TPTH Tripath Imaging

Study indicates that density gradient separation process employed by SurePath(R) Liquid Based Pap test handled significantly greater amounts of potentially obscuring blood than competing membrane filtration method BURLINGTON, N.C., May 4 /PRNewswire-FirstCall/ -- TriPath Imaging, Inc. (NASDAQ:TPTH) today announced that investigators from the Caritas St. Elizabeth's Medical Center and Tufts New England Medical Center in Boston, Massachusetts have reported the results of a study in which the gradient density separation or Cell Enrichment(TM) process employed by the SurePath liquid based cytology system capably handled significantly greater amounts of potentially obscuring blood than the competing membrane filtration method. The results of this study are presented in an article entitled "Comparison of the effectiveness of two liquid-based Papanicolau systems in the handling of adverse limiting factors, such as excessive blood" that appears in a recent edition of Cancer CytoPathology (Cancer Cytopathology February 25, 2006; vol 108:27-31). In the study, reported by Brenda J. Sweeney et al, conditions of excessive blood were simulated and a prepared suspension combining the cellular residue from fifteen SurePath collection vials was used. The study results were that the SurePath methodology preparations were uncompromised until reaching aliquots of 1000 microliters to 3000 microliters of blood; whereas, the competing membrane filtration-based methodology was severely compromised by the addition of as little as one drop (50 microliters) to 100 microliters of the blood preparation. The SurePath liquid based Pap test employs density gradient separation and centrifugation, a Cell Enrichment process that facilitates the separation of epithelial cells of interest from blood and other obscuring materials. With the competing membrane filtration method, the cells of interest are separated when the liquid collection medium is drawn through a filter using negative pressure pulse. "The ability to minimize the impact of blood and other potentially obscuring materials is a key feature of our slide preparation process and clearly differentiates the SurePath liquid based Pap test," said Ray Swanson, TriPath Imaging's Senior Vice President of Commercial Operations. "This effectiveness of our Cell Enrichment process, particularly as it relates to the handling of adverse limiting factors such as excessive blood, is well appreciated by both our clinician and laboratory customers." In the study reported by Sweeny et al, conditions of excessive blood were simulated by adding sequentially increasing volumes of a red blood cell/buffy coat mixture to liquid based cervical specimens. Test preparations were developed by combining resuspended cellular residue from SurePath gynecologic specimens with increasing volumes of the red blood cell mixture and dispensing them into nine or ten vials appropriate to each of the two methods. Cytology specimens were processed using the SurePath density gradient system or the competing membrane filtration method one day after blood was added. The cellularity of the resulting slides and determination of slide adequacy for cytologic assessment was then assessed by microscopic examination. The authors noted that if processing by membrane filtration occurred immediately after the addition of blood, the negative impact of the addition of blood on slide adequacy was slightly reduced. However, reduction in adequacy dramatically increased over several hours. In comparison, with SurePath processed slides storage time was not a factor in affecting adequacy. Sweeney et al concluded the sharply contrasted results demonstrate systemically a technical limitation of the competing membrane filtration system in coping with excessive blood while using the procedures in the approved labeling. Further investigation of technological differences in liquid-based Pap smear methodologies may yield additional data regarding specimen adequacy. TriPath Imaging, Inc., headquartered in Burlington, North Carolina, develops, manufactures, markets and sells innovative solutions to improve the clinical management of cancer, including detection, diagnosis, staging and treatment. TriPath Oncology, a wholly owned subsidiary of TriPath Imaging, develops molecular diagnostic products for malignant melanoma and cancers of the cervix, breast, ovary and prostate. For more information on TriPath Imaging please visit our web site at http://www.tripathimaging.com/. Investors are cautioned that statements in this press release that are not strictly historical statements constitute forward-looking statements which involve risks and uncertainties that could cause actual results and outcomes to differ materially from what is expressed in those forward-looking statements. Such forward-looking statements include, without limitation, those related to the market acceptance of TriPath Imaging's products, and product development efforts. Important factors that may affect such forward-looking statements include, without limitation: TriPath Oncology may be unable to successfully develop and commercialize products and services when anticipated, if at all; TriPath Imaging's products may not achieve or maintain market acceptance to the degree anticipated; TriPath Imaging and TriPath Oncology's products may not receive FDA or other required regulatory approval when expected, if at all; and other risks detailed in TriPath Imaging's filings with the Securities and Exchange Commission, including those described in TriPath Imaging's Annual Report on Form 10-K for the year ended December 31, 2005. Contact Stephen P. Hall Chief Financial Officer 336-290-8721 DATASOURCE: TriPath Imaging, Inc. CONTACT: Stephen P. Hall, Chief Financial Officer of TriPath Imaging, Inc., +1-336-290-8721 Web site: http://www.tripathimaging.com/

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