Castleman disease: the great mimic.

Castleman disease is a nonclonal lymphoproliferative disorder and one of the more common causes of nonneoplastic lymphadenopathy. Because of its diverse manifestations and ability to affect any body region, Castleman disease is a great mimic of both benign and malignant abnormalities in the neck, chest, abdomen, and pelvis. Castleman disease most commonly manifests as unicentric disease (unicentric Castleman disease) with a hyperenhancing lymph nodal mass and should be considered in the differential diagnosis of lymphoma, metastatic adenopathy, and infectious and/or inflammatory diseases that result in adenopathy. Castleman disease includes a spectrum of pathologic variants, including the classic hyaline vascular type, the less common plasma cell variant of Castleman disease, and the more recently described multicentric Castleman disease and Castleman disease associated with human herpesvirus 8. Castleman disease has been associated with the human immunodeficiency virus, lymphoma, POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes) syndrome, paraneoplastic pemphigus, and plasma cell dyscrasias. Aggressive forms of Castleman disease with systemic manifestations may occur. Unicentric hyaline vascular Castleman disease is often curable with surgery; however, multicentric Castleman disease may require steroid treatment, chemotherapy, antiviral medication, or the use of antiproliferative regimens because a surgical procedure cannot be curative in this setting. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.316115502/-/DC1.