Acquired immunodeficiency syndrome-associated T-cell lymphoma: Evidence for human immunodeficiency virus type 1-associated T-cell transformation

The majority of lymphomas in the setting of acquired, iatrogenic, or congenital immunodeficiencies are B-cell lymphoproliferations. We describe a rare T-cell lymphoma in a fulminantly ill patient infected with human immunodeficiency virus type 1 (HIV-1). The T-cell nature of the process was defined genotypically (monoclonal T-cell receptor β-chain [C_Tβ] rearrangement) and phenotypically (CD45RO⁺, CD4⁺, CD5⁺, CD25⁺, CD8^-, CD3^- and negative for a variety of B-cell and monocyte markers). The CD4⁺, CD25⁺ (interleukin-2 receptor [IL-2R]) phenotype with production of IL-2 and IL-2R RNA is analogous to human T-lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia/lymphoma (ATLL); however, no HTLV-1 could be detected. Southern blot analysis did demonstrate monoclonally integrated HIV-1 within the tumor genome. Furthermore, the tumor cells were producing HIV p24 antigen as shown by immunohistochemistry. This is the first case of acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin's lymphoma in which HIV-1 infection may have played a central role in the lymphocyte transformation process.