Intravascular Extension of Wilms Tumor

Abstract

ObjectiveTo define the incidence and manifestations of and optimal therapy for children with intravascular extension of Wilms tumor. MethodsChildren on a collaborative study of Wilms tumor who had intravascular extension into the inferior vena cava (IVC) or atrium were identified. Surgical checklists and surgical and pathology reports were reviewed. ResultsOne hundred sixty-five of 2,731 patients had intravascular extension of Wilms tumor. The level of extension was IVC in 134 and atrium in 31. Sixty-nine had received preoperative therapy (55 with IVC extension and 14 with atrial extension) for a median of 8 weeks. Complications during preoperative chemotherapy were seen in five patients (tumor embolism and tumor progression in one each, and three with adult respiratory distress syndrome, one of which was fatal). The intravascular extension of the tumor regressed in 39 of 49 children with comparable pre-and posttherapy radiographic studies, including 7 of 12 in whom the tumor regressed from an atrial location, thus obviating the need for cardiopulmonary bypass. Surgical complications occurred in 36.7% of the children in the atrial group and 17.2% in the IVC group. The frequency of surgical complications was 26% in the primary resection group versus 13.2% in children with preoperative therapy. When all the complications of therapy were considered, including those that occurred during the interval of preoperative chemotherapy (one of the five also had a surgical complication), the incidence of complications among those receiving preoperative therapy was not statistically different from the incidence among those who underwent primary resection. The difference in 3-year relapse-free survival (76.9% for 165 patients with intravascular extension, 80.3% for 1,622 patients with no extension) was not statistically significant whether or not it was adjusted for stage and histology.

Nonresponsiveness to Chemotherapy: A Formidable Surgical Challenge in Wilms’ Tumor with Intracardiac Extension

“…Surgical complications in patients with intravascular tumor extension treated with initial surgery were as high as 43 % in NWTS-3, which decreased to 26 % in NWTS-4 [2,8]. These include massive hemorrhage which was the most common followed by tumor embolisation with acute cardiac decompensation or arrest.…”

“…This recommendation was based on the observation that most patients experience shrinkage of the tumor thrombus in response to chemotherapy. In some cases, shrinkage can avoid cardiopulmonary bypass (CPB) [2,8].…”

“…Neoadjuvant chemotherapy lowered the complication rate to 13.2 %. (P=0.053) [2,5,8]. In the UKW3 trial, preoperative chemotherapy was used in 52 of 59 patients with intracaval extension.…”

“…Significant shrinkage of the thrombus and tumor was demonstrated in the majority and avoided the need for cavotomy at the time of delayed nephrectomy in nearly 50 % of patients. However, this approach also has risks which include complications before surgery including pulmonary embolism, tumor progression, febrile neutropenia, acute respiratory distress syndrome, which may be fatal [2,5,8].…”

“…Thus, which approach is best should be determined on an individual basis [2,8]. According to Nini Khozeimeh et al, in these patient with risk for pulmonary embolus, initial surgical therapy is recommended [2].…”