Prediction of pathological margin status using preoperative contrast‐enhanced MRI MRI in patients with early breast cancer who underwent skin‐sparing mastectomy

摘要

Abstract Skin‐sparing mastectomy ( SSM ) with immediate reconstruction is standard surgical treatment for early breast cancer with widespread ductal carcinoma in situ ( DCIS ). The local recurrence rate after SSM is up to 7.0%. We investigated prediction of the pathological margin using contrast‐enhanced MRI , and evaluated the cut‐off point to obtain the safety margin. We performed SSM with immediate reconstruction in 216 early breast cancer patients with widespread DCIS and/or invasive cancer from January 2014 to December 2015. Forty cases were retrospectively reviewed after excluding those with 15?mm between skin and tumor, determined by preoperative contrast‐enhanced MRI , or involving reconstructive surgery for local recurrence, immeasurable lesion by preoperative contrast‐enhanced MRI , or neoadjuvant chemotherapy. We defined a positive pathological margin as 1?mm from the cancer nest. We reviewed the distance between skin and tumor by MRI and pathological examination. To identify the cut‐off for predicting a positive pathological margin, we performed sensitivity analysis using an ROC curve. The margin‐positive rate by pathological examination was 27.5% (n?=?11/40), with a moderate correlation of MRI margin and pathological margin (r?=?0.44). The best cut‐off point for margin positivity was 5?mm of MRI margin, with sensitivity and specificity of 54% and 86%, respectively ( P? = ? 0.009). This is the first prediction of pathological margin by preoperative contrast‐enhanced MRI in early breast cancer patients with SSM . Care is required for SSM if the MRI margin is less than 5?mm due to pathological margin positivity.