For Immediate Release

MARLBOROUGH, Mass., (Apr 3, 2006) - Cytyc Corporation, a leading women's health company, today announced that four studies describing a variety of clinical and cost benefits of the ThinPrep(R) Pap Test were published in the April 2006 issue of Cytopathology, the official journal of the British Society of Clinical Cytology. The studies were conducted in Canada, Scotland, Ireland, and England.

A study by Duggan et al., of the University of Calgary in Canada, compared ThinPrep Pap Test and conventional cytology results in a Canadian cohort. The study included more than 2,000 patients in each group. The authors report a statistically significant increase in the detection of high-grade squamous intraepithelial lesions (HSIL) in patients screened with the ThinPrep Pap Test compared to those screened with the conventional smear. The study also reported that follow-up results of HSIL and more severe lesions showed the ThinPrep Pap Test group had a higher number of tests confirmed as HSIL or malignant and exceeded the number of confirmed conventional tests by 60 percent.

A study conducted by Dr. A. R. W. Williams at the Royal Infirmary of Edinburgh in Scotland compared cytology results for a 12-month period when the ThinPrep Pap Test was used exclusively versus a 12-month period when conventional smears were used. Results of the analysis showed the reporting rates for all grades of cytologic abnormality increased in the ThinPrep Pap Test period, while the positive predictive value (PPV) also improved in this group. In addition, the rate of unsatisfactory specimens fell from 13.6 percent with conventional smears to 1.9 percent with the ThinPrep Pap Test.

"The Scottish Cervical Screening Programme was the first national program to commit to complete conversion to the ThinPrep Pap Test," said Dr. Williams. "I believe our data as well as the cumulative findings of the other studies published in the current issue of Cytopathology, clearly validate that decision. We have been very pleased with the performance of the ThinPrep Pap Test in our laboratory, and there have been important downstream benefits to colposcopy clinics and to the women being screened."

Doyle et al., at St. Luke's Hospital in Dublin, assessed the effects on productivity with implementation of the ThinPrep Pap Test over a two-year period. Based on output of cases per medical scientist, there was a 31 percent increase in output at 73 percent conversion to the ThinPrep Pap Test. The authors also reported "a definite decreasing trend" in the overall number of unsatisfactory cases as the percentage conversion to the ThinPrep Pap Test increased.

In a study conducted at Manchester Royal Infirmary and Stepping Hill Hospital, Stockport, England, Dowie et al., evaluated the impact on cervical smear reader efficiency with implementation of the ThinPrep Pap Test. The investigators conducted a series of timing surveys, in which the slide readers used timers to record time taken to examine and report each slide. The author reported that the timing surveys confirm that the ThinPrep Pap Test can improve laboratory efficiency.

"The results from international institutions continue to build on the substantial body of evidence that shows improvement in productivity and clinical effectiveness wherever the ThinPrep Pap Test is implemented in the world," said David Harding, president Cytyc International. "It is also noteworthy that all four studies evaluating liquid-based cytology, published in this prestigious journal, utilized the ThinPrep Pap Test exclusively."