Multimorbidity and overall survival among women with breast cancer: results from the South African Breast Cancer and HIV Outcomes Study.

BACKGROUND: Breast cancer survival in South Africa is low, but when diagnosed with breast cancer, many women in South Africa also have other chronic conditions. We investigated the impact of multimorbidity (≥ 2 other chronic conditions) on overall survival among women with breast cancer in South Africa. METHODS: Between 1 July 2015 and 31 December 2019, we enrolled women newly diagnosed with breast cancer at six public hospitals participating in the South African Breast Cancer and HIV Outcomes (SABCHO) Study. We examined seven chronic conditions (obesity, hypertension, diabetes, HIV, cerebrovascular diseases (CVD), asthma/chronic obstructive pulmonary disease, and tuberculosis), and we compared socio-demographic, clinical, and treatment factors between patients with and without each condition, and with and without multimorbidity. We investigated the association of multimorbidity with overall survival using multivariable Cox proportional hazard models. RESULTS: Of 3,261 women included in the analysis, 45% had multimorbidity; obesity (53%), hypertension (41%), HIV (22%), and diabetes (13%) were the most common individual conditions. Women with multimorbidity had poorer overall survival at 3 years than women without multimorbidity in both the full cohort (60.8% vs. 64.3%, p = 0.036) and stage groups: stages I-II, 80.7% vs. 86.3% (p = 0.005), and stage III, 53.0% vs. 59.4% (p = 0.024). In an adjusted model, women with diabetes (hazard ratio (HR) = 1.20, 95% confidence interval (CI) = 1.03-1.41), CVD (HR = 1.43, 95% CI = 1.17-1.76), HIV (HR = 1.21, 95% CI = 1.06-1.38), obesity + HIV (HR = 1.24 95% CI = 1.04-1.48), and multimorbidity (HR = 1.26, 95% CI = 1.13-1.40) had poorer overall survival than women without these conditions. CONCLUSIONS: Irrespective of the stage, multimorbidity at breast cancer diagnosis was an important prognostic factor for survival in our SABCHO cohort. The high prevalence of multimorbidity in our cohort calls for more comprehensive care to improve outcomes for South African women with breast cancer.

The Impact of HIV Infection on Neoadjuvant and Adjuvant Chemotherapy Relative Dose Intensity in South African Patients with Breast Cancer.

INTRODUCTION: In the South African Breast Cancer and HIV Outcomes (SABCHO) study, we previously found that breast cancer patients living with HIV and treated with neoadjuvant chemotherapy achieve lower rates of complete pathologic response than patients without HIV. We now assess the impact of comorbid HIV on receipt of timely and complete neoadjuvant and adjuvant chemotherapy. MATERIALS AND METHODS: Since June 2015, the SABCHO study has collected data on women diagnosed with breast cancer at 6 South African hospitals. We selected a sample of participants with stages I-III cancer who received ≥2 doses of neoadjuvant or adjuvant chemotherapy. Data on chemotherapies prescribed and received, filgrastim receipt, and laboratory values measured during treatment were captured from patients' medical records. We calculated the mean relative dose intensity (RDI) for all prescribed chemotherapies. We tested for association between full regimen RDI and HIV status, using linear regression to control for demographic and clinical covariates, and for association of HIV with laboratory abnormalities. RESULTS: The 166 participants living with HIV and 159 without HIV did not differ in median chemotherapy RDI: 0.89 (interquartile range (IQR) 0.77-0.95) among those living with HIV and 0.87 (IQR 0.77-0.94) among women without HIV. Patients living with HIV experienced more grade 3+ anemia and leukopenia than those without HIV (anemia: 10.8% vs. 1.9%, P = .001; leukopenia: 8.4% vs. 1.9%, P = .008) and were more likely to receive filgrastim (24.7% vs. 10.7%, P = .001). CONCLUSIONS: HIV status did not impact neoadjuvant or adjuvant chemotherapy RDI, although patients with breast cancer living with HIV experienced more myelotoxicity during treatment.

