Use of Recommended Neurodiagnostic Evaluation Among Patients With Drug-Resistant Epilepsy

Importance

Interdisciplinary practice parameters recommend that patients with drug-resistant epilepsy (DRE) undergo comprehensive neurodiagnostic evaluation, including presurgical assessment. Reporting from specialized centers suggests long delays to referral and underuse of surgery; however, longitudinal data are limited to characterize neurodiagnostic evaluation among patients with DRE in more diverse US settings and populations.

Objective

To examine the rate and factors associated with neurodiagnostic studies and comprehensive evaluation among patients with DRE within 3 US cohorts.

Design, Setting, and Participants

A retrospective cross-sectional study was conducted using the Observational Medical Outcomes Partnership Common Data Model including US multistate Medicaid data, commercial claims data, and Columbia University Medical Center (CUMC) electronic health record data. Patients meeting a validated computable phenotype algorithm for DRE between January 1, 2015, and April 1, 2020, were included. No eligible participants were excluded.

Exposure

Demographic and clinical variables were queried.

Main Outcomes and Measures

The proportion of patients receiving a composite proxy for comprehensive neurodiagnostic evaluation, including (1) magnetic resonance or other advanced brain imaging, (2) video electroencephalography, and (3) neuropsychological evaluation within 2 years of meeting the inclusion criteria.

Results

A total of 33 542 patients with DRE were included in the Medicaid cohort, 22 496 in the commercial insurance cohort, and 2741 in the CUMC database. A total of 31 516 patients (53.6%) were women. The proportion of patients meeting the comprehensive evaluation main outcome in the Medicaid cohort was 4.5% (n = 1520); in the commercial insurance cohort, 8.0% (n = 1796); and in the CUMC cohort, 14.3% (n = 393). Video electroencephalography (24.9% Medicaid, 28.4% commercial, 63.2% CUMC) and magnetic resonance imaging of the brain (35.6% Medicaid, 43.4% commercial, 52.6% CUMC) were performed more regularly than neuropsychological evaluation (13.0% Medicaid, 16.6% commercial, 19.2% CUMC) or advanced imaging (3.2% Medicaid, 5.4% commercial, 13.1% CUMC). Factors independently associated with greater odds of evaluation across all 3 data sets included the number of inpatient and outpatient nonemergency epilepsy visits and focal rather than generalized epilepsy.

Conclusions and Relevance

The findings of this study suggest there is a gap in the use of diagnostic studies to evaluate patients with DRE. Care setting, insurance type, frequency of nonemergency visits, and epilepsy type are all associated with evaluation. A common data model can be used to measure adherence with best practices across a variety of observational data sources.

Site-specific patterns of early-stage cancer diagnosis during the COVID-19 pandemic

The COVID-19 pandemic caused widespread disruptions in cancer care. We hypothesized that the greatest disruptions in diagnosis occurred in screen-detected cancers. We identified patients (≥18 years of age) with newly diagnosed cancer from 2019 to 2020 in the US National Cancer Database and calculated the change in proportion of early-stage to late-stage cancers using a weighted linear regression. Disruptions in early-stage diagnosis were greater than in late-stage diagnosis (17% vs 12.5%). Melanoma demonstrated the greatest relative decrease in early-stage vs late-stage diagnosis (22.9% vs 9.2%), whereas the decrease was similar for pancreatic cancer. Compared with breast cancer, cervical, melanoma, prostate, colorectal, and lung cancers showed the greatest disruptions in early-stage diagnosis. Uninsured patients experienced greater disruptions than privately insured patients. Disruptions in cancer diagnosis in 2020 had a larger impact on early-stage disease, particularly screen-detected cancers. Our study supports emerging evidence that primary care visits may play a critical role in early melanoma detection.

The Statistical Significance Revolution

Statistical significance has long relied on the criterion of p < 0.05. While it has generally functioned well, it has engendered some negative practices to circumvent this threshold and been criticized as too inflexible. We concur with the statisticians and methodologists who are currently arguing for more flexibility to the p-value and more reliance on the 95% confidence interval; this is likely to change future practice in data analysis and interpretation in oncology.

Prognosis and risk of suicide after cancer diagnosis

INTRODUCTION

Suicide rates are elevated after cancer diagnosis. Existential distress caused by awareness of one's impending death is well-described in patients with cancer. The authors hypothesized that suicide risk is associated with cancer prognosis, and the impact of prognosis on suicide risk is greatest for populations with higher baseline suicide risk.

METHODS

The authors identified patients (≥16 years old) with newly diagnosed cancers from 2000 to 2019 in the Surveillance, Epidemiology, and End Results database, representing 27% of US cancers. Multiple primary-standardized mortality ratios (SMR) were used to estimate the relative risk of suicide within 6 months of diagnosis compared to the general US population, adjusted for age, sex, race, and year of follow-up. Suicide rates by 20 most common cancer sites were compared with respective 2-year overall survival rates (i.e., prognosis) using a weighted linear regression model.

RESULTS

Among 6,754,704 persons diagnosed with cancer, there were 1610 suicide deaths within 6 months of diagnosis, three times higher than the general population (SMR = 3.1; 95% confidence interval, 3.0-3.3). Suicide risk by cancer site was closely associated with overall prognosis (9.5%/percent survival deficit, R2  = 0.88, p < .0001). The association of prognosis with suicide risk became attenuated over time. For men, the risk of suicide increased by 2.8 suicide deaths per 100,000 person-years (p < .0001) versus 0.3 in women (p < .0001). The risk was also higher for persons ≥60 old and for the White (vs. Black) race.

CONCLUSIONS

Poorer prognosis was closely associated with suicide risk early after cancer diagnosis and had a greater effect on populations with higher baseline risks of suicide. This model highlights the need for enhanced psychiatric surveillance and continued research in this patient population.

Adjuvant Capecitabine for Biliary Cancer and the Importance of Looking Beyond P-Values

This article continues the discussion on the results of the BILCAP trial and advocates for careful examination and consideration of data in its entirety to inform a clinician’s decision.

MGMT promoter methylation in 1p19q-intact gliomas

OBJECTIVE

Standard-of-care for 1p19q-intact anaplastic gliomas is defined by the international randomized phase III CATNON trial, which found an overall survival (OS) benefit for adjuvant temozolomide (TMZ) when added to radiotherapy. Paradoxically, TMZ did not appear to benefit patients with IDH-wildtype gliomas, regardless of MGMT promoter status. The authors concluded that well-powered prospective study on the clinical efficacy of TMZ for patients with IDH-wildtype anaplastic gliomas (meeting criteria for glioblastoma) is warranted. Given that the prognostic and predictive role of MGMT status for grade 2-3 gliomas is unresolved, we determined the effect of MGMT status on OS in patients with 1p19q-intact gliomas in the National Cancer Database (NCDB).

METHODS

We queried the NCDB from 2018 to 2019 for patients with diffuse (grade 2) and anaplastic (grade 3) IDH-wildtype or -mutant astrocytomas who received chemotherapy with follow-up through 2022. The Kaplan-Meier method and Cox proportional hazards regressions models were used to determine the association of MGMT with OS.

