High-Speed Intraoperative Assessment of Breast Tumor Margins Using a Multimodal Vibrational Photoacoustic Tomography System

Breast cancer is the most common invasive cancer for women. About 1 in 8 women will develop breast cancer in their lifetime. As the prevalence of breast cancer screening, more lesions are identified in an early stage, leading to the popularity of using breast-conserving surgeries or lumpectomy. Therefore, achieving a negative or clear margin is essential for the clinical outcomes. However, an unmet need still exists to achieve time-efficient and highly-sensitive intraoperative evaluation of breast cancer margins during surgical procedures. Photoacoustic tomography, inherently compatible with ultrasound, provides chemical specific contrast and centimeter penetration depth with high-speed. Thus it offers a compelling way for breast tumor margins evaluation intraoperatively. In this dissertation, I demonstrated a compact, automatic intraoperative breast tumor margins assessment using a multimodal vibration-based photoacoustic tomography system. This system can provide \u3e 3mm tissue depth, and three-dimensional compositional information of the entire excised breast tissue within 10 minutes. With the system, 40 frozen-thawed breast tumor tissues were imaged, showing a 93% sensitivity and 90% specificity in margin assessment when cross-correlated with standard histology. Such results present the potential of using vibration-based photoacoustic tomography as a high-speed and accurate method for intraoperative breast tumor margins evaluation in breast-conserving surgeries. At present, the system is in Indiana University Health Simon Cancer Center for clinical validation. We expect to recruit 107 patients to this study. Further clinical studies will need to be conducted to validate the system for high-throughput and user-friendliness