Cancer Cell Identification in Tissue Imaging via Phasor Map Analysis in Polarization-resolved Two-Photon Excitation Fluorescence Microscopy

While cancer characteristics can vary significantly across types, methods that distinguish malignant cells from normal ones hold promise by targeting shared cellular anomalies. Among these, morphological differences play a key role in driving the aggressive behavior and altered function typical of cancer cells. Detecting and analyzing such cells within complex, densely packed tissue environments requires advanced imaging techniques. Polarization-resolved fluorescence microscopy offers rich insights into cellular composition, molecular binding affinities, and structural organization particularly in revealing biomolecular order and subcellular polarity loss. In this work, for the first time, we study polarization-resolved two-photon excitation fluorescence tissue imaging microscopy in-vitro to investigate ordered versus disordered chromatin organization within cell nuclei. We employ an innovative phasor map analysis to facilitate quick interpretation, using colorectal cancer identification and liquid crystal as a case study and baseline, respectively. Our method aims to assess new pathology labels within tissue by adding polarimetric contrast to fluorescence due to the anisotropic feature of fluorescent molecular probes. Accordingly, the proposed phasor map provides a graphically transformed representation of polarization-based fluorescence imaging for histopathological tissue identification on a pixel-wise basis, facilitating comprehensive classification of diverse tissue samples. This study presents initial steps toward showing the potential for cancer identification and lays a foundation for future diagnostic strategies.