Ethnic Disparities in Adjuvant Chemotherapy for Breast Cancer Are Not Caused by Excess Toxicity in Black Patients

Dose delay, dose reduction, and early treatment discontinuation in Black and White women receiving chemotherapy for nonmetastatic breast cancer

BACKGROUND

To describe reasons for deviations from planned chemotherapy treatments in women with nonmetastatic breast cancer that contribute to less-than-planned receipt of chemotherapy.

METHODS

Electronic medical records for patients receiving chemotherapy were reviewed for adverse events and treatment modifications. Log-binomial regression models were used to estimate relative risks (RRs) with 95% CIs to examine associations between chemotherapy modifications, patient characteristics, and treatment modalities.

RESULTS

Delays in chemotherapy initiation (7%) were for surgical complications (58%), personal reasons (16%), and other (26%; port malfunction, infections, and obtaining extra imaging). Delays during chemotherapy (38%) were for infections (20%), neutropenia (13%), and personal reasons (13%). Dose reductions (38%) were for neuropathy (36%), unknown causes (9%), anemia (9%), and neutropenia (8%). Early treatment discontinuations (23%) were for neuropathy (29%). Patients receiving paclitaxel/nab-paclitaxel (RR 2.05; 95% CI, 1.47-2.87) and an anthracycline (RR 1.89; 95% CI, 1.39-2.57) reported more dose delays during chemotherapy. Black race (RR 1.46; 95% CI, 1.07-2.00), stage 3 (RR 1.79; 95% CI, 1.09-2.93), and paclitaxel/nab-paclitaxel receipt (RR 1.39; 95% CI, 1.02-1.90) increased the likelihood of dose reduction. Both Black race (RR 2.06; 95% CI, 1.35-3.15) and receipt of paclitaxel/nab-paclitaxel (RR 1.93; 95% CI, 1.19-3.13) increased the likelihood of early discontinuation. Patients receiving anthracyclines had higher rates of hospitalizations during chemotherapy (RR: 1.79; 95% CI, 1.11-2.89).

CONCLUSION

Toxicities are the most common reason for treatment modifications and need close monitoring in high-risk groups for timely intervention. Dose reductions and early treatment discontinuations occurred more for Black patients and need further study.

Racial Disparities in Breast Cancer Treatments and Adverse Events in the SEER-Medicare Data

Despite lower incidence rates, African American (AA) patients have shorter survival from breast cancer (BC) than white (W) patients. Multiple factors contribute to decreased survival, including screening disparities, later presentation, and access to care. Disparities in adverse events (AEs) may contribute to delayed or incomplete treatment, earlier recurrence, and shortened survival. Here, we analyzed the SEER-Medicare dataset, which captures claims from a variety of venues, in order to determine whether the cancer care venues affect treatment and associated adverse events. We investigated a study population whose claims are included in the Outpatient files, consisting of hospital and healthcare facility venues, and a study population from the National Claims History (NCH) files, consisting of claims from physicians, office practices, and other non-institutional providers. We demonstrated statistically and substantively significant venue-specific differences in treatment rates, drugs administered, and AEs from treatments between AA and W patients. We showed that AA patients in the NCH dataset received lower rates of treatment, but patients in the Outpatient dataset received higher rates of treatment than W patients. The rates of recorded AEs per treatment were higher in the NCH setting than in the Outpatient setting in all patients. AEs were consistently higher in AA patients than in W patients. AA patients had higher comorbidity indices and were younger than W patients, but these variables did not appear to play roles in the AE differences. The frequency of specific anticancer drugs administered in cancer- and venue-specific circumstances and their associated AEs varied between AA and W patients. The higher AE rates were due to slightly higher frequencies in the administration of drugs with higher associated AE rates in AA patients than in W patients. Our investigations demonstrate significant differences in treatment rates and associated AEs between AA and W patients with BC, depending on the venues of care, likely contributing to differences in outcomes.

Dermatologic toxicities of chemotherapy: an educational intervention for skin of color women with breast cancer

Minority patients are more likely to require dose adjustments for chemotherapy, with cultural barriers and access to medical care cited as contributory factors.

Objective

We sought to pilot an educational intervention, in the form of a pamphlet, to evaluate the effectiveness of this tool in teaching skin of color (SoC) patients about potential dermatologic toxicities of chemotherapy that are relevant to their skin type.

Methods

At a chemotherapy infusion center, SoC patients (n = 26) who were receiving chemotherapy for breast cancer voluntarily consented to read an educational pamphlet and complete a series of survey questions before and after this educational intervention.

