ThinPrep Pap Test Platform Seen as 21st Century Pap; New Study Demonstrates Wide Range of Molecular Applications.

Business Editors and Health/Medical Writers

BOXBOROUGH, Mass.--(BW HealthWire)--Aug. 14, 2000

Cytyc Corporation (Nasdaq:CYTC) today announced that a major new study published in the prestigious American Journal of Obstetrics and Gynecology highlights the wide range of potential diagnostic applications provided by the ThinPrep(R) Pap Test(TM). The study titled, "Molecular Papanicolaou tests in the twenty-first century: Molecular analyses with fluid-based Papanicolaou technology," utilized the ThinPrep Pap Test and the Company's proprietary PreservCyt(R) Solution to conduct multiple molecular analyses at the DNA, RNA, and protein level.

The investigators at the University of Texas Southwestern Medical Center demonstrated the feasibility of analyzing genomic DNA for the identification of human papillomavirus E6 and the tumor suppressor gene p53, both of which have been recently implicated in the development of cervical cancer. In addition, the status of the p16 tumor suppressor gene and the gene for E-cadherin, also identified in the oncogenic process, were successfully identified. Total RNA extracted from residual cellular material in the ThinPrep Pap Test vials was preserved and viable for further analysis of the p53 gene. The authors note that cancer-causing molecular errors also occur at the RNA level. ThinPrep slides were also successfully used for immunohistochemical staining for carcinoembryonic antigen, which is selectively expressed in adenocarcinoma. The study employed a variety of analytic tools primarily based on the state-of-the-art polymerase chain reaction (PCR) methodology.

The authors conclude, "We have demonstrated the ThinPrep methanol fixation fluid-based collection of cervical cytologic specimens preserves cellular contents that are useful for detailed molecular analysis." The authors observe that the "relatively simple and widely used" ThinPrep System will allow significant advances in molecular epidemiology and "may facilitate the development of biomarkers capable of assessing individual risk of progression to cervix cancer."

"This is the most comprehensive study to date, demonstrating the significant potential of the ThinPrep Pap Test. It is also interesting to note that this study was published in the same prestigious journal that published the original study by Dr. Papanicolaou in 1941," said Patrick J. Sullivan, Cytyc's president and chief executive officer. "We believe that in the 21st Century, the ThinPrep Pap Test will continue to advance the important contribution to women's health made by Dr. Papanicolaou in the 20th Century."

Cytyc Corporation develops, manufactures, and markets the ThinPrep(R) System for medical diagnostic applications. The ThinPrep System consists of the ThinPrep(R) 2000 Processor, ThinPrep(R) 3000 Processor, and related reagents, filters, and other supplies.

Cytyc(R), ThinPrep(R), and PreservCyt(R) are registered trademarks and ThinPrep(R) Pap Test(TM) is a trademark of Cytyc Corporation.

Forward-looking statements in this press release are made pursuant to the provisions of Section 21E of the Securities Exchange Act of 1934. Investors are cautioned that statements in this press release which are not strictly historical statements, including, without limitation, statements regarding management's plans and objectives for future operations, product plans and performance, potential savings to the healthcare system, management's assessment of market factors, as well as statements regarding the strategy and plans of the Company, constitute forward-looking statements which involve risks and uncertainties, which could cause actual results to differ, including, without limitation, risks associated with the Company's dependence on a single product, uncertainty of market acceptance and additional cost, dependence on proprietary technology, dependence on timely and adequate levels of third-party reimbursement, dependence on key personnel, management of growth, limited marketing and sales experience, and limited number of customers and lengthy sales cycle, as well as risks of downturns in economic conditions generally, and in the healthcare industry specifically, risks associated with competition and competitive pricing pressures, potential liabilities and costs associated with litigation, and other risks detailed in the Company's filings with the Securities and Exchange Commission, included in its 1999 Form 10-K filed with the Commission.