Castleman disease - one name, many faces

Castleman disease (CD) is a  mesmerising group of disorders mainly affecting lymph nodes sharing some morphological features but with heterogeneous aetiology, clinical presentation and therapeutic approaches. Morphologically, hyaline-vascular (or hypervascular), plasmacytic, and mixed types of changes are distinguished. Confirmation of the diagnosis and subtype of Castleman disease involves meeting or excluding several clinical criteria and therefore requires close cooperation with a clinician. Unicentric Castleman disease involves usually a solitary enlarged lymph node with mild symptoms and excision surgery is often curative. Multicentric forms of Castleman disease affect multiple groups of lymph nodes and are associated with varying degrees of systemic clinical symptoms. Multicentric Castleman disease is either idiopathic or associated with human herpesvirus 8 infection or POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes). Idiopathic multicentric Castleman disease is further divided into a variant associated with TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis / renal dysfunction, and organomegaly), idiopathic plasmacytic lymphadenopathy type, and not otherwise specified variant. The treatment of multicentric forms of Castleman disease is complex and depends on etiological factors, including biological therapy, chemotherapy, or interleukin-6 activity inhibition. The aim of this educational text is to present the current view of Castleman disease and provide a comprehensive description of the morphological changes and clinical characteristics of the individual subtypes of Castleman disease.