肉芽肿性乳腺炎的MRI表现及鉴别诊断

Magnetic Resonance Imaging Findings and Differential Diagnosis of Granulomatous Mastitis

目的探讨肉芽肿性乳腺炎（GM）的磁共振动态增强及扩散加权成像特征,并研究其与浆细胞性乳腺炎和乳腺癌的鉴别诊断方法。方法回顾性分析经病理证实的21例GM、18例浆细胞乳腺炎和41例乳腺癌患者临床资料。所有患者均行乳腺磁共振动态增强扫描（DCE-MRI）及扩散加权成像。采用χ~2检验比较3组患者MRI图像特征,应用单因素方差分析法比较3组病变中心区、边缘区及平均ADC值差异。结果GM患者多为育龄期女性,浆细胞性乳腺炎常伴乳头溢液、疼痛及乳头内陷,乳腺癌发病年龄偏大。DCE-MRI显示肉芽肿性乳腺炎多为非肿块样病变、环形强化、边缘毛刺少见,与乳腺癌的形态、边缘及强化方式差异有统计学意义（χ~2值为26.473,47.230,39.685;P〈0.01）;GM乳腺内导管扩张少于浆细胞性乳腺炎,差异有统计学意义（χ~2值为8.171,P〈0.01）。GM脓肿中心区低于脓肿边缘区ADC值[ADC值为（0.89±0.23）×10^（-3）mm^2/s,（1.25±0.33）×10^（-3）mm^2/s,P〈0.01],GM脓肿中心区ADC值低于乳腺癌中心区ADC值[ADC值为（0.89±0.23）×10^（-3）mm^2/s,（1.22±0.29）×10^（-3）mm^2/s,P〈0.01]。结论GM的DCE-MRI特征性表现为环形强化,中心区ADC值低于边缘区。GM、浆细胞乳腺炎及乳腺癌的临床特点及MRI特征有利于三者的鉴别。

Objective To investigate the imaging characteristics of granulomatous mastitis（GM）in dynamic contrastenhanced magnetic resonance imaging（DCE-MRI）and diffusion weighted imaging（DWI）,and to study its differential methods with plasma cell mastitis and breast cancer.Methods 21 patients with GM,18 patients with PCM and 41 patients with breast cancer confirmed by pathology were retrospectively analyzed.All patients underwent breast dynamic contrast-enhanced MRI（DCE-MRI）and diffusion weighted imaging（DWI）.We analyzed the clinical characteristics of three groups of patients.χ~2test was used to compare MRI features of 3 groups patients.ADC values of lesion center,edge and average were analyzed by single factor variance analysis method.ResultsPatients with GM were usually women of childbearing age,Plasma cell mastitis was often associated with nipple discharge,pain and nipple crater,and the patients with breast cancer were largely elder women.Dynamic enhanced MRI scan revealed a non-mass lesion of GM with annular reinforcement,edge burr of lesion was rare,and there was statistical significance in the morphology,margin and enhancement patterns between GM and breast cancer（χ~2value were 26.473,47.230,39.685,P〈0.01）;while the ductal dilatation of granulomatous mastitis was less than plasma cell mastitis,there was statistically significant difference（χ~2value was 8.171,P〈0.01）.The ADC value of the abscess center in GM was lower than margin area（ADC value were 0.89±0.23,1.25±0.33,P〈0.01）,and ADC value of the abscess center in GM was lower than ADC value in breast cancer center（ADC value were 0.89±0.23,1.22±0.29,P〈0.01）.Conclusion Ring enhancement of GM was the characteristic finding in DCE-MRI,the center ADC value was lower than the margin of GM.The clinical characters and MRI features were useful in the differential diagnosis between GM,PCM and breast cancer.