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.

The South African breast cancer and HIV outcomes study: Profiling the cancer centres and cohort characteristics, diagnostic pathways, and treatment approaches

The South African Breast Cancer and HIV Outcomes prospective cohort (SABCHO) study was established to investigate survival determinants among HIV-positive and HIV-negative SA women with breast cancer. This paper describes common and unique characteristics of the cancer centres and their participants, examining disparities in pathways to diagnosis, treatment resources and approaches adopted to mitigate resource constraints. The Johannesburg (Jhb), Soweto (Sow), and Durban (Dbn) sites treat mainly urban, relatively better educated and more socioeconomically advantaged patients whereas the Pietermaritzburg (Pmb) and Empangeni (Emp) sites treat predominantly rural, less educated and more impoverished communities The Sow, Jhb, and Emp sites had relatively younger patients (mean ages 54 ±14.5, 55±13.7 and 54±14.3 respectively), whereas patients at the Dbn and Pmb sites, with greater representation of Asian Indian women, were relatively older (mean age 57 ±13.9 and 58 ±14.6 respectively). HIV prevalence among the cohort was high, ranging from 15%-42%, (Cohort obesity (BMI ≥ 30 kg/m2) at 60%, self-reported hypertension (41%) and diabetes (13%). Direct referral of patients from primary care clinics to cancer centre occurred only at the Sow site which uniquely ran an open clinic and where early stage (I and II) proportions were highest at 48.5%. The other sites relied on indirect patient referral from regional hospitals where significant delays in diagnostics occurred and early-stage proportions were a low (15%- 37.3%). The Emp site referred patients for all treatments to the Dbn site located 200km away; the Sow site provided surgery and endocrine treatment services but referred patients to the Jhb site 30 Km away for chemo- and radiation therapy. The Jhb, Dbn and Pmb sites all provided complete oncology treatment services. All treatment centres followed international guidelines for their treatment approaches. Findings may inform policy interventions to address national and regional disparities in breast cancer care.

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.

Abstract P4-07-03: The impact of HIV on non-adherence for tamoxifen among women with breast cancer in South Africa

Introduction HIV-positive women with 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 women with stages I-III HR-positive breast cancer who were prescribed 20mg of adjuvant tamoxifen daily for ≥3 months during the study period. 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 < 60ng/mL after 3 months of prescribed daily tamoxifen use. We compared socio-demographic, lifestyle factors, 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 participants, 78 (21.1%) were HIV-positive and 291 (78.9%) 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 943.0ng/mL, with a median of 52.3ng/mL. In the full cohort, 208 women (56.4%) were non-adherent to tamoxifen; only 161 (43.6%) were adherent. Women < 40 years of age were less likely to adhere to tamoxifen than women >60 years (73.4% vs 52.6%, odds ratio (OR)=2.49, 95% confidence interval (CI)=1.26-4.94); likewise, HIV-positive women (70.5% vs 52.6%, OR=2.16, 95% CI=1.26-3.70) were less likely to adhere than HIV-negative women. In an adjusted model, only HIV was associated with non-adherence; HIV-positive women had twice the odds of non-adherence to tamoxifen, compared to HIV-negative women (OR=2.40, 95% CI=1.11-5.20). Conclusion Non-adherence to tamoxifen may limit the overall survival of women with HR-positive breast cancer; in our study, especially in HIV-positive women.

Citation Format: Oluwatosin A Ayeni, Shingirai Chiwambutsa, Wenlong Carl Chen, Nyasha N. Kapungu, Comfort Kanji, Roslyn Thelingwani, Nivashni Murugan, Rophiwa Mathiba, Boitumelo Phakathi, Sarah Nietz, Duvern Ramiah, Daniel S. O’Neil, Judith S. Jacobson, Paul Ruff, Herbert Cubasch, Tobias Chirwa, Maureen Joffe, Collen Masimirembwa, Alfred I. Neugut. The impact of HIV on non-adherence for tamoxifen among women with breast cancer in South Africa [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-07-03.

Drivers of disparities in stage at diagnosis among women with breast cancer: South African breast cancers and HIV outcomes cohort

OBJECTIVE

In low- and middle-income countries (LMICs), advanced-stage diagnosis of breast cancer (BC) is common, and this contributes to poor survival. Understanding the determinants of the stage at diagnosis will aid in designing interventions to downstage disease and improve survival from BC in LMICs.

