Clinico-pathological characteristics among South African women with breast cancer receiving anti-retroviral therapy for HIV

FGFR2 genetic variants in women with breast cancer

Black African populations are more genetically diverse than others, but genetic variants have been studied primarily in European populations. The present study examined the association of four single nucleotide polymorphisms (SNPs) of the fibroblast growth factor receptor 2, associated with breast cancer in non‑African populations, with breast cancer in Black, southern African women. Genomic DNA was extracted from whole blood samples of 1,001 patients with breast cancer and 1,006 controls (without breast cancer), and the rs2981582, rs35054928, rs2981578, and rs11200014 polymorphisms were analyzed using allele‑specific Kompetitive allele‑specific PCR™, and the χ2 or Fisher's exact tests were used to compare the genotype frequencies. There was no association between those SNPs and breast cancer in the studied cohort, although an association was identified between the C/C homozygote genotype for rs2981578 and invasive lobular carcinoma. These results show that genetic biomarkers of breast cancer risk in European populations are not necessarily associated with risk in sub‑Saharan African populations. African populations are more heterogenous than other populations, and the information from this population can help focus genetic risks of cancer in this understudied population.

PAM50 intrinsic subtypes, risk of recurrence score and breast cancer survival in HIV-positive and HIV-negative patients-a South African cohort study

PURPOSE

Treatment decision making for patients with breast cancer increasingly depends on analysis of markers or systems for estimating risk of breast cancer recurrence. Breast cancer intrinsic subtypes and risk of recurrence (ROR) scores have been found to be valuable in predicting survival and determining optimal treatment for individual patients. We studied the association of breast cancer survival with the PAM50 gene expression assay in HIV-positive and HIV-negative patients.

METHOD

RNA was extracted from formalin-fixed paraffin-embedded specimens of histologically confirmed invasive carcinoma and was purified using the AllPrep® DNA/RNA FFPE kit, Qiagen (Hilden, Germany). The NanoString RUO PAM50 algorithm was used to determine the molecular subtype and the risk of recurrence score of each sample. The overall and disease-free survival were determined with comparison made among HIV-positive and -negative patients. We then generated Kaplan-Meier survival curves, calculated p-values and estimated hazard ratios and their 95% confidence intervals using Cox regression models.

RESULTS

Of the 384 RNA samples analysed, 98.4% met the required RNA quality standard and the specified QC threshold for the test. Luminal B was the most common PAM50 intrinsic subtype and 82.1% of patients were at high risk for disease recurrence based on ROR score. HIV infection, PAM50-based HER2-enriched and basal-like intrinsic subtypes, and high ROR were associated with poor overall and disease-free survival. HIV-positive patients with luminal A & B subtypes had significantly worse survival outcomes than HIV-negative luminal patents.

CONCLUSION

Aggressive tumour biology was common in our cohort. HIV infection, PAM50 HER2-enriched,basal-like intrinsic subtypes and high ROR score were associated with poor overall and disease-free survival. HIV infection impacted survival in patients with luminal subtypes only.

Discordance between PAM50 intrinsic subtyping and immunohistochemistry in South African women with breast cancer

PURPOSE

Breast cancer is a heterogeneous disease with different gene expression profiles, treatment options and outcomes. In South Africa, tumors are classified using immunohistochemistry. In high-income countries multiparameter genomic assays are being utilized with implications for tumor classification and treatment.

METHODS

In a cohort of 378 breast cancer patients from the SABCHO study, we investigated the concordance between tumor samples classified by IHC and the PAM50 gene assay.

RESULTS

IHC classified patients as ER-positive (77.5%), PR-positive (70.6%), and HER2-positive (32.3%). These results, together with Ki67, were used as surrogates for intrinsic subtyping, and showed 6.9% IHC-A-clinical, 72.7% IHC-B-clinical, 5.3% IHC-HER2-clinical and 15.1% triple negative cancer (TNC). Typing using the PAM50 gave 19.3% luminal-A, 32.5% luminal-B, 23.5% HER2-enriched and 24.6% basal-like. The basal-like and TNC had the highest concordance, while the luminal-A and IHC-A group had the lowest concordance. By altering the cutoff for Ki67, and realigning the HER2/ER/PR-positive patients to IHC-HER2, we improved concordance with the intrinsic subtypes.

