Abstract:

Objective: To explore the radiological and clinicopathologic characteristics of liposclerosing myxofibrous tumor (LSMFT). Methods: Ten patients diagnosed with LSMFT were enrolled during May 2015 to 2019 in our hospital, and the data including the manifestations, imaging and pathological characteristics were studied retrospectively, and related literatures were reviewed. Results: There were 7 male and 3 female in 10 cases and the average age of onset was 49 years (22-68). All cases showed non-specific clinical symptoms, in which 7 cases complained local pain in lower limb and swollen joint and 2 cases had walking difficulty, while 3 cases didn't show any symptoms. As consistent with literatures, most lesions (8/10) located in the proximal femur or the intertrochanteric region, and 2 lesions were in the proximal tibia. The CT and X-ray images showed a geographic osteolytic lesion with intramedullary eccentric shape or along femur longitudinal axis. The lesions had clear edges, nonhomogeneous density or sclerotic margin. MRI showed the lesions had relatively homogeneous signal on T1WI, and heterogeneously high signal intensity on T2WI with fat suppression. Microscopically, LSMFT was characterized with diversely histologic pattern. The myxofibrous areas, bone trabeculae similar to fibrous dysplasia (FD) and irregular calcification were found in all cases (10/10), and lipomatous areas, Pagetoid bone, xanthoma cells and cyst formation were showed in 7/10, 6/10, 2/10, 1/10 cases, respectively. All patients were treated with curettage and no recurrence were reported during 1-60 month follow-up. Conclusions: LSMFT is a rare benign fibro-osseous lesion with unique radiological features and multiple pathological structures,characterized with myxofibrous areas, irregular calcification and bone trabecula similar to FD. LSMFT should be distinguished from FD and bone infarction.

Key words: Bone tumor, Liposclerosing myxofibrous tumor, Fibrous dysplasia, Lytic lesion, Pathology