RESULTS

We identified 1514 patients who were newly diagnosed with IDH-wildtype (n = 802, 33% methylated) or -mutant astrocytomas (n = 712, 48% methylated) and received chemotherapy during initial management. An unmethylated promoter was associated with poorer survival in patients with IDH-wildtype (3-year OS 34% [95%CI 29-39%] vs. 46% [95%CI 39-54%], p < .001, adjusted HR 1.53 [95%CI 1.24-1.89]) but not IDH-mutant astrocytomas (3-year OS 79% [95%CI 74-84%] vs. 80% [95%CI 75-86%], p =0 .81, HR 1.04 [95%CI 0.73-1.50]).

CONCLUSIONS

This ancillary analysis supports conclusions from the CATNON trial for adjuvant TMZ as standard-of-care for anaplastic astrocytomas (IDH-mutant and 1p19q-intact), irrespective of MGMT status. Determining the optimal strategy for diffuse gliomas that are IDH-wildtype will be particularly important. MGMT promoter methylation should be considered as a stratification factor in future clinical trials for these patients.

International Variability in the Epidemiology, Management, and Outcomes of CKD and ESKD: A Systematic Review

Key Points

There is dramatic global variability in the prevalence of ESKD. Higher per capita health care spending in each country is associated with increased delivery of care for ESKD.

Background

Approaches to treating ESKD may vary internationally on the basis of the availability of care and other factors. We performed a systematic review to understand the international variability in ESKD epidemiology, management, and outcomes.

Methods

We systematically searched PubMed for population-based studies of CKD and ESKD epidemiology and management. Population-level data from 23 predesignated nations were eligible for inclusion if they pertained to people receiving dialysis or kidney transplant for ESKD. When available, government websites were used to identify and extract data from relevant kidney registries. Measures gathered included those related to the prevalence and mortality of ESKD; the availability of nephrologists; per capita health care expenditures; and use of erythropoietin-stimulating agents.

Results

We obtained data from the United States; seven nations in Eastern Europe; four each in Western Europe, Latin America, and Africa; and three in Asia. The documented prevalence of ESKD per million population varied from a high of 3600 (Malaysia) to a low of 67 (Senegal). The annual mortality associated with ESKD varied from 31% (Ethiopia and Senegal) to 10% (the United Kingdom). Nephrologist availability per million population varied from 40 (Japan) to <1 (South Africa) and was associated with per capita health care expenditures.

Conclusions

The delivery of kidney care related to ESKD varies widely among countries. Higher per capita health care spending is associated with increased delivery of kidney care. However, in part because documentation of kidney disease varies widely, it is difficult to determine how outcomes related to ESKD may vary across nations.

Biochemical progression free and overall survival among Black men with stage IV prostate cancer in South Africa: Results from a prospective cohort study

BACKGROUND

Men of African descent are disproportionately affected by prostate cancer (PCa), and many have metastatic disease at presentation. In South Africa (SA), androgen deprivation therapy (ADT) is the first-line treatment for stage IV PCa.

OBJECTIVE

To identify predictors of overall survival (OS) in Black South African men with stage IV PCa treated with ADT.

DESIGN, SETTING, AND PARTICIPANTS

Men diagnosed with prostate cancer (3/22/2016-10/30/2020) at Chris Hani Baragwanath Academic Hospital in Soweto, Johannesburg, were recruited for the Men of African Descent with Cancer of the Prostate study. We included men with newly diagnosed stage IV PCa treated with ADT who had a prostate-specific antigen (PSA) level drawn prior to initiation of ADT and had ≥1 PSA drawn ≥12 weeks after ADT start.

OUTCOMES MEASURES AND STATISTICAL ANALYSIS

We used Kaplan-Meier statistics to estimate OS and Cox regression models to identify predictors of OS.

RESULTS AND LIMITATIONS

Of the 1097 men diagnosed with prostate cancer, we included 153 men with stage IV PCa who received ADT and met PSA requirements. The median age was 68.0 years (interquartile range 64-73 years). Median OS from time of ADT initiation was 3.39 years (95% confidence interval (CI): 3.14%-noncalculable), while biochemical progression-free survival was 2.36 years (95% CI: 2.03%-3.73%). Biochemical progression (HR 3.52, 95% CI: 1.85%-6.70%), PSA nadir level >4 ng/mL (HR 3.77, 95% CI: 1.86%-7.62%), alkaline phosphatase level at diagnosis >150 IU/dL (HR 3.09, 95% CI: 1.64%-5.83%), and hemoglobin at diagnosis <13.5 g/dL (HR 2.90, 95% CI: 1.28%-6.56%) were associated with worse OS.

CONCLUSIONS

In this study, we identified factors associated with poor OS among Black South African men with stage IV PCa treated with ADT. These factors may be useful in identifying patients for upfront treatment escalation, including the use of docetaxel chemotherapy or escalation of therapy at the time of biochemical progression.

PATIENT SUMMARY

In this study, we found that high alkaline phosphatase level, anemia at diagnosis, and high PSA nadir after initiation of androgen deprivation therapy are associated with worse overall survival among Black South African men treated with androgen deprivation therapy for metastatic prostate cancer.

Early Onset Colorectal Cancer: A Hypothesis

The rising rates of early onset colorectal cancer are perplexing. This commentary discusses what may be causing the increase.

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.

Cancer genetic mutation prevalence in sub-Saharan Africa: A review of existing data

BACKGROUND

Cancer represents a leading cause of death worldwide. Germline mutations in several genes increase the risk of developing several cancers, including cancers of the breast, ovary, pancreas, colorectum, and melanoma. An understanding of the population prevalence of pathogenic germline variants can be helpful in the design of public health interventions, such as genetic testing, which has downstream implications for cancer screening, prevention, and treatment. While population-based studies of pathogenic germline variants exist, most such studies have been conducted in White populations. Limited data exist regarding the prevalence of germline mutations within sub-Saharan African populations.

MATERIALS AND METHODS

We identified countries defined as sub-Saharan Africa by the World Bank and conducted a scoping literature review using PubMed. For each country, we identified and summarized studies that focused on the prevalence of germline genetic mutations with sample sizes >10 and in a population directly from sub-Saharan Africa, either with or without diseases associated with the relevant genetic mutations. Studies that evaluated the prevalence of somatic or likely benign variants were excluded.

RESULTS

Within the 48 countries in sub-Saharan Africa, we identified 34 studies which meet the inclusion criteria. Twenty studies were conducted in South Africa, Nigeria, or Burkina Faso; four countries had more than two published papers. We found that 33 of 48 countries in sub-Saharan Africa lacked any genetic studies. Notably, there has been an increase in relevant studies starting in 2020. Importantly, of the 34 studies identified, 29 included data on BRCA1 or BRCA2. Data on the prevalence of mutations contributing to familial cancer syndromes other than BRCA1 and BRCA2 was limited.

