Fibrosarcoma (FSA) of bone is a rare malignant spindle cell tumor exhibiting a fibroblastic differentiation, consisting of relatively monomorphic fibroblastic cells with variable amount of collagen production but no osteoid or cartilage production. It may occur as a primary, de novo, lesion and secondarily after irradiation or by malignant transformation from variable preexisting benign conditions such as fibrous dysplasia, giant cell tumor, Paget disease, bone infarction, diaphyseal medullary stenosis, or chronic osteomyelitis [1, 2]. A majority case of FSA is a solitary lesion, but few cases of multifocal FSA have been also sporadically reported [3–6]. Only 3 out of 286 cases (1%) were multifocal skeletal disease at presentation in Mayo Clinic series [2].