Chest wall tumors: radiologic findings and pathologic correlation: part 1. Benign tumors.

Benign chest wall tumors are uncommon lesions that originate from blood vessels, nerves, bone, cartilage, or fat. Chest radiography is an important technique for evaluation of such tumors, especially those that originate from bone, because it can depict mineralization and thus indicate the diagnosis. Computed tomography (CT) and magnetic resonance (MR) imaging are helpful in further delineating the location and extent of the tumor and in identifying tumor tissues and types. Although the radiologic manifestations of benign and malignant chest wall tumors frequently overlap, differences in characteristic location and appearance occasionally allow a differential diagnosis to be made with confidence. Such features include the presence of mature fat tissue with little or no septation (lipoma), the presence of phleboliths and characteristic vascular enhancement (cavernous hemangioma), evidence of neural origin combined with a targetlike appearance on MR images (neurofibroma), well-defined continuity of cortical and medullary bone with the site of origin (osteochondroma), or fusiform expansion and ground-glass matrix (fibrous dysplasia). Both aneurysmal bone cysts and giant cell tumors typically manifest as expansile osteolytic lesions and occasionally show fluid-fluid levels suggestive of diagnosis.