Magnetic Resonance Imaging in Breast Cancer Tissue In Vitro after PDT Therapy

Area of Science:

• Oncology
• Medical Imaging
• Biophysics

Background:

• Photodynamic therapy (PDT) is a growing treatment modality in medicine, particularly for breast cancer, the most prevalent cancer in women.
• Tumor characteristics, such as size (>10 mm), were considered for macroscopic assessment in this study.
• Quantitative non-contrast magnetic resonance imaging (MRI) offers a non-invasive method to evaluate tissue properties.

Purpose of the Study:

• To investigate the impact of PDT on breast cancer cells using quantitative non-contrast MRI.
• To evaluate changes in T1 and T2 relaxation times of breast cancer cells following PDT.
• To optimize a 1.5 T MRI system for analyzing these cellular changes.

Main Methods:

• Breast cancer tissues (tumors >10 mm) were analyzed using a 1.5 T GE Healthcare OPTIMA MR360 scanner.
• Quantitative T1 and T2 relaxation times were measured before and after PDT treatment using specific MRI sequences.
• MATLAB was utilized for image analysis of DICOM 3.0 standard MRI images, with statistical analysis including Shapiro-Wilk and t-tests.

Main Results:

• A significant reduction in both T1 and T2 relaxation times was observed in breast cancer cells after PDT.
• The pharmacological agent PpIX disodium salt and oxygen were used in conjunction with PDT irradiation.
• The observed decrease in relaxation times indicates a significant effect of PDT on tumor cells.

Conclusions:

• Quantitative non-contrast MRI can effectively detect changes in breast cancer cells post-PDT.
• PDT significantly impacts tumor cell properties, evidenced by reduced MRI relaxation times.
• This study highlights the potential of MRI-based relaxation time analysis for monitoring PDT efficacy in breast cancer.