乳腺叶状肿瘤的MRI表现分析

MR imaging analysis of phyllodes tumors of the breast

目的分析乳腺叶状肿瘤(PTs)的MRI表现。材料与方法回顾性分析经手术病理证实的10例PTsMRI表现,包括形态学、平扫信号强度、增强扫描病变内部强化特征及时间-信号强度曲线(TIC)类型、DWI信号及表观扩散系数(ADC)值。采用配对设计资料t检验比较PTs和正常乳腺组织ADC值的差异。结果 10例乳腺PTs术后病理诊断良性6例,交界性3例,恶性1例。MRI上6例表现为分叶状,4例为椭圆形;7例边界清晰,3例欠清;10例PTsMRI平扫T1WI均呈较低信号;T2WI脂肪抑制或STIR呈较高信号,其中2例肿瘤内见低信号分隔,2例见不规则囊性极高信号影;PTs于动态增强初始期呈快速强化,初始期后TIC2例呈Ⅰ型,8例呈Ⅱ型;9例行DWI检查,肿瘤均表现为高信号,平均ADC值为(1.32±0.18)×l0-3mm3/s;正常乳腺组织ADC值为(1.90±0.21)×l0-3mm3/s,二者差异有统计学意义(t=2.33,P<0.05)。结论乳腺PTs的MRI表现有一定的特点,但这些表现为非特征性,确诊仍需依靠组织病理学检查。

Objective： To analyse the MR imaging ofphyllodes tumors and improve the diagnosis level. Materials and Methods： The MRI data of 8 patients with phyllodes tumors of the breast verified by histopathology were analyzed. The MRI features analyzed included morphology, signal intensity on pre-enhanced T1WI, appearance of dynamic contrast enhancement （DCE-MRI）, the type of time-signal intensity curve （TIC）, and the features on DW1. The ADC values for phyllodes tumor and normal breast tissue were compared using paired t test. Results： The pathologic diagnosis of the 10 phyllodes tumors inclulding 6 benign, 3 borderline and 1 malignant. Of the 10 tumors, 6 were Iobular and 4 were oval in shape; the margins were well-defined in 7 cases, and ill-defined in 3 cases. All tumors were hypointensity on T1WI, and hyperintensity on T2Wl or STIR; Moreover, internal septations which appeared low signal intensity on T2WI in 2 tumors and hyperintense fluid-filled slit-like spaces in 2 tumors on T2WI FS or STIR were seen. On DCE-MRI, all of the tumors showed rapid initial enhancement, type I of TIC were shown in 2 cases and type Ⅱ in 8 cases. Nine patients underwent DWI were all showed high signal, the mean ADC value for phyllodes tumors [（1.32±0.18）×I0-3 mm3/s] was significantly lower than that of the nor- mal breast tissue[（1.90±0.21）×l0-3 mm3/s, t=2.33, P〈0.05]. Conclusion： The imagig findings ofphyllodes tumors on MR is characteristic but not specific, the final diagno- sis still depends on the histopathologic examination.