Cytyc Corporation Licenses Promising Cancer Detection Technology from University of Massachusetts Medical School.

BOXBOROUGH, Mass. & WORCESTER, Mass. -- Company will also fund research at UMMS for diagnostic and prognostic technology for cervical and breast cancer.

The University of Massachusetts Medical School (UMMS) and Cytyc Corporation (Nasdaq: CYTC) have signed licensing and sponsored research agreements related to cancer detection technology developed at UMMS that may predict the onset and severity of certain cancers before a tumor actually forms.

The technology, which focuses on centrosomes in cancerous and pre-cancerous cells, was developed by Stephen J. Doxsey, Ph.D., associate professor of molecular medicine, biochemistry & molecular pharmacology, and cell biology at UMMS. "The relationship between centrosome abnormalities and cancer is a major focus of our work, so I'm pleased to see this technology taking an important step towards a clinical application," Dr. Doxsey said.

The agreement gives Cytyc a worldwide exclusive license to use Doxsey's technology for developing products in the areas of cancer diagnostics and prognostics. Cytyc will also sponsor research in Doxsey's lab to further explore the science as it applies to breast and cervical cancers. "We are pleased to have the opportunity to work with Dr. Doxsey. His work on centrosomes extends our current research activities in the early detection of cervical and breast cancer," said James Linder, M.D., senior vice president and chief medical officer.

Doxsey is a nationally recognized leader in the study of cell division. His lab is at the forefront of researching the molecular mechanisms that can cause normal cells to mutate into cancerous cells. Much of that work focuses on the centrosome, a small part of a cell that helps chromosomes to line up properly during cell division.

A normal cell has two centrosomes. When the cell divides, the centrosomes pull apart the duplicate sets of chromosomes evenly; thereby making sure each new cell gets its proper complement of DNA. Cancerous cells, however, typically have three or more centrosomes (and/or defective centrosomes) which pull the chromosomes apart haphazardly, so when division occurs the new cells may get either too many or two few chromosomes, causing the genetic instability that leads some cells to grow into aggressive tumors.

In a series of papers in major journals, Doxsey's team has shown that in nearly all carcinomas, including breast, prostate, lung, brain and cervical cancers, the centrosomes are defective either in number, or structure, or both. Doxsey also demonstrated that the centrosome defects are present very early in pre-cancerous lesions, including HPV-induced cervical abnormalities. In addition, the degree of centrosomal defects in certain lesions is correlated to the aggressiveness of the cancer that may eventually develop.

About UMMS

The University of Massachusetts Medical School is one of the fastest growing academic health centers in the country and has built a reputation as a world-class research institution, consistently producing noteworthy advances in clinical and basic research. The Medical School attracts more than $154 million in research funding annually, 80 percent of which comes from federal funding sources. Research funding enables UMMS scientists to explore human disease from the molecular level to large-scale clinical trials. Basic and clinical research leads to new approaches for diagnosis, treatment and prevention of disease.

About Cytyc

Cytyc Corporation is a leading medical device company that designs, develops, manufactures, and markets innovative and clinically effective products primarily focused on women's health. Cytyc products cover a range of women's health applications, including cervical cancer screening, breast cancer risk assessment, and treatment of excessive menstrual bleeding. The ThinPrep(R) System is the most widely used method for cervical cancer screening in the United States. 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. The ThinPrep System also provides the platform from which the Company has launched its expansion into breast cancer risk assessment with the FirstCyte(R) Breast Test. Cytyc Surgical Products, a wholly owned subsidiary of Cytyc Corporation, manufactures and markets the NovaSure(R) Impedance Controlled Endometrial Ablation System, or the NovaSure(R) System, an innovative endometrial ablation device to treat menorrhagia, or excessive menstrual bleeding.

Cytyc is traded on The Nasdaq Stock Market under the symbol CYTC. Cytyc, ThinPrep, FirstCyte, and NovaSure are registered trademarks of Cytyc Corporation.

(For Cytyc Corporation investors)

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, the effective integration of acquired businesses and technologies, 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 2003 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.