Abstract
To evaluate the efficacy of preoperative magnetic resonance imeging (MRI) (pre-MRI) in breast cancer surgery, the rates of intraoperative additional resection due to intraoperative frozen section analysis during breast-conserving surgery and the reoperation rates were compared in 2 groups of Japanese patients. In group 1 (99 cases in 2011), preoperative marking of the surgical margin was designated according to ultrasound (US) findings, while MRI findings were considered for designating the surgical margin in group 2 (112 cases in 2013). The rate of intraoperative additional resection of the mammary edge was 29.5% in group 2, which was significantly lower than 62.6% in group 1 (P<0.001). The rate of reoperation was also reduced from 5.1% (group 1) to 0.9% (group 2).
Pre-MRI was applied to only those patients who had planned partial resection (Bp) in group 1, but to all patients in group 2. Contralateral breast cancer was detected in 10 patients (2.5%) and the detection rates were not significantly different between the two groups.
The present results indicate that MRI findings could lead to an accurate resection range in breast-conserving surgery, thus contributing to the avoidance of reoperation.
