The debate on how to select patients who will respond best to costly drug treatments for aggressive breast cancer now favors fluorescence in situ hybridization (FISH) to measure the HER-2 receptor found in human breast tumors, according to a leading pathologist presenting at the Association for Molecular Pathology annual meeting.
Michael Press, M.D., Ph.D., pathologist and Harold E. Lee Chair in Cancer Research, Norris Comprehensive Cancer Center, University of Southern California, told a symposium audience that a growing body of research in recent years demonstrates that FISH technology is an accurate, reproducible and predictive diagnostic method for testing women with breast cancer who are candidates for drug treatments targeted to the HER-2 tumor receptor. The drugs are Herceptin® (trastuzumab) and lapatinib. His remarks were presented at a symposium sponsored by Abbott Molecular.
HER-2 is a tumor marker for aggressive disease and to measure response to targeted therapies. The protein is a molecular target for the two medications, which suppress the HER-2 signal transduction pathway. For patients with HER-2-positive tumors, both drugs are clearly associated with improved clinical outcomes in metastatic breast cancer, and Herceptin is approved for use as adjuvant therapy.
Earlier this year, Press co-authored an article published in the Journal of Clinical Oncology refuting guidelines developed by the American Society of Clinical Oncology and the College of American Pathologists that recommended immunohistochemistry (IHC) as the preferred diagnostic method for determining a breast-cancer patient's HER-2 status.