METHODS

Within the South African Breast Cancers and HIV Outcomes (SABCHO) cohort, we examined factors affecting the stage at diagnosis of histologically confirmed invasive breast cancer at five tertiary hospitals in South Africa (SA). The stage was assessed clinically. To examine the associations of the modifiable health system, socio-economic/household and non-modifiable individual factors, hierarchical multivariable logistic regression with odds of late-stage at diagnosis (stage III-IV), was used.

RESULTS

The majority (59%) of the included 3497 women were diagnosed with late-stage BC disease. The effect of health system-level factors on late-stage BC diagnosis was consistent and significant even when adjusted for both socio-economic- and individual-level factors. Women diagnosed in a tertiary hospital that predominantly serves a rural population were 3 times (OR = 2.89 (95% CI: 1.40-5.97) as likely to be associated with late-stage BC diagnosis when compared to those diagnosed at a hospital that predominantly serves an urban population. Taking more than 3 months from identifying the BC problem to the first health system entry (OR = 1.66 (95% CI: 1.38-2.00)), and having luminal B (OR = 1.49 (95% CI: 1.19-1.87)) or HER2-enriched (OR = 1.64 (95% CI: 1.16-2.32)) molecular subtype as compared to luminal A, were associated with a late-stage diagnosis. Whilst having a higher socio-economic level (a wealth index of 5) reduced the probability of late-stage BC at diagnosis, (OR = 0.64 (95% CI: 0.47-0.85)).

CONCLUSION

Advanced-stage diagnosis of BC among women in SA who access health services through the public health system was associated with both modifiable health system-level factors and non-modifiable individual-level factors. These may be considered as elements in interventions to reduce the time to diagnosis of breast cancer in women.

Localization Techniques for Non-Palpable Breast Lesions: Current Status, Knowledge Gaps, and Rationale for the MELODY Study (EUBREAST-4/iBRA-NET, NCT 05559411)

BACKGROUND

Surgical excision of a non-palpable breast lesion requires a localization step. Among available techniques, wire-guided localization (WGL) is most commonly used. Other techniques (radioactive, magnetic, radar or radiofrequency-based, and intraoperative ultrasound) have been developed in the last two decades with the aim of improving outcomes and logistics.

METHODS

We performed a systematic review on localization techniques for non-palpable breast cancer.

RESULTS

For most techniques, oncological outcomes such as lesion identification and clear margin rate seem either comparable with or better than for WGL, but evidence is limited to small cohort studies for some of the devices. Intraoperative ultrasound is associated with significantly higher negative margin rates in meta-analyses of randomized clinical trials (RCTs). Radioactive techniques were studied in several RCTs and are non-inferior to WGL. Smaller studies show higher patient preference towards wire-free localization, but little is known about surgeons' and radiologists' attitudes towards these techniques.

CONCLUSIONS

Large studies with an additional focus on patient, surgeon, and radiologist preference are necessary. This review aims to present the rationale for the MELODY (NCT05559411) study and to enable standardization of outcome measures for future studies.

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.

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.

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.

Isolated ductal carcinoma in situ in patients presenting to two breast units in Johannesburg

BACKGROUND

Ductal carcinoma in situ (DCIS) represents approximately 20% of all new breast cancers in countries with population-based mammography screening. South Africa is an upper middle-income country with no such screening programmes in place, and the proportion of isolated DCIS appears much lower than this. Most patients present with symptomatic disease and high-risk features. There are numerous controversies regarding the diagnosis and optimal management strategy for this premalignant condition, and the issue of overtreatment is much debated. Our study aimed to determine the proportion of patients presenting with isolated DCIS, to describe the clinical presentation and to describe the treatment provided.

METHODS

This is a retrospective cohort study of patients with histologically confirmed isolated DCIS at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital from July 2015 to March 2018. Records were collected from the existing clinical databases in both breast units and from the South African National Health Laboratory System.

RESULTS

Out of 1 813 patients diagnosed and managed with breast malignancies in this period, 58 (3.1%) patients were identified with isolated DCIS. Forty-three (74.1%) of these patients were symptomatic. Thirty-four (58.6%) patients had a primary mastectomy, and 12 (20.6%) had breast-conserving surgery.

