Objective

To estimate the association between immunologic response to antiretroviral therapy (ART) and non-AIDS defining cancer (NADC) incidence in HIV-infected patients.

Design

A prospective cohort including patients with at least 1 cell/μl CD4 cell count and HIV-1 RNA measure after ART initiation between 1996 and 2011 in the Centers for AIDS Research Network of Integrated Clinical Systems, a collaboration of eight HIV clinics at major academic medical centres in the United States.

Methods

Measures of immunologic response were 6-month CD4 post-ART, latest CD4 and CD4 count-years, a cumulative measure of CD4 lymphopenia. Cox regression with inverse probability-of-exposure weights was used to calculate adjusted hazard ratios of virus-related and virus-unrelated NADC incidence.

Results

Among 9389 patients at ART initiation, median CD4 cell count was 200 cells/μl [interquartile range (IQR) 60-332)], and median HIV-1 RNA was 4.8 log10 copies/ml (IQR 4.3-5.4). Median follow-up was 3.3 years (IQR 1.5-6.5). After 6 months of ART, median CD4 cell count was 304 cells/μl (IQR 163-469). One hundred and sixty-four NADCs were diagnosed during study follow-up, 65 (40%) considered virus-related. Virus-related NADCs were inversely associated with 6-month CD4 cell count (hazard ratio per 100 cells/μl increase=0.71), latest CD4 cell count (hazard ratio per 100 cells/μl increase=0.70) and CD4 cell count-years (hazard ratio per 200 cell-years/μl increase=0.91) independent of CD4 cell count at ART initiation, age and HIV-1 RNA response. No associations were found with virus-unrelated NADCs.

Conclusion

Poor CD4 cell count response was strongly associated with virus-related NADC incidence, suggesting an important role for T-cell mediated immunity in pathogenesis. Lower CD4 cell count proximal to cancer diagnosis may be a result of subclinical cancer. Intensified cancer screening should be considered for patients on ART with low CD4 cell counts.

Background

Esophageal squamous cell carcinoma (ESCC) comprises 90% of all esophageal cancer cases globally and is the most common histology in low-resource settings. Eastern Africa has a disproportionately high incidence of ESCC.

Methods

We describe the genomic profiles of 61 ESCC cases from Tanzania and compare them to profiles from an existing cohort of ESCC cases from Malawi. We also provide a comparison to ESCC tumors in The Cancer Genome Atlas (TCGA).

Results

We observed substantial transcriptional overlap with other squamous histologies via comparison with TCGA PanCan dataset. DNA analysis revealed known mutational patterns, both genome-wide as well as in genes known to be commonly mutated in ESCC. TP53 mutations were the most common somatic mutation in tumors from both Tanzania and Malawi but were detected at lower frequencies than previously reported in ESCC cases from other settings. In a combined analysis, two unique transcriptional clusters were identified: a proliferative/epithelial cluster and an invasive/migrative/mesenchymal cluster. Mutational signature analysis of the Tanzanian cohort revealed common signatures associated with aging and cytidine deaminase activity (APOBEC) and an absence of signature 29, which was previously reported in the Malawi cohort.

Conclusions

This study defines the molecular characteristics of ESCC in Tanzania, and enriches the Eastern African dataset, with findings of overall similarities but also some heterogeneity across two unique sites.

Impact

Despite a high burden of ESCC in Eastern Africa, investigations into the genomics in this region are nascent. This represents the largest comprehensive genomic analysis ESCC from sub-Saharan Africa to date.

Objective

To examine the association between early HIV viremia and mortality after HIV-associated lymphoma.

Design

Multicenter observational cohort study.

Setting

Center for AIDS Research Network of Integrated Clinical Systems cohort.

Participants

HIV-infected patients with lymphoma diagnosed between 1996 and 2011, who were alive 6 months after lymphoma diagnosis and with at least two HIV RNA values during the 6 months after lymphoma diagnosis.

Exposure

Cumulative HIV viremia during the 6 months after lymphoma diagnosis, expressed as viremia copy-6-months.

Main outcome measure

All-cause mortality between 6 months and 5 years after lymphoma diagnosis.

Results

Of 224 included patients, 183 (82%) had non-Hodgkin lymphoma (NHL) and 41 (18%) had Hodgkin lymphoma. At lymphoma diagnosis, 105 (47%) patients were on antiretroviral therapy (ART), median CD4⁺ cell count was 148 cells/μl (interquartile range 54-322), and 33% had suppressed HIV RNA (<400 copies/ml). In adjusted analyses, mortality was associated with older age [adjusted hazard ratio (AHR) 1.37 per decade increase, 95% CI 1.03-1.83], lymphoma occurrence on ART (AHR 1.63, 95% CI 1.02-2.63), lower CD4⁺ cell count (AHR 0.75 per 100 cells/μl increase, 95% CI 0.64-0.89), and higher early cumulative viremia (AHR 1.35 per log₁₀ copies × 6-months/ml, 95% CI 1.11-1.65). The detrimental effect of early cumulative viremia was consistent across patient groups defined by ART status, CD4⁺ cell count, and histology.