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.

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.

The impact of HIV on non-adherence for tamoxifen among women with breast cancer in South Africa.

PURPOSE: Women living with HIV (WLWH) and breast cancer (BC) have worse overall survival than HIV-negative women with BC, and poor adherence to prescribed tamoxifen is known to contribute to poor survival. We therefore investigated the association of HIV infection with adherence to adjuvant tamoxifen among women with localized hormone receptor (HR)-positive breast cancer in South Africa. METHODS: Among 4,097 women diagnosed with breast cancer at six hospitals in the prospective South African Breast Cancer and HIV Outcomes (SABCHO) cohort study between July 2015 and December 2020, we focused on black women with stages I-III HR-positive breast cancer who were prescribed 20 mg of adjuvant tamoxifen daily. We collected venous blood once from each participant during a routine clinic visit, and analyzed concentrations of tamoxifen and its metabolites using a triple quadruple mass spectrometer. We defined non-adherence as a tamoxifen level < 60 ng/mL after 3 months of daily tamoxifen use. We compared tamoxifen-related side effects, and concurrent medication use among women with and without HIV and developed multivariable logistic regression models of tamoxifen non-adherence. RESULTS: Among 369 subjects, 78 (21.1%) were WLWH and 291 (78.9%) were HIV-negative. After a median (interquartile range) time of 13.0 (6.2-25.2) months since tamoxifen initiation, the tamoxifen serum concentration ranged between 1.54 and 943.0 ng/mL and 208 (56.4%) women were non-adherent to tamoxifen. Women < 40 years of age were more likely to be non-adherent than women > 60 years (73.4% vs 52.6%, odds ratio (OR) = 2.49, 95% confidence interval (CI) = 1.26-4.94); likewise, WLWH (70.5% vs 52.6%, OR = 2.16, 95% CI = 1.26-3.70) than HIV-negative women. In an adjusted model WLWH had twice the odds of non-adherence to tamoxifen, compared to HIV-negative women (OR = 2.40, 95% CI = 1.11-5.20). CONCLUSION: High rates of non-adherence to adjuvant tamoxifen may limit the overall survival of black South African women with HR-positive breast cancer, especially among WLWH.

Treatment guideline concordance, initiation, and abandonment in patients with non-metastatic breast cancer from the African Breast Cancer-Disparities in Outcomes (ABC-DO) cohort in sub-Saharan Africa: a prospective cohort study.

BACKGROUND: Comprehensive breast cancer management is essential to achieve high breast cancer survival; however, detailed reports of the treatment regimens received by patients are scarce in sub-Saharan Africa where survival is low. We aimed to examine treatment initiation, guideline concordance, and abandonment in patients with non-metastatic breast cancer in sub-Saharan Africa from the African Breast Cancer-Disparities in Outcomes (ABC-DO) prospective cohort. METHODS: The ABC-DO prospective cohort study recruited women (aged ≥18 years) with newly diagnosed invasive breast cancer in eight hospitals across five sub-Saharan African countries (Namibia, Nigeria, Uganda, South Africa, and Zambia). We analysed treatments received by women who were classified as non-metastatic (M0) at the initial presentation. Data on surgery, radiotherapy, and systemic therapies were obtained from medical records and a self-reported follow-up questionnaire at 6 months after the diagnosis, follow-up calls every 3 months, and a baseline questionnaire. Initiation, completion, and abandonment of treatment modalities and combined therapy regimens were examined overall, by country-specific groups, and by clinical factors relevant for guideline-based treatment. FINDINGS: Of 2313 women recruited into the ABC-DO study between Sept 10, 2014, and Dec 31, 2017, 2226 had histologically or clinically confirmed breast cancer. Of these 2226 women, 510 were excluded from the present analysis because 378 had metastatic disease, 37 were prevalent cases (defined as those previously diagnosed with breast cancer >2 years before baseline), 82 had unknown TNM stage, and 13 were White or Asian women in South Africa (number was too small for analysis). After a median follow-up of 5·2 years (IQR 4·6-5·9), 1163 (68%) of 1716 women underwent breast cancer surgery. Surgery and systemic therapy (ie, multimodality treatment) with radiotherapy was initiated in 370 (36%) of 1028 women with localised tumours versus 156 (23%) of 688 women with locally advanced tumours, whereas multimodality treatment without radiotherapy was initiated in 386 (38%) versus 167 (24%) women, respectively. Of 1530 patients requiring chemotherapy (which excludes 105 who died within 6 months after baseline), 1013 (66%) initiated treatment of neoadjuvant chemotherapy or surgery within 3 months after baseline, which was adequately completed by 359 (35%) of 1013 women, marginally completed by 284 (28%), abandoned by 200 (20%), and unknown in 151 (15%). 19 (2%) women died within 6 months after chemotherapy initiation. Of 1375 women in whom endocrine therapy was indicated, this treatment was initiated in 920, and lasted at least 3 years in 367 (40%) women. Treatment disparities between country-specific groups were substantial for all therapy regimens. INTERPRETATION: A high proportion of patients with non-metastatic breast cancer did not initiate, did not fully complete, or abandoned treatment with surgery, systemic therapy, radiotherapy, or an appropriate combination of these, highlighting the need for improved treatment access and completion in sub-Saharan Africa to potentially prevent premature breast cancer deaths. FUNDING: National Institutes of Health (National Cancer Institute), Susan G Komen, and the International Agency for Research on 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.

