Primary Ewing sarcoma of the kidney.

Primary Ewing sarcoma (ES) or primitive neuroectodermal tumour (PNET) is a rare tumour in adults and primary renal involvement is extremely rare. Patients with renal ES or PNET respond to and would benefit from conventional ES treatment according to ES study protocols. Here, we report a case of a young woman, presenting with right flank pain and haematuria. After ultrasound and CT evaluation, a right middle pole renal mass was detected. The patient underwent radical right nephrectomy, and a grade 4 ES with peritoneal involvement was documented. Subsequently, the patient underwent adjuvant chemotherapy for 5 months. Follow-up 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT scan demonstrated bilateral cervical, hilar, mediastinal and retroperitoneal FDG-avid adenopathies associated with mild right-sided pleural effusion with no metabolic activity, signifying the role of PET/CT scan in tumour restaging.