Primitive neuroectodermal tumor of the kidney: a rare case

Background Primitive neuroectodermal tumor commonly occurs in bones and is equivalent to Ewing’s sarcoma. Very few cases have been reported in the literature and they had a very different presentation and very aggressive behavior. Case presentation We present a case of a young 23-year-old male who presented with complaints of pain in left lumbar region of abdomen since 8 months and hematuria off and on. CT scan of the abdomen was done which revealed a large heterogeneously enhancing mass lesion in the left lumbar region arising from the superior and mid-pole of left kidney showing multiple non-enhancing necrotic areas. A diagnosis of left renal cell carcinoma was kept. Through the transperitoneal approach, the left kidney was approached and a left radical nephrectomy was done. The histopathology report revealed the tumor cells to be positive for CD99 and focally positive for Vimentin and negative for cytokeratin thereby making a diagnosis of primary neuroectodermal tumor (PNET). Conclusions Renal PNET is a rare renal malignancy that should be kept in the differential diagnosis of a renal SOL especially when it is a presenting feature in adolescent and young adult. It has a very aggressive course and multimodal therapy has to be considered in its treatment