The renaming of malignant fibrous histiocytoma to undifferentiated pleomorphic sarcoma by the WHO represents an eventual common pathway in tumors progressing to undifferentiated (8). According to the most studies, UPS shows features of both histiocytic and fibroblastic differentiation (7). Predominant spindle cell component with cytologic and nuclear pleomorphism, peripheral histiocyte-like cells with storiform pattern have been observed. Atypical mitosis and necrosis also been observed in many cases (9). In the histopathological feature, five subgroups of this tumor have been identified, including storiform/pleomorphic, myxoid, giant cell, inflammatory and angiomatoid. The giant cell type has more aggressive clinical behavior and poor prognosis. While, the myxoid type is the most common type and its prognosis is better than other types of histology (10). Our case has gain cells type of histology. Maybe, this is one of the reasons for early death and high initial invasion of this tu...