Computed tomography appearance of inflammatory myofibroblastic tumor in the abdomen: CT features and pathologic correlation

Objective: To evaluate CT findings of abdominal inflammatory myofibroblastic tumor (IMT) and the relationship with morphological character. Materials and Methods: CT examinations and pathological findings of ten intra-abdominal IMTs were retrospectively analyzed. The histopathological characteristics of the IMTs were confirmed by two pathologists and two radiologists evaluated CT findings of the lesion, with emphasis on the imaging features compared with the corresponding histopathology. Results: The most common imaging characteristics were presence of heterogeneity, all tumors showed varying degrees of contrast enhancement. Two major different CT patterns were individualized. In type one, the tumor had a distinct boundary without a lobular appearance and displayed hypo-enhanced enhancement after administration of contrast in correlated with the mainly histopathologic findings of spindle cells myxoid and hypocellular fibrous (6/10; 60%). In type two, the lesions exhibited indistinct boundaries or complete capsule, ill-defined growth patterns or low intralesional attenuation with marked heterogeneous or circumferential enhancement, which correlated well with the presence of abundance of micromodule and inflammatory cell infiltration (4/10; 40%). Conclusions: Two major different contrast enhancement CT patterns were individualized can help to determine the relationships with histopathologic findings, while cannot be reliably differentiated from other solid lesions based solely on the CT appearance, combined with diagnostic biopsy may facilitate to achieve a correct diagnosis and treatment.