Exhibit 99.1
                                                                   Press Release

Cytyc Corporation Denies All Allegations in Class Action Lawsuit

BOXBOROUGH, Mass. -- (BUSINESS WIRE) -- December 17, 2002 -- Cytyc Corporation
(Nasdaq: CYTC - News) today announced that a proposed securities class action
lawsuit was filed on December 13, 2002, in the United States District Court for
the District of Massachusetts against Cytyc and two of its officers. The
Complaint alleges that the defendants made materially inaccurate projections and
statements regarding the Company's prospects for generating revenue and income
in fiscal years 2002 and 2003.

Cytyc believes that the allegations are without merit and intends to defend
itself vigorously in this matter.

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(R) and ThinPrep(R) are registered trademarks of Cytyc Corporation.