The Impact of Breast Cancer Treatment Delays on Survival Among South African Women.

BACKGROUND: In high-income settings, delays from breast cancer (BC) diagnosis to initial treatment worsen overall survival (OS). We examined how time to BC treatment initiation (TTI) impacts OS in South Africa (SA). METHODS: We evaluated women enrolled in the South African BC and HIV Outcomes study between July 1, 2015 and June 30, 2019, selecting women with stages I-III BC who received surgery and chemotherapy. We constructed a linear regression model estimating the impact of sociodemographic and clinical factors on TTI and separate multivariable Cox proportional hazard models by first treatment (surgery and neoadjuvant chemotherapy (NAC)) assessing the effect of TTI (in 30-day increments) on OS. RESULTS: Of 1260 women, 45.6% had upfront surgery, 54.4% had NAC, and 19.5% initiated treatment >90 days after BC diagnosis. Compared to the surgery group, more women in the NAC group had stage III BC (34.8% vs 81.5%). Living further away from a hospital and having hormone receptor positive (vs negative) BC was associated with longer TTI (8 additional days per 100 km, P = .003 and 8 additional days, P = .01, respectively), while Ki67 proliferation index >20 and upfront surgery (vs NAC) was associated with shorter TTI (12 and 9 days earlier; P = .0001 and.007, respectively). Treatment initiation also differed among treating hospitals (P < .0001). Additional 30-day treatment delays were associated with worse survival in the surgery group (HR 1.11 [95%CI 1.003-1.22]), but not in the NAC group. CONCLUSIONS: Delays in BC treatment initiation are common in SA public hospitals and are associated with worse survival among women treated with upfront surgery.

Degree of food processing and breast cancer risk in black urban women from Soweto, South African: the South African Breast Cancer study.

