Wilms Tumor and Other Childhood Kidney Tumors Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Treatment Option Overview
Operative principles have evolved from NWTS trials. The most important role for the surgeon is to ensure complete tumor removal without rupture and perform an assessment of the extent of disease. Radical nephrectomy and lymph node sampling via a transabdominal or thoracoabdominal incision is the procedure of choice. A flank incision should not be performed because of the limited exposure it provides. For patients with resectable tumors, preoperative or intraoperative biopsy should not be performed. Routine exploration of the contralateral kidney is not necessary if technically adequate imaging studies do not suggest a bilateral process. If the initial imaging studies are suggestive of bilateral kidney involvement and depending on the size of the tumor, biopsy or wedge resection may be performed. Alternatively, the contralateral kidney should be explored to rule out bilateral involvement. This should be done prior to nephrectomy since the diagnosis of bilateral disease would dramatically alter the approach.
Partial nephrectomy remains controversial and is not recommended except for children with bilateral tumors, children with a solitary kidney, or rare cases of horseshoe kidney. However, partial nephrectomy has been suggested for Wilms tumor in infants with Denys-Drash or Frasier syndrome in order to delay the need for dialysis.; [Level of evidence: 3iiB] Also, some children who are predisposed to bilateral tumors who have very small tumors detected by ultrasound screening may be considered for partial nephrectomy to preserve renal tissue. In North America, renal-sparing partial nephrectomy of unilateral Wilms tumor following administration of chemotherapy to shrink the tumor mass is considered investigational.[14,15]
Hilar, periaortic, iliac, and celiac lymph node sampling is mandatory even if the nodes appear normal.[10,16] Furthermore, any suspicious node basin should be sampled. Margins of resection, residual tumor, and any suspicious node basins should be marked with titanium clips. Resection of contiguous organs is rarely indicated and there is an increased incidence of complications occurring in more extensive resections involving removal of additional organs beyond the diaphragm and adrenal gland. This has led to the recommendation in current COG protocols that these patients should be considered for initial biopsy, neoadjuvant chemotherapy, and then secondary resection. Pathologically, Wilms tumor rarely invades adjacent organs. Primary resection of liver metastasis is not recommended. Wilms tumor arising in a horseshoe kidney is rare and accurate preoperative diagnosis is important in planning the operative approach. Primary resection is possible in most cases. Inoperable cases can usually be resected after chemotherapy.