Human herpesvirus type 8 (HHV8) is a gamma herpesvirus known for its role in lymphoid neoplasms, especially in immunosuppressed patients. We describe the case of a 64-year-old male, without known immunodeficiency, with 1-year-long clinical history of mediastinal and abdominal lymphadenopathies and recurrent pulmonary infections. Histopathological evaluation of a mediastinal lymph node revealed the presence of scattered atypical large cells with Hodgkin and Reed-Sternberg morphology in a background of lymphocytes and extensive areas of fibrosis. The large cells were positive for HHV8 and Epstein-Barr virus (EBV), with a clonal pattern of IGH gene rearrangement. A descriptive diagnosis of "HHV8-positive, EBV-positive Hodgkin lymphoma-like large B-cell lymphoma" was rendered. Interestingly, the retrospective evaluation of a previous biopsy, diagnosed as reactive lymphadenitis, revealed the presence of HHV8- and EBV-positive cells, with a polyclonal pattern and a small peak corresponding to that of the most recent biopsy. This case presents diagnostic challenges due to the presence of particular features not clearly related to current HHV8-associated entities, and also suggests the possibility for disease progression in the spectrum of HHV8- and EBV-associated lymphoproliferative disorders.
Keywords: EBV; HHV8; Hodgkin lymphoma; Immune escape; Large B-cell lymphoma; PD-L1; PD1.