This study aimed to investigate the association between consumption of ultra-processed foods, whole foods and breast cancer risk in black women from Soweto, South Africa. A population-based case (n 396)-control (n 396) study matched on age and residence, using data from the South African Breast Cancer study. Dietary intake was assessed using a validated quantified FFQ. Food items were categorised using the NOVA system ((1) unprocessed/minimally processed foods, (2) culinary ingredients, (3) processed foods and (4) ultra-processed foods). Conditional logistic regression models were used to estimate OR and 95 % CI of dietary contributions from each NOVA food group (as a percentage of total energy intake (EI)) and adjusting for potential confounders. Considering contributions to total EI per day, ultra-processed food consumption contributed to 44·8 % in cases and 47·9 % in controls, while unprocessed/minimally processed foods contributed to 38·8 % in cases and 35·2 % in controls. Unprocessed/minimally processed food consumption showed an inverse association with breast cancer risk overall (OR = 0·52, 95 % CI 0·35, 0·78), as well as in pre- and postmenopausal women separately (OR = 0·52, 95 % CI 0·27, 0·95 and OR = 0·55, 95 % CI 0·35, 0·89, respectively) and in women with progesterone positive breast cancer (OR = 0·23, 95 % CI 0·06, 0·86). There was no heterogeneity in association with breast cancer when analyses were stratified according to BMI. No significant associations were observed for the consumption of other NOVA food groups. Intake of unprocessed/minimally processed foods may reduce the risk of developing breast cancer in black women from Soweto, South Africa.

Adherence to cancer prevention recommendations is associated with a lower breast cancer risk in black urban South African women.

Breast cancer prevention is of great importance to reduce high incidence in South Africa. This study aimed to investigate adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Cancer Prevention Recommendations and the association with breast cancer risk in black urban women from Soweto, South Africa. A total of 396 breast cancer cases and 396 population-based controls from the South African Breast Cancer study (SABC) matched on age and demographic settings were included. Validated questionnaires were used to collect dietary and epidemiological data. To assess adherence to these recommendations, an eight-point adherence score was developed, using tertiles among controls for scoring each recommendation (0, 0·5 and 1) with zero indicating the lowest adherence to the recommendations. OR and 95 % CI were estimated using multivariate logistic regression models to analyse associations between the WCRF/AICR score and breast cancer risk. Greater adherence (>4·5 v. <3·25) to the 2018 WCRF/AICR Cancer Prevention Recommendations was associated with a significant inverse association with breast cancer risk overall (OR = 0·54, 95 % CI 0·35, 0·91) and specifically in postmenopausal women (OR = 0·55, 95 % CI 0·34, 0·95), in cases with oestrogen positive and progesterone positive breast cancer subtypes (OR = 0·54, 95 % CI 0·39, 0·89 and OR = 0·68, 95 % CI 0·43, 0·89, respectively) and in obese women (OR = 0·52, 95 % CI 0·35, 0·81). No significant association with breast cancer risk was observed in premenopausal women. Greater adherence to the 2018 WCRF/AICR Cancer Prevention Recommendations may reduce breast cancer risk in this black urban population of Soweto. Adherence thereof should be encouraged and form a part of cost-effective breast cancer prevention guidelines.

Preexisting morbidity profile of women newly diagnosed with breast cancer in sub-Saharan Africa: African Breast Cancer-Disparities in Outcomes study.

The presence of preexisting morbidities poses a challenge to cancer patient care. There is little information on the profile and prevalence of multi-morbidities in breast cancer patients across middle income countries (MIC) to lower income countries (LIC) in sub-Saharan Africa (SSA). The African Breast Cancer-Disparities in Outcomes (ABC-DO) breast cancer cohort spans upper MICs South Africa and Namibia, lower MICs Zambia and Nigeria and LIC Uganda. At cancer diagnosis, seven morbidities were assessed: obesity, hypertension, diabetes, asthma/chronic obstructive pulmonary disease, heart disease, tuberculosis and HIV. Logistic regression models were used to assess determinants of morbidities and the influence of morbidities on advanced stage (stage III/IV) breast cancer diagnosis. Among 2189 women, morbidity prevalence was the highest for obesity (35%, country-specific range 15-57%), hypertension (32%, 15-51%) and HIV (16%, 2-26%) then for diabetes (7%, 4%-10%), asthma (4%, 2%-10%), tuberculosis (4%, 0%-8%) and heart disease (3%, 1%-7%). Obesity and hypertension were more common in upper MICs and in higher socioeconomic groups. Overall, 27% of women had at least two preexisting morbidities. Older women were more likely to have obesity (odds ratio: 1.09 per 10 years, 95% CI 1.01-1.18), hypertension (1.98, 1.81-2.17), diabetes (1.51, 1.32-1.74) and heart disease (1.69, 1.37-2.09) and were less likely to be HIV positive (0.64, 0.58-0.71). Multi-morbidity was not associated with stage at diagnosis, with the exception of earlier stage in obese and hypertensive women. Breast cancer patients in higher income countries and higher social groups in SSA face the additional burden of preexisting non-communicable diseases, particularly obesity and hypertension, exacerbated by HIV in Southern/Eastern Africa.

