Objective: To explore the diagnostic value of synthetic magnetic resonance imaging (syMRI) quantitative parameters for benign and malignant breast lesions. Methods: From September 2018 to March 2019, a total of 43 cases of breast lesions which were confirmed by surgery and pathology in Cancer Hospital, Chinese Academy of Medical Sciences were enrolled in this study. All patients underwent syMRI sequence scans before and after enhancement except for conventional T2WI, DWI, and enhancement scans. GE AW4.7 workstation was used to generate syMRI parameter maps (T1, T2, proton density mappings), and ITK-SNAP software was used to delineate the volume of interest. The T1, T2, PD values before and after dynamic contrast enhanced (DCE) were obtained, and the change values of each parameter were calculated. Meanwhile, the apparent diffusion coefficient (ADC) and time intensity curve (TIC) of the lesions were measured. The differences of each parameter value were compared between benign and malignant breast lesions, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic performance of each parameter. Results: Among the 43 enrolled cases, 13 were benign and 30 were malignant. Among the syMRI parameters, the pre-enhancement parameters including T1pre (median 1 663.07 ms), T2pre (median 103.33 ms), post-enhancement parameters ΔT1 (median 1 022.68 ms) and ΔT2 (median 27.67 ms) of benign group, significantly higher than those of the malignant group (the medians were 1 141.74, 92.53, 664.95, and 16.19 ms, respectively, P<0.05). The ADC value of the benign group (median 1.66×10(-3)mm(2)/s) was significantly higher than that of the malignant group (median 1.00×10(-3)mm(2)/s, P<0.05). The benign group included 6 cases of TIC curve type Ⅰ, 5 cases of type Ⅱ, and 2 cases of type Ⅲ. The malignant group included 2 cases of TIC curve type Ⅰ, 17 cases of type Ⅱ, and 11 cases of type Ⅲ. The difference between the two groups was statistically significant (P<0.05). The area under the ROC curve (AUC) of T1pre before DCE was 0.869, higher than 0.806 of ADC and 0.697 of TIC. When the best cut-off value of 1 282.94 ms was chosen, the sensitivity and specificity of diagnosis were 76.9% and 93.3%, respectively. The combination of T1pre and T2pre can further improve the diagnostic performance (AUC=0.908). Conclusions: Among the syMRI quantitative parameters, T1pre, T2pre, ΔT1 and ΔT2 have good value for the differential diagnosis of benign and malignant breast lesions. T1pre has the best diagnostic performance, and the combination of T1pre and T2pre can further improve the diagnostic performance.
目的： 探讨集成磁共振成像(syMRI)定量参数对乳腺良恶性病变的鉴别诊断价值。 方法： 2018年9月至2019年3月因乳腺肿物在中国医学科学院肿瘤医院就诊并经手术病理诊断的患者43例，除常规T2加权成像、扩散加权成像和增强扫描外，增强前后均行syMRI序列扫描。使用GE AW4.7工作站生成syMRI T1图、T2图和质子密度(PD)图，使用ITK-SNAP软件进行感兴趣区勾画，得出增强前后T1、T2和PD值，并计算各参数增强前后的变化值ΔT1、ΔT2和ΔPD，同时得到病变的表观弥散系数(ADC)和时间信号强度曲线(TIC)。比较良恶性病变间各参数值的差异，并采用受试者工作特征(ROC)曲线评估参数的诊断效能。 结果： 43例患者中，良性组13例，恶性组30例。syMRI参数中，良性组的增强前参数T1pre(中位数为1 663.07 ms)、T2pre(中位数为103.33 ms)、增强后参数ΔT1(中位数为1 022.68 ms)、ΔT2(中位数为27.67 ms)均高于恶性组(中位数为分别为1 141.74、92.53、664.95和16.19 ms)，差异均有统计学意义(均P<0.05)；良性组ADC值(中位数为1.66×10(-3)mm(2)/s)高于恶性组(中位数为1.00×10(-3)mm(2)/s，P<0.05)；良性组TIC曲线类型Ⅰ型6例、Ⅱ型5例、Ⅲ型2例，恶性组TIC曲线类型Ⅰ型2例、Ⅱ型17例、Ⅲ型11例，两组差异有统计学意义(P<0.05)。增强前T1pre的ROC曲线下面积(AUC)为0.869，高于ADC(AUC＝0.806)和TIC曲线类型(AUC＝0.697)，诊断效能最高。当T1pre取最佳界值为1 282.94 ms时，诊断的灵敏度为76.9%，特异度为93.3%，将T1pre和T2pre联合能够进一步提高诊断效能(AUC＝0.908)。 结论： syMRI定量参数中T1pre、T2pre、ΔT1和ΔT2对乳腺良恶性病变的鉴别诊断具有一定价值，其中T1pre诊断效能最佳，将T1pre和T2pre联合能进一步提高诊断效能。.
Keywords: Breast neoplasms; Diagnosis; Magnetic resonance imaging; Synthetic magnetic resonance imaging.