Pathologic features of HHV-8-associated multicentric Castleman disease, plasmablastic histopathology

(A) In this field, the interfollicular regions are expanded by numerous plasma cells, and sinuses are patent. Small lymphoid follicles are also present. Hematoxylin and eosin stain.
(B) In this field, the boundary between the follicle mantle zone and the interfollicular region is indistinct. Hematoxylin and eosin stain.
(C) In the follicle mantle zones, large, atypical plasmablasts are present. Hematoxylin and eosin stain.
(D) HHV-8+ cells are preferentially identified in the mantle zones. Some of these cells are large, consistent with plasmablasts. Immunohistochemistry with antibody specific for HHV-8 latent nuclear antigen-1 with hematoxylin counterstain.