Conclusion

Exposure to each additional 1-unit log₁₀ in HIV RNA throughout the 6 months after lymphoma diagnosis was associated with a 35% increase in subsequent mortality. These results suggest that early and effective ART during chemotherapy may improve survival.

Background

The incidence of non-Hodgkin lymphoma (NHL) in human immunodeficiency virus (HIV)-infected patients remains high despite treatment with antiretroviral therapy (ART).

Methods

We evaluated NHL incidence in HIV-infected patients followed in the Centers for AIDS Research Network of Integrated Clinical Systems who started combination ART and achieved suppression of HIV. We estimated the hazard ratio for NHL by time-varying HIV viremia categories, accounting for time-varying CD4 cell count using marginal structural models.

Results

We observed 37 incident NHL diagnoses during 21 607 person-years of follow-up in 6036 patients (incidence rate, 171 per 100 000 person-years; 95% confidence interval [CI], 124-236). NHL incidence was high even among patients with nadir CD4 cell count >200 cells/µL (140 per 100 000 person-years [95% CI, 80-247]). Compared with ≤50 copies/mL, hazard ratios (HRs) for NHL were higher among those with HIV viremia of 51-500 copies/mL (HR current = 1.66 [95% CI, .70-3.94]; HR 3-month lagged = 2.10 [95% CI, .84-5.22]; and HR 6-month lagged = 1.46 [95% CI, .60-3.60]) and >500 copies/mL (HR current = 2.39 [95% CI, .92-6.21]; HR 3-month lagged = 3.56 [95% CI, 1.21-10.49]; and HR 6-month lagged = 2.50 [95% CI, .91-6.84]). Current HIV RNA as a continuous variable was also associated with NHL (HR = 1.42 per log10 copies/mL [95% CI, 1.05-1.92]).

Conclusions

Our findings demonstrate a high incidence of NHL among HIV-infected patients on ART and suggest a role of HIV viremia in the pathogenesis of NHL. Earlier initiation of potent ART and maximal continuous suppression of HIV viremia may further reduce NHL risk.

An estimated 38 million people live with human immunodeficiency virus (HIV) worldwide and are at excess risk for multiple cancer types. Elevated cancer risks in people living with HIV (PLWH) are driven primarily by increased exposure to carcinogens, most notably oncogenic viruses acquired through shared transmission routes, plus acceleration of viral carcinogenesis by HIV-related immunosuppression. In the era of widespread antiretroviral therapy (ART), life expectancy of PLWH has increased, with cancer now a leading cause of co-morbidity and death. Furthermore, the types of cancers occurring among PLWH are shifting over time and vary in their relative burden in different parts of the world. In this context, the International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) convened a meeting in September 2022 of multinational and multidisciplinary experts to focus on cancer in PLWH. This report summarizes the proceedings, including a review of the state of the science of cancer descriptive epidemiology, etiology, molecular tumor characterization, primary and secondary prevention, treatment disparities and survival in PLWH around the world. A consensus of key research priorities and recommendations in these domains is also presented.

Background

Lymphoma is the leading cause of cancer-related death among HIV-infected patients in the antiretroviral therapy (ART) era.

Methods

We studied lymphoma patients in the Centers for AIDS Research Network of Integrated Clinical Systems from 1996 until 2010. We examined differences stratified by histology and diagnosis year. Mortality and predictors of death were analyzed using Kaplan-Meier curves and Cox proportional hazards.

Results

Of 23 050 HIV-infected individuals, 476 (2.1%) developed lymphoma (79 [16.6%] Hodgkin lymphoma [HL]; 201 [42.2%] diffuse large B-cell lymphoma [DLBCL]; 56 [11.8%] Burkitt lymphoma [BL]; 54 [11.3%] primary central nervous system lymphoma [PCNSL]; and 86 [18.1%] other non-Hodgkin lymphoma [NHL]). At diagnosis, HL patients had higher CD4 counts and lower HIV RNA than NHL patients. PCNSL patients had the lowest and BL patients had the highest CD4 counts among NHL categories. During the study period, CD4 count at lymphoma diagnosis progressively increased and HIV RNA decreased. Five-year survival was 61.6% for HL, 50.0% for BL, 44.1% for DLBCL, 43.3% for other NHL, and 22.8% for PCNSL. Mortality was associated with age (adjusted hazard ratio [AHR] = 1.28 per decade increase, 95% confidence interval [CI] = 1.06 to 1.54), lymphoma occurrence on ART (AHR = 2.21, 95% CI = 1.53 to 3.20), CD4 count (AHR = 0.81 per 100 cell/µL increase, 95% CI = 0.72 to 0.90), HIV RNA (AHR = 1.13 per log10copies/mL, 95% CI = 1.00 to 1.27), and histology but not earlier diagnosis year.

Conclusions

HIV-associated lymphoma is heterogeneous and changing, with less immunosuppression and greater HIV control at diagnosis. Stable survival and increased mortality for lymphoma occurring on ART call for greater biologic insights to improve outcomes.

