Last week CDx Diagnostics announced the release of a new brush biopsy system that promises to improve the sensitivity of pre-cancerous esophageal adenocarcinoma testing. As founder and CEO of the company, Mark Rutenberg has been developing the technology behind the EndoCDx brush biopsy. He kindly agreed to answer a few of our questions about this technology and what it offers clinicians and their patients.
Medgadget: Mr. Rutenberg, what is the advantage of using your brush biopsy system as opposed to standard cytology brushes?
Mark Rutenberg: The EndoCDx biopsy brush collects a complete biopsy sample of the entire thickness of the epithelium, or mucous membrane, whereas cytology only captures surface cells that have been exfoliated. In addition, the EndoCDx sample is a three-dimensional tissue sample, containing intact and uncut tissue fragments, allowing for a more complete picture of the lining of the esophagus. EndoCDx uses advanced computer technology that has become available only recently to analyze these disaggregated samples.
Medgadget: Your materials mention that the “tissue sample is subjected to a powerful three-dimensional computer assisted laboratory search for any precancerous cells.” Your website also mentions an algorithm developed as part of the “Star Wars” missile defense program. This is fascinating stuff – could you comment on what this means, as compared to a pathologist looking at a traditional tissue slices?
Mark Rutengerg: EndoCDx brush biopsy does incorporate advanced computer technology to analyze the unique three-dimensional tissue sample and identify cells with Barrett’s esophagus or dysplasia. Our computers perform a large number of mathematical calculations on each cell, as many as 4 billion operations per second, to identify abnormalities, such as an enlarged cell nucleus or other unhealthy markers. The neural network performs additional, sophisticated tests on every cell on the slide, allowing any sign of potential abnormality to be caught at the earliest possible stage.
In a typical pathology review, the pathologist is analyzing an artificially thin sample that may be only one micron thick and does not resemble the cell as it appears in vivo, or in the human body. The CDx technology incorporates an extended depth of field, known as EDF, which images the entire sample from all focal planes, providing our pathologists with a complete three-dimensional depth of field that is much closer to the way the cells and tissue appear in the body. The CDx computer technology is able to identify as few two goblet or dysplastic cells on a slide containing more than 100,000 cells, in multiple focal points. The computer system identifies the top 200 cells of interest, which are then reviewed by our cytopathologist.
This is very different from the standard tissue slice review, which is dependent upon human subjectivity. Additionally in a standard esophageal biopsy, to obtain the very thin tissue slices that are viewed under the microscope a portion of cells that are removed from the sample and never reviewed. In brush biopsy, we analyze every cell that is sent to our lab.
Medgadget: How does this process compare to the usual method in terms of the time it takes to do the procedure and the cost (equipment + cost of processing and interpreting samples)? We are referring specifically here to esophageal cancer screening.
Mark Rutengerg: Incorporating EndoCDx brush biopsy into an endoscopy procedure adds just a few minutes to the procedure, the time it takes to insert the brush into the working channel of the endoscope, to collect the sample and to prepare the sample for sending to the lab. The procedure is coded as an additional biopsy sample, and reimbursement is made by payers directly to the lab, so there is no cost to the facility, the physician or to the patient. There is no charge to the institutions or facilities for the CDx test kit.
Traditional four-quadrant forceps biopsy is coded in the same way but samples a much smaller portion of the esophagus compared to EndoCDx brush biopsy, which leaves open the possibility that areas of Barrett’s esophagus or dysplasia may not be included in the tissue sample being reviewed by the pathologist. It is widely accepted among gastroenterologists that standard esophageal biopsy misses abnormalities. There are several clinical studies regarding the limitations of four-quadrant forceps biopsy, and we feel that EndoCDx, in conjunction with forceps biopsy, provides a more comprehensive solution to detecting Barrett’s esophagus and dysplasia. Two clinical studies were recently published in Digestive Diseases and Sciences, that showed EndoCDx detected 40% more Barrett’s esophagus in GERD patients and a more than 40% increase in the detection of dysplastic cells in high risk patients compared to traditional forceps biopsy.
Medgadget: We have been focusing on the use of your technology in detecting esophageal cancer. We also notice that you also offer oral and laryngeal cancer screening tools. Does the analysis of these brushings use a similar “neural network” approach?
Mark Rutengerg: These oral and laryngeal specimens also benefit from the CDx approach of wide area tissue sampling and three-dimensional computer assisted analysis. Our computers are programmed to assess cells differently based upon the type of cancer being detected, and our human pathologists are trained in identifying high-risk cells in each area we test.
Medgadget: Final question. What does the future hold for CDx Diagnostics? Are there any other exciting products in the pipeline that we should be looking for?
Mark Rutengerg: Currently our focus is in launching this technology in the esophagus; however, there is broad interest in applying this technology to other areas of the gastrointestinal tract.