CONCLUSION

The diagnosis of isolated DCIS is rare in our setting, and the majority of patients present with more advanced, symptomatic disease that is not deemed suitable for breast-conserving surgery. The short-term follow-up of our patients has shown a low rate of recurrence and mortality thus far. However, further long-term follow-up is needed.

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.

Isolated ductal carcinoma in situ in patients presenting to two breast units in Johannesburg

BACKGROUND: Ductal carcinoma in situ (DCIS) represents approximately 20% of all new breast cancers in countries with population-based mammography screening. South Africa is an upper middle-income country with no such screening programmes in place, and the proportion of isolated DCIS appears much lower than this. Most patients present with symptomatic disease and high-risk features. There are numerous controversies regarding the diagnosis and optimal management strategy for this premalignant condition, and the issue of overtreatment is much debated. Our study aimed to determine the proportion of patients presenting with isolated DCIS, to describe the clinical presentation and to describe the treatment provided. METHODS: This is a retrospective cohort study of patients with histologically confirmed isolated DCIS at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital from July 2015 to March 2018. Records were collected from the existing clinical databases in both breast units and from the South African National Health Laboratory System. RESULTS: Out of 1 813 patients diagnosed and managed with breast malignancies in this period, 58 (3.1%) patients were identified with isolated DCIS. Forty-three (74.1%) of these patients were symptomatic. Thirty-four (58.6%) patients had a primary mastectomy, and 12 (20.6%) had breast-conserving surgery. CONCLUSION: The diagnosis of isolated DCIS is rare in our setting, and the majority of patients present with more advanced, symptomatic disease that is not deemed suitable for breast-conserving surgery. The short-term follow-up of our patients has shown a low rate of recurrence and mortality thus far. However, further long-term follow-up is needed.

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.

Quality of Histopathological Reporting in Breast Cancer: Results From Four South African Breast Units

PURPOSE

High-quality histopathology reporting forms the basis for treatment decisions. The quality indicator for pathology reports from the European Society of Breast Cancer Specialists was applied to a cohort from four South African breast units.

METHODS

The study included 1,850 patients with invasive breast cancer and evaluated 1,850 core biopsies and 1,158 surgical specimen reports with cross-center comparisons. A core biopsy report required histologic type; tumor grade; and estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) status, with a confirmatory test for equivocal HER2 results. Ki-67 was regarded as optional. Pathologic stage, tumor size, lymphovascular invasion, and distance to nearest invasive margin were mandatory for surgical specimens. Specimen turnaround time (TAT) was added as a locally relevant indicator.

RESULTS

Seventy-five percent of core biopsy and 74.3% of surgical specimen reports were complete but showed large variability across study sites. The most common reason for an incomplete core biopsy report was missing tumor grade (17.9%). Half of the equivocal HER2 results lacked confirmatory testing (50.6%). Ki-67 was reported in 89.3%. For surgical specimens, the closest surgical margin was reported in 78.1% and lymphovascular invasion in 84.8% of patients. Mean TAT was 11.9 days (standard deviation [SD], 10.8 days) for core biopsies and 16.1 days (SD, 11.3) for surgical specimens.

CONCLUSION

Histopathology reporting is at a high level but can be improved, especially for tumor grade, HER2, and Ki-67, as is reporting of margins and lymphovascular invasion. A South African pathology consensus will reduce variability among laboratories. Routine use of standardized data sheets with synoptic reports and ongoing audits will improve completeness of reports over time.

