CT Appearances of Thoracic and Abdominal Malignant Neurilemoma

Objective To analyse CT appearances of malignant neurilemoma in the thorax and abdomen,in order to improve the diagnostic accuracy of this disorder. Methods There were 9 cases(5 cases in thorax and 4 cases in abdomen) with malignant neurilemoma proved by pathology (7 cases by surgery and 2 cases by CT guided percutaneous puncture biopsy). CT both plain and enhanced scans were performed in all cases. Results Tumors were located in the mediastinum in 5, in abdominal wall and retroperitoneum in 2 respectively .7 cases were isolated masses,2cases were disseminated masses,in company with pleuritic fluid was in 4 and with osteogenic metastasis of vertabral body in one case.The isolated masses appeared as round or ellipse with low density in the centre,the CT value was 5~20 HU,6 cases had complete capsule.The disseminated masses in 2 cases appeared as homogeneous density.On contrast-enhanced scan,the solid parts of masses were enhanced in different degree. Conclusion The isolated thoracic and abdominal malignant neurilemoma is of certain CT characteristics, but the disseminated one is not.