CONCLUSION

We suggest that the Ki67 be changed to a cutoff of 20-25% in our population to better reflect the luminal subtype classifications. This change would inform treatment options for breast cancer patients in settings where genomic assays are unaffordable.

A Review of the Nucleic Acid-Based Lateral Flow Assay for Detection of Breast Cancer from Circulating Biomarkers at a Point-of-Care in Low Income Countries

The current levels of breast cancer in African women have contributed to the high mortality rates among them. In South Africa, the incidence of breast cancer is also on the rise due to changes in behavioural and biological risk factors. Such low survival rates can be attributed to the late diagnosis of the disease due to a lack of access and the high costs of the current diagnostic tools. Breast cancer is asymptomatic at early stages, which is the best time to detect it and intervene to prevent high mortality rates. Proper risk assessment, campaigns, and access to adequate healthcare need to be prioritised among patients at an early stage. Early detection of breast cancer can significantly improve the survival rate of breast cancer patients, since therapeutic strategies are more effective at this stage. Early detection of breast cancer can be achieved by developing devices that are simple, sensitive, low-cost, and employed at point-of-care (POC), especially in low-income countries (LICs). Nucleic-acid-based lateral flow assays (NABLFAs) that combine molecular detection with the immunochemical visualisation principles, have recently emerged as tools for disease diagnosis, even for low biomarker concentrations. Detection of circulating genetic biomarkers in non-invasively collected biological fluids with NABLFAs presents an appealing and suitable method for POC testing in resource-limited regions and/or LICs. Diagnosis of breast cancer at an early stage will improve the survival rates of the patients. This review covers the analysis of the current state of NABLFA technologies used in developing countries to reduce the scourge of breast cancer.

Impact of HIV infection on survival among women with stage I-III breast cancer: Results from the South African breast cancer and HIV outcomes study

In some countries of sub-Saharan Africa, the prevalence of HIV exceeds 20%; in South Africa, 20.4% of people are living with HIV. We examined the impact of HIV infection on the overall survival (OS) of women with nonmetastatic breast cancer (BC) enrolled in the South African Breast Cancer and HIV Outcomes (SABCHO) study. We recruited women with newly diagnosed BC at six public hospitals from 1 July 2015 to 30 June 2019. Among women with stages I-III BC, we compared those with and without HIV infection on sociodemographic, clinical, and treatment factors. We analyzed the impact of HIV on OS using multivariable Cox proportional hazard models. Of 2367 women with stages I-III BC, 499 (21.1%) had HIV and 1868 (78.9%) did not. With a median follow-up of 29 months, 2-year OS was poorer among women living with HIV (WLWH) than among HIV-uninfected women (72.4% vs 80.1%, P < .001; adjusted hazard ratio (aHR) 1.49, 95% confidence interval (CI) = 1.22-1.83). This finding was consistent across age groups ≥45 years and <45 years, stage I-II BC and stage III BC, and ER/PR status (all P < .03). Both WLWH with <50 viral load copies/mL and WLWH with ≥50 viral load copies/mL had poorer survival than HIV-uninfected BC patients [aHR: 1.35 (1.09-1.66) and 1.54 (1.20-2.00), respectively], as did WLWH who had ≥200 CD4+ cells/mL at diagnosis [aHR: 1.39 (1.15-1.67)]. Because receipt of antiretroviral therapy has become widespread, WLWH is surviving long enough to develop BC; more research is needed on the causes of their poor survival.

Disparities in breast cancer survival between women with and without HIV across sub-Saharan Africa (ABC-DO): a prospective, cohort study

BACKGROUND

Studies have shown increased mortality among women living with HIV diagnosed with breast cancer compared with HIV-negative women with breast cancer. We aimed to examine how this HIV differential varies by patient or breast tumour characteristics.

METHODS

The African Breast Cancer-Disparities in Outcomes (ABC-DO) study is a prospective cohort of women (aged ≥18 years) with incident breast cancer recruited consecutively at diagnosis (2014-17) from hospitals in Namibia, Nigeria, South Africa, Uganda, and Zambia. Detailed clinical and epidemiological data, including self-reported or tested HIV status, were collected at baseline. Participants were actively followed up via telephone calls every 3 months. The primary outcome was all-cause mortality, assessed in all women who had at least one updated vital status after baseline interview. Using Cox regression, we examined differences in overall survival by HIV status in the cohort, and across country and patient subgroups, adjusted for age, tumour grade, and tumour stage at cancer diagnosis.

