Plasmablastic lymphoma in Johannesburg, South Africa, in the era of widescale antiretroviral therapy use.

Objectives: Plasmablastic lymphoma (PBL) is a clinically aggressive lymphoma which has a predilection for extranodal sites and is frequently HIV-associated. The incidence of non-Hodgkin lymphoma is thought to be reduced by widescale antiretroviral therapy (ART) coverage, but the literature is sparse as regards the impact of ART on the incidence of PBL and its outcomes in South Africa (SA). This study aimed to compare factors of interest in cases of PBL diagnosed before and after the widespread availability of ART in Johannesburg, SA.

Methods: All cases of PBL diagnosed in the state sector hospitals of Johannesburg in 2007 and 2017 (before and after the widespread availability of ART, respectively) were extracted from the laboratory information system, and factors of interest compared.

Results: The majority (> 95%) of cases of PBL were seen among people with HIV infection (PWH) at both time-points, and the proportion of patients on ART and with virological suppression (VS) increased significantly in 2017. However, the number of cases of PBL did not differ significantly between the two years assessed, comprising 46/397 (11.6%) and 53/582 (9.6%) of all lymphomas in 2007 and 2017, respectively (P = 0.23). Ongoing risk for PBL among PWH with virological control and immunological recovery was evident in 2017, as 18.9% of the patients had both VS and CD4 counts > 200 cells/μL at diagnosis. Inferior survival times were associated with elevated lactate dehydrogenase (LDH) levels and Epstein Barr virus (EBV) negativity, but were not influenced by the presence of AIDS, ART or VS. EBV negativity was significantly associated with VS, and appeared to flag a particularly aggressive form of the disease.

Conclusions: Widescale ART coverage has not reduced the incidence of PBL in Johannesburg, and an ongoing risk for this disease among PWH with adequate virological control and immunological recovery persists.