CONCLUSIONS

While some progress has been made towards understanding the prevalence of germline mutations in cancer susceptibility genes, the characterization of genetic mutations among sub-Saharan African populations remains strikingly incomplete. Given the genetic diversity in the region, there remains a great need for large-scale, population-based studies to understand the prevalence of germline pathogenic variants and adequately capture all the subpopulations in this part of the world.

MGMT Promoter Methylation Predicts Overall Survival after Chemotherapy for 1p/19q-Codeleted Gliomas

PURPOSE

While MGMT promoter methylation (mMGMT) is predictive of response to alkylating chemotherapy and guides treatment decisions in glioblastoma, its role in grade 2 and 3 glioma remains unclear. Recent data suggest that mMGMT is prognostic of progression-free survival in 1p/19q-codeleted oligodendrogliomas, but an effect on overall survival (OS) has not been demonstrated.

EXPERIMENTAL DESIGN

We identified patients with newly diagnosed 1p/19q-codeleted gliomas and known MGMT promoter status in the National Cancer Database from 2010 to 2019. Multivariable Cox proportional hazards regression modeling was used to assess the effect of mMGMT on OS after adjusting for age, sex, race, comorbidity, grade, extent of resection, chemotherapy, and radiotherapy.

RESULTS

We identified 1,297 eligible patients, 938 (72.3%) of whom received chemotherapy in their initial course of treatment. The MGMT promoter was methylated in 1,009 (77.8%) patients. Unmethylated MGMT (uMGMT) was associated with worse survival compared with mMGMT [70% {95% confidence interval (CI), 64%-77%} vs. 81% (95% CI, 78%-85%); P < 0.001; adjusted HR (aHR), 2.35 (95% CI, 1.77-3.14)]. uMGMT was associated with worse survival in patients who received chemotherapy [63% (95% CI, 55-73%) vs. 80% (95% CI, 76%-84%); P < 0.001; aHR, 2.61 (95% CI, 1.89-3.60)] but not in patients who did not receive chemotherapy [P = 0.38; HR, 1.31 (95% CI, 0.71-2.42)]. Similar results were observed regardless of World Health Organization grade and after single- or multiagent chemotherapy.

CONCLUSIONS

Our study demonstrates an association between mMGMT and OS in 1p/19q-codeleted gliomas. MGMT promoter status should be considered as a stratification factor in future clinical trials of 1p/19q-codeleted gliomas that use OS as an endpoint.

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.

MGMT promoter methylation in 1p19q-intact gliomas

Objective

Standard-of-care for 1p19q-intact anaplastic gliomas is defined by the international randomized phase III CATNON trial, which found an overall survival (OS) benefit for adjuvant temozolomide (TMZ) when added to radiotherapy. Paradoxically, TMZ did not appear to benefit patients with IDH-wildtype gliomas, regardless of MGMT promoter status. The authors concluded that well-powered prospective study on the clinical efficacy of TMZ for patients with IDH-wildtype anaplastic gliomas (meeting criteria for glioblastoma) is warranted. Given that the prognostic and predictive role of MGMT status for grade 2-3 gliomas is unresolved, we determined the effect of MGMT status on OS in patients with 1p19q-intact gliomas in the National Cancer Database (NCDB).

Methods

We queried the NCDB from 2018-2019 for patients with IDH-wildtype or -mutant astrocytomas who received chemotherapy with follow-up through 2022. The Kaplan-Meier method and Cox proportional hazards regressions models were used to determine the association of MGMT with OS.

Results

We identified 1,514 patients who were newly diagnosed with IDH-wildtype (n = 802, 33% methylated) or - mutant astrocytomas (n = 712, 48% methylated) and received chemotherapy during initial management. An unmethylated promoter was associated with poorer survival in patients with IDH-wildtype (3-year OS 34% [95%CI 29-39%] vs. 46% [95%CI 39-54%], p < .001, adjusted HR 1.53 [95%CI 1.24-1.89]) but not IDH-mutant astrocytomas (3-year OS 79% [95%CI 74-84%] vs. 80% [95%CI 75-86%], p = .81, HR 1.04 [95%CI 0.73-1.50]).

Conclusions

This ancillary analysis supports adjuvant TMZ as standard-of-care for anaplastic astrocytomas (IDH-mutant and 1p19q-intact), irrespective of MGMT status. Determining the optimal strategy for diffuse gliomas that are IDH-wildtype will be particularly important. MGMT promoter methylation should be considered as a stratification factor in future clinical trials for these patients.

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.

Prognostic and therapeutic impact of the KRAS G12C mutation in colorectal cancer

KRAS G12C mutations are critical in the pathogenesis of multiple cancer types, including non-small cell lung (NSCLC), pancreatic ductal adenocarcinoma (PDAC), and colorectal (CRC) cancers. As such, they have increasingly become a target of novel therapies in the management of these malignancies. However, the therapeutic success of KRAS G12C inhibitors to date has been far more limited in CRC and PDAC than NSCLC. In this review, we briefly summarize the biochemistry of KRAS targeting and treatment resistance, highlight differences in the epidemiology of various G12C-mutated cancers, and provide an overview of the published data on KRAS G12C inhibitors for various indications. We conclude with a summary of ongoing clinical trials in G12C-mutant CRC and a discussion of future directions in the management of this disease. KRAS G12C mutation, targeted therapies, colorectal cancer, non-small cell lung cancer, pancreatic cancer, drug development.

Highlights of ASCO 2023

Considering presentations at this year’s ASCO annual meeting, this editorial highlights a number of studies of interest, from adjuvant therapy studies to tumor agnostic therapy.

A Multi-Institutional Study of Barriers to Cervical Cancer Care in Sub-Saharan Africa

Purpose

The global rise in cancer incidence has been accompanied by disproportionately high morbidity and mortality rates in low- and middle-income countries. Many patients who are offered potentially curative treatment for cervical cancer in low- and middle-income countries never return to start treatment for reasons that are poorly documented and little understood. We investigated the interplay of sociodemographic, financial, and geographic factors as barriers to care among such patients in Botswana and Zimbabwe.

Methods and Materials

Patients seen in consultation between 2019 and 2021 who were >3 months late for an appointment to initiate definitive treatment were contacted via telephone and invited to complete a survey. Afterward, an intervention connected patients with resources and counseling to return for treatment. Follow-up data were collected 3 months later to ascertain the outcomes of the intervention. Fisher exact tests analyzed the relationship between the putative number and types of barriers and demographics.

Results

We recruited 40 women who initially presented for oncology care but did not return for treatment at [Princess Marina Hospital] in Botswana (n = 20) and [Parirenyatwa General Hospital] in Zimbabwe (n = 20) to complete the survey. Overall, married women experienced more barriers than unmarried women (P < .001), and unemployed women were 10 times more likely to report a financial barrier than employed women (P = .02). In Zimbabwe, financial barriers and belief-associated barriers (eg, fear of treatment) were reported. In Botswana, many patients noted scheduling obstacles associated with administrative delays and COVID-19. At follow-up, 16 Botswana patients and 4 Zimbabwe patients had returned for treatment.

