Diffuse Large B-Cell Lymphoma in the Public-Sector of Johannesburg, South Africa, in the Era of Widescale Antiretroviral Therapy Use.

Abstract

Diffuse large B-cell lymphoma (DLBCL) is a high-grade non-Hodgkin lymphoma with increased incidence among people living with HIV-infection (PLWH). Although its frequency is reportedly attenuated by antiretroviral therapy (ART), we have previously shown a similar rate of DLBCL in the post-ART era (2017) in Johannesburg, South Africa compared with that observed when ART had only limited availability in the South Africa state-sector (2007). Here, we present a more detailed analysis of DLBCL in the pre-and post-ART eras in Johannesburg. All cases of DLBCL diagnosed in the state-sector hospitals of Johannesburg in 2007 and 2017 were extracted from the laboratory information system, and factors of interest compared. Most (>85%) were observed among PLWH at both time-points; ART-coverage was significantly higher in 2017 compared with 2007, but with failed immunological recovery in 50% of cases. The immunohistochemically-defined cell of origin differed according to HIV-status; the germinal center (GC) and non-GC subtypes predominating in the PLWH and the HIV-negative group, respectively. MYC-gene rearrangement was more common than is reported elsewhere (22.1%), whereas BCL6 and BCL2 gene rearrangements were less so (14.6% and 0%, respectively). Slight improvement in survival was noted in the post-ART era, but remained poor, with bone marrow involvement and albumin levels ≤30 g/L independently associated with mortality. Although the frequency of DLBCL in Johannesburg has not dropped significantly in the post-ART era, a slight improvement in survival is observed. However, outcomes remain poor, indicating a need for further improvements in care.