Living longer with HIV: what does it mean for cancer risk?

Disparities and Determinants of Cancer Treatment in Elderly Americans Living With Human Immunodeficiency Virus/AIDS

Background

Previous studies suggest that human immunodeficiency virus (HIV)-infected cancer patients are less likely to receive cancer treatment. The extent to which this disparity affects the growing population of elderly individuals is unknown and factors that mediate these treatment differences have not been explored.

Methods

We studied 930359 Americans aged 66-99 years who were diagnosed with 10 common cancers. Surveillance, Epidemiology, and End Results-Medicare claims from 1991 to 2011 were used to determine HIV status and receipt of cancer treatment in 6 months following diagnosis. Mediation analysis was conducted to estimate the direct effect of HIV, and indirect effect through cancer stage at diagnosis and comorbidities, on cancer treatment.

Results

HIV-infected individuals (n = 687) were less likely to receive cancer treatment (70% vs 75% HIV uninfected; P < .01). This difference was larger in individuals aged 66-70 years, among whom only 65% were treated (vs 81% in HIV uninfected; P < .01), and time from cancer diagnosis to treatment was longer (median, 42.5 vs 36 days in HIV uninfected; P < .01). Accounting for potential confounders, HIV-infected individuals aged 66-70 years remained 20% less likely to receive cancer treatment (hazard ratio, 0.81 [95% confidence interval, .71-.92]). Seventy-five percent of this total effect was due to HIV itself, with a nonsignificant 24% mediated by cancer stage and comorbidities.

Conclusions

Lowest cancer treatment rates were seen in the younger subset of HIV-infected individuals, who would likely benefit most from treatment in terms of life expectancy.

Epstein-Barr virus-driven lymphomagenesis in the context of human immunodeficiency virus type 1 infection

Epstein-Barr virus (EBV) is a ubiquitous human γ-herpes virus which establishes a life-long asymptomatic infection in immunocompetent hosts. In human immunodeficiency virus type 1 (HIV-1) infected patients, the impaired immunosurveillance against EBV may favor the development of EBV-related diseases, ranging from lymphoproliferative disorders to B cell non-Hodgkin's lymphomas (NHL). Antiretroviral therapy (ART) has significantly modified the natural course of HIV-1 infection, resulting in decreased HIV-1 plasmaviremia, increased CD4 lymphocytes, and decreased opportunistic infections, indicating a restoration of immune functions. However, the impact of ART appears to be less favorable on EBV-related malignancies than on other AIDS-defining tumors, such as Kaposi's sarcoma, and NHL remains the most common cancer during the ART era. EBV-driven tumors are associated with selective expression of latent oncogenic proteins, but uncontrolled lytic cycle with virus replication and/or reactivation may favor cell transformation, at least in the early phases. Several host's factors may promote EBV reactivation and replication; besides immunodepression, inflammation/chronic immune stimulation may play an important role. Microbial pathogen-associated molecular patterns and endogenous damage-associated molecular patterns, through Toll-like receptors, activate the immune system and may promote EBV reactivation and/or polyclonal expansion of EBV-infected cells. A body of evidence suggests that chronic immune stimulation is a hallmark of HIV-1 pathogenesis and may persist even in ART-treated patients. This review focuses on lymphomagenesis driven by EBV both in the context of the natural history of HIV-1 infection and in ART-treated patients. Understanding the mechanisms involved in the expansion of EBV-infected cells is a premise for the identification of prognostic markers of EBV-associated malignancies.

Malignancies in HIV/AIDS patients attending an outpatient clinic in Vitória, State of Espírito Santo, Brazil

INTRODUCTION

The present study investigated cancer prevalence and associated factors among HIV-infected individuals attending an AIDS outpatient clinic in Vitória, State of Espírito Santo, Brazil.

METHODS

A sectional study was conducted among HIV infected adults attending an AIDS outpatient clinic in Vitória, State of Espírito Santo, Brazil. Demographic, epidemiological and clinical data were abstracted from medical records, including cancer diagnoses; nadir and current CD4 cell count, HIV viral load, time on antiretroviral treatment (ART), type of ART and smoking status.

