[A Case of Dedifferentiated Liposarcoma with Reducing Surgery Followed by Chemotherapy and Additional Reducing Surgery].

Dedifferentiated liposarcoma shows poor prognosis because of poor resectability due to aggressive invasion of adjacent organs with multicentric growth and its low sensitivity to chemotherapy. We report herein a case of a giant dedifferentiated liposarcoma, successfully treated by pancreaticoduodenectomy(PD)for tumor reduction and chemotherapy for 1 year after surgery, followed by additional surgery for tumor reduction. The patient is a woman in 50s. CT showed an 18.5×9 cm main mass surrounding the superior mesenteric artery(SMA and SMV)with multiple tumors in the pelvis. Needle biopsy revealed dedifferentiated liposarcoma. Although complete resection or chemotherapy was not feasible, surgery was performed for local control and introduction of chemotherapy. The main tumor was resected by PD with SMV resection and right colectomy. Chemotherapy with doxorubicin followed by eribulin was administered after surgery. The residual lesions were controlled for 1 year. Partial resection of the tumors in the mesentery was performed. Eribulin were administered starting postoperatively. One year and 10 months after the initial surgery, there was no progress in residual disease. Although R2 resection for dedifferentiated liposarcoma shows extremely poor prognosis. Even when complete resection would be difficult, multidisciplinary treatment including debulking surgery might be effective for disease control.