Molecular genetic and immunohistochemical analyses of a case of multicentric Castleman's disease

Whether Castleman's disease is primarily hyperplastic or neoplastic in nature is a matter of controversy; however, the classical localized form has been thought clinically benign in itself, because it can be cured by local therapy. Recently, a multicentric form of the disease has been reported and has received attention because of its aggressive clinical course and high incidence of developing malignant lymphoma. Here, we describe a case of multicentric Castleman's disease which occurred in a 24-year-old Japanese man. To ascertain whether a monoclonal population was present or not, we performed a molecular genetic analysis of the genes encoding the T-cell receptor and the immunoglobulin, as well as a conventional immunohistochemical analysis. Using these sensitive methods, no monoclonal population could be found. The findings suggest that our case represents a reactive rather than a neoplastic disorder.