Background

Lymphoma incidence is increased among human immunodeficiency virus (HIV)-infected individuals soon after antiretroviral therapy (ART), perhaps due to unmasking immune reconstitution inflammatory syndrome (IRIS). Clinical characteristics and survival for unmasking lymphoma IRIS have not been described.

Methods

We studied lymphoma patients in the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) from 1996 until 2011. Unmasking lymphoma IRIS was defined as lymphoma within 6 months after ART accompanied by a ≥ 0.5 log10 copies/mL HIV RNA reduction. Differences in presentation and survival were examined between IRIS and non-IRIS cases.

Results

Of 482 lymphoma patients, 56 (12%) met criteria for unmasking lymphoma IRIS. Of these, 12 (21%) had Hodgkin lymphoma, 22 (39%) diffuse large B-cell lymphoma, 5 (9%) Burkitt lymphoma, 10 (18%) primary central nervous system lymphoma, and 7 (13%) other non-Hodgkin lymphoma. Median CD4 cell count at lymphoma diagnosis among IRIS cases was 173 cells/µL (interquartile range, 73-302), and 48% had suppressed HIV RNA <400 copies/mL. IRIS cases were similar overall to non-IRIS cases in histologic distribution and clinical characteristics, excepting more frequent hepatitis B and C (30% vs 19%, P = .05), and lower HIV RNA at lymphoma diagnosis resulting from the IRIS case definition. Overall survival at 5 years was similar between IRIS (49%; 95% confidence interval [CI], 37%-64%) and non-IRIS (44%; 95% CI, 39%-50%), although increased early mortality was suggested among IRIS cases.

Conclusions

In a large HIV-associated lymphoma cohort, 12% of patients met a uniformly applied unmasking lymphoma IRIS case definition. Detailed studies of lymphoma IRIS might identify immunologic mechanisms of lymphoma control.

Background

Cancer is an important cause of morbidity and mortality in individuals infected with human immunodeficiency virus (HIV), but patterns of cancer incidence after combination antiretroviral therapy (ART) initiation remain poorly characterized.

Methods

We evaluated the incidence and timing of cancer diagnoses among patients initiating ART between 1996 and 2011 in a collaboration of 8 US clinical HIV cohorts. Poisson regression was used to estimate incidence rates. Cox regression was used to identify demographic and clinical characteristics associated with cancer incidence after ART initiation.

Results

At initiation of first combination ART among 11 485 patients, median year was 2004 (interquartile range [IQR], 2000-2007) and median CD4 count was 202 cells/mm(3) (IQR, 61-338). Incidence rates for Kaposi sarcoma (KS) and lymphomas were highest in the first 6 months after ART initiation (P < .001) and plateaued thereafter, while incidence rates for all other cancers combined increased from 416 to 615 cases per 100 000 person-years from 1 to 10 years after ART initiation (average 7% increase per year; 95% confidence interval, 2%-13%). Lower CD4 count at ART initiation was associated with greater risk of KS, lymphoma, and human papillomavirus-related cancer. Calendar year of ART initiation was not associated with cancer incidence.

Conclusions

KS and lymphoma rates were highest immediately following ART initiation, particularly among patients with low CD4 cell counts, whereas other cancers increased with time on ART, likely reflecting increased cancer risk with aging. Our results underscore recommendations for earlier HIV diagnosis followed by prompt ART initiation along with ongoing aggressive cancer screening and prevention efforts throughout the course of HIV care.

The incidence of esophageal squamous cell carcinoma (ESCC) is disproportionately high in the eastern corridor of Africa and parts of Asia. Emerging research has identified a potential association between poor oral health and ESCC. One possible link between poor oral health and ESCC involves the alteration of the microbiome. We performed an integrated analysis of four independent sequencing efforts of ESCC tumors from patients from high- and low-incidence regions of the world. Using whole genome sequencing (WGS) and RNA sequencing (RNAseq) of ESCC tumors from 61 patients in Tanzania, we identified a community of bacteria, including members of the genera Fusobacterium, Selenomonas, Prevotella, Streptococcus, Porphyromonas, Veillonella and Campylobacter, present at high abundance in ESCC tumors. We then characterized the microbiome of 238 ESCC tumor specimens collected in two additional independent sequencing efforts consisting of patients from other high-ESCC incidence regions (Tanzania, Malawi, Kenya, Iran, China). This analysis revealed similar ESCC-associated bacterial communities in these cancers. Because these genera are traditionally considered members of the oral microbiota, we next explored whether there was a relationship between the synchronous saliva and tumor microbiomes of ESCC patients in Tanzania. Comparative analyses revealed that paired saliva and tumor microbiomes were significantly similar with a specific enrichment of Fusobacterium and Prevotella in the tumor microbiome. Together, these data indicate that cancer-associated oral bacteria are associated with ESCC tumors at the time of diagnosis and support a model in which oral bacteria are present in high abundance in both saliva and tumors of some ESCC patients.