Conclusions

Financial and belief barriers identified in Zimbabwe showcase the importance of targeting cost and health literacy to reduce apprehensions. In Botswana, administrative challenges could be addressed with patient navigation. Improving our understanding of the specific barriers to cancer care could enable us to help patients who might otherwise default.

Global Incidence of IgA Nephropathy by Race and Ethnicity: A Systematic Review

Key Points

In 16 studies conducted abroad, IgA nephropathy incidence varied from 0.06 in South Africa to 4.2 per 100,000 in Japan. Globally, the incidence of IgA nephropathy seemed higher in Asians than in non-Asians and higher in male patients than in female patients. Five studies conducted in the United States found no consistent difference in incidence between Black patients and White patients.

Background

The reported incidence of IgA nephropathy varies widely across studies and may vary on the basis of race/ethnicity. This study systematically reviewed the incidence of IgA nephropathy in the United States and other countries and explored variability on the basis of the racial/ethnic composition and other demographic characteristics of different populations.

Methods

This was a systematic review. Studies were eligible for inclusion if they contained data collected from January 1, 1974, to December 31, 2021, and reported IgA nephropathy incidence at a population level (i.e. , cases of IgA nephropathy per 100,000 population).

Results

Five US and 16 international studies were included; three of the US studies reported the race-specific incidence of IgA nephropathy. In the United States, the reported incidence of IgA nephropathy ranged from 0.39 per 100,000 in Tennessee to 1.4 per 100,000 in Minnesota; internationally, IgA nephropathy ranged from 0.06 per 100,000 in South Africa to 4.2 per 100,000 in Japan. Findings regarding the incidence of IgA nephropathy in the United States by race were inconsistent: One study found a higher incidence among White patients compared with Black patients, one study found a lower incidence in White patients, and one study found no difference. Globally, the incidence of IgA nephropathy seemed to be higher in Asian than in non-Asian populations and higher in male patients than in female patients.

Conclusions

Reported incidence of IgA nephropathy varies widely; there is no consensus regarding the relationship between race and IgA nephropathy. Incidence rates seemed to be higher in Asians than non-Asians and in male patients than female patients. We recommend that future studies should report IgA nephropathy incidence rates by race/ethnicity and account for the demographic characteristics of the background population.

Self-adherence to post-colonoscopy consults in patients undergoing diagnostic colonoscopy: Findings from a cross-sectional, quantitative survey at a South African quaternary hospital

Post-colonoscopy consults empower patients to make informed decisions around their subsequent treatment, and non-compliance with these consults ("no-shows") hinders disease management. There is a paucity in the literature regarding self-adherence to post-colonoscopy consults in resource-limited settings such as South Africa. An understanding of self-adherence to post-colonoscopy consults in this setting is required to establish whether improved interventions are needed, and what specific elements of self-adherence should be addressed with these interventions. The objective of this hypothesis-generating, cross-sectional, quantitative survey was to conduct a baseline assessment of cognitive, motivational, social, and behavioural variables related to self-adherence to post-colonoscopy consults in patients who underwent diagnostic colonoscopy at a South African quaternary hospital. The Adherence Determinants Questionnaire (ADQ) was administered in 47 patients to establish a baseline assessment of elements related to self-adherence to post-colonoscopy consults, including interpersonal aspects of care, perceived utility, severity, susceptibility, subjective norms, intentions, and supports/barriers. ADQ scores were transformed to a percentage of the maximum score for each element (100.0%). The overall mean transformed ADQ score was 57.8%. The mean transformed scores for specific ADQ components were as follows: subjective norms (40.8%), perceived severity (55.4%), perceived utility (56.6%), intentions (59.4%), supports/barriers (59.9%), interpersonal aspects (62.2%), and perceived susceptibility (65.9%). There were no statistically significant differences in overall mean transformed ADQ scores and individual ADQ elements across categories of participant age (p-values ranging between 0.180 and 0.949 when compared between participants ≤40 years and >40 years old), gender (p-values ranging between 0.071 and 0.946 when compared between males and females), and race (p-values ranging between 0.119 and 0.774 when compared between Black Africans and non-Black Africans). Our findings suggest a general need for appropriate interventions to improve self-adherence to post-colonoscopy consults in our setting.

Effects of Genetic Polymorphisms of Drug Metabolizing Enzymes and co-Medications on Tamoxifen Metabolism in Black South African Women with Breast Cancer

Clinical outcomes of tamoxifen (TAM) treatment show wide interindividual variability. Comedications and genetic polymorphisms of enzymes involved in TAM metabolism contributes to this variability. Drug-drug and drug-gene interactions have seldom been studied in African Black populations. We evaluated the effects of commonly co-administered medicines on TAM pharmacokinetics in a cohort of 229 South African Black female patients with hormone-receptor positive breast cancer. We also investigated the pharmacokinetic effects of genetic polymorphism in enzymes involved in TAM metabolism, including the variants CYP2D6*17 and *29, which have been mainly reported in people of African descent. TAM and its major metabolites, N-desmethyltamoxifen (NDM), 4-OH-tamoxifen, and endoxifen (ENDO), were quantified in plasma using the liquid chromatography-mass spectrometry. The GenoPharm open array was used to genotype CYP2D6, CYP3A5, CYP3A4, CYP2B6, CYP2C9, and CYP2C19. Results showed that CYP2D6 diplotype and CYP2D6 phenotype significantly affected endoxifen concentration (P < 0.001 and P < 0.001). CYP2D6*17 and CYP2D6*29 significantly reduced the metabolism of NDM to ENDO. Antiretroviral therapy had a significant effect on NDM levels and the TAM/NDM and NDM/ENDO metabolic ratios but did not result in significant effects on ENDO levels. In conclusion, CYP2D6 polymorphisms affected endoxifen concentration and the variants CYP2D6*17 and CYP2D6*29 significantly contributed to low exposure levels of ENDO. This study also suggests a low risk of drug-drug interaction in patients with breast cancer on TAM.

Cost-effectiveness of adjuvant chemotherapy for high-risk stage II and stage III colon cancer in South Africa

BACKGROUND

Colon cancer incidence is rising in low- and middle-income countries (LMICs), where resource limitations and cost often dictate treatment decisions. In this study, we evaluate the cost-effectiveness of adjuvant chemotherapy for high-risk stage II and stage III colon cancer treatment in South Africa (ZA) and illustrate how such analyses can inform cancer treatment recommendations in a LMIC.

METHODS

We created a decision-analytic Markov model to compare lifetime costs and outcomes for patients with high-risk stage II and stage III colon cancer treated with three adjuvant chemotherapy regimens in a public hospital in ZA: capecitabine and oxaliplatin (CAPOX) for 3 and 6 months, and capecitabine for 6 months, compared to no adjuvant treatment. The primary outcome was the incremental cost-effectiveness ratio (ICER) in international dollars (I$) per disability-adjusted life-year (DALY) averted, at a willingness-to-pay (WTP) threshold equal to the 2021 ZA gross domestic product per capita (I$13,764/DALY averted).

