| ISMagazine.com | Medicine, Health, and Fitness |
October, 1999 |
Automated Cellular Imaging System (ACISTM) from ChromaVision 300 Percent More Sensitive than Existing Testing Models
SAN
JUAN CAPISTRANO, CA, (July 29, 1999).... The U.S. Food and Drug Administration (FDA)
cleared for marketing a powerful new tool that may help physicians detect cancer,
infectious diseases and genetic conditions earlier and more accurately, potentially
leading to improved patient treatment. The ACIS system from ChromaVision, which can be
applied to a vast number of existing laboratory diagnostic tests, is designed to greatly
enhance a physician's ability to detect disease at the cellular level utilizing color. The
ACIS combines proprietary, color-based imaging technology with automated microscopy to
increase detection sensitivity more than 300 percent over existing manual testing methods.
The FDA clearance obtained is for use of the ChromaVision Automated Cellular Imaging System, or ACISTM, with a widely used staining method called immunohistochemistry, or IHC. Immunohistochemistry is commonly used in the evaluation of numerous disease conditions. This single clearance enables the commercialization of five ACIS tests scheduled for release in 1999 and paves the way for rapid introduction of future ACIS tests.
"While Pathologists are accurate in many situations in detecting cancerous or diseased cells, the human eye is subject to significant limitations. Specifically with the detection of rare tumor cells or micrometastases, pathologists may underestimate or miss entirely cancer cells that can be detected by a system like the ACIS," says Dr. Michael F. Press, M.D., Ph.D., Professor, Department of Pathology, University of Southern California, Kenneth Norris Jr. Comprehensive Cancer Center. "The ability of the ACIS system to detect suspected tumor cells in remote areas of the body at a relatively early stage allows specific patient treatment, resulting in a lower chance of disease reoccurrence and ultimately, a better chance of survival."
Used in conjunction with the immunohistochemical (IHC) class of stains, the ACIS system is able to "red flag" abnormal cells, by detecting acute color differences. This enhanced sensitivity enables the system to detect one abnormal cell among 100 million normal cells in a specific application that identifies suspected tumor cells. In a clinical study designed to diagnose the presence of cancer micrometastases in bone marrow, 44 percent of the slides initially called negative by traditional manual review were correctly identified as positive by a pathologist using the ACIS. The review of the slides with the ACIS system resulted in a 300% increase in sensitivity to detect tumor cells over traditional manual methods. Results from related studies performed in the trial demonstrated 100% accuracy for pathologists using the ACIS to identify tumor cells in bone marrow samples.
More than one billion slide-based diagnostic procedures are performed in the U.S. each year. Currently, pathologists manually compare samples of human cells or tissue for characteristic patterns or color variations that suggest the presence of disease. While the human eye is superb at pattern recognition, it is limited in distinguishing subtle variations in color. As a result, some lab tests are highly subjective and results may vary depending upon who interprets the test, potentially leading to inaccurate positive or negative conclusions.
Using color as the primary means of analyzing samples, the ACIS helps the pathologist achieve an unprecedented level of accuracy and objectivity in the detection of disease at the cellular level. For example, when reading a test to measure the overexpression of the HER2 protein in breast cancer patients, the pathologist is challenged to quantify the level of brown stain present in a tissue sample from the patient. The ACIS system has the ability to discriminate and reliably score 255 levels of color intensity versus only 4 color levels detectable by the human eye. Quantification of the HER2 protein is used to determine which patients would most benefit by treatment with a newly approved therapeutic drug, Herceptin®, developed by Genentech. Current manual visual assessment of the overexpression of the HER2 protein is semi-quantitative and subject to interpretation.