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.

Reproductive factors and risk of breast cancer in black South African women.

PURPOSE: Breast cancer (BC) is increasing in black South African women, but few studies have investigated its risk factors. METHODS: We conducted an analysis of reproductive factors and BC risk in the South African Breast Cancer (SABC) study-a population-based case-control study of black South African women from Soweto that included 399 cases and 399 matched controls. Information on lifestyle and reproductive history was obtained by interviews. Conditional logistic regression was used to determine the association of reproductive factors with BC, adjusting for potential confounding factors. RESULTS: Seventy-five percent of all BC cases were ER+, 66% PR+, 30% HER2+, and 16% TN. None of the reproductive variables were associated with BC overall or by subtype in the overall population, nor in pre- (n = 135 cases) or in post-menopausal women separately. In HIV-negative pre-menopausal women (n = 97 cases), later age at first pregnancy and longer time between menarche and first full-time pregnancy were inversely related to BC risk (OR 0.89 (95% CI 0.82-0.97; and 0.93 95% CI 0.86-1.01, respectively). CONCLUSION: In this population of black South African women, reproductive factors were not associated with BC risk.

Adherence to the South African food based dietary guidelines may reduce breast cancer risk in black South African women: the South African Breast Cancer (SABC) study.

OBJECTIVE: To determine the level of adherence and to assess the association between higher adherence to the South African food based dietary guidelines (SAFBDG) and breast cancer risk. DESIGN: Population-based, case-control study (the South African Breast Cancer study) matched on age and demographic settings. Validated questionnaires were used to collect dietary and epidemiological data. To assess adherence to the SAFBDG, a nine-point adherence score (out of eleven guidelines) was developed, using suggested adherence cut-points for scoring each recommendation (0 and 1). When the association between higher adherence to the SAFBDG and breast cancer risk was assessed, data-driven tertiles among controls were used as cut-points for scoring each recommendation (0, 0·5 and 1). OR and 95 % CI were estimated using multivariate logistic regression models. SETTING: Soweto, South Africa. PARTICIPANTS: Black urban women, 396 breast cancer cases and 396 controls. RESULTS: After adjusting for potential confounders, higher adherence (>5·0) to the SAFBDG v. lower adherence (<3·5) was statistically significantly inversely associated with breast cancer risk overall (OR = 0·56, 95 % CI 0·38, 0·85), among postmenopausal women (OR = 0·64, 95 % CI 0·40, 0·97) as well as for oestrogen-positive breast cancers (OR = 0·51, 95 % CI 0·32, 0·89). Only 32·3 % of cases and 39·1 % of controls adhered to at least half (a score >4·5) of the SAFBDG. CONCLUSIONS: Higher adherence to the SAFBDG may reduce breast cancer risk in this population. The concerning low levels of adherence to the SAFBDG emphasise the need for education campaigns and to create healthy food environments in South Africa to increase adherence to the SAFBDG.

The multimorbidity profile of South African women newly diagnosed with breast cancer.

