Malignancies, Particularly B-Cell Lymphomas, Are a Frequent Cause of Mortality in Human Immunodeficiency Virus-1 Patients Despite Highly Active Antiretroviral Therapy

Factors associated with survival in patients with lymphoma and HIV

OBJECTIVE

To analyze the factors associated with survival in the largest cohort of individuals with HIV and lymphoma so far described in Brazil.

DESIGN

A retrospective, observational, multicenter study involving five institutions in São Paulo, Brazil.

METHODS

The medical records of consecutive patients with HIV diagnosed with lymphoma between January 2000 and December 2019 were screened. Inclusion criteria consisted of age over 17 years and a biopsy-confirmed diagnosis of lymphoma. The data collected included age, sex, staging (Ann Arbor system), duration of HIV infection, CD4 + lymphocyte count, HIV viral load, lactate dehydrogenase, erythrocyte sedimentation rate and serum beta-2-microglobulin levels, treatment and outcome.

RESULTS

Overall, 276 patients were included. Median age was 42 years. Most patients were male (74.3%) and with an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 (28.6% and 46.4%, respectively). Most had non-Hodgkin lymphomas (89.2%, n  = 246), particularly diffuse large B-cell lymphoma (40.9%) and Burkitt lymphoma (26.4%). Hodgkin lymphoma accounted for 9.4%. Advanced stages III/IV were predominant (86.8%). HIV viral load at the moment of lymphoma diagnosis was detectable in 52.9% of patients. A CD4 + cell count of <200 cells/μl was recorded for 53% of the patients. Most patients (62.4%) were on combination antiretroviral therapy. The factors that significantly affected survival were: the ECOG performance status, lymphoma subtype, staging, beta-2-microglobulin level, central nervous system (CNS) infiltration, site of CNS infiltration, relapsed/refractory lymphoma and International Prognostic Index score.

CONCLUSIONS

HIV status, CD4 + -lymphocyte count and relapsed/refractory disease affected survival. Rituximab did not appear to improve outcome in HIV-related lymphomas.

Diffuse Large B-Cell Lymphoma in the HIV Setting

Despite the widespread use of combined antiretroviral therapy (cART) and the subsequent decrease in AIDS-defining cancers, HIV-related lymphomas remain a leading cause of morbidity and mortality in people with HIV (PWH). Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma (NHL) subtype in PWH. This lymphoma is a heterogeneous disease including morphological variants and molecular subtypes according to the cell of origin or the mutation profile. In the pre-cART era, treatment with standard-dose chemotherapy induced high rates of toxicity and outcomes were very poor. The introduction of cART and the incorporation of infection prophylaxis allowed the use of conventional intensive chemotherapy regimens used in the general population, such as R-CHOP or R-EPOCH. The use of cART during chemotherapy treatment was initially controversial due to the potential risk of adverse drug-drug interactions. However, the availability of current cART regimens with less potential to cause drug interactions and evidence that cART improves survival rates in NHL strongly support the use of cART in PWH with DLBCL. Consequently, interdisciplinary collaboration between HIV specialists and hemato-oncologists for the management of potential interactions and overlapping toxicities between antiretroviral and antineoplastic drugs is crucial for the optimal treatment of PWH with NHL.

The role of viruses in HIV-associated lymphomas

Lymphomas are among the most common cancers in people with HIV (PWH). The lymphoma subtypes and pathogenesis of lymphoma in PWH are different from the immunocompetent population. It is well-known that HIV causes severe CD4+ T cell lymphopenia in the absence of antiretroviral therapy (ART); however, the risk of developing certain subtypes of lymphoma remains elevated even in people receiving ART with preserved CD4+ T cells. HIV contributes to lymphomagenesis and causes decreased immune surveillance via T cell depletion and dysregulation, B cell dysregulation, and the potential contribution of HIV-encoded proteins. The oncogenic gammaherpesviruses, Epstein-Barr virus (EBV) and Kaposi sarcoma herpesvirus (KSHV, also known as human herpesvirus 8), are the causative agents in the majority of HIV-associated lymphomas. HIV-associated T cell depletion and dysregulation allows EBV and KSHV to proliferate in infected B cells. Specific EBV- and KSHV-encoded proteins participate in B cell activation, and proliferation leading to B cell transformation. Understanding the distinct pathogenesis of HIV-associated lymphomas affords opportunities to develop therapies that specifically target these unique aspects and improve lymphoma outcomes in PWH. Agents being studied that target the specific roles of HIV, EBV, and KSHV in lymphomagenesis include immunotherapies, targeted agents, and cellular therapies.

Epidemiology of haematological malignancies in people living with HIV

People living with HIV or AIDS are at increased risk of Hodgkin and non-Hodgkin lymphoma compared with HIV-negative individuals. Data on the risk of multiple myeloma or leukaemia are inconsistent and of low quality but the risk does not seem to be increased. Specific haematological malignancies occur in different contexts of age, CD4 cell count, HIV control, viral co-infections, or chronic inflammation, and the expansion of combination antiretroviral therapy has led to varied demographic and epidemiological shifts among people with HIV. Increased use of combination antiretroviral therapy has substantially reduced the risks of diffuse large B-cell lymphoma, Burkitt lymphoma, and primary CNS lymphoma, and to a lesser extent, Hodgkin lymphoma. There is no effect of combination antiretroviral therapy use on multiple myeloma or leukaemia. Although many cases of HIV are in low-income and middle-income countries, high-quality epidemiological data for haematological malignancies from these regions are scarce. Closing this gap is an essential first step in decreasing mortality from HIV-associated haematological malignancies worldwide. Finally, although multicentric Castleman disease is not a neoplastic condition, it is an emerging precursor to neoplastic high-grade B-cell lymphoproliferation among people with HIV, especially for individuals on long-term combination antiretroviral therapy with well controlled HIV.