Computed Tomography and Magnetic Resonance Imaging Characteristics of Peripheral Primitive Neuroectodermal Tumor: A Retrospective Analysis of 16 Cases

The aim of this study was to analyze the radiological features of peripheral primitive neuroectodermal tumor (pPNET). The radiological and clinical findings for 16 patients with pPNETs were retrospectively reviewed. The 16 tumors were classified into 4 groups (meninges group, n = 4; spine group, n = 3; bone group, n = 5; soft-tissue group, n = 4), and clinical data, size, and common and unique CT/MRI characteristics were assessed. Peripheral primitive neuroectodermal tumors presented as large solid masses with aggressive extension into the neighboring tissue. Most tumors (11/16) presented with necrosis, and 5 of the 16 cases showed signs of hemorrhage. 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. Peripheral primitive neuroectodermal tumor 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.