Chronix Biomedical’s DNA Blood Tests Detect Breast and Prostate Cancer with 92% Sensitivity and 100% Specificity
News Jun 07, 2010
Chronix Biomedical today reported new data further demonstrating that its DNA blood tests have the potential to accurately detect early stage breast and prostate cancers. Chronix’s proprietary technology identifies disease-specific genetic fingerprints based on DNA fragments that are released into the bloodstream by damaged and dying (apoptotic) cells.
In this new study of 575 individuals, Chronix’s assays detected and identified DNA fingerprints in the blood that indicated the presence of prostate or breast cancer with 92% sensitivity and 100% specificity, significantly outperforming the published accuracy data for current diagnostic methods. The new study results will be presented in an oral session today at the 2010 ASCO Annual Meeting in Chicago.
Breast cancer expert, Steven Narod, M.D., F.R.C.P.C., noted: “These new data, although early, provide further evidence that Chronix’s proprietary DNA blood test may represent a new diagnostic and prognostic platform that can identify cancer earlier and more accurately than is currently possible. I am pleased to be working with Chronix to further validate these promising findings.” Dr. Narod is Director of the Familial Breast Cancer Research Unit at Women’s College Research Institute, an affiliate of the University of Toronto.
The tests use proprietary algorithms developed by Chronix researchers to detect, analyze and identify cancer-related fragments of DNA that are released into the bloodstream by apoptotic cells. Chronix researchers consistently find that this apoptotic DNA in the blood originates from a limited number of regions, or “hotspots,” on the genome that are specific to each cancer.
According to the data to be presented today, the presence of DNA fragments from any one of the 29 unique “hotspots” associated with breast cancer indicates that breast cancer is present in the patient. The presence of DNA fragments from any one of the 32 unique “hotspots” associated with prostate cancer, which are different from the breast cancer “hotspots,” is indicative of the presence of prostate cancer.
“By focusing on these blood-borne genomic ‘hotspots,’ we can reliably detect the presence of cancer without having first to isolate and analyze the tumor cells,” said Howard Urnovitz, Ph.D., Chief Executive Officer of Chronix and a co-author of the study. “If verified by further studies, our Chronix blood-based assays would make it possible to diagnose cancer at its earliest stages, track progress as patients undergo treatment and personalize treatment using patients’ disease-specific genomic fingerprints.”
The testing involved 575 individuals: 178 with early stage breast cancer, 197 with invasive prostate cancer and 200 healthy controls. The Chronix assay detected breast cancer with 92% sensitivity and 100% specificity. Although not directly comparable, for reference it is noteworthy that data from a large study of U.S. mammography screening programs reported an overall specificity of 92.3% and sensitivity of just 75%, with lower figures for some populations such as younger women. The Chronix assay also detected invasive prostate cancer with 92% sensitivity and 100% specificity.
In contrast, the widely used PSA (prostate specific antigen) test has previously demonstrated 85% sensitivity and a specificity of just 25% to 35%. If the Chronix data are confirmed in larger studies, they have the potential to reduce the current rate of false positive and false negative results that contribute to poorer patient outcomes and higher healthcare costs.
Previous published studies have demonstrated that the Chronix approach can identify the presence or absence of active disease in multiple sclerosis patients and that it can accurately detect early stage breast cancer with high diagnostic sensitivity and specificity. Commercial applications for veterinary use are in development in conjunction with the University of Calgary, including tests for the early detection of BSE, or mad cow disease.
Dr. Urnovitz added, “With these encouraging findings, we are launching a ‘For Investigational Use Only’ testing service that for the first time will enable cancer researchers to monitor the status of patients in their clinical trials with a high level of sensitivity and specificity, potentially accelerating clinical trials and increasing their chances for success.”
Patient data collected from this new service for clinical researchers along with additional planned clinical studies are expected to expand the database needed to obtain regulatory approval for the use of Chronix assays in ongoing cancer patient care.
Oral presentation: “Comparative analysis of the chromosomal origins of circulating nucleic acids in breast and prostate cancer”.