Results

Most participants identified as female (96%), African American/Black (81%), and non-Hispanic (85%); all respondents had obtained at least a high school degree. Survey responses revealed a significant increase in knowledge about the potential dermatologic effects of cancer treatment after this intervention. Notably, 100% of participants either agreed or strongly agreed that they would like to see other doctors use this educational tool as a form of patient education, that they would recommend this pamphlet to other patients who are starting cancer treatment, and that the pamphlet was easy to understand.

Limitations

Limitations of this study include small sample size and single-institution recruitment, which may limit generalizability. Furthermore, this study only included patients who are proficient in English.

Conclusion

This study pilots an effective educational tool that addresses dermatologic toxicities of chemotherapy that are relevant to SoC patients. Further multi-institutional studies with larger sample sizes and translation to other languages can overcome the limitations of this pilot study.

Racial disparities in breast cancer treatment patterns and treatment related adverse events

The main objective of this work was to perform a comprehensive analysis and provide a race-stratified epidemiological report accounting for differences in treatment patterns and treatment related adverse events in Non-Hispanic women with breast cancer (BC). The cohort included women ≥ 18 years diagnosed with in-situ, early-stage, and late-stage BC (2005-2022). Treatment patterns included: surgery, breast radiation, chemotherapy, endocrine therapy, or biologic therapy. Treatment related adverse events were: chemotherapy complications, cardiovascular toxicities, immune-related adverse events, psychological affectations, or cognitive decline/dementia. The influence of race on the outcomes was measured via Cox proportional-hazards models. We included 17,454 patients (82% non-Hispanic Whites [NHW]). Most of the patients had a Charlson Comorbidity Score between 1 and 2 (68%), and TNM stage I (44.5%). Surgery was performed in 51.5% of the cases, while 30.6% received radiotherapy, 26.4% received chemotherapy, 3.1% received immunotherapy, and 41.2% received endocrine therapy. Non-Hispanic Blacks (NHB) had a lower probability of undergoing breast cancer surgery (aHR = 0.92, 95% CI 0.87-0.97) and of being prescribed endocrine therapy (aHR = 0.83, 95% CI 0.79-0.89), but a higher probability of receiving adjuvant radiotherapy (aHR = 1.40, 95% CI 1.29-1.52). Moreover, NHBs had lower risk of being diagnosed with psychological issues (aHR = 0.71, 95% CI 0.63-0.80) but a higher risk for cognitive decline/dementia (aHR = 1.30, 95% CI 1.08-1.56). In conclusion, NHB women diagnosed with BC were less likely than NHW to undergo curative intent surgery or receive endocrine therapy, and had a higher risk of cognitive decline/dementia after cancer treatment. Public policy measures are urgently needed which equalize access to quality healthcare for all patients and that promote a learning healthcare system which can improve cancer outcomes.

Identification of Two Genetic Loci Associated with Leukopenia after Chemotherapy in Patients with Breast Cancer

PURPOSE

To identify molecular predictors of grade 3/4 neutropenic or leukopenic events (NLE) after chemotherapy using a genome-wide association study (GWAS).

EXPERIMENTAL DESIGN

A GWAS was performed on patients in the phase III chemotherapy study SUCCESS-A (n = 3,322). Genotyping was done using the Illumina HumanOmniExpress-12v1 array. Findings were functionally validated with cell culture models and the genotypes and gene expression of possible causative genes were correlated with clinical treatment response and prognostic outcomes.

RESULTS

One locus on chromosome 16 (rs4784750; NLRC5; P = 1.56E-8) and another locus on chromosome 13 (rs16972207; TNFSF13B; P = 3.42E-8) were identified at a genome-wide significance level. Functional validation revealed that expression of these two genes is altered by genotype-dependent and chemotherapy-dependent activity of two transcription factors. Genotypes also showed an association with disease-free survival in patients with an NLE.

CONCLUSIONS

Two loci in NLRC5 and TNFSF13B are associated with NLEs. The involvement of the MHC I regulator NLRC5 implies the possible involvement of immuno-oncological pathways.

