Review of siltuximab in the treatment of multicentric Castleman's disease.

Castleman's disease (CD) is a rare lymphoproliferative disorder that has multiple histologic patterns, as well as two distinct clinical forms: unicentric or multicentric. Multicentric Castleman's disease (MCD) may have mild symptoms in some cases, but in others it can progress to severe pancytopenia, life-threatening infection, secondary malignancy, multiorgan failure, or death. Recent research has determined that the etiology of the disease signs and symptoms is related to elevated cytokines, including interleukin 6 (IL-6). Siltuximab is a monoclonal antibody that targets IL-6 and is currently the only US Food and Drug Administration approved therapy for idiopathic MCD. Clinical data have demonstrated significant efficacy and tolerance of siltuximab in patients with idiopathic CD.