Department of Radiation Oncology, University of Alabama at Birmingham Comprehensive Cancer Center, Birmingham, AL, USA.
Cancer. 2013 May 15;119(10):1776-83. doi: 10.1002/cncr.27995. Epub 2013 Feb 21.
Increased pathologic complete response (pCR) rates observed with neoadjuvant chemotherapy (NCT) for some subsets of patients with invasive breast cancer have prompted interest in whether patients who achieved a pCR can be identified preoperatively and potentially spared the morbidity of surgery. The objective of this multicenter, retrospective study was to estimate the accuracy of preoperative magnetic resonance imaging (MRI) in predicting a pCR in the breast.
MRI studies at baseline and after the completion of NCT plus data regarding pathologic response were collected retrospectively from 746 women who received treatment at 8 institutions between 2002 and 2011. Tumors were characterized by immunohistochemical phenotype into 4 categories based on receptor expression: hormone (estrogen and progesterone) receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative (n = 327), HR-positive/HER2-positive, (n = 148), HR-negative/HER2-positive, (n = 101), and triple-negative (HR-negative/HER2 negative; n = 155). In all, 194 of 249 patients (78%) with HER2-positive tumors received trastuzumab. Univariate and multivariate analyses of factors associated with radiographic complete response (rCR) and pCR were performed.
For the total group, the rCR and pCR rates were 182 of 746 patients (24%) and 179 of 746 patients (24%), respectively, and the highest pCR rate was observed for the triple-negative subtype (57 of 155 patients; 37%) and the HER2-positive subtype (38 of 101 patients; 38%). The overall accuracy of MRI for predicting pCR was 74%. The variables sensitivity, negative predictive value, positive predictive value, and accuracy differed significantly among tumor subtypes, and the greatest negative predictive value was observed in the triple-negative (60%) and HER2-positive (62%) subtypes.
The overall accuracy of MRI for predicting pCR in invasive breast cancer patients who were receiving NCT was 74%. The performance of MRI differed between subtypes, possibly influenced by differences in pCR rates between groups. Future studies will determine whether MRI in combination with directed core biopsy improves the predictive value of MRI for pathologic response.
新辅助化疗（NCT）在某些浸润性乳腺癌亚组中观察到的病理性完全缓解（pCR）率增加，促使人们关注是否可以在术前识别出达到 pCR 的患者，并有可能避免手术带来的发病率。本多中心回顾性研究的目的是估计术前磁共振成像（MRI）预测乳房 pCR 的准确性。
从 2002 年至 2011 年在 8 个机构接受治疗的 746 名女性中，回顾性收集基线和 NCT 完成后的 MRI 研究以及病理反应数据。根据受体表达，肿瘤通过免疫组织化学表型分为 4 类：激素（雌激素和孕激素）受体（HR）阳性/人表皮生长因子受体 2（HER2）阴性（n=327）、HR 阳性/HER2 阳性（n=148）、HR 阴性/HER2 阳性（n=101）和三阴性（HR 阴性/HER2 阴性；n=155）。共有 249 例 HER2 阳性肿瘤患者中的 194 例（78%）接受曲妥珠单抗治疗。对与放射学完全缓解（rCR）和 pCR 相关的因素进行单变量和多变量分析。
对于总组，rCR 和 pCR 率分别为 746 例患者中的 182 例（24%）和 746 例患者中的 179 例（24%），三阴性亚型（57 例/155 例；37%）和 HER2 阳性亚型（38 例/101 例；38%）的 pCR 率最高。MRI 预测 pCR 的总体准确率为 74%。变量敏感性、阴性预测值、阳性预测值和准确率在肿瘤亚型之间差异显著，三阴性（60%）和 HER2 阳性（62%）亚型的阴性预测值最大。
接受 NCT 的浸润性乳腺癌患者中，MRI 预测 pCR 的总体准确率为 74%。MRI 的性能在亚型之间存在差异，可能受不同组之间 pCR 率的差异影响。未来的研究将确定 MRI 与定向核心活检相结合是否可以提高 MRI 对病理反应的预测价值。
