Management of intravascular thrombus in cases of bilateral Wilms tumor or horseshoe kidney

J Pediatr Surg. 2022 Sep;57(9):166-173. doi: 10.1016/j.jpedsurg.2021.07.025. Epub 2021 Aug 5.


Purpose: To describe the oncologic and surgical management of bilateral Wilms tumor or Wilms tumor arising in a horseshoe kidney with intravenous tumor thrombus to help pediatric surgeons negotiate this rare and difficult anatomic circumstance.

Methods: A single-institution, retrospective medical record review identified 4 cases of bilateral WT and one case of WT arising in a horseshoe kidney with intravenous tumor thrombus between 2009 and 2021. The presentation, imaging, chemotherapy regimen, intraoperative approach, and surgical and oncologic outcomes were reviewed for each of these patients.

Results: All patients received a total of 12 weeks of neoadjuvant chemotherapy. In two patients, a staged approach to the bilateral tumors was undertaken with the first side being operated on after six weeks of therapy and the other side undergoing surgery after an additional six weeks of therapy. Of five patients, four underwent nephron-sparing surgery of all tumors and one underwent unilateral radical nephroureterectomy with contralateral nephron-sparing surgery. Tumor thrombectomy was performed in four of five cases; one patient demonstrated a complete response of the intravenous tumor thrombus to neoadjuvant chemotherapy and did not require thrombectomy. Three patients received adjuvant flank radiotherapy. Three patients developed medically managed stage II or III chronic kidney disease and no patient required renal replacement therapy or kidney transplant to date.

Conclusion: Nephron-sparing surgery is feasible and safe to perform in selected cases of bilateral Wilms tumor with intravascular thrombus by utilizing three-drug neoadjuvant chemotherapy, staged approaches to each kidney when appropriate, and detailed preoperative and/or intraoperative mapping of renal venous anatomy. Successful nephron-sparing surgery with tumor thrombectomy is dependent on a branched renal venous system or the presence of accessory renal veins.

Level of evidence: Level 4.

Keywords: Bilateral Wilms tumor; Horseshoe kidney; Intracaval tumor thrombus; Nephron-sparing surgery; Venous thrombectomy.

MeSH terms

  • Child
  • Fused Kidney* / complications
  • Fused Kidney* / surgery
  • Humans
  • Kidney Neoplasms* / complications
  • Kidney Neoplasms* / surgery
  • Nephrectomy / methods
  • Retrospective Studies
  • Thrombosis* / etiology
  • Thrombosis* / surgery
  • Treatment Outcome
  • Wilms Tumor* / complications
  • Wilms Tumor* / surgery