Intra-abdominal and retroperitoneal liposarcomas.
Nine primary intra-abdominal or retroperitoneal liposarcomas, of which eight were recurrent tumors, were surgically resected and enrolled in this study. Histopathological examination of primary tumors revealed that the number of well-differentiated, pleomorphic and myxoid type was two, four and three, respectively. In two recurrent cases, histological differentiation changed from well-differentiated type into myxoid or pleomorphic types. Prognoses of patients with large tumors (a 20 cm) were significantly poorer than for patients with small tumors (< 20 cm). Labelling index of Ki-67 of recurrent tumors increased in two cases. The tumor size affected prognoses of patients with intra-abdominal or retroperitoneal liposarcoma. Combined resection was important to get a tumor-free margin.