Imaging diagnosis of Inflammatory myofibroblastic tumor

Objective:To investigate the CT and MRI features of inflammatory myofibroblastic tumor(IMT)and their value in the clinical diagnosis.Methods:The CT and MRI findings of 20 cases with pathology proven IMT were retrospectively analyzed. of which,13 cases had CT and 5 cases had MRI.Results:The anatomic locations of tumors in these 20 patients included lung(n=8),epiglottis(n=1),nasal cavity(n=1),popliteal fossa(n=1),chest wall(n=2),buttocks(n=1),mandibular molar(n=1),bladder(n=1),superficial soft tissue(n=3).In terms of lung lesions,there were 3 central lesions presented as solid masses with obscure boundary margin;5peripheral lesions as solid masses or nodules with well-defined margin. The lesions out of the lung presented as solid masses or nodules in diverse sites.MRI appearance was mass of a slightly-long T1 slightly-long T2 signal.After contrast enhancement,moderate or marked homogeneous or heterogeneous enhancement were shown in the solid part of tumor,cystic and necrotic without marked enhancement.Tumors were mainly composed of spindle shaped fibrous cells and inflammatory cells on pathology.On immunohistochemistry staining,positive expression of muscle deriving proteins was observed.Conclusion:The final diagnosis of IMT relies on pathology and immunohistochemistry study,CT and MRI examination provides information of accurate anatomic location and are helpful for the clinical diagnosis.