Diffusion tensor imaging and diffusion-weighted imaging on axillary lymph node status in breast cancer patients

Area of Science:

• Radiology and Medical Imaging
• Oncology
• Biophysics

Background:

• Accurate assessment of axillary lymph node (ALN) status is crucial for breast cancer staging and treatment planning.
• Conventional imaging methods may have limitations in definitively identifying ALN metastases.

Purpose of the Study:

• To evaluate the effectiveness of diffusion tensor imaging (DTI) and diffusion-weighted imaging (DWI) in assessing axillary lymph nodes (ALN) in breast cancer patients.
• To compare the diagnostic performance of DTI/DWI metrics with morphological features for ALN metastasis detection.

Main Methods:

• Diffusion tensor imaging (DTI) and diffusion-weighted imaging (DWI) were performed on 66 breast cancer patients.
• Morphological features, apparent diffusion coefficient (ADC), volume anisotropy, and fractional anisotropy were measured for the largest ALN with increased cortical thickness.
• Imaging findings were correlated with histopathological results.

Main Results:

• Metastatic ALN were detected in 65.1% of patients.
• Metastatic ALN showed significantly higher cortical thickness and lower long-axis-to-short-axis ratio compared to non-metastatic ALN.
• Apparent diffusion coefficient (ADC) values were significantly lower in metastatic ALN (97.7% sensitivity, 91.3% specificity).
• Fractional anisotropy and volume anisotropy values also differed significantly between metastatic and non-metastatic ALN.

Conclusions:

• Apparent diffusion coefficient (ADC) values are significantly lower in metastatic ALN compared to non-metastatic ALN.
• DTI-derived metrics, particularly ADC, demonstrate superior diagnostic performance over morphological features for ALN metastasis.
• DTI metrics show potential to complement breast MRI for ALN assessment, pending standardization of imaging parameters.