Clinical Significance of Non-Mass-Like Enhancement of Preoperative Magnetic Resonance Imaging in Breast Cancer Considering Breast-Conserving Surgery

ABSTRACT

PURPOSE: The purpose of this study was to investigate the significance of non-mass enhancement (NME) findings on preoperative breast magnetic resonance imaging (MRI) when invasive breast cancer patients with single lesions underwent breast-conserving surgery (BCS). METHODS: We reviewed the preoperative MRI findings of 252 patients who underwent BCS from January 2014 to September 2016. Based on the MRI findings, we divided the patients into two groups, those who did and did not have NME, and we retrospectively analyzed the clinical outcomes of the two groups. RESULTS: The NME group had 57 patients, and the no-NME group had 195 patients. The incidence of in situ lesions was higher in the NME group than in the no-NME group (p<0.001). Additionally, the positive resection margin rate on frozen biopsy was higher in the NME group than in the no-NME group (p=0.002). CONCLUSION: When preoperative MRI had NME findings, in situ lesions were more likely to accompany invasive breast cancer lesions, and the positive resection margin rate for frozen biopsy during BCS was high. Therefore, in these cases, the lesion should be excised more widely when BCS is performed, or frozen biopsy for resection margin during BCS should be performed if possible.