The GeneSearch BLN Assay test specifically detects molecules that are abundant in breast tissue but are scarce in normal lymph nodes.
Being able to see the presence of breast cancer cells in the lymph nodes of the underarm is a strong predictor of whether or not cancer has spread, according to the FDA.
Lymph nodes help to protect the body from infections and they are the first place where breast cancer cells are likely to spread.
"The GeneSearch BLN Assay offers a new approach to ... testing," said Daniel Schultz, MD, director of the FDA's Center for Devices and Radiological Health.
"Results of this rapid test are available while patients are on the operating table, providing a way for some women to avoid a second operation," added Schultz.
A clinical trial proved the GeneSearch BLN Assay test to be accurate in predicting whether breast cancer had spread in nearly 88 percent of the women with metastasis. The test was accurate in predicting those patients who did not have metastasis in 94 percent of the women.
When the GeneSearch BLN Assay test was compared during surgery by immediate microscopic examinations, the test resulted in fewer false negatives but slightly greater false positives. Therefore, additional testing may be quite helpful.
The GeneSearch BLN Assay test is manufactured by Veridex, a Johnson & Johnson Company.
