Imaging findings of inflammatory myofibroblastic tumor from the greater omentum

RATIONALE Inflammatory myofibroblastic tumors (IMTs) are rare neoplastic lesions with benign tendency. Even more rare are IMTs from the greater omentum (GO-IMT). A GO-IMT is easily misdiagnosed as other malignant tumors before operation; thus, clinicians need to be familiar with its imaging findings. Here, we report the imaging findings of a GO-IMT patient presenting with a pelvic mass. PATIENT CONCERNS Ultrasound of the IMT in the pelvic cavity showed a hypoechoic mass. A computed tomography (CT) scan showed a nearly circular soft tissue mass with a clear border and heterogeneous density, and the surrounding tissues were pushed and compressed. Contrast-enhanced CT showed severe persistent enhancement in the lesion edges and mural nodules, but not in the central necrosis. DIAGNOSES Histopathology and immunohistochemistry confirmed that the mass was a GO-IMT. INTERVENTIONS The tumor was resected after preoperative preparation. OUTCOMES No recurrence or metastasis was found during a short-term follow-up. LESSONS The GO-IMT is an inferior epigastric mass in the periphery of the bowel, and is usually well-demarcated without calcification or lymphadenopathy. Contrast-enhanced CT showed a heterogeneous hypervascular mass where the center necrosis, the edge of the tumor, and the mural nodules can be partially reinforced.