Primary neuroectodermal tumours (PNET) are very aggressive malignant tumours, rapidly progressing to metastasis and death. They rarely involve the kidney, as only 23 cases have been described in the literature. Renal tumours, regardless of their histology, spread to the inferior vena cava (IVC) in 4% to 10% of cases. Invasion of the inferior vena cava wall by tumour thrombus is rare and, when it occurs, is often limited to the ostium of the renal vein. The authors report a case of primary neuroectodermal tumour of the kidney with thrombus in the inferior vena cava ascending to the right atrium (level IV), invading the wall of the IVC and associated with a non-infiltrating papillary urothelial tumour of the ureter. They describe the surgical management of this tumour and present a review of the literature.