Label-Free Identification of Early Stages of Breast DuctalCarcinoma via Multiphoton Microscopy

Breast cancer can be cured by early diagnosis. Appropriate and effective clinical treatment benefits from accurate pathologicaldiagnosis. However, due to the lack of effective screening and diagnostic imaging methods, early stages of breast cancer oftenprogress to malignant breast cancer. In this study, multiphoton microscopy (MPM) via two-photon excitedfluorescencecombined with second-harmonic generation was used for identifying the early stages of breast ductal carcinoma. The resultsshowed differences in both cytological features and collagen distribution among normal breast tissue, atypical ductalhyperplasia, low-grade ductal carcinoma in situ, and high-grade ductal carcinoma in situ with microinvasion. Furthermore,three features extracted from the MPM images were used to describe differences in cytological features, collagen density, andbasement membrane circumference in the early stages of breast ductal carcinoma. They revealed that MPM has the ability toidentify early stages of breast ductal carcinoma label-free, which would contribute to the early diagnosis and treatment of breastcancer. This study may provide the groundwork for the further application of MPM in the clinic