Castleman disease of the thorax: radiologic features with clinical and histopathologic correlation.

PURPOSE To correlate the radiologic manifestations of thoracic Castleman disease with the clinical and histopathologic features. MATERIALS AND METHODS The clinical, surgical, and histopathologic records; chest radiographs; and computed tomographic (CT) and magnetic resonance (MR) images in 30 pathologically proved cases of thoracic Castleman disease were reviewed. RESULTS Patients with localized Castleman disease (n = 24) typically had the hyaline-vascular type (n = 23), were asymptomatic (n = 14), and had solitary, well-circumscribed mediastinal masses (n = 24). All lesions at contrast material-enhanced CT (n = 13) enhanced. All lesions at MR imaging (n = 5) were heterogeneous and had increased signal intensity on T1- and T2-weighted images. Three patterns were observed on CT or MR images in 20 patients: a solitary, noninvasive mass (n = 10); a dominant infiltrative mass with associated lymphadenopathy (n = 8); or matted lymphadenopathy without a dominant mass (n = 2). Patients with disseminated Castleman disease (n = 6) typically had the plasma cell type (n = 4), were symptomatic at presentation (n = 5), and had bilateral mediastinal masses on chest radiographs (n = 4). At CT, all lesions manifested with diffuse mediastinal lymphadenopathy. All lesions at contrast-enhanced CT (n = 5) enhanced. CONCLUSION Localized Castleman disease manifests as either a solitary, well-circumscribed mediastinal mass or an infiltrative mass with associated lymphadenopathy on CT or MR images. Disseminated Castleman disease manifests with diffuse mediastinal lymphadenopathy.