Liposclerosing myxofibrous tumor: A radiologic-pathologic-distinct fibro-osseous lesion of bone with a marked predilection for the intertrochanteric region of the femur

PURPOSE: To describe the characteristic features of liposclerosing myxofibrous tumor (LSMFT) of bone. MATERIALS AND METHODS: The radiographs and clinical histories of 39 patients (21 male, 18 female; mean age, 42 years; age range, 15-69 years) with histologically verified LSMFT of bone were retrospectively studied. RESULTS: LSMFT had a predilection for the proximal femur; more than 90% (30 of 33) of the femoral lesions were in the intertrochanteric region. Radiographs showed an indolent growth pattern with a well-defined and often extensively sclerotic margin. The bone contour either was normal or showed mild expansile remodeling. Mineralization within the lesion was not uncommon. Scintigrams showed mild to moderate focal tracer accumulation. Findings at computed tomography reflected those at radiography, whereas magnetic resonance imaging findings were nonspecific. Four (10%) patients had evidence of malignant transformation. CONCLUSION: The radiologic appearance of LSMFT in the intertrochanteric region of the femur is characteristic. The substantial prevalence of malignant transformation associated with LSMFT underscores the need for close observation of this lesion.