Cytyc Corporation Files Registration Statement for Resale of 2.25% Convertible Notes Due 2024.

Business Editors/Health/Medical Writers

BOXBOROUGH, Mass.--(BUSINESS WIRE)--June 9, 2004

Cytyc Corporation ("Cytyc") (Nasdaq: CYTC) today announced that it has filed a registration statement on Form S-3 with the Securities and Exchange Commission (the "SEC") relating to the resale of $250 million aggregate principal amount of its 2.25% Convertible Notes due 2024 (the "Notes") and the shares of its common stock issuable upon conversion of the Notes. The Notes were originally issued in a private placement in March 2004.

When declared effective by the SEC, the registration statement will be available for use by the holders named therein to resell the Notes and the shares of Cytyc common stock issuable upon conversion of the Notes.

Cytyc will not receive any proceeds from the sale by any selling securityholder of the Notes or the shares of Cytyc common stock issuable upon conversion of the Notes.

When available, a copy of the prospectus (as supplemented) may be obtained from:

    Suzanne Meszner-Eltrich
    Senior Vice President, General Counsel and Secretary
    Cytyc Corporation
    85 Swanson Road
    Boxborough, MA 01719

The registration statement relating to these securities has been filed with the SEC but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any State in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such State.

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, NovaSure, and FirstCyte are registered trademarks of Cytyc Corporation.