Cytyc to Hold Earnings Call on October 28, 2004.

BOXBOROUGH, Mass. -- Cytyc Corporation (Nasdaq:CYTC) today announced plans to release its third quarter 2004 results on Wednesday, October 27, 2004, after the close of the market. In conjunction with the release, management will host a conference call on October 28 at 9:00 a.m. (Eastern). The call will be broadcast simultaneously over the Internet.

Interested participants may listen to a live webcast of the call from Cytyc's web site at http://ir.cytyc.com. Web participants are encouraged to go to the web site at least 15 minutes prior to the start of the call to register, download, and install any necessary audio software. Those without web access may contact Cytyc at 978-929-3322 for dial-in instructions to access the call.

After the live webcast, the call will remain available on Cytyc's web site, http://ir.cytyc.com, until November 12, 2004. A telephonic replay of the call will also be available through the same date by calling 973-341-3080 (Reservation No.: 5250137). International participants may use the same number and reservation number.

During the call, Patrick Sullivan, Cytyc Corporation's chairman, president, and chief executive officer; Daniel Levangie, executive vice president and chief commercial officer; Leslie Teso-Lichtman, vice president, controller, and acting chief financial officer; and John McDonough, senior vice president, development and operations, will provide an overview of the third quarter financial performance, business highlights, and future expectations.

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.