CT features of abdominal inflammatory myofibroblastic tumor

Objective To investigate the CT features of inflammatory myofibroblastic tumor(IMT)and their value in the clinical diagnosis.Methods The CT findings of 12cases with IMT proved by pathological results were analyzed retrospectively.Of these,9cases were performed with plain and contrast medium enhancement,3cases had plain scan only.Results The anatomic locations of tumors in these 12cases included mesenterium(n=6),retroperitoneum(n=2),rectum(n=1),inguen(n=1),greater omentum(n=1),lesser omentum(n=1).8cases were single lesion,4cases were multiple and confertus lesions.9cases had clear border,3cases had unclear margin.7cases were solid-cystic mass,5cases were solid mass.The main CT findings of the 5cases of solid-cystic mass were slight to moderate enhancement in solid part after contrast injection,cystic part without enhancement,4cases of solid mass were heterogeneous enhancement on dynamic CT.The tumors were mainly composed of spindle-shaped fibrous cells,plasma cells and inflammatory cells on pathology,and positive staining for Vimentin(n=12),smooth-muscle actin(SMA)(n=12)and MSA(n=12)were observed immunohistochemically.Conclusion CT imaging can clearly demonstrate the location,size and relationship with the surrounding structures of IMT.The final diagnosis relies on pathology examination.