乳腺浸润性导管癌磁共振弥散及动态增强多参数定量分析研究

目的 分析乳腺浸润性导管癌患者磁共振弥散加权成像（diffusion weighted imaging，DWI）及动态增强扫描的影像学特点。方法 收集经手术或穿刺病理确诊的乳腺浸润性导管癌患者32例，年龄31~77岁，平均年龄（56±11.60）岁，所有患者均行乳腺常规磁共振扫描（T1WI、T2WI）、DWI及动态增强扫描。分析32例患者扫描的磁共振图像，包括病变位置、DWI特点及表观扩散系数（apparent diffusion coefficient，ADC）值、病变强化形态及特点、动态增强曲线类型，计算信号增强比率（signal enhancement ratio，SER），采用受试者工作特征（receiver operating characteristic，ROC）曲线评估SER值的鉴别诊断价值，以P<0.05为差异有统计学意义。结果 病变主要发生在外上象限，共16例（50%），其次发生在内上象限，共7例（21.9%），乳头后方5例（15.6%），内下及外下象限3例（9.4%），不同区域多发1例（3.1%）。23例DWI信号升高，不均匀或环样升高7例，轻度升高2例。ADC值平均（0.910±0.231）×10^-3mm²/s，与患者对侧乳腺组织比较显著减低（P<0.001）。ROC曲线分析显示ADC的曲线下面积（area under the curve，AUC）为0.92，最佳诊断界值1.178×10^-3mm²/s，灵敏度81.3%，特异度90.6%。30例为肿块或结节样强化，可见分叶或毛刺征，2例为非肿块样强化。增强扫描后病灶边缘向心性强化或多发小环状强化30例，中心强化1例，明显均匀强化1例。增强曲线表现为流出型26例，平台型5例，渐进型1例。ROC曲线分析显示SER值的AUC为0.912，最佳诊断界值0.857，灵敏度96.8%，特异度83.9%。结论 乳腺浸润性导管癌患者病灶多发生在两上象限，以结节或肿块型为主，多见分叶及毛刺，DWI信号不同程度增高，ADC值减低，病灶早期强化明显，强化以边缘或多发小环形强化为主要特点。增强曲线以流出型最多见，SER值显著增高，有助于鉴别诊断。

Multi-parameters quantitative analysis of breast infiltrating ductal carcinoma as measured by diffusion weighted imaging and dynamic enhancement

Objective To analyze the imaging features of magnetic resonance diffusion weighted imaging (DWI) and dynamic enhanced scan in invasive ductal carcinoma of the breast. Methods Data of 32 cases of breast invasive ductal carcinoma confirmed by surgical operation or biopsy pathology were collected,the patients's age ranged from 31 to 77, average (56±11.60) years. All patients underwent routine breast magnetic resonance imaging (T1WI, T2WI), DWI and dynamic enhanced scanning. Images of the 32 patients were analyzed, including lesion location, DWI characteristics, apparent diffusion coefficient (ADC) values, morphological and characteristic of enhancement, and type of dynamic enhancement curve.The signal enhancement ratio(SER)was calculated. Receiver operating characteristic(ROC) curve was used to evaluate the diagnostic value of SER. The statistically significant differences were set at P<0.05. Results The lesions mainly located in the external upper quadrant, a total of 16 cases (50%), followed by the inner and upper quadrant, 7 cases (21.9%), 5 cases (15.6%) posterior to the nipple, 3 cases (9.4%) in the inferior and outer quadrant, 1 case (3.1%) of multifocal lesions in different regions. DWI showed 23 cases of hyperintense signal, 7 cases of uneven or ring-shaped hyperintense signals, and 2 cases of mild hyperintense signals. The mean ADC was (0.910±0.231)×10^-3 mm²/s, which was significantly lower than that of the contralateral breast tissue (P<0.001). ROC analysis showed that the area under the curve(AUC) of ADC was 0.92, the best diagnostic value was 1.178×10^-3mm²/s, the sensitivity was 81.3%, and the specificity was 90.6%. Lump or nodular enhancement was found in 30 cases,with lobulation or speculation, and 2 cases showed non mass like enhancement. Edge centrality enhancement or multiple small ring enhancement was found in 30 cases; addtionally,1 case of center enhancement and 1 case of homogeneous enhancement were also found. The dynamic enhancement curve showed outflow type in 26 cases, platform type of 5 cases, and progressive type of 1 case, with significant difference. ROC analysis showed that the AUC of ADC was 0.912, the best diagnostic value was 0.857, the sensitivity was 96.8%, the specificity was 83.9%.Conclusion Breast infiltrating ductal carcinoma lesions mainly located in the two upper quadrant, with nodule or mass type, irregular edges with lobulation and spiky change. DWI signals were elevated to varying degrees and ADC values decreased.The early obvious enhancement were revealed on the lesions, strengthening on the edge or small annular enhancement.The most common type of enhancement curves were the outflow type. The SER significantly increased, which was helpful for the differential diagnosis.