Radiological evaluation of peripheral primitive neuroectodermal tumor arising in abdomen-pelvis region

Abstract

To analyze the CT and MRI features of peripheral primitive neuroectodermal tumor (pPNET) arising in abdomen-pelvis region, and to improve the radiological diagnostic ability of this tumor. The CT and MRI appearances of thirteen abdomen-pelvis region pPNET patients proved pathologically were reviewed retrospectively. The age of diagnosis ranged from 2 years to 72 years (median, 30 years). The tumors were located in the abdomen and pelvic cavity (nine patients), retroperitoneal tissues (two patients), right kidney (one patient) and liver (one patient). The radiological appearances of the tumors resembled heterogeneous soft tissue masses, eight masses with cystic or necrotic areas. Masses in abdomen and pelvic cavity and kidney were well-defined; while masses in retroperitoneal tissue and liver were ill-defined. Heterogeneous enhancement with intravenous contrast agents was evident. There are speckled, patching and irregular calcifications in four patients, one of them with calcification after treatment. Five patients died, and eight patients remiss on clinical follow-up. The radiological features of peripheral PNET are non-specific. CT and MRI are useful in delineating the extent, finding distant metastasis, predicting respectability and monitoring treatment.