[A case of advanced retroperitoneal dedifferentiated liposarcoma treated effectively with high-dose ifosfamide].

We report a case of retroperitoneal dedifferentiated liposarcoma treated effectively with high-dose ifosfamide. A 59-year-old man received tumorectomy and right nephrectomy for the retroperitoneal liposarcoma. Twenty-two months after the operation, the liver metastasis was resected incompletely. Three months later, right pleural, retroperitoneal and peritoneal metastases appeared. With 6 cycles of high-dose ifosfamide therapy these tumors were reduced partially. Ten cycles of this chemotherapy were administered. These tumors showed regrowth at 14 months after administration of high dose ifosfamide. The combination chemotherapy of ifosfamide and doxorubicine or etoposide was not effective after regrowth of the tumors.