EXACT Sciences Announces Acceptance of Abstracts At Major Scientific Meetings.

Business Editors & Health/Medical Writers

BIOWIRE2K

MAYNARD, Mass.--(BW HealthWire)--Sept. 26, 2001

Abstracts further validate proprietary genomics-based technology

for detection of colorectal cancer

EXACT Sciences Corporation (NASDAQ: EXAS) announced today that abstracts submitted by the company and its collaborators to the American Society of Human Genetics (ASHG) and American College of Gastroenterology (ACG) have been accepted for presentation at the groups' respective annual meetings in October.

The abstracts provide further scientific evidence on the use of EXACT Sciences' DNA-based technologies for the non-invasive detection of colorectal cancer in stool. "We are pleased to continue to receive recognition and support from the scientific and medical communities," said Don Hardison, EXACT Sciences' President and CEO. "These works represent a significant advance in using EXACT Sciences' PreGen technology for the routine screening and surveillance of individuals at risk for developing colorectal cancer. As a greater number of people in the U.S. turn 50, the age the American Cancer Society recommends for the initiation of regular colon cancer screening, the need for tests that accurately detect cancer and that can best triage patients for colonoscopy is going to increase dramatically. We believe that our PreGen technology will provide a solution to this problem."

The first abstract, titled "Results of Stool BAT-26 Assay in People with HNPCC," has been accepted for presentation at the ASHG annual meeting to be held in San Diego, October 12-16. This abstract is the result of a collaboration between EXACT Sciences' scientific team, Henry Lynch, M.D. from Creighton University and Patrice Watson, Ph.D. from Creighton University. "The results of this study indicate that PreGen-26(TM) is useful as an adjunct to colonoscopy in screening people with the genetic syndrome known as Hereditary Non-Polyposis Colorectal Cancer," stated Dr. Lynch.

The second abstract, lead-authored by Dr. Randall E. Brand, an EXACT Sciences collaborator, has been accepted for presentation at the ACG annual meeting in Las Vegas on October 19-24. The abstract is titled "Stool DNA Mutation Testing for Colorectal Cancer Detection: Sensitivity and Reproducibility."

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 Maynard, Mass. Detailed information on EXACT Sciences can be found on the World Wide Web at www.exactsciences.com.

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements are subject to a variety of risks and uncertainties, many of which are beyond EXACT Sciences' control, which could cause actual results to differ materially from those contemplated in these forward-looking statements. In particular, the risks and uncertainties include, among other things, that the completion of clinical studies may not prove the superiority of EXACT Sciences' technologies, the failure to convince medical practitioners to order tests using EXACT Sciences' technologies, the loss of support of key scientific collaborators, the failure to comply with federal and state statutes and regulations relating to EXACT Sciences' products and services, including FDA requirements, and the operation of EXACT Sciences' laboratory, including the Clinical Laboratory Improvement Amendments, competition, the inability to protect EXACT Sciences' intellectual property and the cost of enforcing or defending EXACT Sciences in litigation relating to intellectual property rights. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. EXACT Sciences undertakes no obligation to update or revise the information contained in this press release, whether as a result of new information, future events or circumstances or otherwise. For additional disclosure regarding these and other risks faced by EXACT Sciences, see the disclosure contained in EXACT Sciences' public filings with the Securities and Exchange Commission including, without limitation, its Form 10-K for the year ended December 31, 2000 and subsequent Forms 10-Q.