RESUMEN
BACKGROUND: Clear cell sarcoma of the kidney (CCSK) in adults is extremely rare. Optimal treatment of adult patients with CCSK remains unclear. CASE PRESENTATION: A 22-year-old man presented with a 2-month history of left flank pain. A color duplex sonography revealed a hypervascular, heterogeneous renal mass. Abdominal and pelvic computerized tomography showed a heterogeneous mass originating from the lower pole of the left kidney and infiltrating to the psoas muscle. Further evaluation including bone scan did not demonstrate any evidence of metastases. A left radical nephrectomy with hilar lymphadenectomy through an intraperitoneal approach with an anterior subcostal incision was performed. The histopathological diagnosis of the mass was a clear cell sarcoma of the kidney. No lymph node metastases were found. Concomitant chemo-radiotherapy was performed. Therapy-related serious side effects were not observed. There was no evidence of local recurrence or metastases during the following twenty-four months after therapy. CONCLUSION: We believe that the combination therapy is efficacious for preventing the local recurrence and distant metastases. Accurate diagnosis is very important and therapy must also include doxorubicin regardless of the disease stage in adult patients with CCSK.