FDA Okays Molecular Assay to Detect Node-Positive Breast Cancer

ROCKVILLE, Md., July 16 -- The FDA has approved a rapid molecular-based test for detecting node-positive breast cancer.

The FDA said the approval of GeneSearch BLN assay marked the first molecular-based technology to determine while a woman was still in the OR whether the disease was node-positive

Daniel Schultz, M.D., director of the FDA's Center for Devices and Radiological Health said the assay "offers a new approach to sentinel node testing."

It is common practice to remove the sentinel node for examination during lumpectomy or mastectomy. In some cases the node is examined immediately and additional nodes are removed if cancer cells are found in the sentinel node. That initial exam is followed by more complete pathology that typically takes one to two days.

For some women, cancer cells are only discovered during the later examination. In those cases women may need additional surgery.

In a clinical trial, the GeneSearch BLN Assay showed strong agreement with results from extensive pathology of the nodes of 416 patients. The test accurately predicted that breast cancer had spread nearly 88% of the time in women with metastasis. Patients without metastasis were identified accurately 94% of the time.

When BLN Assay results were compared with immediate microscopic examination during surgery, there were fewer false negative results, but there were slightly more false positives. A false positive test, indicating nodal spread when there was none, could result in a more extensive surgery and increased the risk of lymphedema and other side effects, the FDA said.