Clear cell sarcoma of the kidney with inferior vena cava tumor thrombus in a child: A case report

Clear cell carcinoma of the kidney is a rare renal tumor accounting for about 4% of childhood malignant renal neoplasms, and inferior vena cava thrombus is extremely rare. In this report, we present a case of clear cell sarcoma of the kidney with inferior vena cava tumor thrombus in a child, this being the second report of clear cell carcinoma of the kidney with tumor thrombus in Japan. The patient was a 16-month-old girl, who was admitted to our hospital for investigation of a right renal tumor with inferior vena cava thrombus. At first, we performed tumor needle biopsy and made a diagnosis of clear cell sarcoma of the kidney. According to the protocol issued by National Wilms Tumor Study-5, chemotherapy comprising vincristine, doxorubicin, cyclophosphamide and etoposide was started. After 2 cycles of the chemotherapy, radical nephrectomy, thrombectomy and segmental hepatectomy were performed and complete resection was possible. Following radiotherapy to the renal bed and adjuvant chemotherapy with ifosfamide, carboplatin, and etoposide, no clinical evidence of recurrence or metastasis has been noted during the subsequent period of about 1 year.