Blood test detects genetic changes in progressive disease.

2004 JUL 1 - (NewsRx.com & NewsRx.net) -- Researchers at the University of Texas (UT) Southwestern Medical Center at Dallas have developed a blood test that can detect amplification of a certain gene found in circulating cells associated with breast cancer.

If further clinical studies bear out its effectiveness, researchers say the blood test could be used as a standard operating procedure to monitor genetic changes for which a treatment is available.

"Cancer is a moving target, and the oncologist has to know which bullet to put in his gun," said Jonathan Uhr, professor of microbiology and internal medicine in the Cancer Immunobiology Center at UT Southwestern and senior author of the study. "Obtaining repeated blood samples is a safe and routine procedure, and this test can help the oncologist determine whether a new genetic change has become dominant and calls for a specific treatment for that change."

The work is scheduled to appear in an upcoming issue of the Proceedings of the National Academy of Sciences USA and is currently available online.

The researchers developed a blood test to optimize the detection and characterization of circulating cancer cells shed from a primary tumor. This is done by matching the cells' genetic abnormalities with the parent tumor.

The test can detect one circulating tumor cell in 10 million white blood cells, said Uhr.

The research augments previous work by UT Southwestern researchers to determine if patients whose primary tumor did not have amplification of the gene HER-2 could acquire amplification if the tumor recurred and progressed. Using the new blood test to examine the circulating tumor cells from growing tumors, initial indications are this amplification eventually can occur, Uhr said.