Computed Tomography Appearance of Inflammatory Myofibroblastic Tumor in the Mediastinum:

Mediastinal Myofibroblastic Inflammatory Tumor Compressing the Airway: An Unusual Cause of Dyspnea in a 12-Year-Old

A healthy 12-year-old presented with wheezing and progressive dyspnea over a 10-month period. He had several general physician consultations and emergency visits during this time and was treated as an asthma exacerbation with no clinical response. He was referred to the pediatric pulmonologist and a tracheal deviation in his previous two chest X-rays was noted, therefore further studies were performed. A severe extrinsic tracheal compression due to a mediastinal mass was documented. He was taken into surgery where a partial resection of the tumor was made. The biopsy of the tumor reported an inflammatory myofibroblastic tumor (IMT), a rare tumor with an atypical presentation, which made this case a diagnostic challenge.

Radiologic and Clinicopathologic Findings of Inflammatory Myofibroblastic Tumor

PURPOSE

The aim of the study was to describe the clinical, radiographic, and pathologic features of inflammatory myofibroblastic tumor (IMT) to enhance the recognition of this rare disease.

MATERIALS AND METHODS

The clinical, imaging, and pathologic findings were retrospectively reviewed in 54 patients with IMT lesions, which were conformed by biopsy or surgical pathology. Of 54 patients, 51 had preoperative computed tomography (CT) examination and 13 had preoperative magnetic resonance imaging records.

RESULTS

The clinical appearances of these 54 patients had some relationship with the locations of lesions. Of 54 IMT patients, 87.0% cases (47/54) had solitary lesion. The mean long diameter of the lesions located at the sites of chest, abdomen, and pelvic regions was bigger than that of other locations (F = 3.025, P = 0.038). On plain CT images, soft tissue mass was found in all IMT lesions, except for 3 lesions that arose in the intestine tract, appearing as focal or diffuse thickening in the bowel wall. After contrast administration, all lesions were persistently enhanced; 72.7% cases (24/33) demonstrated heterogeneous enhancement with various cystic regions. Comparing the CT features with different anatomic lesions, ill-defined margin on the plain CT images and calcification were seen more frequently in the lesions of the head and neck (P = 0.010 and 0.035); however, the other radiological findings had no significant differences (all P > 0.05). Twelve of 51 IMT patients showed invasion into adjacent structures. On magnetic resonance imaging, 92.3% lesions (12/13) showed soft tissue masses demonstrating isointense to hypointense contrast compared with skeletal muscle on T1-weighted images and heterogeneously high signals on T2-weighted images; 85.7%(6/7) of lesions were heterogeneously enhanced with cystic changes. Immunohistochemistry showed that the percentage of positive staining for SMA, vimentin, anaplastic lymphoma kinase, CD68, CD34, CD99, B-cell lymphoma/leukemia-2, cytokeratin, Desmin, and S-100 protein were 88.9%, 87.0%, 44.4%, 59.3%, 53.7%, 29.6%, 42.6%, 28.5%, 13.0%, and 24.1%, respectively.

CONCLUSIONS

Inflammatory myofibroblastic tumor can involve any part of the body, and the clinical and radiological appearances are various owing to different anatomic sites. An ill-defined soft tissue mass heterogeneous enhancement with or without invasion into adjacent structures on computed tomographic or magnetic resonance images and positive staining for SMA and vimentin on immunohistochemical examination could suggest the diagnosis.

Imaging of childhood inflammatory myofibroblastic tumor

BACKGROUND

Inflammatory myofibroblastic tumor is a rare benign neoplasm and most commonly involves the lung but occurs in extrapulmonary locations.

OBJECTIVE

To present imaging findings in inflammatory myofibroblastic tumors in children based on a single-centre experience.

MATERIALS AND METHODS

We retrospectively reviewed CT and MRI findings of children diagnosed with inflammatory myofibroblastic tumor in a single institution.

RESULTS

We identified 15 children (range: 1-17 years) with inflammatory myofibroblastic tumor. The tumor was localized to the lung (n = 5), mediastinum (n = 3), trachea (n = 1), bronchus (n = 1), abdomen (n = 2) and orbit (n = 3). All the extraorbital tumors were solid masses with homogeneous or heterogeneous enhancement. Four lung tumors and one posterior mediastinal tumor contained calcification. Local recurrence following surgical removal occurred in two children with invasion of the esophagus and of the left atrium in one. Localized masses were seen in all children with orbital tumour. Two of these had episcleritis and perineuritis; one had episcleritis, tendonitis, perineuritis, myositis and dacryoadenitis.

CONCLUSION

The locations and imaging features of inflammatory myofibroblastic tumors are variable.

Mesenchymal tumours of the mediastinum--part I

The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.

Successful surgical management of a rare esophageal inflammatory myofibroblastic tumour: a case report

Inflammatory myofibroblastic tumour (IMT) is an uncommon mesenchymal tumour, which can occur anywhere in the body, rarely in esophagus. Mostly, the diagnosis is postoperative, after the hispathological evaluation of the specimen. There are no definite guidelines regarding the diagnosis and management. Here, we report a 60 year old lady presenting with dysphagia, diagnosed to have a submucosal esophageal tumor with Barium esophagogram and contrast enhanced computed tomography. She was managed successfully with surgical enucleation with the final histopathological diagnosis of IMT. Surgical excision is not only therapeutic but also diagnostic in such cases.