Racial disparities in neutrophil counts among patients with metastatic breast cancer during treatment with CDK4/6 inhibitors

PURPOSE

The three CDK4/6 inhibitors (CDK4/6i) approved for use in HR-positive/HER2-negative metastatic breast cancer (MBC), palbociclib, ribociclib, and abemaciclib, are generally well tolerated; however, neutropenia is a common toxicity. Within the general population, neutropenia has been shown to be more common in individuals of African descent. The landmark CDK4/6i trials in MBC lacked racial diversity in their patient populations. We aimed to assess the toxicity profiles of CDK4/6is in a racially diverse population.

METHODS

We conducted a retrospective study at Montefiore Medical Center in patients with HR-positive/HER2-negative MBC prescribed CDK4/6i as first or subsequent line therapy between January 2015 and April 2020. Baseline characteristics and laboratory data at various treatment timepoints were collected.

RESULTS

The final analysis included 182 patients, of whom 46% were Black. Baseline absolute neutrophil count (ANC) was lower in the Black vs. Non-Black cohort (p = 0.001) but the change in ANC from baseline (delta-ANC) was smaller in the Black cohort, and the ANC at different treatment timepoints was similar between groups. There was no difference in the rate of infection or number of dose delays/reductions between racial groups. We did not find any difference in PFS between Black and Non-Black groups, regardless of the presence of CDK4/6i-induced neutropenia.

CONCLUSION

We analyzed toxicity profiles of 182 patients with HR-positive/HER2-negative MBC treated with CDK4/6i. Despite the lower baseline ANC seen in our Black cohort, treatment toxicities were similar between racial groups. Long-term outcomes with CDK4/6i therapy, measured by PFS, were similar between Black vs. Non-Black patients.

Racial disparity in taxane-induced neutropenia among cancer patients

BACKGROUND

Large interindividual variations have been reported in chemotherapy-induced toxicities. Little is known whether racial disparities exist in neutropenia associated with taxanes.

METHODS

Patients with a diagnosis of primary cancer who underwent chemotherapy with taxanes were identified from Vanderbilt University Medical Center's Synthetic Derivative. Multinomial regression models were applied to evaluate odds ratios (ORs) and 95% confidence intervals (CIs) of neutropenia associated with race, with adjustments for demographic variables, baseline neutrophil count, chemotherapy-related information, prior treatments, and cancer site.

RESULTS

A total of 3492 patients were included in the study. Compared with White patients, grade 2 or higher neutropenia was more frequently recorded among Black patients who received taxanes overall (42.2% vs. 32.7%, p < 0.001) or paclitaxel (43.0% vs. 36.7%, p < 0.001) but not among those who received docetaxel (32.0% vs. 30.2%, p = 0.821). After adjustments for multiple covariates, Black patients who received chemotherapy with any taxanes had significantly higher risk of grade 2 (OR = 1.53; 95% CI = 1.09-2.14) and grade 3 (OR = 1.91; 95% CI = 1.36-2.67) neutropenia but comparable risk of grade 4 neutropenia (OR = 1.19; 95% CI = 0.79-1.79). Similar association patterns were observed for Black patients who specifically received paclitaxel, but a null association was found for those treated with docetaxel.

CONCLUSION

Black cancer patients treated with taxanes for any cancer had a higher risk of neutropenia compared with their White counterparts, especially those who received paclitaxel. More research is needed to understand the mechanism(s) underlying this racial disparity in order to enhance the delivery of patient-centered oncology.

Symptom Experience, Management, and Outcomes According to Race and Social Determinants Including Genomics, Epigenomics, and Metabolomics (SEMOARS + GEM): an Explanatory Model for Breast Cancer Treatment Disparity

Even after controlling for stage, comorbidity, age, and insurance status, black women with breast cancer (BC) in the USA have the lowest 5-year survival as compared with all other races for stage-matched disease. One potential cause of this survival difference is the disparity in cancer treatment, evident in many population clinical trials. Specifically, during BC chemotherapy, black women receive less relative dose intensity with more dose reductions and early chemotherapy cessation compared with white women. Symptom incidence, cancer-related distress, and ineffective communication, including the disparity in patient-centeredness of care surrounding patient symptom reporting and clinician assessment, are important factors contributing to racial disparity in dose reduction and early therapy termination. We present an evidence-based overview and an explanatory model for racial disparity in the symptom experience during BC chemotherapy that may lead to a reduction in dose intensity and a subsequent disparity in outcomes. This explanatory model, the Symptom Experience, Management, Outcomes and Adherence according to Race and Social determinants + Genomics Epigenomics and Metabolomics (SEMOARS + GEM), considers essential factors such as social determinants of health, clinician communication, symptoms and symptom management, genomics, epigenomics, and pharmacologic metabolism as contributory factors.

