Pathology of Castleman Disease.

The term Castleman disease encompasses several distinct lymphoproliferative disorders with different underlying disease pathogenesis, and clinical outcomes. It includes unicentric and multicentric diseases with limited versus significant systemic symptoms, respectively. Importantly, the histopathologic features encountered in the various forms of Castleman disease are diverse, and for the most part, lack specificity, because they are seen to varying degrees in different clinical variants of Castleman disease, and in reactive (autoimmune/infectious) and malignant (lymphoma) contexts. Accordingly, accurate clinical diagnosis of Castleman disease requires careful and thorough clinicopathologic correlation. An overview of the key histopathologic features of Castleman disease is presented.