RESULTS

A total of 730 (91.3%) patients were included in the study. Median age was 44.0 [interquartile range (IQR): 35-50.3] years; median time since HIV diagnosis was 5.5 years (IQR: 2-10); 60% were male; and 59% were white. Thirty (4.1%) cases of cancer were identified of which 16 (53%) were AIDS defining cancers and 14 (47%) were non-AIDS defining malignancies. Patients diagnosed with cancer presented higher chance of being tobacco users [OR 2.2 (95% CI: 1.04-6.24)]; having nadir CD4 ≤200 cells/mm³ [OR 3.0 (95% CI: 1.19-7.81)] and higher lethality [OR 13,3 (95% CI: 4,57-38,72)].

CONCLUSIONS

These results corroborate the importance of screening for and prevention of non-AIDS defining cancers focus in HIV-infected population, as these cancers presented with similar frequency as AIDS defining cancers.

HIV and cancer in Africa: mutual collaboration between HIV and cancer programs may provide timely research and public health data

The eruption of Kaposi sarcoma (KS) and aggressive non-Hodgkin lymphoma (NHL) in young homosexual men in 1981 in the West heralded the onset of the human immunodeficiency virus (HIV) infection epidemic, which remains one of the biggest challenges to global public health and science ever. Because KS and NHL were increased >10,000 and 50-600 times, respectively, with HIV, they were designated AIDS defining cancers (ADC). Cervical cancer (CC), increased 5-10 times was also designated as an ADC. A few other cancers are elevated with HIV, including Hodgkin lymphoma (10 times), anal cancer (15-30 times), and lung cancer (4 times) are designated as non-AIDS defining cancers (NADCs). Since 1996 when combination antiretroviral therapy (cART) became widely available in the West, dramatic decreases in HIV mortality have been observed and substantial decrease in the incidence of ADCs. Coincidentally, the burden of NADCs has increased as people with HIV age with chronic HIV infection. The impact of HIV infection on cancer in sub-Saharan Africa, where two thirds of the epidemic is concentrated, remains poorly understood. The few studies conducted indicate that risks for ADCs are also increased, but quantitatively less so than in the West. The risks for many cancers with established viral associations, including liver and nasopharynx, which are found in Africa, do not appear to be increased. These data are limited because of competing mortality, and cancer is under diagnosed, pathological confirmation is rare, and cancer registration not widely practiced. The expansion of access to life-extending cART in sub-Saharan Africa, through programs such as the Global Fund for AIDS, Malaria, and Tuberculosis and the US President's Emergency Program for AIDS Relief (PEPFAR), is leading to dramatic lengthening of life of HIV patients, which will likely influence the spectrum and burden of cancer in patients with HIV. In this paper, we review current literature and explore merits for integrating cancer research in established HIV programs to obtain timely data about the incidence and burden of cancer in HIV-infected persons in Africa.

Cancer incidence in the multicenter AIDS Cohort Study before and during the HAART era: 1984 to 2007

BACKGROUND

The incidence of Kaposi sarcoma (KS) and non-Hodgkin lymphoma (NHL) among human immunodeficiency virus (HIV)-infected individuals declined after the introduction of highly active antiretroviral therapy (HAART) in the mid-1990s, but the cancer risk associated with HIV infection during the HAART era remains to be clarified.

METHODS

Cancer incidence among HIV-infected and HIV-uninfected participants in the Multicenter AIDS (acquired immunodeficiency syndrome) Cohort Study (MACS) between 1984 and 2007 was compared with the expected incidence using US population-based data from the Surveillance, Epidemiology, and End Results (SEER) program. Age- and race-adjusted cancer incidence rates were also compared HIV by status and over time within the MACS. Exact statistical methods were used for all analyses.

RESULTS

A total of 933 incident cancers were observed during 77,320 person-years of follow-up. Compared with SEER, MACS HIV-infected men had significantly (P<.05) elevated rates of KS (standardized incidence ratio [SIR], 139.10), NHL (SIR, 36.80), Hodgkin lymphoma (HL)(SIR, 7.30), and anal cancer (SIR, 25.71). Within MACS, HIV infection was found to be independently associated with each of these cancers across the entire follow-up period, and KS (incidence rate ratio [IRR], 54.93), NHL (IRR, 11.18), and anal cancer (IRR, 18.50) were each found to be significantly elevated among HIV-infected men during the HAART era. Among these men, the incidence of KS and NHL declined (IRR, 0.13 and 0.23, respectively), the incidence of anal cancer increased (IRR, 5.84), and the incidence of HL remained statistically unchanged (IRR, 0.75) from the pre-HAART to the HAART era.

CONCLUSIONS

Cancer risk remains elevated among HIV-infected men who have sex with men, highlighting the continuing need for appropriate cancer screening in this population.