Multimorbidity in women with breast cancer may delay presentation, affect treatment decisions and outcomes. We described the multimorbidity profile of women with breast cancer, its determinants, associations with stage at diagnosis and treatments received. We collected self-reported data on five chronic conditions (hypertension, diabetes, cerebrovascular diseases, asthma/chronic obstructive pulmonary disease, tuberculosis), determined obesity using body mass index (BMI) and tested HIV status, in women newly diagnosed with breast cancer between January 2016 and April 2018 in five public hospitals in South Africa. We identified determinants of ≥2 of the seven above-mentioned conditions (defined as multimorbidity), multimorbidity itself with stage at diagnosis (advanced [III-IV] vs. early [0-II]) and multimorbidity with treatment modalities received. Among 2,281 women, 1,001 (44%) presented with multimorbidity. Obesity (52.8%), hypertension (41.3%), HIV (22.0%) and diabetes (13.7%) were the chronic conditions that occurred most frequently. Multimorbidity was more common with older age (OR = 1.02; 95% CI 1.01-1.03) and higher household socioeconomic status (HSES) (OR = 1.06; 95% CI 1.00-1.13). Multimorbidity was not associated with advanced-stage breast cancer at diagnosis, but for self-reported hypertension there was less likelihood of being diagnosed with advanced-stage disease in the adjusted model (OR 0.80; 95% CI 0.64-0.98). Multimorbidity was associated with first treatment received in those with early-stage disease, p = 0.003. The prevalence of multimorbidity is high among patients with breast cancer. Our findings suggest that multimorbidity had a significant impact on treatment received in those with early-stage disease. There is need to understand the impact of multimorbidity on breast cancer outcomes.

A comparison of complete pathologic response rates following neoadjuvant chemotherapy among South African breast cancer patients with and without concurrent HIV infection.

PURPOSE: Among patients diagnosed with breast cancer (BC), women also living with HIV (WLWH) have worse survival than women without HIV. Chronic HIV infection may interfere with the effectiveness of BC treatment, contributing to this disparity. We attempted to determine the impact of HIV infection on response to neoadjuvant chemotherapy (NACT) among South African women with BC. METHODS: We evaluated women from the South African Breast Cancer and HIV Outcomes cohort study who had stage I-III disease, initiated NACT, underwent definitive breast surgery, and had available surgical pathology reports. We compared pathologic complete response (pCR) rates among women with and without HIV infection, using multivariable logistic regression to control for differences in tumor characteristics. We also evaluated the impact of HIV infection on pCR within subgroups based on patient and tumor factors. RESULTS: Of 715 women, the 173 (24.2%) WLWH were less likely to achieve pCR than women without HIV (8.7% vs 16.4%, [odds ratio (OR) 0.48, 95% confidence interval (95% CI) 0.27-0.86]). WLWH continued to have lower likelihood of achieving pCR on multivariable analysis (OR 0.52, 95% CI 0.28-0.98). A similar pattern was seen within subgroups, although HIV infection appeared to affect pCR more in ER/PR-positive BC (OR 0.24, 95% CI 0.08-0.71) than in ER/PR-negative BC (OR 0.94, 95% CI 0.39-2.29). CONCLUSION: WLWH were less like to achieve pCR following NACT for BC than women without HIV. This reduced response to systemic therapy may contribute to the poorer BC outcomes seen in WLWH.

Neoadjuvant Chemotherapy Use for Nonmetastatic Breast Cancer at Five Public South African Hospitals and Impact on Time to Initial Cancer Therapy.

