High‐speed intra‐operative assessment of breast tumour margins by multimodal ultrasound and photoacoustic tomography

Abstract

Conventional methods for breast tumour margins assessment need a long turnaround time, which may lead to re‐operation for patients undergoing lumpectomy surgeries. Photoacoustic tomography ( PAT ) has been shown to visualize adipose tissue in small animals and human breast. Here, we demonstrate a customized multimodal ultrasound and PAT system for intra‐operative breast tumour margins assessment using fresh lumpectomy specimens from 66 patients. The system provides the margin status of the entire excised tissue within 10 min. By subjective reading of three researchers, the results show 85.7% [95% confidence interval ( CI ), 42.0–99.2] sensitivity and 84.6% (95% CI , 53.7–97.3) specificity, 71.4% (95% CI , 30.3–94.9) sensitivity and 92.3% (95% CI , 62.1–99.6) specificity and 100% (95% CI , 56.1–100) sensitivity and 53.9% (95% CI , 26.1–79.6) specificity, respectively, when cross‐correlated with post‐operational histology. Furthermore, a machine learning‐based algorithm is deployed for margin assessment in the challenging ductal carcinoma in situ tissues and achieved 85.5% (95% CI , 75.2–92.2) sensitivity and 90% (95% CI , 79.9–95.5) specificity. Such results present the potential of using multimodal ultrasound and PAT as a high‐speed and accurate method for intra‐operative breast tumour margins evaluation.