pediatrics
Wilms Tumor
Diagnosis of Wilms Tumor
Abdominal ultrasonography, CT, or MRI Abdominal ultrasonography with Doppler determines whether the mass is cystic or solid and whether the renal vein or vena cava is involved. Abdominal CT or MRI is needed to determine the extent of the tumor and check for spread to regional lymph nodes, the contralateral kidney, or liver. Chest CT is recommended to detect metastatic pulmonary involvement at initial diagnosis. Diagnosis of Wilms tumor is typically made presumptively based on the results of the imaging studies, so nephrectomy rather than biopsy is done in most patients at the time of diagnosis. Biopsy is not done because of the risk of peritoneal contamination by tumor cells, which would spread the cancer and thus change the stage from a lower to a higher one, requiring more intensive therapy. During surgery, locoregional lymph nodes are sampled for pathologic and surgical staging (see also the National Cancer Institute'sDiagnostic and Staging Evaluation for Wilms Tumor). 