Primitive neuroectodermal tumor (PNET) is a member of the Ewing’s sarcoma family of tumors
(ESFT). We report a case of PNET in a 66-year-old male who presented with a large
solid tumor within the parenchyma of the middle pole of the left kidney with metastases to
the left adrenal gland and right ischium. A fine-needle biopsy was performed and showed a
small round cell tumor. Results of immunohistochemical staining suggested this tumor belonged
to ESFT. Preoperative VDC-IE (combined vincristine, doxorubicin and cyclophosphamide
followed by another combination of ifosfamide and etoposide) chemotherapy and left
radical nephrectomy and adrenalectomy were performed. The histopathological findings of
the resected tumor were similar to those in the biopsy specimen, but the results of AE1/AE3
were different. For the diagnosis, fluorescence in situ hybridization was performed. Split signals
of the EWSR1 gene were detected, and transmission electron microscopy showed neuroendocrine
granules and microtubules. The final diagnosis of this tumor was PNET of the
kidney