Long term survival in a case of concurrent retroperitoneal liposarcoma and renal cell carcinoma: a case report

BACKGROUND: Liposarcoma is one of the most common soft tissue sarcomas found in adults. It has a predilection for retroperitoneal space. Renal cell carcinoma is the most common tumor of the kidney. CASE PRESENTATION: Concurrent retroperitoneal liposarcoma and renal cell carcinoma were found in a 34-year-old Japanese man. The renal tumor was first detected by ultrasonography, it was confirmed by computed tomography, which also identified a presumptive retroperitoneal liposarcoma, and the tumors were further assessed with magnetic resonance imaging. The patient was treated by surgical resection of retroperitoneal liposarcoma and left nephrectomy and has been disease-free for 10 years. CONCLUSIONS: The concomitant occurrence of a renal tumor and a primary primary liposarcoma is rare. The major factors promoting a good prognosis in this case were the favorable histology and the small size of the tumors.