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Purpose: To analyze the radiological features of peripheral primitive neuroectodermal tumor (pPNET). Material and Methods: The radiological and clinical findings of 16 patients with pPNETs were retrospectively reviewed. 12 patients had preoperative MRI examinations and 4 patients had CT examinations. Tumors were defined into 4 groups according to different locations(meninges group,n=4; spine group, n=3; bone group, n=5; soft tissue group, n=4), clinical data, size, margin, CT /MR characteristics were assessed. Result: There were 10 female and 6 male with median age of 20 years old. pPNETs demonstrated large solid masses, with illdefined border and aggressive extension to neighboring tissue. Unenhanced MRI showed 7 cases were isointense and 5 cases were hypointense on T1WI, 6 cases were isointense and 6 were hyperintense on T2WI, unenhanced CT scan showed all cases were hypodense. After the injection of contrast agents, 81.25% of pPNETs (13/16) revealed heterogeneous and significant enhancement. 62.50% of pPNETs (10/16) had ill-defined borders, most tumors in the meninges group (4/4 and soft tissue group (3/4) had necrosis, all cases in meninges group had hemorrhage, no lesion in the 16 cases had calcification. The “dural tail sign” was observed in the meninges and spine groups. The pPNETs of bone demonstrated bony destruction with spiculated periosteal reaction, and small nourishing vessels were found in tumors in the soft-tissue group. Conclusion: pPNET should be suggested as an important differential diagnosis when the tumor presents as a large, ill-defined solid mass with aggressive extension, and significant enhancement.