Investigation of synthetic MRI with quantitative parameters for discriminating axillary lymph nodes status in invasive breast cancer.

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Accurate staging of breast cancer is crucial for effective treatment planning.
• Axillary lymph node metastasis (ALNM) is a key prognostic factor in breast cancer.
• Conventional MRI has limitations in definitively assessing ALNM.

Purpose of the Study:

• To evaluate the utility of quantitative parameters from synthetic magnetic resonance imaging (syMRI) for discriminating ALNM in breast cancer patients.
• To compare the diagnostic performance of syMRI parameters between primary tumors and axillary lymph nodes.

Main Methods:

• Fifty-six female patients with invasive breast cancer underwent conventional MRI and syMRI.
• syMRI quantified T1 relaxation time (T1), T2 relaxation time (T2), and proton density (PD) in tumors and lymph nodes before and after contrast administration.
• Quantitative parameters and derived metrics (e.g., ΔT1, T1/T2) were analyzed using statistical tests and ROC analysis to assess ALNM discrimination.

Main Results:

• Lymph node short diameter (D_LN) was significantly larger in the ALNM group (10.22 mm vs. 5.28 mm, P < 0.001), with an AUC of 0.894.
• syMRI parameters T2_tumor, ΔT2_tumor, and ΔPD_tumor differed significantly between groups (P < 0.05), with T2_tumor showing the best discrimination (AUC = 0.712).
• syMRI parameters T1_LN, T2_LN, T1_LN/T2_LN, T2⁺_LN, and ΔT1_LN showed significant differences (P < 0.05). T1_LN was an independent predictor of ALNM (OR=1.426, P=0.039), with AUC of 0.785.

Conclusions:

• Quantitative syMRI parameters demonstrate value in discriminating ALN status in invasive breast cancer.
• T2_tumor exhibited the highest diagnostic efficiency among breast lesion parameters.
• T1_LN serves as an independent predictor for ALNM, highlighting its clinical significance.