Renal Primitive Neuroectodermal Tumor

Renal primitive neuroectodermal tumor ( PNET) is a rare entity and highly malignant neoplasm. It generally occurs in young adults and children. We report a case of 19-year-old female with the complaint of left flank pain. Ultrasonography showed a tumor of the left kidney. A big left inhomogeneous renal mass of 10x8 cm with areas of necrosis was observed on computed tomography. The patient underwent radical nephrectomy with lymphadenectomy. Immunohistochemical stains were positive for CD99 and FL-1. Immunohistochemical and microscopic results were compatible with PNET. Furthermore, the patient received eight cycles of chemotherapy, and was still alive without metastases at 6-month followup. Renal PNET is a rare and poor prognosis tumor. It is sometimes difficult to discriminate between PNET and Ewing's sarcoma. Renal PNET must be included in the differential diagnosis of renal tumors particularly in young adults and children. With this case report it aimed to create awareness about PNET.