颅内原发性淋巴瘤的MRI诊断及病理分析

MRI Diagnosis and Pathological Analysis of Primary Intracranial Lymphoma

目的探讨MRI对颅内原发性淋巴瘤的诊断价值及其免疫组化特性,以提高临床诊断的准确性.方法回顾性分析17例颅内原发性淋巴瘤的MRI特征,包括常规平扫、扩散加权成像(DWI)及增强扫描,并结合其中15例的免疫组化特性进行对照分析.结果所有病例病理结果均是非霍奇金弥漫性大B细胞淋巴瘤,其中单发9例(53%),多发8例(47%),肿瘤病灶发生于脑室旁深部白质11例、大脑半球浅部6例、胼胝体2例、小脑1例、脑室内1例.病灶多呈结节状、团块状或环形,T1WI呈等/稍低信号,T2WI呈稍高/等信号,DWI呈高信号,增强检查多呈明显均匀强化,见坏死者5例(29%)及出血1例(6%),7个病灶见"握拳征",4个病灶见"尖角征",4个病灶见"开环征",2个病灶见"蝴蝶征".免疫组化:CD20(+)100%(15/15),CD79a(+)100%(15/15),CD10(+)20%(3/15),Bcl-6(+)53%(8/15),Mum1(+)80%(12/15),Ki-67≥50(+)87%(13/15),GFAP(-)93%(14/15).结论MRI扫描颅内原发性淋巴瘤多呈稍低/等T1WI信号、等/稍高T2WI信号肿块影,DWI呈高信号,增强检查多呈均匀性强化,特征性的MRI表现可以提高诊断的准确性,然确诊仍需依靠病理检查.

Objective To explore the diagnostic value of MRI in primary intracranial lymphoma,compared with pathological features,so as to improve the accuracy of clinical diagnosis.Methods MRI findings of 17 cases were retrospectively analyzed,including conventional plain scan,diffusion-weighted imaging(DWI),and enhanced scan,in combination with 15 cases performed immunohistochemical characteristics.Results The pathological results of all cases were non-Hodgkin diffuse large B-cell lymphoma,including 9 cases single(53%)and 8 cases multiple(47%).11 lesions located in white matter near the ventricles,6 lesions in the superficial part of the brain hemisphere,2 lesions in the corpus callosum,1 lesion in the cerebellum and 1 lesion in the ventricle.Most lesions showed nodular-like or mass-like contrast enhancement on MR imaging,with hypo-or isointense signal on T1WI and iso-or hyper-intense on T2WI.On DWI,all lesions presented hyper-intense signal.5 cases(29%)revealed necrosis,1 case(6%)revealed blood.While 7 lesions showed"fist sign",4 lesions showed"pointed sign",4 lesions showed"incision sign",2 lesions showed"butterfly-like".Immunohistochemical staining showed that CD20(+)was 100%(15/15),as well as CD79a(+)100%(15/15),CD10(+)20%(3/15),Bcl-6(+)53%(8/15),Muml(+)80%(12/15),Ki-67 M 50(+)87%(13/15),GFAP(-)93%(14/15).Conclusion MRI findings of primary intracranial lymphoma can improve the accuracy of diagnosis,but the diagnosis still needs to rely on pathological features.