乳腺小体积叶状肿瘤与纤维腺瘤的MRI鉴别诊断价值

Differential diagnostic value of MRI in breast small volume phyllodes tumor and fibroadenoma

目的分析乳腺小体积叶状肿瘤的MRI特征,探讨MRI对小体积叶状肿瘤与纤维腺瘤的鉴别诊断价值。方法选择经MRI扫描乳腺肿瘤患者74例,均为女性,年龄24～64岁,平均年龄43岁;其中叶状肿瘤25例,纤维腺瘤49例。叶状肿瘤患者,年龄35～64岁,平均年龄57岁;肿瘤直径1.76～4.78 cm。纤维腺瘤患者,年龄24～57岁,平均年龄42岁;肿瘤直径1.64～4.89 cm。分别分析其MRI表现[病灶形态边缘、信号强度、病灶内囊腔形成、T_2加权成像(T_2WI)低信号间隔、增强后强化特点和时间-信号强度曲线(TIC)],并进行统计学分析,比较两组间差异。结果 25例叶状肿瘤共25个病灶,经病理证实良性14例,交界性7例,恶性4例。49例纤维腺瘤共56个病灶。叶状肿瘤多表现为边缘分叶状肿块(19/25,76.00%),信号特点主要为T_1加权成像(T_1WI)低、T_2WI高信号为主(21/25,84.00%),部分叶状肿瘤患者伴有斑片状T_1WI高信号(6/25,24.00%)、小囊变(14/25,56.00%)及T_2WI低信号间隔(15/25,60.00%),增强后多为不均匀强化(18/25,72.00%),TIC分型多为Ⅱ型(12/25,48.00%)。纤维腺瘤部分表现为边缘分叶状肿块(32/56,48.21%),T_1WI低、T_2WI高信号为主(43/56,76.79%),部分病灶内有小囊腔(16/56,28.57%)、低信号间隔(24/56,42.86%)及斑片状T_1WI高信号(3/56,5.36%),增强后不均匀强化(27/56,48.21%),TIC分型多为Ⅰ型(34/56,60.71%)。叶状肿瘤病灶内出现小囊腔及T,WI斑片状高信号比例与纤维腺瘤相比,差异有统计学意义(P<0.05);其余征象二者未见明显差异。结论 MRI能提高对乳腺小体积叶状肿瘤与纤维腺瘤的鉴别诊断。

Objective To analyze MRI features of breast small volume phyllodes tumor, and explore the value of MRI in differential diagnosis between small volume phyllodes tumor and fibroadenoma. Methods A total of 74 female patients with breast tumor were enrolled, which aged 24-64 years old with mean age of 43 years old. Of all the patients, 25 cases with phyllodes tumor(aged 35-64 years old with mean age of 57 years old;tumor diameter was 1.76-4.78 cm) and 49 cases with fibroadenomas(aged 24-57 years old with mean age of 42 years old;tumor diameter was 1.64-4.89 cm). The MRI findings[lesion morphology, signal intensity, intracapsular formation, T2 weighted imaging(T2WI) low signal interval, enhanced post-enhancement characteristics and time-signal intensity curve(TIC)] were analyzed, and statistical analysis were performed to compare the differences between 2 groups. Results There were 25 lesions in 25 cases of breast phyllodes tumor. The pathologic findings indicated 14 cases of benign, 7 cases of borderline, and 4 cases of malignant tumor. There were 56 lesions in 49 cases of fibroadenoma. The mostly phyllodes tumor showed marginal phyllodes(19/25, 76.00%), characteristics of signal were hypointensity on T1 weighted imaging(T1WI) and hyperintensity on T2WI(21/25, 84.00 %). Some lesions showed hyperintensity on T1WI(6/25, 24.00 %), small cysts(14/25, 56.00 %) and low signal interval on T2WI(15/25, 60.00 %). Mostly uneven reinforcement after enhancement(18/25, 72.00 %), and most of TIC was type Ⅱ(12/25, 48.00 %). The breast fibroadenoma exhibited marginal phyllodes(32/56, 48.21 %), the signal characteristics were hyperintensity on T1WI and hypointensity on T2WI(43/56,76.79 %). Some lesions were accompanied with small cysts( 16/56, 28.57 %), low signal interval on T2WI(24/56, 42.86 %) and hyperintensity on T1WI(3/56, 5.36 %), with uneven enhancement(27/56, 48.21 %). Most of TIC was type Ⅰ(34/56, 60.71 %).The proportion of small cysts and hyperintensity on T1WI in breast phyllodes tumor were significantly higher than that in fibroadenoma(P< 0.05), and there were no significant differences in other signs between 2 groups. Conclusion It is demonstrated that MRI is valuable in differentiating small phyllodes tumor from fibroadenoma of the breast.