恶性外周神经鞘瘤的影像特征与临床分析

Imaging and Clinica Features of Malignant Peripheral Nerve Sheath Tumor

目的探讨恶性外周神经鞘瘤(MPNST)影像与临床特征。方法回顾性分析经病理证实的15例MPNST的临床及影像资料,11例行CT检查(4例平扫、7例平扫及增强扫描),9例MR检查(2例平扫、7例平扫及增强扫描),其中3例同时行CT、MR平扫,2例同时行CT、MR增强扫描。结果男4例,女11例,发病年龄9~76岁。发生于腰背及脊柱5例,头颈部3例,四肢2例,胸壁、腹壁、左髋部、左肺、腹膜后各1例,均为肿块型。临床表现为伴或不伴疼痛的肿块,首诊时5例(33%)伴远处转移,术后3例(20%)转移并1例死亡,7例(47%)于2年内复发。CT平扫10例(91%)呈不均匀等低密度;MR平扫示4例(44%)T1WI抑脂序列呈稍高信号具有特征性,6例(67%)于T2WI抑脂、9例(100%)于扩散加权成像(DWI)序列均呈混杂高信号;CT/MR增强扫描,12例(100%)实性肿块或囊实性肿块实性区呈中度以上不均匀性、渐进性强化,7例(58%)以外周强化为主。结论MPNST临床症状不典型,早期转移、术后复发多见;T1WI抑脂稍高信号,不均匀、渐进性并以外周为主的强化方式有助于诊断。

Objective To explore the imaging and clinical features of malignant peripheral Nerve Sheath Tumor(MPNST).Methods The clinical and imaging data of 15 cases of MPNST confirmed by pathology were retrospectively analyzed.CT examinations were performed on 11 patients(4 plain scan cases,7 plain and enhanced cases).MR examinations were performed on 9 patients(2 plain scan cases,7 plain and enhanced cases).Among the above patients,3 patients underwent plain CT and MR examinations and 2 patients were simultaneously performed with CT and MR enhancement.Results The ages of onset were 7-76 years.The male-to-female ratio was 4 to 11.Five tumors were located in the back and spine,three were located in the head and neck and two were located in the limbs.The thoracic wall,abdominal wall,left hip,left lung and retroperitoneal space was involved in one case each.They were all massive type.The clinical manifestations of MPNST were shown as single mass with mild or lack of pain.Metastases occurred in 5/15(33%)patients during the initial visit in hospital and in 3/15(20%)postoperatively and 1 patient died among the three patients.MPNST recurred in 7/15(47%)within two years.On the plain CT images,10/11(91%)tumors showed heterogeneous and slightly low density.4/9(44%)tumors were slightly higher signal on fs-T1WI and 6/9(67%)tumors were heterogeneous high signal on T2WI.9/9(100%)tumors had heterogeneous high signal intensity on DWI.All solid masses or solid areas of the masses enhanced heterogeneously and progressively,and 7/12(58%)enhanced mostly displayed peripheral enhancement.Conclusion MPNST had atypical clinical manifestations.It metastasized early and commonly recurs.MPNST had slightly higher signal intensity on fs-T1 WI and enhanced heterogeneously,progressively with predominantly peripheral enhancement.These features would help improve the diagnosis,accuracy and prognosis of MPNST.