Primary leiomyosarcoma with the invasion into the intertrabecular space of bone: a case report and the review of the literatures.

Primary leiomyosarcoma of bone is very rare. Most of reported cases were osteolytic. We report a primary leiomyosarcoma arising from the neck of the femur of a 43-year-old woman who had no remarkable abnormalities on plain radiographs. Magnetic resonance imaging (MRI) clearly depicted the lesion. Biopsy revealed it leiomyosarcoma. Gynecological and gastrointestinal examinations ruled out metastatic leiomyosarcoma. Wide excision of the tumor was performed and followed by endoprosthetic replacement of the proximal femur. Microscopic examination revealed tumor cells infiltrating into the intertrabecular space.