摘要篇首： Follicular dendritic cell (FDC) is an essential component of the nonlymphoid, nonphagocytic immunoaccessory reticulum cells of the peripheral lymphoid tissue.1 Follicular dendritic cell sarcoma (FDCs) are confined largely to the primary and secondary B-cell follicles, where they form a tight interlacing meshwork. They play a role in the capture and presentation of antigens, generation and regulation of immune complexes. FDCs can be recognized morphologically by their indistinct cellular borders, pale eosinophilic cytoplasm, round-to-ovoid nuclei with delicate nuclear membranes and clear-to-vesicular chromatin with inconspicuous or small nucleoli. FDCs are best identified through immunostaining using CD21, CD35, R4/23, KiM4, KiM4p and Ki-FDC1p.