RESULTS

CAPOX for 3 months was cost-effective for both patients with high-risk stage II and patients with stage III colon cancer (ICER = I$250/DALY averted and I$1042/DALY averted, respectively), compared to no adjuvant chemotherapy. In subgroup analyses of patients by tumor stage and number of positive lymph nodes, for patients with high-risk stage II colon cancer and T4 tumors, and patients with stage III colon cancer with T4 or N2 disease. CAPOX for 6 months was cost-effective and the optimal strategy. The optimal strategy in other settings will vary by local WTP thresholds. Decision analytic tools can be used to identify cost-effective cancer treatment strategies in resource-constrained settings.

CONCLUSION

Colon cancer incidence is increasing in low- and middle-income countries, including South Africa, where resource constraints can impact treatment decisions. This cost-effectiveness study evaluates three systemic adjuvant chemotherapy options, compared to surgery alone, for patients in South African public hospitals after surgical resection for high-risk stage II and stage III colon cancer. Doublet adjuvant chemotherapy (capecitabine and oxaliplatin) for 3 months is the cost-effective strategy and should be recommended in South Africa.

Risk of Squamous Cell Carcinoma of the Breast Following Postmastectomy Implant Reconstruction in Women With Breast Cancer and Carcinoma in Situ

This cohort study uses national surveillance data to describe the incidence and risk of squamous cell carcinoma after postmastectomy implant reconstruction in women with breast cancer.

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.

A Transcriptome-Based Precision Oncology Platform for Patient-Therapy Alignment in a Diverse Set of Treatment-Resistant Malignancies

Predicting in vivo response to antineoplastics remains an elusive challenge. We performed a first-of-kind evaluation of two transcriptome-based precision cancer medicine methodologies to predict tumor sensitivity to a comprehensive repertoire of clinically relevant oncology drugs, whose mechanism of action we experimentally assessed in cognate cell lines. We enrolled patients with histologically distinct, poor-prognosis malignancies who had progressed on multiple therapies, and developed low-passage, patient-derived xenograft models that were used to validate 35 patient-specific drug predictions. Both OncoTarget, which identifies high-affinity inhibitors of individual master regulator (MR) proteins, and OncoTreat, which identifies drugs that invert the transcriptional activity of hyperconnected MR modules, produced highly significant 30-day disease control rates (68% and 91%, respectively). Moreover, of 18 OncoTreat-predicted drugs, 15 induced the predicted MR-module activity inversion in vivo. Predicted drugs significantly outperformed antineoplastic drugs selected as unpredicted controls, suggesting these methods may substantively complement existing precision cancer medicine approaches, as also illustrated by a case study.

SIGNIFICANCE

Complementary precision cancer medicine paradigms are needed to broaden the clinical benefit realized through genetic profiling and immunotherapy. In this first-in-class application, we introduce two transcriptome-based tumor-agnostic systems biology tools to predict drug response in vivo. OncoTarget and OncoTreat are scalable for the design of basket and umbrella clinical trials. This article is highlighted in the In This Issue feature, p. 1275.

Smoking is Not Associated with Lung Metastasis in Pancreatic Cancer

Smoking is a risk factor for pulmonary metastasis in various malignancies. We investigated this association for pancreatic ductal adenocarcinoma (PDAC). We conducted a retrospective 1:2 case-control study of consecutive patients who underwent PDAC resection (2011-2021). Cases ultimately developed lung metastases and controls did not. Of 744 patients we identified 53 cases and 106 matched controls. Twenty-five (47%) cases and 50 (47%) matched controls had a history of smoking (p = 1.0). This indicates that smoking is not associated with increased risk of pulmonary metastasis in resectable PDAC. Further research is needed to elucidate tumor and parenchymal factors influencing metastatic site.

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.

Abstract P1-01-03: The Impact of Comorbid HIV infection on Neoadjuvant and Adjuvant Chemotherapy Relative Dose Intensity in South African Breast Cancer Patients

Introduction In the South African Breast Cancer and HIV Outcomes (SABCHO) study, early-stage breast cancer patients living with HIV, compared to their HIV-negative counterparts, demonstrated higher overall mortality and lower rates of pathologic complete response if treated with neoadjuvant chemotherapy. We aimed to determine if comorbid HIV also impacted receipt of timely and complete neoadjuvant and adjuvant chemotherapy. Methods We retrospectively identified Black, stage I-III SABCHO participants diagnosed with breast cancer from June 2015 to July 2019 and who received at least 2 doses of neoadjuvant or adjuvant chemotherapy at either Charlotte Maxeke Johannesburg Academic Hospital (Gauteng) or Grey’s Hospital (KwaZulu-Natal). Data on the originally prescribed chemotherapy regimen and the dose and timing of all received chemotherapy was extracted from patients’ medical records, as well as values from all complete blood counts and metabolic panels performed during treatment. Relative dose intensity (RDI) was calculated for each agent in the prescribed regimen with the mean RDI of all agents representing the RDI of the full regimen. We assessed for associations between full regimen RDI and HIV status using a multivariable linear regression model that included demographic and clinical covariates also shown to impact RDI. We also compared rates of myelosuppression, alkaline phosphatase elevation, and creatinine elevation using linear regression. Using previously collected survival data, we compared overall mortality based on overall RDI above or below 0.85. Results We analyzed data from 325 eligible subjects, 166 of whom were living with HIV. No differences based on HIV status were appreciated in the prescribed chemotherapy regimens. For women without HIV median RDI was 0.87 (interquartile range (IQR) 0.77-0.94) and, in those living with HIV, it was 0.89 (IQR 0.77-0.95). HIV status showed no significant association with RDI on multivariable analysis, and the only patient characteristics associated with RDI were estrogen/progesterone receptor (ER/PR) and HER2 status. Patients living with HIV experienced more CTCAE v5.0 grade 3+ anemia and leukopenia than those without HIV (anemia: 10.8% vs 1.9%, p=0.001; leukopenia: 8.4% vs 1.9%, p=0.008) and were more likely to receive at least one dose of filgrastim (24.7% vs 10.7%, p=0.001). Receipt of RDI greater or less than 0.85 did not predict overall mortality in the full cohort or HIV status subgroups. A trend towards improved survival with RDI greater than 0.85 was seen among the 69 participants with ER/PR negative disease (hazard ratio: 0.60, 95% confidence interval: 0.30-1.21, p = 0.15). Conclusions Neoadjuvant and adjuvant chemotherapy RDI did not differ by HIV status among women in the SABCHO study, although women living with HIV experienced more myelotoxicity during treatment. Efforts to reduce chemotherapy dose reduction and delays should target all South African breast cancer patients.

