Diagnostic value of MRI for predicting axillary lymph nodes metastasis in newly diagnosed breast cancer patients: Diffusion-weighted MRI

ObjectiveNon-invasive preoperative detection of axillary nodal metastasis is beneficial for the outcome of breast cancer patients. We aimed to determine the value of DW MRI, ADC and their combination with MRI morphological criteria in detecting axillary metastasis.MethodsWe included recently diagnosed forty breast cancer patients. MRI morphological criteria, signal intensity on DWI, and ADC value were assessed and compared between metastatic and non-metastatic LNs using histopathological findings as reference standard. Sensitivity, specificity, PPV, NPV and accuracy for each variable and cutoff value of ADC were evaluated.ResultsNo statistically significant difference between metastatic and non-metastatic LNs in short axis diameter or L/S ratio (p value: 0.87 and 0.82 respectively); however, loss of fatty hilum, high signal intensity on DWI and low ADC value were significant with increasing sensitivity on their combination. The mean ADC was 0.96 ± 0.9 × 10−3 mm2/s for metastatic and 1.53 ± 0.6 × 10−3 mm2/s for benign LNs with cutoff value 1.09 × 10−3 mm2/s and sensitivity (94.5%), specificity (93.6%), PPV (96%), NPV (94.7%) and accuracy (95.6%).ConclusionDW-MRI and ADC per se or in combination with loss of the fatty hila is a promising and supportive tool for detection of axillary LNs metastasis.