Follicular dendritic cells in Hodgkin's disease.

The distribution of follicular dendritic cells (FDCs) was studied in 66 lymph nodes affected by Hodgkin's disease (HD) from as many patients with the use of the monoclonal antibody Ki-FDC1P, which stains FDCs in paraffin sections. Two distinct FDC patterns were distinguishable in the neoplastic areas: pattern A, showing FDC networks occupied by nongerminal center cells, often expanded and disrupted; and pattern B, with FDCs rare or lacking. Pattern A, with follicle-occupying cells represented by epithelioid and lymphocytic and histiocytic (L and H) cells, was found in about 90% of the cases of nodular lymphocyte predominance type and in about half of the cases of nodular sclerosis type, with the follicle-occupying cells being lacunar cells. In the group of mixed cellularity type, approximately one-fifth of the cases exhibited pattern A and in these cases the follicle-occupying cells were Sternberg-Reed, Hodgkin's, and epithelioid cells. The presence of follicular structures, although abnormal, is a more common occurrence in HD than is appreciable with the use of conventional histologic methods.