Citation Format: Daniel S. O’Neil, Oluwatosin A Ayeni, Hayley A. Farrow Woolridge, Wenlong Carl Chen, Georgia Demetriou, Ines Buccimazza, Sharon Cacala, Maureen Joffe, Michael Antoni, Gilberto Lopes, Yoanna Pumpalova, Witness Mapanga, Judith S. Jacobson, Katherine D. Crew, Alfred I. Neugut, Paul Ruff, Herbert Cubasch. The Impact of Comorbid HIV infection on Neoadjuvant and Adjuvant Chemotherapy Relative Dose Intensity in South African Breast Cancer Patients [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 P1-01-03.

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 &lt; 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 &lt; 40 years of age were less likely to adhere to tamoxifen than women &gt;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.

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.

Data From a One-Stop-Shop Comprehensive Cancer Screening Center

PURPOSE

Cancer is the second leading cause of death globally. However, by implementing evidence-based prevention strategies, 30%-50% of cancers can be detected early with improved outcomes. At the integrated cancer prevention center (ICPC), we aimed to increase early detection by screening for multiple cancers during one visit.

METHODS

Self-referred asymptomatic individuals, age 20-80 years, were included prospectively. Clinical, laboratory, and epidemiological data were obtained by multiple specialists, and further testing was obtained based on symptoms, family history, individual risk factors, and abnormalities identified during the visit. Follow-up recommendations and diagnoses were given as appropriate.

RESULTS

Between January 1, 2006, and December 31, 2019, 8,618 men and 8,486 women, average age 47.11 ± 11.71 years, were screened. Of 259 cancers detected through the ICPC, 49 (19.8%) were stage 0, 113 (45.6%) stage I, 30 (12.1%) stage II, 25 (10.1%) stage III, and 31(12.5%) stage IV. Seventeen cancers were missed, six of which were within the scope of the ICPC. Compared with the Israeli registry, at the ICPC, less cancers were diagnosed at a metastatic stage for breast (none v 3.7%), lung (6.7% v 11.4%), colon (20.0% v 46.2%), prostate (5.6% v 10.5%), and cervical/uterine (none v 8.5%) cancers. When compared with the average stage of detection in the United States, detection was earlier for breast, lung, prostate, and female reproductive cancers. Patient satisfaction rate was 8.35 ± 1.85 (scale 1-10).

CONCLUSION

We present a proof of concept study for a one-stop-shop approach to cancer screening in a multidisciplinary outpatient clinic. We successfully detected cancers at an early stage, which has the potential to reduce morbidity and mortality as well as offer substantial cost savings.

Involvement in Chemotherapy Decision Making among Patients with Stage II and III Colon Cancer

Background. To explore preferred and actual involvement in chemotherapy decision making among stage II and III colon cancer (CC) patients by sociodemographic, interpersonal, and intrapersonal communication factors. Methods. Cross-sectional exploratory study collecting self-reported survey data from stage II and III CC patients from 2 cancer centers located in northern Manhattan. Results. Of 88 patients approached, 56 completed the survey. Only 19.3% reported shared involvement in their chemotherapy decisions. We observed significant differences in preferred involvement by gender, with women preferring more physician-controlled decisions. CC patients with higher levels of decisional self-efficacy significantly preferred shared decisions (F = 4.4 [2], P = 0.02). Actual involvement in decisions differed by race (physician controlled 33% for White v. 67% for Other, P < 0.01), age (shared control 18% for ≤55 y, 55% for 55-64 y, and 27% for 65+ y, P = 0.04), and perception of choice (shared control 73% "yes" v. 27% "no,"P = 0.02). Actual or preferred involvement did not differ by stage. Significantly higher levels of medical mistrust (discrimination t = 2.8 [50], P = 0.01; lack of support t = 3.6 [49], P < 0.01), and lower levels of decisional self-efficacy (t = 2.5 [49], P = 0.01) were reported among women. Discussion. Reports of shared involvement around chemotherapy decisions is limited among CC patients. Factors influencing preferred versus actual chemotherapy decision making are complex and may differ; hence, more research is needed to understand and address factors contributing to discordance between preferred and actual involvement in chemotherapy decision making for CC patients.

Highlights

Shared involvement around chemotherapy decisions remains limited for patients diagnosed with colon cancer.Sociodemographic (age, race, gender), interpersonal (medical mistrust), and intrapersonal (decisional self-efficacy, perception of choice) factors that influence preferred involvement in chemotherapy decision making may differ from those influencing actual involvement in chemotherapy decision making.Shared involvement in chemotherapy decisions may look different than currently conceptualized, notably when uncertainty around the benefits exists.

Predictors of treatment refusal in patients with colorectal cancer: A systematic review

This systematic review was conducted to investigate predictors of treatment refusal in colorectal cancer (CRC) patients. An understanding of these predictors would inform statistical models for the identification of high-risk patients who might benefit from interventions that seek to improve treatment compliance. We performed a search of PubMed and Scopus to identify potentially relevant studies on predictors of treatment refusal in CRC patients that were published between January 1, 2000 and December 31, 2021. We screened manuscripts using predefined eligibility criteria. Information on study design, study location, patient characteristics, treatments, rates and predictors of treatment refusal, and the impact of treatment refusal on mortality or survival were collected from eligible studies. Study quality was assessed using the Newcastle-Ottawa score. The overall findings of the review process were summarized using descriptive statistics and a narrative synthesis. A total of 13 studies were included in this review. Ten studies reported on refusal of CRC surgery, refusal rate: 0.25%-3.26%; three studies reported on chemotherapy refusal (one of which reported on both surgery and chemotherapy refusal), refusal rate: 7.8%-41.5%; and one study reported on refusal of any cancer treatment, refusal rate: 8.7%. The bulk of the published literature confirmed the harmful association between treatment refusal and poor survival outcomes in CRC patients. Frequently cited predictors of treatment refusal included patient demographic characteristics (age, race, gender), clinical characteristics (disease stage, comorbidity), and factors that impact access to cancer care services (healthcare insurance, facility level). Potentially high rates of treatment refusal pose a challenge to CRC control. This review has identified several factors which must be considered when attempting to reduce treatment refusal in CRC patients. Furthermore, these factors should be tested as components of predictive risk models for this important outcome.

Risk of Anaplastic Large Cell Lymphoma Following Postmastectomy Implant Reconstruction in Women With Breast Cancer and Ductal Carcinoma in Situ

This cohort study examines the risk of anaplastic large cell lymphoma (ALCL) following postmastectomy implant reconstruction among US women with breast cancer and ductal carcinoma in situ (DCIS).

