Every type of cancer is unique depending on which cells are affected, how it spreads, and what causes it to arise in the first place. That has been the basic understanding that has marked cancer as an overarching concept for a variety of uniquely different diseases and so each cancer required its own diagnostic mechanism and treatment regimen. Researchers at University of Bradford have now come up with a new test that may be able to spot the presence of just about any cancer in a sample of a patient’s blood. Unlike many other tests that spot anatomical changes, identify specific biomarkers, or filter out circulating tumor cells, the new technique relies on damaging DNA taken from blood samples.
The researchers took blood draws from patients with lung, colon, and melanoma cancers, as well as from healthy volunteers. They then used ultraviolet light to attempt to damage DNA molecules within white blood cells from the samples taken and then analyzed the results. They discovered that DNA seems to be more easily damaged when a person is already a cancer host, and people with pre-cancerous conditions have more fragile DNA than healthy subjects.
Some details from the study abstract in The Journal of the Federation of American Societies for Experimental Biology:
Lymphocyte responses from 208 individuals: 20 with melanoma, 34 with colon cancer, and 4 with lung cancer (58), 18 with suspected melanoma, 28 with polyposis, and 10 with COPD (56), and 94 healthy volunteers were examined. The natural logarithm of the Olive tail moment (OTM) was plotted for exposure to UVA through 5 different agar depths (100 cell measurements/depth) and analyzed using a repeated measures regression model. Responses of patients with cancer plateaued after treatment with different UVA intensities, but returned toward control values for healthy volunteers. For precancerous conditions and suspected cancers, intermediate responses occurred. ROC analysis of mean log OTMs, for cancers plus precancerous/suspect conditions vs. controls, cancer vs. precancerous/suspect conditions plus controls, and cancer vs. controls, gave areas under the curve of 0.87, 0.89, and 0.93, respectively (P<0.001). Optimization allowed test sensitivity or specificity to approach 100% with acceptable complementary measures. This modified comet assay could represent a stand-alone test or an adjunct to other investigative procedures for detecting cancer.
Study in The FASEB Journal: Sensitivity and specificity of the empirical lymphocyte genome sensitivity (LGS) assay: implications for improving cancer diagnostics…