Management and Outcomes of Wilms Tumor With Suprarenal Intravascular Extension: A Pediatric Surgical Oncology Research Collaborative Study

Abstract

Objective: The purpose of this study was to describe management and outcomes from a contemporary cohort of children with Wilms tumor complicated by inferior vena caval thrombus.

Background: The largest series of these patients was published almost 2 decades ago. Since then, neoadjuvant chemotherapy has been commonly used to manage these patients, and outcomes have not been reported.

Methods: Retrospective review of 19 North American centers between 2009 and 2019. Patient and disease characteristics, management, and outcomes were investigated and analyzed.

Results: Of 124 patients, 81% had favorable histology (FH), and 52% were stage IV. IVC thrombus level was infrahepatic in 53 (43%), intrahepatic in 32 (26%), suprahepatic in 14 (11%), and cardiac in 24 (19%). Neoadjuvant chemotherapy using a 3-drug regimen was administered in 82% and postresection radiation in 90%. Thrombus level regression was 45% overall, with suprahepatic level showing the best response (62%). Cardiopulmonary bypass (CPB) was potentially avoided in 67%. The perioperative complication rate was significantly lower after neoadjuvant chemotherapy [(25%) vs upfront surgery (55%); P =0.005]. CPB was not associated with higher complications [CPB (50%) vs no CPB (27%); P =0.08]. Two-year event-free survival was 93% and overall survival was 96%, higher in FH cases (FH 98% vs unfavorable histology/anaplastic 82%; P =0.73). Neither incomplete resection nor viable thrombus cells affected event-free survival or overall survival.

Conclusions: Multimodal therapy resulted in excellent outcomes, even with advanced-stage disease and cardiac extension. Neoadjuvant chemotherapy decreased the need for CPB to facilitate resection. Complete thrombectomy may not always be necessary.

FIGURE 1

Intravascular Wilms tumor thrombus levels at presentation per Daum staging (Daum). Original artwork.

FIGURE 2

Flowchart comparing outcomes of early and delayed surgery. PSORC indicates Pediatric Surgical Oncology Research Collaborative.

FIGURE 3

The effect of neoadjuvant chemotherapy on thrombus level.

FIGURE 4

A–F, Case of a 3-year-old female who presented with left renal mass and tumor thrombus extending to right atrium with protrusion through tricuspid valve. She was initiated on DD-4A regimen for presumed Wilms tumor. Right atrial tumor thrombus (*) at diagnosis (A) and after 6 weeks of DD-4A (B) with persistent ball-valving protrusion through tricuspid valve (arrows) and negligible regression. C, Left renal mass (*) with occlusive renal vein tumor thrombus extending into inferior vena cava. Left vessiloop encircles vena cava below renal veins; right most vessiloop encircles left renal vein and tumor thrombus. D, After cardiopulmonary bypass, the right atrium was opened, exposing the large tumor thrombus, which is shown being resected (arrow and forceps). E, Atrial tumor thrombus has been completely resected. Arrow shows opened inferior vena cava with tumor thrombus in the distance, which was excised below the level of the hepatic vein confluence. F, The inferior vena cavotomy was repaired primarily and longitudinally (arrow) after excision of all tumor thrombus. The inferior vena cava remained widely patent at 6 months after surgery. Images courtesy of Dr HN Lovvorn 3rd.

FIGURE 5

Overall and event-free survival associated with histology (A), incomplete resection and/or positive margin (B), and tumor thrombus viability (C).