Fig. 2

Histology and immunohistochemisty of plasmablastic lymphoma. a Haematoxylin and eosin section shows monotonous, lymphoid cells with “starry sky” pattern (magnification ×100). b Giemsa staining highlights the plasmablastic appearance with eccentrically positioned nuclei, prominent nucleoli and abundant basophilic cytoplasm (magnification ×400). c-f Atypical lymphoid cells were negative for CD20 (c) and CD30 (e), while they were positive for CD79a (d) and CD138 (f) (immunoperoxidase stain; c, d and e magnification × 400; f magnification ×200). g Nuclear proliferation rate, assessed by Ki-67 was approximately 80% (immunoperoxidase stain; magnification × 200). h EBV encoded RNA (EBER) was negative in the nuclei of the atypical cells (magnification ×400)