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

6559

Background: Advanced stage at breast cancer (BC) diagnosis is common in sub-Saharan Africa. In public hospitals across South Africa (SA), 10-15% of women present with metastatic BC, compared to <5% in the U.S., and 20% of new BCs are diagnosed in women living with HIV (WLWH). We evaluated the impact of HIV on overall survival (OS) among women with stage IV BC, which is associated with a poor prognosis in SA. 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. Baseline characteristics were compared by HIV status and multivariate Cox regression models were used to estimate the effect of HIV on 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 BC (32.7% vs. 22.6%, p=0.016). HER2 tumor status did not differ by HIV status (25.3% HER2 positive overall), and Ki67 index was not increased among WLWH (57.1% Ki67 > 20 overall). Receipt of systemic anti-cancer therapy did not differ by HIV status (80.9% treated overall) and most women were treated with anthracycline (55.5%). HIV status was not associated with OS (Hazard Ratio (HR)=1.13, 95% confidence interval (CI)=0.89-1.44) (Table). In an exploratory subgroup analysis, WLWH and hormone receptor-negative BC had shorter OS compared to HIV-negative women (1-year OS: 27.1% vs. 48.8%, p=0.003; HR=1.94, 95% CI=1.27-2.94), which was not observed for hormone receptor-positive BC. Results were unchanged when analysis was restricted to black women only. Conclusions: HIV status was not associated with worse OS in women with stage IV BC in SA and cannot account for the poor survival in our cohort. Subgroup analysis revealed that WLWH with hormone receptor-negative BC had worse OS; this differential effect of HIV on BC survival by hormone receptor status is a novel finding that warrants further investigation.[Table: see text]

Quality indicators for the diagnosis and surgical management of breast cancer in South Africa

INTRODUCTION

Quality indicators (QIs) for breast cancer care have been developed and applied in high-income countries and contributed to improved quality of care and patient outcomes over time.

MATERIALS AND METHODS

A modified Delphi process was used to derive expert consensus. Potential QIs were rated by a panel of 17 breast cancer experts from various subspecialties and across South African provinces. Each QI was rated according to importance to measure, scientific acceptability and feasibility. Scoring ranged from 1 (no agreement) to 5 (strong agreement). Inclusion thresholds were set a priori at mean ratings ≥4 with a coefficient variation of ≥25%. Levels of evidence were determined for each indicator.

RESULTS

The literature review identified 790 potential QIs. After categorisation and removal of duplicates, 52 remained for panel review. There was strong consensus for 47 which were merged to 30 QIs by exclusion of similar indicators and indicator grouping. The final set included eight QIs with level I or II evidence and two QIs with level III evidence which were deemed "mandatory" due to clinical priority and impact on care. The remaining QIs with lower-level evidence were grouped as eight "recommended" QIs (regarded as standard of care) and twelve "optional" QIs (not regarded as standard of care).

CONCLUSION

A regional set of QIs was developed to facilitate standardised treatment and auditing of surgical care for breast cancer patients in South Africa. Routine monitoring of the ten mandatory QIs, which were selected to have the most substantial impact on patient outcome, is proposed.

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.

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 prospective study of receptor profiles in breast cancer and the ipsilateral axillary lymph node metastases measured simultaneously in treatment naïve cases

BACKGROUND

The heterogeneity of receptor profiles in breast cancer is well known. The differing receptor profiles of primary breast cancer and nodal metastases have been investigated and found to range between 10-50% depending on the hormone receptor tested. A study comparing the hormone status of primary breast cancers and the synchronous ipsilateral involved sentinel lymph node has not been performed in a South African population.

METHOD

This is a prospective study where two specialist radiologists performed the simultaneous core needle biopsies of the primary breast cancer and the clinically positive axillary nodes. All receptor status analysis was conducted by one specialist histopathologist.

RESULTS

Of 141 patients who gave written informed consent for this study, 29 were excluded; 112 patients met the inclusion criteria. Anonymised demographics of age, clinical stage, HIV status and metastatic screening were recorded. The simultaneous biopsies and receptor measurements identified 10 patients with discordant receptor status in the positive axillary lymph nodes. In each case, the receptor profile of the axillary lymphatic metastases was more aggressive than that of the primary tumour. The luminal A subtype had a significantly greater risk of discordance than other subtypes (p = 0.02).

CONCLUSION

Core needle biopsy and receptor analysis should be considered on the positive axillary nodes in breast cancer patients. Adjuvant treatment should be targeted to the receptor profile of the lymph node metastases.

Breast Cancer Care Quality in South Africa's Public Health System: An Evaluation Using American Society of Clinical Oncology/National Quality Forum Measures

PURPOSE

The quality of breast cancer care in sub-Saharan Africa contributes to the region’s dismal breast cancer mortality. ASCO has issued quality measures focusing on delivery of adjuvant chemotherapy, radiotherapy, and endocrine therapy. We applied these measures in five South African public hospitals and analyzed factors associated with care concordance.

