Quest Diagnostics Incorporated , the nation's leading provider of diagnostic testing, information and services, announced today that it has signed an agreement with Veridex, LLC, a Johnson & Johnson company, to be the only national commercial reference laboratory to offer a test using Veridex's CellSearch™ Circulating Tumor Cell Kit, a new cancer diagnostic technology that identifies and counts circulating tumor cells in blood samples from patients being treated for metastatic breast cancer. The test will be available later this month to physicians nationwide through Quest Diagnostics Nichols Institute, the company's esoteric testing laboratory, in San Juan Capistrano, California. Terms of the agreement were not disclosed.

"This important new test has the potential to help oncologists better care for patients with metastatic breast cancer," said Surya N. Mohapatra, Ph.D., President and Chief Executive Officer at Quest Diagnostics. "We are excited to offer this test, which strengthens our position in oncology testing as a trusted resource for doctors and their patients."

Results of a prospective, multi-center study published August 19, 2004, in the New England Journal of Medicine(1) demonstrated that the number of circulating tumor cells is predictive of progression free survival and overall survival in metastatic breast cancer patients.

Veridex received clearance from the U.S. Food and Drug Administration in January, 2004, for the CellSearch™ Epithelial Cell Kit to be used for the enumeration of circulating tumor cells of epithelial origin in whole blood.

Circulating tumor cells are present in the blood when a primary cancer sheds tumor cells into the circulatory system. Cancer metastasis occurs when circulating tumor cells begin to grow in distant locations in the body. The ability to identify and count circulating tumor cells has the potential to improve the ability of oncologists to care for their patients with metastatic breast cancer.

Knowing the number of circulating tumor cells in the blood may help oncologists make decisions about patients' treatment earlier than previously possible. Until now, physicians had to wait three months or longer before they could determine if a specific treatment was beneficial to the patient.

For more information about CellSearch™ Circulating Tumor Cells, physicians can call Quest Diagnostics Nichols Institute toll-free at 800-642-4657, extension 2906.

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 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 provides advanced information technology solutions to improve patient care. Additional company information is available at: http://www.questdiagnostics.com/

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, competitive environment, changes in government regulations, changing relationships with customers, payers, suppliers and strategic partners and other factors described in the Quest Diagnostics Incorporated 2003 Form 10-K and subsequent filings.

CellSearch is a trademark of Veridex, LLC, a Johnson & Johnson company. All other trademarks are property of their respective owners.

  (1) Cristofanilli, M, Budd, GT, Ellis, MJ, et al.  Circulating Tumor
      Cells, Disease Progression, and Survival in Metastatic Breast Cancer.
      N Engl J Med. 2004; 351:781-791.

SOURCE: Quest Diagnostics Incorporated

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