BCL-2 protein expression in a case of AIDS-related PCNSL (DLCL). The microphotograph shows that the tumor consists of large tumor cells with immunoblastic morphology. BCL-2 positivity is manifested as cytoplasmic staining in several tumor cells. Paraffin-embedded tissue section, ABC-px immunostaining and tyramide amplification, hematoxylin counterstain. Original magnification × 250.