Recent Advances in Castleman Disease

Background: Castleman disease (CD) encompasses a spectrum of rare disorders with characteristic histopathological features. Unicentric CD (UCD) is a benign, local hyperplasia of lymphoid tissue that is usually curable. Multicentric CD (MCD) manifests as a potentially life-threatening systemic disease with complex symptomatology which is mostly due to an overproduction of interleukin-6 (IL-6) or dysregulation of IL-6-related signaling pathways. From a therapeutic perspective, it is important to distinguish idiopathic MCD (iMCD) from those cases that are associated with the human herpesvirus-8 (HHV-8 + MCD). Summary: During recent years, it has become increasingly clear that even HHV-8-negative MCD is not a homogeneous entity and that there are clinically distinct variants. International consensus guidelines for diagnosis and treatment have been developed for iMCD and UCD. Key Messages: We herein summarize recent advances in diagnosis, treatment, and novel insights into the pathogenesis of this disease.