成人幕上原始神经外胚层肿瘤影像特征及误诊分析  

Supratentorial primitive neutoectodermal tumors in adults imaging findings and analysis on misdiagnosis

作　　者：廖书坤 李晓丹 郭柳姬 马立超[1] 丁洁[2] 许乙凯[1] 吴元魁[1] 

机构地区：[1]南方医科大学南方医院影像中心,广东广州510515 [2]南方医科大学第一临床医学院,广东广州510515

出　　处：《实用放射学杂志》2018年第2期176-179,共4页Journal of Practical Radiology

摘　　要：目的 探讨成人幕上原始神经外胚层肿瘤（sPNET）的CT和MRI表现并分析误诊原因。方法 回顾性分析15例经病理证实的成人sPNET 的CT和MRI表现。13例行MRI平扫及增强扫描，其中4例同时行CT扫描；另2例仅行CT平扫。结果 病灶多位于颞叶、额叶及额颞叶（9/15），体积较大，边界多清楚（12/15），瘤周水肿轻中度为主。肿瘤实性部分以高密度、T1WI等/稍低信号、T2WI等/稍高信号为主，可见钙化（2/6）、坏死/囊变（13/15）、出血（8/15）、流空血管影（11/13）。大部分呈不均匀明显强化（12/13），7例呈不规则环形强化。5例扩散加权成像（DWI）示肿瘤实性部分均为高信号。66.7%术前误诊为胶质瘤（10/15），诊断为室管膜瘤2例，脑膜瘤和生殖细胞肿瘤各1例，另有1例未做出明确诊断。结论 成人sPNET具有特征性的CT和MRI 表现；其发病率超低和影像医师对其影像特征不了解是误诊的主要原因。Objective To investigate the CT and MRI features of supratentorial primitive neuroectodermal tumors （sPNET） in adults,and to analyze the reasons of misdiagnosis.Methods The CT and MRI features of 15 patients with sPNET confirmed by pathology were analyzed retrospective.13 of 15 patients were underwent plain and contrast enhanced MRI,4 patients were also performed CT scan and the other 2 patients were underwent CT plain scan only.Results Nine of 15 lesions were located in the temporal and/or frontal lobe,with clear margin in 12 lesions,and mild to moderate peritumoral was noted in most cases.The solid portion of the lesions were hyperdense on CT, isointense or slightly hypointense on T1WI, and isointense or hyperintense on T2 WI compared to the gray matter. Calcification （2/6）, necrosis or cystic degeneration （ 13/15）, hemorrhage （8/15） and flow void signal （11/13） were seen.Twelve lesions showed significantly heterogeneous enhancement and 7 lesions showed irregular ring-enhancement.The solid parts in 5 lesions showed hyperintensity on diffusion-weighted imaging. Preoperatively, the lesions were misdiagnosed as glioma in 10 cases, ependymoma in 2 cases, meningioma in 1 case and germ cell tumor in 1 case, respectively;and 1 case was not diagnosed definitely.Conclusion Supratentorial PNET in adults has characteristic CT and MRI features,and the main reasons accounting for misdiagnosis are its extraordinary low incidence and that radiologists do no master its imaging features.

关 键 词：原始神经外胚层肿瘤 成人 计算机体层成像 磁共振成像 

分 类 号：R739.4[医药卫生—肿瘤] R814.42[医药卫生—临床医学]