Follicular Dendritic Cell Sarcoma Arising in Hyaline-Vascular Castleman Disease of Mediastinum: A Case Report

Abstract

Follicular dendritic cell (FDC) sarcoma is a rare neoplasm that is grouped as histiocytic and dendritic cell neoplasm. It can occur primarily in lymph nodes but also in extranodal sites. Follicular dendritic cells are nonlymphoid, nonphagocytic accessory cell in the immune system. Their dendritic cell nature can be demonstrated by the various FDC markers, such as CD21, CD23, CD35, R4/23, and Ki-4p. FDC sarcoma may occur in association with Castleman disease in 10 - 20% cases. We experienced a case of FDC sarcoma associated with hyaline vascular type-Castleman disease (HVCD). A 62-year-old woman presented a posterior mediastinal mass shown by computed tomography. The resected mass was an encapsulated solid mass, measuring 5.5 x 4 cm in size. Microscopically, the tumor was composed of spindle cells showing a fascicular and storiform arrangement. There are some areas reminiscent of HVCD. The tumor cells were positive for the FDC marker CD21. J Med Cases. 2011;2(4):143-146 doi: https://doi.org/10.4021/jmc215w