Quest Diagnostics Incorporated , the nation's leading provider of diagnostic testing, information and services, and Enterix Inc., a privately held colorectal cancer screening company, today announced that they have entered into an agreement to offer InSure™, Enterix' proprietary, FDA-cleared test to detect human hemoglobin in fecal samples. Terms of the agreement were not disclosed.

Studies show that InSure, an immunochemical test, is a more accurate alternative to traditional guaiac-based fecal occult blood testing because it eliminates false positive test results due to the consumption of certain foods such as red meat or the use of common medications including aspirin. In addition, studies indicate that InSure provides 87% sensitivity for colorectal cancer detection and 97.8% specificity. InSure is a more patient-friendly screening test for the early detection of colorectal cancer. Unlike other colorectal cancer screening technologies, InSure is non-invasive and requires no handling of fecal matter.

The American Cancer Society's Guidelines for the Early Detection of Cancer, 2003, have been updated to reflect findings of a recently published article in CA: Cancer Journal for Clinicians,(1) which concluded that there is sufficient evidence to recommend fecal immunochemical testing for colorectal cancer screening and the early detection of adenomatous polyps in an average-risk population.

The new InSure technology provides increased accuracy and uncomplicated specimen collection that is easy for patients to perform at home. "We believe InSure is a significantly advanced colon cancer screening technology for patients," said Joyce Schwartz, M.D., Vice President and Chief Laboratory Officer of Quest Diagnostics. "Because specimen collection is easy and requires no fecal handling, we expect that patients will be more apt to use the test kit and return it for laboratory testing."

The current rate of patient adherence with recommended colorectal cancer screening guidelines -- using any method -- is lower than for screening tests for breast, cervical or prostate cancers. It is estimated that only 33% of Americans over the age of 50 have been screened for colorectal cancer by fecal occult blood testing within the past two years(2) -- versus 84% of American women over the age of 45 who have been screened for cervical cancer by Pap testing within the past three years.(3) For the 80 million people over the age of 50 who are of average risk, the American Cancer Society recommends annual colorectal cancer screenings. If detected and treated at an early stage, the 5-year relative survival rate for colorectal cancer is 90%.

"We look forward to collaborating with Quest Diagnostics," said Craig P. Sands, President and CEO of Enterix. "Quest Diagnostics' extensive distribution network and their substantial relationships with physicians provide an exciting opportunity to meet a currently unmet market need and save lives."

The test will be introduced early in the third quarter of 2003. Physicians and patients who are interested in learning more about InSure may visit www.enterix.com or www.questdiagnostics.com or may call Enterix toll-free at 800-531-3681, extension 10.

About Enterix

Enterix Inc. is dedicated to helping physicians and their patients screen for life threatening diseases such as cancer. The first product developed for Enterix' proprietary screening platform is the InSure Immunochemical Fecal Occult Blood Test, for the detection of early warning signs of colorectal cancer. Enterix has also identified and filed patent applications covering novel genomic markers that identify the development of pre-cancerous adenomatous polyps in the colon and rectum.

Founded in 1997, Enterix maintains operations in Falmouth, Maine, USA and in Sydney, Australia. Detailed information on Enterix can be found on the World Wide Web at www.enterix.com. Enterix can be reached at 1-800-531-3681 (USA), 1-800-55-65-75 (Australia) or by email at info@enterix.com.

About Quest Diagnostics

Quest Diagnostics Incorporated is the nation's leading provider of diagnostic testing, information and services, providing insights that enable healthcare professionals to make decisions that improve health. The company offers the broadest access to diagnostic testing services in the United States through its national network of laboratories and patient service centers, and provides interpretive consultation through its extensive medical and scientific staff. Quest Diagnostics is the leading provider of esoteric testing, including gene-based medical testing, and also empowers healthcare organizations and clinicians with state-of-the-art connectivity solutions that improve patient care. Additional company information is available at: http://www.questdiagnostics.com/ .

The statements in this press release which are not historical facts or information may be forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause actual results and outcomes to be materially different. Certain of these risks and uncertainties may include, but are not limited to, unanticipated expenditures, changing relationships with customers, suppliers and strategic partners, conditions of the economy and other factors described in the Quest Diagnostics Incorporated 2002 Form 10-K and subsequent filings.

  (1) CA Cancer J Clin 2003;53:44-55.

  (2) National Health Interview Survey, 2000, National Center for Health
      Statistics, Centers for Disease Control and Prevention, 2002 -
      American Cancer Society, Surveillance Research.

  (3) Data from the Centers for Disease Control's (CDC) Behavioral Risk
      Factor Surveillance System (BRFSS) for 2000 and 2001.

SOURCE: Quest Diagnostics Incorporated; Enterix Inc.

CONTACT: Investors and Media, Christopher Stamm of Enterix Inc.,
+1-781-684-0770; or Investors, Laure Park, +1-201-393-5030; or Media, Jennifer
Somers of Quest Diagnostics, +1-201-393-5700

Web site: http://www.questdiagnostics.com/
http://www.enterix.com/