FINDINGS

Between Sept 8, 2014, and Dec 31, 2017, we recruited 2154 women with primary breast cancer, 519 of whom were excluded due to their countries having small numbers of women with HIV for comparison. Among the remaining 1635 women, 313 (19%) were living with HIV, 1184 (72%) were HIV negative, and 138 (9%) had unknown HIV status. At breast cancer diagnosis, women with HIV were younger and had lower body-mass index (BMI) than their HIV-negative counterparts, but had similar tumour stage, grade, and receptor subtypes. At the end of the follow-up (Jan 1, 2019), a higher proportion of women with HIV (137 [44%] of 313) had died than had HIV-negative women (432 [37%] of 1184). Crude 3-year survival was 9% lower for women with HIV (46% [95% CI 40-53]) than for HIV-negative women (55% [52-59]; hazard ratio (HR) 1·41 [1·15-1·74]). The HIV survival differential did not differ by age, BMI, tumour subtype, or tumour grade, but was stronger in women with non-metastatic disease (3-year survival 52% HIV-positive vs 63% HIV-negative women, adjusted HR 1·65 [1·30-2·10]), whereas women with metastatic cancer had low survival, regardless of HIV status.

INTERPRETATION

The larger survival deficit among women with HIV with non-metastatic breast cancer calls for a better understanding of the reasons underlying this differential (eg, biological mechanisms, health behaviours, detrimental HIV-breast cancer treatment interactions, or higher HIV background mortality) to inform strategies for reducing mortality among this patient group.

FUNDING

Susan G Komen, International Agency for Research on Cancer, National Cancer Institute, and UK-Commonwealth Scholarships.

Survival of south african women with breast cancer receiving anti-retroviral therapy for HIV

PURPOSE

Breast cancer outcomes in sub-Saharan Africa is reported to be poor, with an estimated five-year survival of 50% when compared to almost 90% in high-income countries. Although several studies have looked at the effect of HIV in breast cancer survival, the effect of ARTs has not been well elucidated.

METHODS

All females newly diagnosed with invasive breast cancer from May 2015-September 2017 at Charlotte Maxeke Johannesburg Academic and Chris Hani Baragwanath Academic Hospital were enrolled. We analysed overall survival and disease-free survival, comparing HIV positive and negative patients. Kaplan-Meier survival curves were generated with p-values calculated using a log-rank test of equality while hazard ratios and their 95% confidence intervals (CIs) were estimated using Cox regression models.

RESULTS

Of 1019 patients enrolled, 22% were HIV positive. The overall survival (95% CI) was 53.5% (50.1-56.7%) with a disease-free survival of 55.8% (52.1-59.3) after 4 years of follow up. HIV infection was associated with worse overall survival (HR (95% CI): 1.50 (1.22-1.85), p < 0.001) and disease-free survival (OR (95% CI):2.63 (1.71-4.03), p < 0.001), especially among those not on ART at the time of breast cancer diagnosis. Advanced stage of the disease and hormone-receptor negative breast cancer subtypes were also associated with poor survival.

CONCLUSION

HIV infection was associated with worse overall and disease-free survival. HIV patients on ARTs had favourable overall and disease-free survival and with ARTs now being made accessible to all the outcome of women with HIV and breast cancer is expected to improve.

Impact of HIV infection on overall survival among women with stage IV breast cancer in South Africa

PURPOSE

Advanced breast cancer (BC) at diagnosis is common in sub-Saharan Africa (SSA), including among women living with HIV (WLWH). In public hospitals across South Africa (SA), 10-15% of women present with stage IV BC, compared to < 5% in the United States (US); 20% of new BC diagnoses in SA are in WLWH. We evaluated the impact of HIV on overall survival (OS) among women with stage IV BC.

METHODS

We conducted a prospective cohort study of women diagnosed with stage IV BC between February 2, 2015 and September 18, 2019 at six public hospitals in SA. Multivariate Cox regression models were used to estimate the association between HIV status and OS.

