Primitive neuroectodermal tumor of the kidney: A case report and literature review

Primitive neuroectodermal tumors (PNET) are sarcomas that arise most commonly in the central nervous system. The much less common peripheral PNETs have been reported in many body sites, but renal PNET is extremely rare. Most renal PNETs occur in children or adolescents. We report a 40-year-old man presenting with an enlarging right flank mass for one month. Computed tomography (CT) demonstrated a large exophytic soft tissue mass with heterogeneous enhancement originating from the right kidney and containing areas of necrosis and hemorrhage. The tumor was completely resected, and the pathological examination revealed a renal PNET. The imaging findings of this tumor were discussed, and the literatures were reviewed.