Polarization-dependent second-harmonic generation for collagen-based differentiation of breast cancer samples

Area of Science:

• Biophysics
• Optical Imaging
• Cancer Diagnostics

Background:

• Nonlinear optical imaging visualizes biological structures for diagnosis.
• Collagen orientation is crucial for understanding tissue mechanics and disease progression.

Purpose of the Study:

• To investigate collagen orientation in breast cancer tissues using polarization-dependent second-harmonic generation (PSHG).
• To evaluate PSHG imaging for quantitative assessment of tumor grade and differentiation between benign and malignant tissues.

Main Methods:

• Utilized polarization-dependent second-harmonic generation (PSHG) imaging on breast cancer biopsy tissues (grades 0-III).
• Processed data with fast Fourier transform (FFT) analysis, calculating second-harmonic generation (SHG) anisotropy and ratio parameters.

Main Results:

• PSHG measurements successfully distinguished collagen structure modifications across different cancer grades.
• Calculated SHG anisotropy and ratio parameters correlated with mechanical tension during cancer progression.

Conclusions:

• PSHG imaging offers a quantitative method for evaluating tumor state and distinguishing malignant from benign breast tissues.
• This approach enables the development of label-free, nondestructive optical diagnostic tools for improved cancer detection and reduced biopsies.