Polarized photoacoustic imaging for cell division state recognition and tumor assessment.

Rapid assessment of tumor proliferation and malignancy is critical for intraoperative margin guidance. However, conventional Hematoxylin and Eosin (H&E)-stained images and fluorescence imaging require extensive sample preparation, limiting real-time applications. Here, we propose a label-free deep ultraviolet polarization photoacoustic imaging technique for identifying mitotic states and assessing tumor aggressiveness through sensitivity to microstructural anisotropy. Following theoretical modeling and system development, cell and tissue experiments demonstrated distinct polarization-dependent responses associated with mitotic structural changes. The results indicate that this approach enables stain-free mapping of proliferative activity and tumor microstructural features, showing potential for rapid tumor evaluation and future applications.