Retroperitoneal Unicentric Castleman’s Disease

Abstract

Dear Editor, Castleman’s disease (CD) is an unusual lymphoproliferative disorder first described in 1954 by Benjamin and Virginia.[1] The etiology of the disease is not clear, however, the role of chronic inflammation, immunosuppression, disruption in the production of interleukin 6, and human herpesvirus 8 has been demonstrated. Histologically, there are four subtypes; hyaline vascular, plasma cell variant, multicentric (mixed), and plasmablastic variant.[2] Hyaline vascular CD is characterized by prominent vascular proliferation and hyalinization of the vessel walls. Lymphoid follicles have atretic germinal centers traversed by penetrating vessels that are called “lollipop follicle.” Thickened mantle zones consisting of lymphocytes arranged in layers-onion skin appearance are present throughout the lymph node. Fused mantle zones that contain more than one germinal center can be observed. Extensive vascular proliferation with perivascular hyalinization is evident in the interfollicular areas.[3,4] There are two subtypes clinically, unicentric CD (UCD) and multicentric CD (MCD). UCD typically presents as singular enlarged of lymph node. About 70% of all CD patients are in this group. UCD is often found in both males and females aged 20-30 years and presents asymptomatically.[ 5] MCD is a widespread disease associated with systemic symptoms.[6] Patients of the UCD usually have a good prognosis and are treated with surgical excision.[6] MCD tends to behave aggressively, similarly to lymphoma, and is treated with immunotherapy, chemotherapy, and radiotherapy.[7-9] CD most commonly develops in the mediastinum and the second most common localization cervical region. Retroperitoneal localization is extremely rare.[10]