8例外周性原始神经外胚层肿瘤的CT、MRI表现并文献复习

摘要

Objective: To analyze CT and MRI findings of peripheral primitive neuroectodermal tumor(pPNET).Methods: The imaging and pathological features of pPNET in 8 cases were retrospectively analyzed.Results: The lesions were located in soft tissue, bone, nasal passages and viscera, and mainly presented as soft tissue masses with infiltrative growth pattern.CT showed inhomogeneous low density and MRI showed inhomogeneous iso-or hypointensity on T1WI and iso-or hyperintensity on T2WI, ill-defined demarcation, necrosis, cystic degeneration, no obvious calcification and heterogeneous enhancement(mild to moderate enhancement for solid components, no significant enhancement for cystic components).pPNET located in bones presented with osteolytic bone destruction and expansile lesion.No obvious tumor bone formation and periosteal reaction were found.Pathological fractures secondary to the tumors occurred.Conclusion: pPNET may present varying imaging features and can only be confirmed by pathological examination and immunohistochemistry.However, CT and MR imaging can clearly show the size of the lesion, internal structure, relationship with adjacent tissues, blood supply, the extent of violations and the distant metastasis, etc., which play key roles in the treatment and prognosis of pPNET.%目的:分析外周性原始神经外胚层肿瘤(pPNET)的CT、MRI表现.方法:结合相关文献,对8例pPNET患者的影像学及病理学资料进行回顾性分析.结果:病灶发生于软组织、骨骼、鼻道、内脏,主要表现为浸润性生长的较大软组织肿块,CT呈不均匀等低密度,MRI呈不均匀等长T1等长T2信号,境界不清,易坏死、囊变,无明显钙化,增强强化不均匀,实性成分轻中度强化,囊性成分无明显强化;位于骨骼的pPNET还表现为溶骨性骨质破坏,呈膨胀性改变,无明显肿瘤骨形成及骨膜反应,可继发病理性骨折.结论:pPNET影像学无明显特异征象,需经病理及免疫组化确诊,但影像学检查能清晰地显示病灶的大小、内部结构、毗邻关系、血供情况、侵犯范围及有无远处转移等情况,对治疗及预后具有重要价值.