A Wilms' Tumor with Spinal Cord Compression: An Extrarenal Origin?

Spinal cord compression in Wilms' tumor (WT) is an extremely rare event that can have a very poor prognosis if not taken care of rapidly. Most cases reported in the literature involve widely metastatic patient with bone or paraspinal metastases or occasionally intradural metastasis. Here, we present the case of a 3-year-old girl of WT confirmed by biopsy, with spinal cord compression due to the direct contiguous spread of a tumor through 2 vertebral foramina. Abdominal ultrasonography and magnetic resonance imaging performed for an abdominal mass revealed a large heterogeneous tumor near the upper pole of the left kidney. A nodular infiltration extended through the T11-L1 and L1-L2 neural foramina, forming an intraspinal mass that compressed the spinal cord. Major paresthesia subsequently occurred, requiring urgent treatment with corticosteroids and chemotherapy. The evolution was rapidly satisfying. After six courses of chemotherapy, a left nephrectomy was performed. Macroscopic examination identified a large tumor attached to the kidney without renal infiltration. Microscopical examination concluded to a nephroblastoma with regressive changes, of intermediate risk. Evolution at 6 months is satisfactory, with no neurological deficit. The histological aspect of the tumor and the clinical outcome suggest that she had an extrarenal WT that spread through the vertebral foramina and was secondarily attached to the kidney.