Fig. 1.

Ki-67 immunohistochemical staining of two representative cases of retroperitoneal liposarcoma. Case 1 was diagnosed with liposarcoma with a Ki-67 labeling index of 50 %. He experienced local recurrence and lung metastasis 19 months after surgical resection and died 18 months after surgical resection. Case 2 was diagnosed with liposarcoma with a Ki-67 labeling index of 2 %. He was alive without any evidence of disease recurrence at the last visit, 108 months after the surgical resection