Case of 27-year-old male with reportedly well controlled HIV with lymphadenopathy. A biopsy revealed multifocal intravascular large atypical lymphoid cells which expressed CD3, Mum1 and IgM with evidence of EBV and HHV-8/KSHV.

Such cells are typically seen in cases of primary effusion lymphoma, but this patient did not have any effusion. Extracavity involvement by such processes occasional exhibit striking intravascular morphology and may exhibit aberrant T-cell antigens which may lead to an erroneous diagnosis of EBV+ NK T-cell lymphoma if HHV8 IHC and a full complement of plasmacytic markers are not performed.