MATERIALS AND METHODS

Among 1,736 women with breast cancer who were enrolled in the South African Breast Cancer and HIV Outcomes study over 24 months, we evaluated care using ASCO’s three measures. We also evaluated adjuvant chemotherapy receipt in 957 women with an indication. We used logistic regression to estimate associations between measure-concordant care and patient factors.

RESULTS

Of 235 women with hormone receptor–negative cancer, 173 (74%) began adjuvant chemotherapy within 120 days from diagnosis. Of 194 patients who received breast-conserving surgery, 73 (37%) began radiotherapy within 365 days from diagnosis. Of 999 women with hormone receptor–positive cancer, 719 (72%) initiated endocrine therapy within 365 days from diagnosis. Chemotherapy and radiotherapy measure-concordant care were more common among women residing < 20 km from the hospital (odds ratio [OR], 1.79; 95% CI, 1.32 to 2.44 and OR, 3.17; 95% CI, 1.57 to 6.42). Endocrine therapy measure-concordant care was more common among English-speaking women (OR, 2.12; 95% CI, 1.12 to 4.02). Participating hospitals varied in care concordance. HIV infection did not affect care quality.

CONCLUSION

More timely delivery of chemotherapy, radiotherapy, and endocrine therapy is needed in South Africa, particularly for women living > 20 km from the hospital or not speaking English. Focused quality improvement efforts could support that goal.

Axillary lymph node dissection for patients with invasive breast cancer at Charlotte Maxeke and Chris Hani Baragwanath Academic Hospitals

BACKGROUND

The extent of axillary surgery correlates with its morbidity and sentinel lymph node biopsy (SLNB) has become the standard of care in clinically node-negative (cN0) patients.This study aims to evaluate the application of SLNB and axillary lymph node dissection (ALND) and the associated risk factors for node-negative ALND in our units.

METHODS

We included female patients with primary breast cancer who underwent axillary surgery in the breast units at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital from March 2013 to March 2015. Univariate and multivariable logistic regression models were used to determine factors associated with pathological node-negative (pN0) ALND.

RESULTS

505 patients were included and 344 patients were staged clinically node-positive (68.1%), 161 (31.9%) were assessed as clinically node-negative and deemed eligible for SLNB. Sensitivity of clinical nodal staging was 85.9% with a positive predictive value of 76.5%. The majority of patients (313, 61.9%) underwent primary surgery while 192 (38.1%) underwent surgery after NACT. We performed 118 SLNBs and 387 ALNDs of which 97 were pathologically node-negative. Risk was not increased after NACT (OR 1.06, p = 0.790). We identified a significant risk in patients with triple-negative and HER-2 enriched subtypes compared to hormone receptor-positive patients (OR 3.05, 95% CI: 1.6-5.7, p = 0.001 and OR 2.25, 95% CI: 1.1-4.8, p = 0.035).

CONCLUSION

The prevalence of pN0 ALND was 25.06%. In our cohort a significantly higher risk was found in hormone receptor-negative tumours. Preoperative nodal assessment needs to be optimised and include pathological confirmation. SLNB needs to be extended to patients after NACT despite resource-constraints.

Chromosomal radiosensitivity of triple negative breast cancer patients

Purpose: Based on clinical and molecular data, breast cancer is a heterogeneous disease. Breast cancers that have no expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) are defined as triple negative breast cancers (TNBCs); luminal cancers have different expressions of ER, PR and/or HER2. TNBCs are frequently linked with advanced disease, poor prognosis and occurrence in young African women, and about 15% of the cases are associated with germline BRCA1/2 mutations. Since radiotherapy is utilized as a principle treatment in the management of TNBC, we aimed to investigate the chromosomal instability and radiosensitivity of lymphocytes in TNBC patients compared to luminal breast cancer patients and healthy controls using the micronucleus (MN) assay. The effect of mutations in breast cancer susceptibility genes on chromosomal radiosensitivity was also evaluated.Methods: Chromosomal radiosensitivity was evaluated in the G0 (83 patients and 90 controls) and S/G2 (34 patients and 17 controls) phase of the cell cycle by exposing blood samples from all patients and controls to 2 and 4 Gy ionizing radiation (IR).Results: In the G0 MN assay, the combined cohort of all breast cancer, TNBC and luminal patients' exhibit significantly elevated spontaneous MN values compared to controls indicating chromosomal instability. Chromosomal radiosensitivity is also significantly elevated in the combined cohort of all breast cancer patients compared to controls. The TNBC patients, however, do not exhibit enhanced chromosomal radiosensitivity. Similarly, in the S/G2 phase, 76% of TNBC patients do not show enhanced chromosomal radiosensitivity compared to the controls. In both the G0 and S/G2 phase, luminal breast cancer patients demonstrate a shift toward chromosomal radiosensitivity compared to TNBC patients and controls.Conclusions: The observations of the MN assay suggest increased chromosomal instability and chromosomal radiosensitivity in South African breast cancer patients. However, in TNBC patients, the irradiated MN values are not elevated. Our results suggest that the healthy lymphocytes in TNBC patients could handle higher doses of IR.

