Treatment of Castleman's disease.

Castleman's disease (CD) was first described in 1954 and further defined in 1956 by Castleman. Since then much has been learned about the heterogeneity of this condition. Subsequently, three pathologic classifications have been developed (hyaline vascular variant, plasma cell variant, and mixed variant) and two clinical classifications (unicentric [unifocal or localized] and multicentric [multifocal or generalized]). The pathology found with the unicentric presentation is most commonly that of the HV variant. It responds well to surgical resection and is associated with a benign course. The multicentric presentation is rarely composed of lymph nodes with HV pathology, but rather with the plasma cell or mixed pathology. This presentation requires systemic therapy and prognosis is guarded. Associated systemic symptoms are common. There is an increased incidence of CD in patients with HIV. The human herpes virus-8 is associated with nearly all of the HIV-associated CD cases and nearly 50% of non-HIV cases. Interleukin (IL)-6 has also been shown to play a significant role in the pathogenesis of the disease. Paraneoplastic and autoimmune entities are not uncommon in the disorder. Variable benefit has been achieved with single agent chemotherapy, combination chemotherapy, interferon (IFN)-alpha, rituximab, anti-IL-6 receptor antibodies, and thalidomide. Patients with CD are at increased risk for developing frank malignant lymphoma.