Histologic features of AR-EBVLPD. (A) Reactive follicular hyperplasia. (B) Reactive paracortical hyperplasia. (C) Plasma cell hyperplasia: monomorphic proliferation of uniform plasma cells. (D) Poly-N: polymorphous infiltrate comprising plasma cells, lymphocytes, and immunoblasts with occasional eosinophils. Occasional atypical HRS-like cells are noted (inset). (E) Poly-E–EBVMCU: well-circumscribed ulcerated lesion in oral mucosa with polymorphous infiltrate and HRS-like cells (inset). (F) DLBCL: “conventional” histologic picture with a diffuse proliferation of large mononuclear cells with centroblastic and immunoblastic features. Occasional pleomorphic cells are noted, but an inflammatory background is absent. (G) DLBCL: large numbers of HRS-like cells are present. (H) Plasmablastic lymphoma: the cells show basophilic cytoplasm and most have prominent nuclei (H&E; original magnifications, ×20 (B,E); ×40 (A); and ×400 (C,D,F-H and insets).