Abstract: Objective: To investigate the clinical manifestations, diagnosis and treatment of multicentric Castleman's disease. Methods:A retrospective review of 12patients admitted to the First Hospital of China Medical University during the period from October 2001 through May 2009 with the histopathologic diagnosis of Castleman's disease was performed. The clinical course of diagnosis and treatment and the outcome of this uncommon clinicopathologic entity were analyzed. Results: Multicentric Castleman's disease is characterized by polylymphadenopathy and involvement of multiple organs and systems, and it is far more varied in its clinical course than localized disease. The 12-case study group is classified into 3 histopathologic groups: hyaline-vascular, plasma cell, and mixed variant, accounting for 58%,33%, and8% of the patients, respectively. Among the 10multicentric cases with follow-up data available,2 cases achieved complete remission (with the pathologic subtype of hyaline-vascular variant), 5 were alive with disease still present (3 with hyaline-vascular variant and 2 with plasma cell variant), while3 other cases died (2 with plasma cell variant and one with mixed variant). Conclusion : Accurate diagnosis of multicentric Castleman's disease is crucial and is preferably done by histopathological evaluation of an excised specimen. On the other hand, to make a diagnosis at an earlier stage, various sites on typical lymph nodes can be selected and if necessary be repeatedly biopsied. Unlike surgical resection which can cure the localized type, the multicentric type, with poorer prognosis, is treated mainly with systemic therapy. Although new treatment strategies are being explored based on underlying pathophysiology, optimal standard therapies have not yet been established for multicentric Castleman's disease.