Characterization of vascular patterns in endometrial cancer via optical resolution photoacoustic microscopy

We present a quantitative classification framework for endometrial pathology using optical resolution photoacoustic microscopy (OR-PAM). OR-PAM enables high-resolution, label-free imaging of capillary-scale microvasculature in freshly excised endometrial samples. We extracted vessel features—including diameter, heterogeneity, branching length, and photoacoustic signal frequency—that showed significant differences between normal and malignant cases. A logistic regression model with PCA achieved strong diagnostic separation (AUC = 0.92). Endometrial intraepithelial neoplasia (EIN) samples projected across both benign and malignant clusters, reflecting their transitional histologic status. These results highlight the potential of OR-PAM as a label-free optical biopsy tool for real-time gynecologic cancer diagnosis.