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

PURPOSE

Breast cancer is the most common cancer in women and a leading cause of cancer-related mortality worldwide. South Africa has the largest global burden of HIV infection and the largest anti-retroviral treatment (ART) program. This study aimed to analyse the association of HIV and ART use with breast cancer clinico-pathological characteristics.

METHODS

Study participants were females, newly diagnosed from May 2015 through September 2017 with invasive breast cancer at two academic Surgical Breast Units in Johannesburg, South Africa at the Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital. We compared HIV-positive and HIV negative patients' demographic and clinical-pathological characteristics at the time of breast cancer diagnosis.

RESULTS

Of 1050 patients enrolled, 1016 (96.8%) had known HIV status, with 226 (22.2%) being HIV positive. HIV positive patients were younger (median (IQR) age 45 (40-52) years), than HIV-negative patients (median (IQR) age 57 (46-67)) (p < 0.001). HIV positive patients were more likely to be diagnosed with late stage breast cancer (p = 0.01). However, HIV positive patients receiving ART at the time of breast cancer diagnosis were less likely to present with metastatic disease than those not on ART (p = 0.05).

CONCLUSION

HIV-positive patients present with breast cancer at a younger age and later stage disease than HIV-negative patients. Neither the duration of HIV infection nor ART use was associated with clinico-pathological characteristics of breast cancer.

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

In sub‐Saharan Africa, clinical decisions can be affected by resource constraints. This article analyzes the clinical and sociodemographic factors associated with receiving neoadjuvant chemotherapy among patients from a previously existing cohort: women enrolled in the prospective South African Breast Cancer and HIV Outcomes study.

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.

South African Breast Cancer and HIV Outcomes Study: Methods and Baseline Assessment

Purpose

In low- and middle-income, HIV-endemic regions of sub-Saharan Africa, morbidity and mortality from the common epithelial cancers of the developed world are rising. Even among HIV-infected individuals, access to antiretroviral therapy has enhanced life expectancy, shifting the distribution of cancer diagnoses toward non–AIDS-defining malignancies, including breast cancer. Building on our prior research, we recently initiated the South African Breast Cancer and HIV Outcomes study.

Methods

We will recruit a cohort of 3,000 women newly diagnosed with breast cancer at hospitals in high (average, 20%) HIV prevalence areas, in Johannesburg, Durban, Pietermaritzburg, and Empangeni. At baseline, we will collect information on demographic, behavioral, clinical, and other factors related to access to health care. Every 3 months in year 1 and every 6 months thereafter, we will collect interview and chart data on treatment, symptoms, cancer progression, comorbidities, and other factors.

We will compare survival rates of HIV-infected and uninfected women with newly diagnosed breast cancer and their likelihood of receiving suboptimal anticancer therapy. We will identify determinants of suboptimal therapy and context-specific modifiable factors that future interventions can target to improve outcomes. We will explore molecular mechanisms underlying potentially aggressive breast cancer in both HIV-infected and uninfected patients, as well as the roles of pathogens, states of immune activation, and inflammation in disease progression.

Conclusion

Our goals are to contribute to development of evidence-based guidelines for the management of breast cancer in HIV-positive women and to improve outcomes for all patients with breast cancer in resource-constrained settings.

