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                                                                 EXHIBIT 99.1

MARLBOROUGH, MASS. -- JULY 14, 2003 -- EXACT Sciences Corporation (NASDAQ:
EXAS) announced today that it will host a conference call for its second
quarter 2003 financial and operating results on Tuesday, July 22, 2003 at
8:30 a.m. EDT.  A live Webcast of the conference call can be accessed at
www.exactsciences.com through the Investor Relations link.  The conference
call and the Webcast are open to all interested parties.  An archived version
of the Webcast will be available at EXACT Sciences' Web site,
www.exactsciences.com, through the Investor Relations link, for one month.  A
replay of the conference call also will be available for 48 hours, following
the completion of the live call.

EXACT Sciences will announce its second quarter 2003 financial and operating
results on Monday, July 21, 2003, after the close of regular market trading
hours.

Information for the call is as follows:

Domestic callers:       877-809-1575

International callers:  706-679-5918

Conference ID #         1649075

The conference call replay information is as follows:

Domestic callers:       800-642-1687

International callers:  706-645-9291

Conference ID # 1649075

The webcast is also being distributed over CCBN's Investor Distribution
Network to both institutional and individual investors.  Individual investors
can listen to the call through CCBN's individual investor center at
www.companyboardroom.com or by visiting any of the investor sites in CCBN's
Individual Investor Network. Institutional investors can access the call via
CCBN's password-protected event management site, StreetEvents
(www.streetevents.com).

ABOUT EXACT SCIENCES CORPORATION

EXACT Sciences Corporation is an applied genomics company that has developed
proprietary technologies that may be used for the early detection of several
common cancers.  EXACT Sciences has selected colorectal cancer as the first
application of its technologies.  Colorectal cancer is the most deadly cancer
among non-smokers, and is curable if detected early.  Despite the availability
of colorectal cancer screening and diagnostic tests for more than 20 years, the
rate of early detection of colorectal cancer remains low.  EXACT Sciences
believes its genomics-based technologies will enable early detection of
colorectal cancer so that more people can be effectively treated.  Founded in
1995, EXACT Sciences is based in Marlborough, Mass.  Detailed information on
EXACT Sciences can be found on the World Wide Web at www.exactsciences.com.

CONTACT:
Media Contact
Peggy Kochenbach, 617.267.8223
kochenbp@fleishman.com
or
Investor Relations
Amy Hedison, 508.683.1252
ahedison@exactsciences.com