Cytyc Announces Posting of UK Department of Health Report Evaluating Liquid-Based Cytology.

Business Editors/Health/Medical Writers

BOXBOROUGH, Mass.--(BUSINESS WIRE)--March 18, 2003

Cytyc Corporation (Nasdaq:CYTC) announced today that the first report to the United Kingdom (UK) Department of Health evaluating liquid-based cytology (LBC) has been posted on the National

Cancer Screening Programme website page. The report presents results from the pilot study conducted at three sites in England that converted fully to using liquid-based cytology using two different technologies. The ThinPrep(R) Pap Test was used at two of the sites, sites A and C, and one site, site B, used SurePath(TM). The report evaluated a number of factors including disease detection, specimen adequacy, productivity, and cost-effectiveness.

Regarding disease detection, the report shows that the ThinPrep Pap Test significantly increased the detection of moderate and severe dyskaryosis compared to the conventional Pap smear. The report states, "Overall, across all sites, there was no significant increase in the rates of moderate and severe dyskaryosis separately or combined for the six month pilot period when expressed as a percentage of all adequate smears." However, when individual site data was analyzed, the study found, "There was a non-significant 11% decrease in the rate of moderate and severe dyskaryosis in site B compared to the pre-pilot period, and a significant 17% increase in sites A and C combined (RR 1.17%, 95% CI 1.055, 1.300) compared to the pre-pilot period. This is largely due to differences in the rates of severe dyskaryosis, for which the increase in sites A and C combined (RR 1.381, 95% CI 1.187, 1.605) and the decrease in site B (RR 0.655, 95% CI 0.523, 0.814) are both significant."

The study also reports, "For all sites combined there is an 82.7% reduction in the rate of inadequate smears in the 6 month pilot period (9.1% pre-pilot vs. 1.6% pilot, p is less than 0.0001)." For the ThinPrep-only sites the reduction was 77.8% (9.0% pre-pilot vs. 2.0% pilot).

The report also notes productivity increased with LBC and that the introduction of LBC "resulted in a reduction in the backlog of smears at laboratories, and hence in reporting times of smears." The cost-effectiveness analysis found that "LBC is cost saving across both technologies."

"While we are extremely pleased, we are not surprised by the report's findings," said Patrick J. Sullivan, Cytyc's chairman, president, and chief executive officer. "We have come to expect the improved clinical performance of the ThinPrep Pap Test, which is consistently reproduced in clinical studies and published literature. The scientific evidence of the clinical benefits of the ThinPrep Pap Test is comprehensive, compelling, and unique."

The full report can be found at: www.cancerscreening.nhs.uk/cervical/research.html#evaluation-lbc.

Cytyc Corporation develops, manufactures, and markets products for medical diagnostic applications primarily focused on women's health. The ThinPrep(R) System consists of the ThinPrep(R) 2000 Processor, ThinPrep(R) 3000 Processor, 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.

Investors are cautioned that statements which are not strictly historical statements, including statements regarding management's plans and expectations with respect to future business strategy, product development, operations and results, constitute forward-looking statements which involve risks and uncertainties which could cause actual results to differ. Such risks include the Company's dependence on a limited number of products, uncertainty of market acceptance and additional cost, dependence on proprietary technology, competition and competitive pricing pressures, uncertainties regarding regulatory approvals and developments, and other risks detailed in the company's filings with the Securities and Exchange Commission. Statements contained in this press release are made as of the date hereof and Cytyc assumes no obligation to update such information based on events that may occur after that date.