New Quantitative Survey Confirms Improved Performance of ThinPrep Pap Test.

Business Editors/Health/Medical Writers

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BOXBOROUGH, Mass.--(BUSINESS WIRE)--July 2, 2003

An independent, quantitative survey published this week reports on the improved sensitivity and specificity of the ThinPrep(R) Pap Test compared to the conventional Pap smear for the detection of cervical dysplasia reported Cytyc Corporation (Nasdaq: CYTC). The study analyzed 24 published studies to assess the consistency of the two methods and to assess the accuracy of each method.

The study by Ovadia Abulafia, M.D., and others, appears in the July 2003 issue of Gynecologic Oncology. The authors conducted searches of computerized databases for literature published between January 1990 and September 2002. The searches yielded 47 potentially relevant articles. The authors then identified 24 articles that met the criteria established for their evaluation.

Based on their findings the authors conclude, "According to our analysis, wide application of the ThinPrep technology potentially may result in cytological diagnosis of an additional 162,000 patients with HGSIL and 3000 patients with invasive cervical carcinoma whom otherwise would have been missed by utilization of conventionally prepared Papanicolau smears (false-negative smears). We conclude that ThinPrep liquid-based cervical cytology should be considered the standard of care, as this technology has the potential to further reduce the incidence and increase the survival of patients with invasive cervical carcinoma as a result of early detection."

"This important independent study is a significant addition to the formidable body of evidence demonstrating the improved clinical performance of the ThinPrep Pap Test," said Patrick J. Sullivan, Cytyc's chairman, president, and chief executive officer. "I believe the consistency of the reported benefits in the published literature serves to validate our claims of the improved diagnostic performance of the ThinPrep Pap Test and provides a clear differentiation from other technologies."

"This is the second independent analysis of previously published studies evaluating the ThinPrep Pap Test," added James Linder, M.D., Cytyc's chief medical officer. "In 2001, Bernstein et al. published a meta-analysis of 25 studies in the American Journal of Obstetrics and Gynecology demonstrating that the ThinPrep Pap Test improves diagnosis of high-grade squamous intraepithelial lesions (HSIL) compared to the conventional Pap smear. The current quantitative analysis by Abulafia et al. applies different methodology and inclusion criteria, focusing primarily on split-sample studies, yet the findings continue to confirm improved diagnostic performance."

Cytyc Corporation designs, develops, manufactures, and markets the ThinPrep(R) System for use in medical diagnostic applications primarily focused on women's health. The ThinPrep System is widely used for cervical cancer screening and is the platform from which the Company has launched its expansion into breast cancer risk assessment with the FirstCyte(TM) Breast Test. The ThinPrep System consists of the ThinPrep(R) 2000 Processor, ThinPrep(R) 3000 Processor, ThinPrep(R) Imaging System, and related reagents, filters, and other supplies. Cytyc is traded on The Nasdaq Stock Market under the symbol CYTC.

Cytyc and ThinPrep are registered trademarks of Cytyc Corporation. FirstCyte is a trademark of Cytyc Corporation for which registration has been applied.

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 relating to the Company's financial condition, operating results and future economic performance, and management's expectations regarding future growth opportunities, product acceptance and business strategy, constitute forward-looking statements. These statements are based on current expectations, forecasts and assumptions that are subject to risks and uncertainties, which could cause actual outcomes and results to differ materially from those statements. Risks and uncertainties include, among others, dependence on key personnel and proprietary technology, uncertainty of product development efforts, product acceptance, management of growth, risks associated with litigation, competition and competitive pricing pressures, risks associated with the FDA regulatory approval processes and any healthcare reimbursement policies, and other risks detailed in the Company's filings with the Securities and Exchange Commission, including under the heading "Certain Factors Which May Affect Future Results" in its 2002 Annual Report on Form 10-K and its most recent Quarterly Report on Form 10-Q filed with the Commission. The Company cautions readers not to place undue reliance on any such forward-looking statements, which speak only as of the date they were made. The Company disclaims any obligation to publicly update or revise any such statements to reflect any change in Company expectations or events, conditions, or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.