Urinary parabens and breast cancer risk: Modification by LINE-1 and LUMA global DNA methylation, and associations with breast cancer defined by tumor promoter methylation status

Parabens are a group of alkyl esters of p-hydroxybenzoic acid added to consumer products to prevent the growth of harmful bacteria and molds. Parabens are hypothesized to increase the risk of breast cancer (BC); however, no study has examined the interactions between parabens, global DNA methylation (DNAm), and BC risk. We examined the modifying effects of DNAm on the associations between parabens and BC, and whether parabens were associated with BC defined by tumor promoter methylation status. Participants included 708 cases and 598 controls from the Long Island Breast Cancer Study Project. Methylparaben (MPB), propylparaben, and butylparaben levels were measured in spot urine samples. Global DNAm was measured by analysis of long interspersed elementes-1 (LINE-1) and the luminometric methylation assay (LUMA). The promoter methylation status of 13 genes was measured in tumor samples from 509 cases. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between parabens and BC stratified by LINE-1/LUMA, and between parabens and gene-specific promoter methylation-defined BC. Outcome heterogeneity was evaluated using ratios of ORs (RORs). We assessed the joint effects of the multiple parabens using quantile g-computation. The highest versus lowest tertile of MPB and a one-quantile increase in all parabens were associated with ORs of 1.46 (95% CI = 0.96-2.23) and 1.32 (95% CI = 1.02-1.71), respectively, among women with hypomethylated LINE-1. A one-ln unit increase in MPB was associated with a 25% increase in the odds of hypomethylated (vs. hypermethylated) CCND2 promoter-defined BC (ROR = 1.25, 95% CI = 1.06-1.48), and a one-quantile increase in all parabens was associated with a 55% increase in the odds of hypomethylated (vs. hypermethylated) CCND2 promoter-defined BC (ROR = 1.55, 95% CI = 1.04-2.32). Exposure to parabens may increase the risk of BC among women with hypomethylated global DNAm and may increase the risk of tumors with gene-specific hypomethylated promoter regions.

Prevalence of multimorbidity in men of African descent with and without prostate cancer in Soweto, South Africa

OBJECTIVE

With increases in chronic disease, men with prostate cancer are likely to have at least one other chronic health condition. The burden and complexity of each additional chronic disease may complicate prostate cancer treatment and reduce survival. In this paper, we describe the frequency of multimorbid chronic diseases, HIV and depression among men in Soweto, South Africa (SA) with and without prostate cancer and determine whether the presence of multimorbid diseases is associated with metastatic and high-risk, non-metastatic prostate cancer.

METHODS

A population-based case-control study on prostate cancer was conducted among black men in Soweto. All participants completed a baseline survey on sociodemographics, lifestyle, and comorbid medical conditions. All participants completed a depression screening survey and HIV testing at enrolment. Blood pressure measurements and blood testing for fasting glucose, total cholesterol, and high-density lipoprotein were performed on a subset of randomly selected cases and controls. For men with prostate cancer, clinical T staging was assessed with the digital rectal examination, the diagnosis was confirmed with a biopsy and PSA levels were assessed at presentation. The metastatic staging was assessed by bone scans, and this was confirmed with PSMA PET scans, CT scans and X-rays, standard for our resource-constrained setting. Normal PSA scores were used as an inclusion criterion for controls.

RESULTS

Of the 2136 men (1095 with prostate cancer and 1041 controls) included in the analysis, 43.0% reported at least one chronic metabolic disease; 24.1% reported two metabolic diseases; 5.3% reported three metabolic diseases; and 0.3% reported four metabolic diseases. Men with prostate cancer were more likely to report a multimorbid chronic metabolic disease compared to controls (p<0.001) and more likely to test positive for HIV (p = 0.05). The majority of men (66.2%) reported at least one metabolic disease, tested negative for HIV and had a negative depression screen. The clinical characteristics of men with prostate cancer, were as follows: 396 (36.2%) had a Gleason score of 8 and above; 552 (51.3%) had a PSA score of >20ng/ml; 233 (21.7%) had confirmed metastatic prostate cancer at diagnosis. Older age was associated with metastatic prostate cancer (OR = 1.043 95% CI:1.02-1.07) and NCCN defined high-risk non-metastatic prostate cancer (OR = 1.03 95% CI:1.01-1.05), whilst being hypertensive was protective (OR = 0.63 95% CI:0.47-0.84 and OR = 0.55 95% CI:0.37-0.83) respectively for metastatic and high-risk, non-metastatic prostate cancer.

CONCLUSION

The high prevalence of multimorbid metabolic diseases and HIV among men with prostate cancer represents a public health concern in South Africa. There is a need to effectively address multiple chronic diseases among men with prostate cancer by incorporating coordinated care models.

Prevalence of monoclonal gammopathy of undetermined significance in Black South African men

BACKGROUND

Both multiple myeloma and its precursor, monoclonal gammopathy of undetermined significance (MGUS), occur twice as often within Black compared to White populations, suggesting that racial disparities lie within the development of MGUS. Nonetheless, MGUS has been studied mainly in White cohorts; the study that first described the natural history of MGUS was conducted in 97.3% White Olmsted County, Minnesota.

METHODS

We determined the prevalence of MGUS among 386 Black South African (SA) men >30 years at Chris Hani Baragwanath Hospital in Johannesburg. We conducted serum protein electrophoresis and free light chain quantification to define MGUS by the same criteria as the Olmsted County studies. We also investigated the association between MGUS and various clinical factors, including HIV infection and smoking.

RESULTS

We found the prevalence of MGUS to be 8.03% (95%CI 5.32-10.74), nearly 1.6-fold higher than in the White Olmsted County male population. In a univariable logistic regression model, MGUS was associated with HIV status (Odds Ratio, OR 2.39, 95%CI 0.95-5.49), but in an adjusted model that included body mass index and cigarette use, the association was not statistically significant. Those who were current (vs. never) cigarette smokers were more likely to have MGUS in both univariable (OR 5.60, 95%CI 2.16-17.42) and multivariable models (OR 4.49, 95%CI 1.63-14.56).

CONCLUSIONS

The prevalence of MGUS in Black SA men is substantially higher than in White populations and may be associated with HIV status and cigarette use.

IMPACT

Racial disparities in MGUS exist and may be associated with potentially modifiable risk factors.

Testing the generalizability of ancestry-specific polygenic risk scores to predict prostate cancer in sub-Saharan Africa

BACKGROUND

Genome-wide association studies do not always replicate well across populations, limiting the generalizability of polygenic risk scores (PRS). Despite higher incidence and mortality rates of prostate cancer in men of African descent, much of what is known about cancer genetics comes from populations of European descent. To understand how well genetic predictions perform in different populations, we evaluated test characteristics of PRS from three previous studies using data from the UK Biobank and a novel dataset of 1298 prostate cancer cases and 1333 controls from Ghana, Nigeria, Senegal, and South Africa.

RESULTS

Allele frequency differences cause predicted risks of prostate cancer to vary across populations. However, natural selection is not the primary driver of these differences. Comparing continental datasets, we find that polygenic predictions of case vs. control status are more effective for European individuals (AUC 0.608-0.707, OR 2.37-5.71) than for African individuals (AUC 0.502-0.585, OR 0.95-2.01). Furthermore, PRS that leverage information from African Americans yield modest AUC and odds ratio improvements for sub-Saharan African individuals. These improvements were larger for West Africans than for South Africans. Finally, we find that existing PRS are largely unable to predict whether African individuals develop aggressive forms of prostate cancer, as specified by higher tumor stages or Gleason scores.

