定量动态增强磁共振评估乳腺癌新辅助化疗疗效的应用研究

背景与目的：乳腺癌的新辅助化疗(neoadjuvant chemotherapy, NAC)已成为成熟的治疗方法，但疗效评估尚未有统一有效的方法。该研究即探讨定量动态增强磁共振在乳腺癌NAC疗效评估中的价值。方法：24例术前行NAC的乳腺癌确诊患者(24例均为浸润性导管癌)，分别于NAC前、第2个疗程后、化疗结束但术前3个时间点行定量动态增强磁共振检查，分析NAC前后肿瘤最长径及动态增强磁共振定量参数：容量转移常数(Ktrans)、速率常数(Kep)、血管外细胞外间隙容积比(Ve)的变化。结果：24例患者均为单侧单发乳腺癌病灶，以RECIST标准分为有效组(17个)和无效组(7个)，有效组与无效组Ktrans、Kep在NAC前与第2个疗程、化疗前与化疗结束差异均有统计学意义(P<0.05)，Ve在有效组与无效组治疗前后差异均无统计学意义(P>0.05)。结论：定量动态增强磁共振可用来评估NAC疗效，并且Ktrans、Kep可做到定量，使评估结果更为客观真实，但Ve对判断治疗效果未见明显优势。

Role of the dynamic contrast-enhanced MRI in assessing the response to neoadjuvant chemotherapy of breast cancer

Background and purpose:Neoadjuvant chemotherapy to breast cancer has become a mature treat-ment method. The purpose of this study was to evaluate the dynamic contrast-enhanced MRI in assessing the response to neoadjuvant chemotherapy (NAC).Methods:Twenty-four female patients with breast carcinoma (24 were all inva-sive ductal carcinoma) underwent dynamic contrast-enhanced MRI (DCE-MRI) before, after the second and ifnal cycle of NAC. For each patient and each MRI examination, the maximum diameter of tumor, volume transfer constant (Ktrans), exchange rate constant (Kep), and extravascular extracellular volume fraction (Ve) were compared. According to the method of response evaluation criteria in solid tumor (RECIST), the results of neoadjuvant chemotherapy were divided into responder and non-responder.Results:All 24 patients were unilateral and single breast cancer; there were 17 cases of responders and 7 cases of non-responders according to RECIST criteria. For 17 cases of responders, both the average values ofKtrans andKepwere signiifcantly descended after neoadjuvant chemotherapy (allP<0.05).Conclusion:The quantitative parameters ofKtrans andKep can evaluate objectively and veridically the response to neoadjuvant chemother-apy for breast cancer in dynamic contrast-enhanced MRI.