The MRI findings of meningeal peripheral-type primitive neuroectodermal tumors / 中华放射学杂志

ABSTRACT

Objective To analyze the MRI features of Ewing sarcoma/peripheral primitive neuroectodermal tumors(pPNETs) arising from the meninges.Methods The MRI imaging of 9 patients with Ewing sarcoma/pPNET were reviewed retrospectively,and imaging features and pathological characteristics were analyzed.Results The age of most patients ranged from 10 to 20 years.Magnetic resonance revealed a spindle-like lesion with a wide base in 8 cases.The lesions showed heterogenous iso-or hypo-intense signal on T1 WI in 7 cases,heterogenous hypo-iso-intense signal on T1 WI in 2 case,and iso-or mildly hypderisointense on T2WI in all cases.The solid part of the tumor was heterogeneously enhanced after injection of gadolinium with cyst degeneration or necrosis.The dural tail sign could be seen in 3 cases.The adjacent skull erosion could be seen in 6 cases.The breakthrough of the plate of cranium and soft-tissue invasion was present in 2 cases.The right eye proptosis was present in 1 case.The distant metastasis was found in 3 cases.Pathology showed that the lesions had high cell density.Hemorrhage and necrosis could be observed.The cells were like lymphocytes and spindle cells with transparent cytoplasm.CD99 and Vimentin were expressed in all tumor cells.Conclusion The imaging findings of the meningeal pPNET are different from meningiomas,which could be useful for the diagnosis and differential diagnosis.