Wilms' tumor involving the inferior vena cava: preoperative evaluation and management.

Neoplastic invasion of the inferior vena cava due to renal tumors (especially Wilms' tumor) is uncommon in children. The tumor thrombus, according to the aggressiveness of the original neoplasm, can extend in diverse ways, obliterate the vascular lumen completely, and even reach the right atrium. The luminal thrombus might be accompanied by the involvement of the caval wall, which requires wide vascular resection. The purpose of this paper is to present our experience with 7 children, aged 18 months and 6 years, affected by caval invasion due to Wilms' tumor. Furthermore, the diagnostic techniques and the surgical treatment in simple caval thrombosis and in associated invasion of the caval wall are described.