CONCLUSIONS

Genetic predictions of prostate cancer perform poorly if the study sample does not match the ancestry of the original GWAS. PRS built from European GWAS may be inadequate for application in non-European populations and perpetuate existing health disparities.

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.

Association between immigrant status and advanced cancer patients' location and quality of death

Background

Cancer patients often prefer to die at home, a location associated with better quality of death (QoD). Several studies demonstrate disparities in end‐of‐life care among immigrant populations in the United States. This study aimed to evaluate how immigrant status affects location and quality of death among patients with advanced cancer in the United States.

Methods

Data were derived from Coping with Cancer, a federally funded multi‐site prospective study of advanced cancer patients and caregivers. The sample of patients who died during the study period was weighted (N_w = 308) to reduce statistically significant differences between immigrant (N_w = 49) and nonimmigrant (N_w = 259) study participants. Primary outcomes were location of death, death at preferred location, and poor QoD.

Results

Analyses adjusted for covariates indicated that patients who were immigrants were more likely to die in a hospital than home (adjusted odds ratio [AOR], 3.33; 95% confidence interval [CI], 1.65–6.71) and less likely to die where they preferred (AOR, 0.42; 95% CI, 0.20–0.90). Furthermore, immigrants were more likely to have poor QoD (AOR, 5.47; 95% CI, 2.70–11.08).

Conclusions

Immigrants, as compared to nonimmigrants, are more likely to die in hospital settings, less likely to die at their preferred location, and more likely to have poor QoD.

Lay summary

Cancer patients typically prefer to die in their own homes, which is associated with improved quality of death.

However, disparities in end‐of‐life care among immigrant populations in the United States remain significant.

Our study found that immigrants are less likely to die in their preferred locations and more likely to die in hospital settings, resulting in poorer quality of death.

Disparities in end‐of‐life care and quality of death are prevalent among immigrants. The findings of this study illustrate that immigrants in the United States are more likely to die in hospital settings and less likely to die at their preferred location.

Predictors of overall survival among Black South African men treated with androgen-deprivation therapy for metastatic prostate cancer

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Background: Men in sub-Saharan Africa (SSA) are disproportionately affected by prostate cancer (PCa), and many have metastatic disease (mPCA) at presentation. In SSA, androgen deprivation therapy (ADT) is the first-line treatment for mPCa, and often the only available therapy. Treatment failure and death is common. We identified predictors of overall survival (OS) in Black South African (SA) men with mPCa on ADT. Methods: We performed a retrospective analysis of prospectively gathered data from men diagnosed with mPCA (3/22/2016 - 10/30/2020) at Chris Hani Baragwanath Hospital in Johannesburg, which was also a study site for the concurrent Men of African Descent and Carcinoma of the Prostate study. We included men with mPCA treated with ADT (received at least 1 dose of luteinizing hormone-releasing hormone agonist and/or had surgical castration), who had ≥1 PSA level drawn ≥12 weeks after ADT start. OS was defined from ADT start to death. PSA progression (PSA-P) definition was adapted from PCWG 3. Cox regression models were used to identify predictors of OS. PSA-P was treated as a time-dependent covariate. Results: Of 200 men with mPCa, we excluded 6 who did not receive ADT and 41 without sufficient data for PSA-P analysis. Of 153 men, 26.8% were <65 years old and 12% had a family history of PCa. Median PSA at diagnosis was 71.5 ng/mL (interquartile range (IQR) 20.7-432.6), median alkaline phosphatase level (ALP) 108 IU/L (79-224) and median hemoglobin (Hb) 13 g/dL (IQR 10-15). Median PSA nadir was 2.8 ng/mL (IQR 0.55-17.93). The rate of PSA-P at 1- and 2-years was 12.1% [95%CI 5.9-17.8] and 37.5% [95%CI 26.1-47.2]. The median follow-up was 2.75 years, and the 3-year OS was 61.9% [95%CI 52.7-72.6]. Cox proportional hazard ratio (HR) models of risk factors for OS are shown in Table 1. PSA-P was a strong predictor of OS. Men with PSA nadir >4ng/mL after ADT start had a HR for death of 3.77 [1.86-7.62]. Men with ALP >150 IU/L and those with Hb <13.5g/dL at diagnosis were also at higher risk for death (HR 3.09 [1.64-5.83] and HR 2.00 [1.28-6.56] respectively). Conclusions: Among Black men in SA treated with ADT for mPCA, PSA-P strongly predicts OS. In this cohort, high ALP and anemia at diagnosis, and PSA nadir >4ng/mL after ADT start are associated with higher risk for death. These factors can be used identify high risk men with mPCA, for whom early treatment escalation to chemotherapy should be considered. [Table: see text]

Cost-effectiveness of adjuvant chemotherapy for patients with high-risk stage II and stage III colon cancer in South Africa

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Background: Colon cancer (CC) incidence is rising globally, and case fatality rates are greatest in low-income settings, such as South Africa (SA). Adjuvant chemotherapy is standard of care for high-risk stage II and stage III CC in the US. We evaluated the cost-effectiveness of adjuvant chemotherapy for CC in SA public hospitals. Methods: We developed a decision-analytic Markov model comparing lifetime costs and outcomes for 60-year-old high-risk stage II and stage III CC patients treated in a SA public hospital with no adjuvant chemotherapy, versus: capecitabine and oxaliplatin (CAPOX) for 3 or 6 months or capecitabine for 6 months. High-risk stage II was defined as ≥1 of: T4 disease; poorly differentiated tumor; lymphovascular/perineural invasion; <12 lymph nodes dissected, bowel obstruction/perforation. Transition probabilities were derived from clinical trials estimating toxicity, disease recurrence, and survival. Costs from a SA societal perspective and utility estimates were obtained from literature and local expert opinion. The primary outcome was the incremental cost-effectiveness ratio (ICER) in international dollars (I$) per disability-adjusted life year (DALY) averted, with a willingness-to-pay (WTP) threshold equal to 2021 GDP/capita of SA (I$13,764). Results: CAPOX for 3 months was the cost-effective strategy for stage III CC at a lifetime cost of I$5,284 and 5.55 DALYs averted, compared to no adjuvant treatment. All other strategies were absolutely dominated. For high-risk stage II CC, CAPOX for 3 months was the cost-effective strategy (ICER = I$711/DALY averted). No adjuvant chemotherapy was on the efficiency frontier, with a lower lifetime cost, but no DALYs averted. The results of one-way deterministic sensitivity analyses showed that the model is most sensitive to CC recurrence rate. In a probabilistic sensitivity analysis, CAPOX for 3 months was optimal in 88% of iterations for high-risk stage II CC and 79% of iterations for stage III CC. Conclusions: CAPOX for 3 months is the cost-effective adjuvant treatment for high-risk stage II and stage III CC in SA public hospitals. This strategy offers the highest quality of life benefit for the lowest cost and is well within the WTP threshold for SA. The optimal strategy in other settings will vary according to local WTP thresholds. Base case estimates of cost-effectiveness, in order of cost. [Table: see text]