BRCA1, BRCA2 and PALB2 mutations and CHEK2 c.1100delC in different South African ethnic groups diagnosed with premenopausal and/or triple negative breast cancer

Background

Current knowledge of the aetiology of hereditary breast cancer in the four main South African population groups (black, coloured, Indian and white) is limited. Risk assessments in the black, coloured and Indian population groups are challenging because of restricted information regarding the underlying genetic contributions to inherited breast cancer in these populations. We focused this study on premenopausal patients (diagnosed with breast cancer before the age of 50; n = 78) and triple negative breast cancer (TNBC) patients (n = 30) from the four South African ethnic groups. The aim of this study was to determine the frequency and spectrum of germline mutations in BRCA1, BRCA2 and PALB2 and to evaluate the presence of the CHEK2 c.1100delC allele in these patients.

Methods

In total, 108 South African breast cancer patients underwent mutation screening using a Next-Generation Sequencing (NGS) approach in combination with Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large rearrangements in BRCA1 and BRCA2.

Results

In 13 (12 %) patients a deleterious mutation in BRCA1/2 was detected, three of which were novel mutations in black patients. None of the study participants was found to have an unequivocal pathogenic mutation in PALB2. Two (white) patients tested positive for the CHEK2 c.1100delC mutation, however, one of these also carried a deleterious BRCA2 mutation. Additionally, six variants of unknown clinical significance were identified (4 in BRCA2, 2 in PALB2), all in black patients. Within the group of TNBC patients, a higher mutation frequency was obtained (23.3 %; 7/30) than in the group of patients diagnosed before the age of 50 (7.7 %; 6/78).

Conclusion

This study highlights the importance of evaluating germline mutations in major breast cancer genes in all of the South African population groups. This NGS study shows that mutation analysis is warranted in South African patients with triple negative and/or in premenopausal breast cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1913-6) contains supplementary material, which is available to authorized users.

Disarrangement of fiber tracts and decline of neuronal density correlate in glioma patients--a combined diffusion tensor imaging and 1H-MR spectroscopy study

BACKGROUND AND PURPOSE

Diffusion tensor imaging (DTI) and MR spectroscopy are noninvasive, quantitative tools for the preoperative assessment of gliomas with which the quantitative parameter fractional anisotropy (FA) and the concentration of neurometabolites N-acetylaspartate (NAA), choline (Cho), creatine (Cr) of the brain can be determined. Measurements of FA and NAA reflect the integrity of fiber tracts and the presence of neurons, respectively. This investigation examines changes of FA and NAA and compares these different aspects in architecture of gliomas after spatial coregistration.

METHODS

DTI and chemical shift (1)H-MR spectroscopy was performed in 34 healthy volunteers and 69 patients with histologically confirmed (n = 48) or morphologically suspected (n = 21) non-necrotic brain glioma. Volumes of interest (VOIs) were placed in the tumor center (TC), the tumor border (TB), the normal-appearing white matter adjacent to the tumors (TNWM), and in the white matter of the contralateral hemisphere (NWMC). Median FA values and NAA/Cr and NAA/Cho ratios were calculated in the patients' VOIs and the gray and white matter of the volunteers. Correlations of FA values and NAA ratios were calculated.

RESULTS

Continuous changes of FA and NAA from the tumor center to the periphery (the adjacent white matter and the contra-lateral hemisphere, respectively) were observed, where median values were: TC: 0.73 +/- 0.45, 0.47 +/- 0.58, 0.17 +/- 0.15 (NAA/Cr, NAA/Cho, FA); TB: 1.06 +/- 0.53, 1.00 +/- 0.15, 0.23 +/- 0.08; TNWM: 1.42 +/- 2.48, 1.21 +/- 0.95, 0.34 +/- 0.09; and NWMC: 1.63 +/- 0.72, 1.56 +/- 1.34, 0.38 +/- 0.08. Correlation of median FA values and NAA ratios in the cumulative group of patients was high (r = 0.99 [NAA/Cr], 0.95 [NAA/ Cho] at P < .01). Correlation between the individual NAA ratios and the FA values was moderate (r = 0.53 [NAA/Cr], 0.51 [NAA/Cho] at P < .01).

CONCLUSION

In gliomas, the degree of tissue organization decreases continuously from the surrounding tissue toward the center of the tumor accompanied by a concordant decrease of NAA. This uniform behavior of FA and NAA reflects a decreasing integrity of both neuronal structures and fibers.