CT、MRI检查在外周原始神经外胚层肿瘤诊治中的作用

目的：通过对影像学和病理学的分析，旨在提高对外周神经外胚层肿瘤(pPNET)的认识。方法：回顾性分析有完整影像和病理资料的6例pPNET。结果：软组织pPNET的CT表现为大的、边界不清的软组织肿块，密度不均匀伴坏死囊变，不伴钙化，增强后呈不均匀强化。骨pPNET主要表现为较大的溶骨性骨质破坏伴软组织肿块，无新生骨、瘤骨，增强后不均匀强化。MRI在SE序列T1W表现为等肌肉信号，T2W表现为不均匀高信号，增强后强化不均匀，可见类似包膜和分隔样改变。结论：pPNET的影像学表现没有明显特征性。CT和MRI的作用主要用于描述肿瘤内部结构、侵犯范围以及与周围组织、血管神经的关系，同时可以提供肿瘤远处转移的信息，对临床手术可切除性与评价疗效有着非常重要的意义。

CT and MRI evaluation of peripheral primitive neuroectodermal tumors

Purpose:We present the imaging and pathological features of pPNET tumor in six patients,to add to the knowledge of this tumor. Methods:Retrospective analysis of six pPNETs integrated with data of radiography and pathology. Results:The CT appearance of the tumor arising in soft tissue showed a large,ill-defined,non-calcified mass and heterogeneous appearance with hypodense cystic areas. The tumors demonstrated heterogeneous contrast enhancement. The pPNET arising in bone demonstrated extensive lytic lesion with large soft tissue mass,no newly-born bone and demonstrated heterogeneous contrast enhancement. MRI in SE sequences on T 1 W demonstrated homogeneous intensity for muscle and showed enhancement pattern of multiple internal septa and envelope. On T 2 W image,the tumors were heterogeneous with hyperintense signal. Conclusions:The study of clinic and radiology on pPENT does not show specificity. CT and MRI findings on pPENT can provide more information of it's internal structure,involved area,adjacent vascular and nervous structures. CT and MRI can also be useful in detection of recurrent and metastatic disease and very useful in preoperative staging,and in the planning of the surgical appproach.