Monitoring adipose tissue invasion in breast cancer by multiphoton microscopy

Adipocytes are considered to be a critical cell type in the tumor microenvironment of breast cancer. Many studies have confirmed that adipocytes are not only found adjacent to cancer cells, but they also play an active role in the entire process of cancer development, progression, metastasis, and treatment response in breast cancer. Adipose tissue invasion (ATI) is a way of tumor cell metastasis, which not only indicates the poor prognosis of patients but also indicates the decline of survival rate. Multiphoton microscopy (MPM) with subcellular resolution based on second harmonic generation (SHG) and two-photon excited fluorescence (TPEF) is very suitable for real-time detecting morphological and structural changes in biological tissues without tissue staining and exogenous probe molecule. In this study, MPM was applied to identify the adipose tissue invasion in breast cancer patients. The results indicated that it is feasible to detect adipose tissue invasion with multiphoton microscopy, and to provide a new auxiliary tool for pathologists to quickly and effectively diagnose adipose tissue invasion.