RESULTS

Among 550 eligible women, 147 (26.7%) were WLWH. Compared to HIV-negative BC patients, WLWH were younger (median age 45 vs. 60 years, p < 0.001), predominantly black (95.9% vs. 77.9%, p < 0.001), and more likely to have hormone receptor-negative (hormone-negative) BC (32.7% vs. 22.6%, p = 0.016). Most women received systemic cancer-directed therapy (80.1%). HIV status was not associated with treatment or OS (Hazard Ratio (HR) 1.13 [95%CI 0.89-1.44]). On exploratory subgroup analysis, WLWH and hormone-negative BC had shorter OS compared to HIV-uninfected women (1-year OS: 27.1% vs. 48.8%, p = 0.003; HR 1.94 [95%CI 1.27-2.94]; p = 0.002), which was not observed for hormone receptor-positive BC.

CONCLUSION

HIV status was not associated with worse OS in women with stage IV BC in SA and cannot account for the poor survival in this cohort. Subgroup analysis revealed that WLWH with hormone-negative BC had worse OS, which warrants further investigation.

Impact of HIV infection on baseline characteristics and survival of women with breast cancer

BACKGROUND

As women living with HIV (WLWH) become older, their risk of developing breast cancer increases. Nonetheless, literature is conflicting regarding tumor stage, distribution of subtypes and overall survival among WLWH vs. HIV-negative women with breast cancer. We assessed differences in clinicopathological characteristics and overall survival between these two groups.

METHODS

Systematic review and meta-analysis using MEDLINE, Scopus, ISI Web of Knowledge, LILACS, SciELO and conference abstracts up to 1 January 2020. Cross-sectional/cohort studies comparing baseline characteristics (stage and/or subtypes) and/or overall survival of WLWH vs. HIV-negative women with breast cancer were included. We performed random-effects meta-analyses to estimate summary statistics and subgroup analyses according to region of the world.

RESULTS

Eighteen studies [4 from North America, 14 from sub-Saharan Africa (SSA)] were included, with 3174 WLWH and 2 394 598 HIV-negative women. WLWH from North America and SSA were more likely to present with stage III/IV disease compared with HIV-negative women - pooled odds ratio (pOR) 1.76 [95% confidence interval (CI):1.58-1.95] and pOR 1.23 (95% CI: 1.06-1.42), respectively. WLWH from SSA were also less likely to have estrogen receptor-positive/HER2-negative tumors (pOR 0.81; 95% CI: 0.66-0.99). After adjustment, WLWH had worse overall survival compared with HIV-negative women, both in North America [pooled adjusted hazard ratio (aHR) 2.45; 95% CI: 1.11-5.41] and SSA (aHR 1.43; 95% CI: 1.06-1.92).

CONCLUSION

Compared with HIV-negative women, WLWH are diagnosed with breast cancer at a more advanced stage and have a worse overall survival. These results should raise awareness regarding the detection and survival gap among WLWH with breast cancer and further studies are needed to decipher the reasons behind these disparities.

Impact of Antiretroviral Therapy on Cancer Treatment Outcomes among People Living with HIV in Low- and Middle-Income Countries: a Systematic Review

PURPOSE OF REVIEW

The relationship between antiretroviral therapy (ART) and cancer treatment outcomes among people living with HIV (PLWH) in low- and middle-income countries (LMICs) is complex and poorly understood for many cancers. We aimed to summarize existing evidence from LMICs regarding the benefit of ART on cancer treatment-related outcomes.

RECENT FINDINGS

We included twelve observational studies that reported associations between ART status and cancer treatment outcomes among HIV-positive patients in LMICs. Most confirmed ART was associated with improved cancer treatment outcomes. Heterogeneity in cancers under study, outcome measurement, categorization of ART status, and reporting of HIV-related immune function made formal comparison between studies untenable. Where evaluated, ART generally has a positive effect on cancer outcomes in people with HIV in LMICs. However, there remains a substantial gap in the literature regarding the impact of ART on treatment outcomes for most cancer types. Future research should focus on the optimal timing and integration of ART and cancer treatment for PLWH with strategies applicable to constrained-resource settings.