The imaging features of primitive neuroectodermal tumor

MAI Xiaoli; FAN Haijian; YU Hongming; CHANG Ying; SHI Jiong; MU Dan

Abstract：Objective To explore the imaging features of primitive neuroectodermal tumor ( PNET) .Methods The MR/CT imaging of 21 patients with PNET pathologically proved were reviewed retrospectively.The imaging features and pathological char-acteristics were analyzed.Results PNET was more commonly occurred on young people, the median age was 21 years, including 13 males and 8 females.Among 21 patients with PNET, solitary lesion was found in 20 patients, and 1 patient showed multiple lesions which were both located on bone.Sites of lesions involvement were 2 cases in head, 1 case in neck, 2 cases in chest, 1 case in rib, 1 case in axillary, 1 case in abdominal, 1 case in retroperitoneal, 1 case in pelvis, 2 cases in renal, 4 cases in spinal canal, and 5 cases in extremities.All the cases showed soft tissue mass, tumor size ranged from 3.2 cm to 20.0 cm ( average (10.4 ±7.1) cm.The lesions were irregular or spherical, 13 cases with clear circumscribed, 19 cases with inhomogeneous cystic low density/signal intensity within tumors.No obvious calcification or osteoid tissues were found within the lesions.7 cases showed irregular osteolytic lesion and cortical discontinuous in bone, without peristeal reaction or hardened edge.All of the lesions were heterogeneous enhancement on CT/MR.Conclusion PNET can occur in any part of the body.CT/MRI can accurately show the location, size, shape and edge of the tumor, the relationship with surrounding tissue.Certain CT/MR findings may sug-gest the diagnosis of PNET, but still rely on pathological diagnosis.