Primitive neuroectodermal tumor with kidney involvement: a case report.

Primitive neuroectodermal tumor (PNET) is usually an aggressive, rapidly progressing and metastasizing tumor. Occurrence of this type of tumor in the kidney is considered as unusual and few cases have been reported so far. We present a metastatic PNET arising probably from the kidney in a 17-year-old female patient with local invasion and metastasis to the stomach. PNET should be considered as a differential diagnosis of a large heterogeneous soft tissue mass in the abdomen, especially in those with widely local invasion and metastases.