Immunohistologic features of cases classified as NLRCHD (continued).

(A) Immunostains for IgD revealed that the nodules corresponded to an expansion of IgD⁺ B cells of the mantle zone (polyclonal anti-IgD antibody, peroxidase method with diaminobenzidine development). (B) Labeling for CD21 highlighted the eccentrically placed atrophic germinal centers. (C) CD57⁺ T cells were encountered only within germinal centers. (D) Within the expanded mantle zones, the T cell rosettes surrounding the neoplastic cells were easily identified in CD3 immunostains (using polyclonal anti-CD3 antibody and the APAAP method).