from patients referred to specialist clinics within Bradford Royal Infirmary prior to diagnosis and treatment. The samples were coded, anonymized, randomized, and then exposed to UVA light through five different depths of agar.
UVA damage was observed in the form of pieces of DNA being pulled in an electric field toward the positive end of the field, causing a comet-like tail. In the LGS test, the researchers found the longer the tail, the more DNA damage. There was also a significant distinction between damage to the cancerous cells, and the cells from healthy patients.
"We found that people with cancer have DNA which is more easily damaged by ultraviolet light than other people, so the test shows the sensitivity to damage of all the DNA — the genome — in a cell," Anderson said. The measurements correlated to those patients who were ultimately diagnosed with cancer (58), those with pre-cancerous conditions (56), and those who were healthy (94). The test has accurately diagnosed lung, skin, and colon cancer, which are quite difficult to detect, according to Medical News Today.
Anderson and her colleagues are aware these “early results completed on three different types of cancer,” and they accept that more research needs to be done, but “these results so far are remarkable,” she said. Although the sample size was small, the researchers suggest the findings are “powerful,” and could confirm the test’s potential as a diagnostic tool.
Cancer researchers like Shirley Hodgson, a professor of cancer genetics at St. George's, University of London, remain skeptical about the accuracy of the blood test. "Overall, this is a small study with very significant limitations," she told the BBC. "A much bigger experiment, including better-controlled groups of patients, is needed before we can determine how useful the test could be in cancer diagnosis.”
Currently, there is a clinical trial underway at Bradford Royal infirmary to investigate the test’s accuracy with patients suspected to have colorectal cancer. While it seems like the researchers have their work cut out for them, a “universal” blood test for cancer may not be overreaching. Prevention and early detection may help save the lives of eight million people who die from cancer worldwide, according to the Centers for Disease Control and Prevention.
Source: Anderson D, Britland ST, Davies J, et al. Sensitivity and specificity of the empirical lymphocyte genome sensitivity (LGS) assay: implications for improving cancer diagnostics The Federation of American Societies for Experimental Biology Journal. 2014.