Contact:  Robert Bowen, Chief Financial Officer
                                       Anne Rivers, Investor Relations
                                       Jeff Keene, Healthcare Media
                                       Cytyc Corporation: 978-266-3010
                                       www.cytyc.com
                                       -------------

                                       Robert P. Jones/Lauren Levine
                                       Media: Dan Budwick
                                       FD Morgen-Walke Associates: 212-850-5600

                                       Lloyd Benson/Shanti Skiffington
                                       Schwartz Communications:  781-684-0770



FOR IMMEDIATE RELEASE
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                     CYTYC CORPORATION ANNOUNCES INCREASE IN
                            STOCK REPURCHASE PROGRAM

Boxborough, MA, August 1, 2002 -- Cytyc Corporation (Nasdaq:CYTC) announced
today that its Board of Directors has authorized an additional $50 million for
the repurchase of shares of the Company's common stock through open market
purchases or private transactions that will be made from time to time as market
conditions allow. The Board of Directors also authorized the Company to
repurchase, on an ongoing basis, shares in addition to those to be purchased
with the $50 million that are equal in number to shares issued to option holders
upon exercise of their Company stock options. Today's authorization increases
the total amount of the repurchase program to $100 million plus the cost of
purchasing shares equivalent to the number of options exercised.

 A time limit of five years was set for the completion of the program. Shares
repurchased under the program will be held in the Company's treasury and will be
available for a variety of corporate purposes. The repurchase program may be
suspended at any time and from time to time without prior notice.

"Cytyc is committed to managing its capital for the benefit of its shareholders
and this expanded buyback program reflects our confidence in the Company's
future. This enhanced repurchase plan will also have the effect of neutralizing
stock option related dilution," said Patrick J. Sullivan, chairman and chief
executive officer of Cytyc Corporation.

"As of June 30, 2002, the company has $200.1 million in cash available, which we
expect to be sufficient to fund the repurchase program and continue to support
our core business objectives with respect to market penetration of the
ThinPrep(R) Pap Test(TM) and the launch of our proprietary ductal lavage
procedure for breast cancer risk assessment. Our current cash position and
strong projected cash flow allow us to continue to explore additional growth
initiatives," continued Mr. Sullivan.




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 and is a part of the S&P Midcap 400 Index and
The Nasdaq-100 Index.

Cytyc(R) and ThinPrep(R) are registered trademarks and ThinPrep(R) Pap Test(TM)
is a trademark of Cytyc Corporation.

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 regarding
management's plans and objectives for future operations, product plans and
performance, management's assessment of market factors, as well as statements
regarding Company 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, management
of growth, uncertainty of product development efforts, risks associated with the
FDA regulatory approval processes and any healthcare reimbursement policies,
risks associated with competition and competitive pricing pressures, 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 2001 Form 10-K 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.

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