Breast Cancer Margin Delineation Using Polarization Subtraction Imaging Technology

LumaScan is an innovative polarization microscope that uses Polarization Subtraction Imaging (PSI) technology to provide real time, intra operative, digital images of the surface of tissue removed during BCS for breast cancer. PSI uses polarized visible light for optical sectioning and geometric imaging of the superficial layers of the surgically removed tissue while rejecting surface scatter and light from deeper layers. By rejecting light from deeper tissues PSI is able to exclusively focus on the superficial tissue layers. This also results in higher resolution images than are possible with standard optical imaging. PSI is used in both reflectance and fluorescence modes. Reflectance detects morphologic abnormalities that occur in tumor progression such as increased nuclear density, angiogenesis, cellular infiltration and crowding while fluorescence detects early biochemical changes. To enhance the contrast of tumor at the margins the investigators will use Methylene blue (MB), a dye that has been commonly used in breast surgery for mapping sentinel lymph nodes. MB can be administered peritumorally and is quickly taken up by cells in only a few minutes of exposure and its presence does not interfere with or preclude later histopathology on the same tissue specimen. A tumor specimen may also be dipped in MB post-excision to achieve tumor margin contrast enhancement and not interfere with pathologic assessment. Previous research using PSI technology has demonstrated the value of PSI in mapping tumor boundaries of breast cancer in excised tissue specimens and in non-melanoma skin cancers and these boundaries in side by side comparisons correlate well with those marked by a pathologist on representative sections prepared using standard H\&E staining procedures.