[Primary leiomyosarcoma of bone: a clinico-pathologic and immunohistochemical study of 3 cases].
Primary leiomyosarcoma of bone is rare. Herein we describe 3 cases with immunohistochemical study. All 3 cases were positive for smooth muscle actin and/or desmin. None was positive for cytokeratin. Differential diagnosis includes metastatic spindle cell carcinoma, other sarcoma (fibrosarcoma, malignant fibrous histiocytoma) and metastatic extra-osseous leiomyosarcoma, mostly from uterus or digestive tract.