BACKGROUND: In the U.S., neoadjuvant chemotherapy (NAC) for nonmetastatic breast cancer (BC) is used with extensive disease and aggressive molecular subtypes. Little is known about the influence of demographic characteristics, clinical factors, and resource constraints on NAC use in Africa. MATERIALS AND METHODS: We studied NAC use in a cohort of women with stage I-III BC enrolled in the South African Breast Cancer and HIV Outcomes study at five hospitals. We analyzed associations between NAC receipt and sociodemographic and clinical factors, and we developed Cox regression models for predictors of time to first treatment with NAC versus surgery. RESULTS: Of 810 patients, 505 (62.3%) received NAC. Multivariate analysis found associations between NAC use and black race (odds ratio [OR] 0.49; 95% confidence limit [CI], 0.25-0.96), younger age (OR 0.95; 95% CI, 0.92-0.97 for each year), T-stage (T4 versus T1: OR 136.29; 95% CI, 41.80-444.44), N-stage (N2 versus N0: OR 35.64; 95% CI, 16.56-76.73), and subtype (triple-negative versus luminal A: OR 5.16; 95% CI, 1.88-14.12). Sites differed in NAC use (Site D versus Site A: OR 5.73; 95% CI, 2.72-12.08; Site B versus Site A: OR 0.37; 95% CI, 0.16-0.86) and time to first treatment: Site A, 50 days to NAC versus 30 days to primary surgery (hazard ratio [HR] 1.84; 95% CI, 1.25-2.71); Site D, 101 days to NAC versus 126 days to primary surgery (HR 0.49; 95% CI, 0.27-0.89). CONCLUSION: NAC use for BC at these South African hospitals was associated with both tumor characteristics and heterogenous resource constraints. IMPLICATIONS FOR PRACTICE: Using data from a large breast cancer cohort treated in South Africa's public healthcare system, the authors looked at determinants of neoadjuvant chemotherapy use and time to initiate treatment. It was found that neoadjuvant chemotherapy was associated with increasing tumor burden and aggressive molecular subtypes, demonstrating clinically appropriate care in a lower resource setting. Results of this study also showed that time to treatment differences between chemotherapy and surgery varied by hospital, suggesting that differences in resource limitations were influencing clinical decision making. Practice guidelines and care quality metrics designed for low- and middle-income countries should accommodate heterogeneity of available resources.

Dietary intake and breast cancer risk in black South African women: the South African Breast Cancer study.

Incidence rates of breast cancer (BC) are increasing in South Africa. The aim of this study was to investigate the association between dietary intake and BC risk in black South African women. The study population included 396 BC cases and 396 population-based controls matched on age and residence, participating in the South African Breast Cancer study. Diet was assessed using a validated quantified FFQ from which twelve energy-adjusted food groups were formed and analysed. OR were estimated using conditional logistic regressions, adjusted for confounding factors, comparing highest v. lowest median intake. Fresh fruit consumption showed an inverse association with BC risk (OR=0·3, 95 % CI 0·12, 0·80) in premenopausal women, whilst red and organ meat consumption showed an overall inverse association with BC risk (OR=0·6, 95 % CI 0·49, 0·94 and OR=0·6, 95 % CI 0·47, 0·91). Savoury food consumption (sauces, soups and snacks) were positively associated with BC risk in postmenopausal women (OR=2·1, 95 % CI 1·15, 4·07). Oestrogen receptor-positive stratification showed an inverse association with BC risk and consumption of nuts and seeds (OR=0·2, 95 % CI 0·58, 0·86). Based on these results, it is recommended that black South African women follow a diet with more fruit and vegetables together with a decreased consumption of less energy-dense, micronutrient-poor foods such as savoury foods. More research is necessary to investigate the association between BC risk and red and organ meat consumption. Affordable and practical methods regarding these recommendations should be implemented within health intervention strategies.

Drivers of advanced stage at breast cancer diagnosis in the multicountry African breast cancer - disparities in outcomes (ABC-DO) study.

Breast cancer (BC) survival rates in sub-Saharan Africa (SSA) are low in part due to advanced stage at diagnosis. As one component of a study of the entire journey of SSA women with BC, we aimed to identify shared and setting-specific drivers of advanced stage BC. Women newly diagnosed in the multicountry African Breast Cancer-Disparities in Outcomes (ABC-DO) study completed a baseline interview and their stage information was extracted from medical records. Ordinal logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for advanced stage (I, II, III, IV) in relation to individual woman-level, referral and biological factors. A total of 1795 women were included from Nigeria, Uganda, Zambia, and the multiracial populations of Namibia and South Africa, 1091 of whom (61%) were stage III/IV. Stage was lower in women with greater BC knowledge (OR 0.77 (95% CI: 0.70, 0.85) per point on a 6 point scale). More advanced stage was associated with being black (4.00 (2.79, 5.74)), having attended