颅内孤立性纤维性肿瘤的MRI征象与病理对照

MRI features of intracranial solitary fibrous tumors compared with pathological findings

目的探讨颅内孤立性纤维性肿瘤(intracranial solitary fibrous tumor,ISFT)的MRI特征,并与病理对照,以提高对其MRI诊断及鉴别诊断能力。方法对我院2012年5月~2017年2月经手术病理证实的6例ISFT患者的MRI、临床及病理资料进行回顾性分析,男4例,女2例,年龄45~73岁,平均59.67岁。结果本组6例肿块最大径2.5~6.3cm,均具有颅内脑外肿瘤特点:1)发病部位:左额部1例,右顶枕部1例,右顶后部1例,左侧跨越小脑幕生长者1例,左侧额顶部镰旁1例,延髓左后方1例;2)MRI表现:所有肿块以圆形、类圆形为主并灶周水肿,局部分叶致肿块外形不规则。信号不均,5例以稍长/等T1、不均质长T2信号为主,内部见T2WI低信号区,增强扫描该T2WI低信号区明显强化;1例为短T1短T2信号。2例见"脑膜尾征",1例病灶内见粗大迂曲血管;3)病理及免疫组化:镜下均为梭形细胞肿瘤,免疫组化:Vim(+^++),CD34++,bcl-2(+^++)/(-),CD99(+^++),Ki67+(增殖指数<10%),EMA(-),S-100(-),SMA(-),GFAP(-)。结论 ISFT的MRI表现具有一定特征性,是其病理基础的必然反映,有助于术前正确诊断。

Objective To investigate the MRI features of intracranial solitary fibrous tumors （ISFT） and to improve the MRI diagnosis and differential diagnosis ability compared with pathology. Methods The MRI, clinical and pathological data of 6 cases of ISFT proved by operation and pathology in our hospital from May 2012 to Feb 2017 were retrospectively studied. There were 4 males and 2 females, aged 45 to 73 years, with an average age of 59.67 years. Results The maximum diameter of the 6 cases ranged from 2.5 to 6.3 cm, all of which had the characteristics of intracranial and extracerebral tumors. 1） one case was located in the left frontal region, one case in the right parie-occipital region, one case in the right posterior parietal region, one case spanning the left cerebellar tentorium, one case in the left parietal region near the falx, and one case in the left posterior medulla oblongata; 2） MRI manifestation all the masses were round and round like, with edema around them, irregular shape being partial lobulated. The signal was uneven, mainly with slightly longer / iso-T 1, heterogeneous long T 2 signal intensity, low signal area of T 2WI observed in the lesion. When enhanced scan, the aforementioned T 2WI low signal area was obviously enhanced. One case appeared short T 1 and short T 2 signal intensity. The ＂dural tail sign＂ was seen in two cases, one case presented with intralesional thick and tortuous vessels; 3） pathology showed all the cases were spindle cell tumors under the microscope. Immunohisto chemistry results were as follows： Vim （＋ - ＋ ＋）, CD34＋＋, bcl-2 （＋ - ＋ ＋）/（-）, CD99 （＋ - ＋ ＋）, Ki67＋ （proliferation index 〈 10%）, EMA （-）, S-100 （-）, SMA （-）, GFAP （-）. Conclusion The MRI manifestation of ISFT has some characteristics, which is an inevitable reflection of its pathological basis and is helpful for correct diagnosis before operation.