WEDNESDAY, Jan. 16 (HealthDay News) -- A new genetic test that helps assess the risk of tumor recurrence and long-term survival for patients with relatively high-risk breast cancer has been approved by the U.S. Food and Drug Administration.

The TOP2A/FISH pharmDx is the first approved device to test for the TOP2A (topoisomerase 2 alpha) gene in cancer patients. The gene plays a role in DNA replication. Changes in the TOP2A gene in breast cancer cells indicate increased risk that a tumor will recur or decreased survival.

The new test, made by Dako Denmark A/S, uses fluorescently-labeled DNA probes to detect or confirm gene or chromosome abnormalities, a process called fluorescent in situ hybridization (FISH).

The FDA approval was based on a study of 767 high-risk patients in Denmark who had been treated with chemotherapy after removal of a breast tumor. The findings indicated the test was useful in estimating cancer recurrence and overall survival.

"When used with other clinical information and laboratory tests, this test can provide health care professionals with additional insights on the likely clinical course for breast cancer patients," Dr. Daniel Schultz, director of the FDA's Center for Clinical Devices and Radiological Health, said in a prepared statement.