Semi-automated imaging system to quantitate Her-2/neu membrane receptor immunoreactivity in human breast cancer.

Background: Immunocytochemical methods for quantitating Her-2/neu immunoreactivity rest on subjective semi-quantitative interpretations with resulting interobserver, intraobserver, and fatigue variability.

Methods: To standardize and quantitate measurements of Her-2/neu immunoreactivity, we created epithelial-recognition and specific membrane-recognition algorithms, which could image breast cancer cells against a background of stroma, compartmentalize the cancer cell into nucleus, cytoplasm and membrane, and quantitate the degree of Her-2/neu membrane immunoreactivity based on both gray scale intensity and RGB colorimetric determinations. Image acquisition utilized either scanner or microscope with attached camera with a resolution of 20 pixels/10 microm.