Definition for Castleman's disease

Castleman's disease is a rare disorder characterized by non-cancerous growths (tumors) that may develop in the lymph node tissue throughout the body. more

Castleman's disease is a rare disorder characterized by non-cancerous growths (tumors) that may develop in the lymph node tissue throughout the body. It involves hyperproliferation of certain B cells that often produce cytokines. There are several variants of this disease. About 50% of Multicentric Castleman's disease (MCD) is caused by Kaposi's sarcoma-associated herpesvirus (KSHV), a gammaherpesvirus that is also the cause of Kaposi's sarcoma and primary effusion lymphoma, while the remainder of MCD are of unknown cause. The form of MCD most closely associated with KSHV is the plasmacytic form of Castleman's disease while another pathologic form, the hyaline-vascular form, is generally negative for this virus. In all cases, Castleman's disease is likely due to hypersecretion of the cytokine IL-6. In KSHV positive tumors, this is most likely due to expression of the a virus-encoded cytokine, vIL-6, while KSHV negative tumors appear to be the result of over secretion of human IL-6. The most striking clinical features of MCD are high fevers, anemia, and low white blood cell counts, which appear to be due to the overproduction of interleukin 6. There is no standard therapy for Castleman's disease; MCD has in the past carried a poor prognosis of about 2 years, principally due to autoimmune hemolytic anemia or non-Hodgkin's lymphoma. Recent work with HIV-positive patients with KSHV-related MCD suggests that combined treatment with the antiherpesvirus drug ganciclovir and the antiCD20 B cell monoclonal antibody, rituximab, may markedly improve outcome. less