Aggressive Primary Neuro Ectodermal Tumour in Kidney:A Rare Entity

Primitive Neuro-Ectodermal tumor (PNET) of kidney is a rare tumor with only a few published reports. We report here a case of PNET of kidney in a female aged 20 years who reported of vague pain and lump in loin with a history of rapid increase in size of the lump. On CT imaging, on the left side a large heterogeneous, enhancing mass 15.1x15.4cmx17cm was seen arising from the upper pole of the left kidney. Radical nephrectomy was done along with removal of para-aortic nodes detected intra-operatively. Histopathology revealed sheets of small round cells intervened by hemorrhagic cystic areas with surrounding thin rim of normal kidney tissue. Immunohistochemistry showed diffuse membrane positivity of tumor cells for CD99. Post-operative USG carried out 18 weeks after surgery revealed an ill-defined retroperitoneal mass with ascites, pulmonary metastasis and pleural effusion with presentation of sub-acute intestinal obstruction. The patient succumbed to pulmonary complications later. PNET of the kidney is a very rare and aggressive tumour with poor prognosis. The disease-free survival rate at 7.5 years is around 45-55% in well-confined cases.