title: Cavectomy for the treatment of Wilms tumor with vascular extension.
abstract: OBJECTIVE
  Vascular extension to the vena cava occurs in 4% of Wilms tumor cases and can reach the right atrium in up to 1%. When this happens the thrombus is usually not adherent to the vessel wall, and there is blood flow around it. Preoperative chemotherapy can cause thrombus regression and even resolution. If the thrombus persists after chemotherapy, surgery will be a challenge. On the other hand, if the thrombus invades the vessel wall, its removal may not be feasible. In this situation cavectomy is a good surgical strategy because it provides complete resection. The prerequisite for cavectomy is the absence of blood flow in the vena cava on preoperative Doppler ultrasonography. We report 3 cases of Wilms tumor with vena caval invasion in which cavectomy was performed, and discuss the principles, indications and operative technique.
  
  
  METHODS
  A total of 171 patients with Wilms tumor were treated at our institution between 1984 and 2004. Of these patients 6 with intravascular extension of thrombus within the right atrium were treated with extracorporeal circulation, cardiac arrest and profound hypothermia, and 3 were treated with cavectomy.
  
  
  RESULTS
  There were no instances of surgical complications or postoperative renal failure in our patients who underwent cavectomy. All remain well and free of disease.
  
  
  CONCLUSIONS
  Cavectomy is a safe procedure for treating pediatric patients with Wilms tumor when there is extension and invasion of the vena cava wall without blood flow.
authors.affiliation: Department of Pediatric Surgery, Pediatric Oncology Institute, Federal University of São Paulo, Av. Piassanguaba 2933 ap. 12, São Paulo, 04060-004 Brazil. rodrigocribeiro@uol.com.br
authors.forename: Rodrigo Chaves
authors.initials: RC
authors.lastname: Ribeiro
authors.forename: Sergio Tomaz
authors.initials: ST
authors.lastname: Schettini
authors.forename: Simone de Campos Vieira
authors.initials: Sde C
authors.lastname: Abib
authors.forename: José Honório Palma
authors.initials: JH
authors.lastname: da Fonseca
authors.forename: Mônica
authors.initials: M
authors.lastname: Cypriano
authors.forename: Nasjla Saba
authors.initials: NS
authors.lastname: da Silva
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D009361:Neoplasm Invasiveness; D009392:Nephrectomy; D011859:Radiography; D019043:Vascular Neoplasms / Q000473:pathology / Q000601:surgery*; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000601:surgery*; D009396:Wilms Tumor / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery