Multi-slice spiral CT imaging of inflammatory myofibroblastoma

Objective: To investigate the multi-slice spiral CT imaging of inflammatory myofibroblastoma (IMT). Methods: Eighteen patients of IMT proved by pathology from March 2005 to February 2008 were examined with multi-slice spiral CT before surgery, in which 14 patients with contrast medium enhancement, and the CT imaging were analyzed retrospectively. The anatomic locations included lung (n=6), liver (n=1), spleen (n=2), commonbile duck (n=1), retroperitoneum (n=11), pelvic cavity (n=1), maxillary sinus (n=2) and superficial soft tissue (n=4). Results: In terms of lung lesions, there were 2 central lesions presented as solid masses with well-defined margin; 4 peripheral lesions, 3 of which lesions presented as irregular solid masses with ill-defined margin and 1 lesion as an round nodule with well-defined margin. The lesions out of the lung presented as solid masses or nodules on CT in diverse sites. After contrast administration, moderate or marked enhancement, homogeneously or heterogeneously, were found. The tumors were mainly composed of spindle shaped fibrous cells and inflammatory cells on pathology, and positive staining for muscle deriving proteins was observed immunohistochemically. Conclusion: MSCT provides accurate anatomic location and helpful information for the clinical diagnosis of IMT, yet the definite diagnosis relies on pathological and immunohistochemical study.