© Cambridge University Press 2014. Introduction Castleman's disease was first described in a case report by Dr. Benjamin Castleman and Towne in 1954. Following this initial description, a case series of mediastinal lymph node hyperplasia which was subsequently coined as Castleman's disease was published. Castleman's disease is a non-clonal lymphoproliferative disorder characterized by angiofollicular lymph node hyperplasia, widespread lymphadenopathy and marked constitutional symptoms in affected patients. Castleman's disease is frequently associated with both human immunodeficiency virus (HIV) and human herpes virus 8 (HHV8) infections. Castleman's disease not infrequently presents with either polyneuropathy, organomegaly, endocrinopathy, M protein and skin changes (POEMS syndrome), Hodgkin's disease, non-Hodgkin's lymphoma, or Kaposi's sarcoma. Clinical presentation can be more localized, with absence of systemic symptoms termed as unicentric presentation. Patients with multi-centric Castleman's disease present with constitutional symptoms and multiple lymph node areas or organs are involved. Although unicentric presentation is frequent and curable in most patients with surgical resection and/or radiotherapy, management of Multicentric Castleman's disease is challenging. There are two main histological subtypes described in Castleman's disease: hyaline vascular subtype and plasma cell variant. Occasionally mixed patterns can occur. In HIV positive patients, lymph nodes are ubiquitously positive for HHV8 infection. There is significant clinical heterogeneity, and the factors guiding therapy are clinical features, HIV status, performance status, localized or multi-centric presentation and in some cases the type of hematological neoplasm associated with. Castleman's disease is a rare condition and no official incidence or prevalence figures are available. The National Cancer Institute in the USA has assigned an orphan status to Castleman's disease.