Clinical Outcomes of Breast-Conserving Surgery in Patients Using a Modified Method for Cavity Margin Assessment

This study describes a modified intraoperative method for cavity margin (CM) assessment in place of lumpectomy margin assessment in patients undergoing breast-conserving surgery (BCS).This is a retrospective review of 422 breast cancer patients undergoing BCS with intraoperative CM assessment. After an initial lumpectomy with intent to obtain a parts per thousand yen1-cm margins, separate specimens 1 x 1 cm, 0.5-cm thick were taken from the cavity margin circumferentially. These were frozen without reference to the side of the new margin as a time-saving measure, and parallel sections of the resected surface were evaluated.After a median follow-up of 55.5 months, a cumulative 5-year locoregional recurrence-free survival rate of 95.3 %, metastasis-free survival rate of 97.8 %, disease-free survival rate of 88.3 %, and overall survival rate of 96.0 %, was achieved. The CM positivity rates were of no statistical difference when < 7, 7-8, and > 8 CMs were assessed. The second operation rate was 3.5 % because of the false-negative results of the frozen section analysis on CMs. Univariate and multivariate analysis revealed that a higher pN stage and cT stage as well as a lack of adjuvant chemotherapy or radiation demonstrated significantly worse clinical outcomes. Locoregional recurrences and metastasis are both correlated with worse overall survival. The number of the CMs assessed was not associated with clinical outcomes.The modified CM assessment presented here is a rapid, accurate, and oncologically safe approach for margin evaluation in BCS patients. Lumpectomy margin assessment might be spared when this method is used.

本研究描述了一种改良的术中腔缘（CM）评估方法，用于替代保乳手术（BCS）患者的肿块切除术切缘评估。这是一项对422例接受保乳手术且进行术中腔缘评估的乳腺癌患者的回顾性研究。在最初进行肿块切除术意图获得≥1厘米切缘后，从腔缘周围获取1×1厘米、0.5厘米厚的单独标本。作为一种节省时间的措施，在不参考新切缘方向的情况下对其进行冷冻，并对切除面进行平行切片评估。经过中位随访55.5个月后，累计5年局部区域无复发生存率为95.3%，无转移生存率为97.8%，无病生存率为88.3%，总生存率为96.0%。当评估<7个、7 - 8个和>8个腔缘时，腔缘阳性率无统计学差异。由于腔缘冷冻切片分析的假阴性结果，二次手术率为3.5%。单因素和多因素分析显示，较高的pN分期和cT分期以及缺乏辅助化疗或放疗表明临床预后明显更差。局部区域复发和转移都与更差的总生存相关。评估的腔缘数量与临床预后无关。此处介绍的改良腔缘评估是一种对保乳手术患者进行切缘评估的快速、准确且肿瘤学上安全的方法。当使用这种方法时，可能无需进行肿块切除术切缘评估。