The Impact of Age and Adjuvant Chemotherapy Modifications on Survival Among Black Women With Breast Cancer

BACKGROUND

Black women receive less relative dose intensity with more dose reductions and early chemotherapy cessation compared with White women. Adding further risk, older patients with breast cancer are most at risk for treatment modifications; however, it is unclear if this remains true for Black patients. Furthermore, the clinical implications of treatment modifications and delays on survival is uncertain, particularly in Black patients.

PATIENTS AND METHODS

The purpose was to investigate whether age was a moderator for the association between treatment modifications (dose held, dose delayed, and early cessation) and overall survival and disease-free survival (DFS) in Black women with breast cancer using a retrospective cohort study of patients with early stage breast cancer treated with adjuvant chemotherapy.

RESULTS

Across the entire sample (n = 115), 37.4% (n = 43) of patients experienced a treatment modification. There was a significant interaction between age group and held dose for DFS (P = .026). Specifically, those diagnosed at 55 years of age and older, who had doses of chemotherapy held, experienced worse DFS compared with those who did not (hazard ratio, 4.185; 95% confidence interval, 1.187-14.75). In contrast, there was no difference in DFS between those who did and did not have doses held in patients diagnosed below 55 years of age (hazard ratio, 0.626; 95% confidence interval, 0.177-2.218).

CONCLUSION

In this study, Black women receiving adjuvant chemotherapy for treatment of early stage breast cancer had roughly equal treatment modifications across age groups. However, held doses of chemotherapy in older Black patients were associated with worse DFS. Age may impact clinical outcomes seen with adjuvant chemotherapy treatment modifications.

The Duffy antigen receptor for chemokines, ACKR1,- 'Jeanne DARC' of benign neutropenia

Benign neutropenia, observed in different ethnic groups, is the most common form of neutropenia worldwide. A specific single nucleotide polymorphism, rs2814778, located at the promoter of the ACKR1 (previously termed DARC) gene, which disrupts a binding site for the GATA1 erythroid transcription factor, resulting in a ACKR1-null phenotype, was found to serve as a predictor of low white blood cell and neutrophil counts in African-Americans and Yemenite Jews. Individuals with benign neutropenia due to the ACKR1-null allele have been found to have an increased susceptibility to human immunodeficiency virus infection and, on the other hand, a protective effect against malaria. The associated protective effect may explain the spread of the ACKR1-null allele by natural selection. The reviewed relationships between ACKR1 polymorphism and various pathological states may have important clinical implications to individuals with and without benign neutropenia. Potential mechanisms for ACKR1 (previously termed DARC) modulation during neutrophil recruitment to inflammation, and chemokine bioavailability in the circulation and in local tissue are reviewed and discussed.

A stakeholder-informed randomized, controlled comparative effectiveness study of an order prescribing intervention to improve colony stimulating factor use for cancer patients receiving myelosuppressive chemotherapy: the TrACER study

Colony stimulating factors (CSF) are widely prescribed to avoid febrile neutropenia (FN) among cancer patients receiving chemotherapy, but studies show their use is often not consistent with practice guidelines. In addition, there is limited high quality evidence assessing benefits and harms of primary prophylactic-CSF (PP-CSF) in the setting of chemotherapy that poses an intermediate risk of FN. To address these issues, with funding from the Patient Centered Outcomes Research Institute (PCORI) and the National Cancer Institute's Community Oncology Research Program, SWOG is sponsoring a prospective, cluster randomized controlled pragmatic trial of an automated order entry protocol for PP-CSF among patients with breast, lung and colorectal cancer receiving myelosuppressive chemotherapy, with a nested randomized controlled trial of PP-CSF for patients receiving intermediate risk chemotherapy. Primary outcomes include adherence to practice guidelines, overall rates of FN and rates of FN among persons receiving intermediate risk chemotherapy. The study, the first pragmatic trial in the National Cancer Institute's cancer cooperative clinical trials network, will provide critical evidence to inform physician and patient decision-making around PP-CSF use and practice policies regarding automated orders in cancer components.

A cohort study of ethnic differences in use of adjuvant chemotherapy and radiation therapy for breast cancer in New Zealand

Background

Ethnic and socioeconomic inequities in use of breast cancer adjuvant therapy are well documented in many countries including the USA, and are known to contribute to lower breast cancer survival among minority ethnic and socioeconomically deprived women. We investigated ethnic and socioeconomic inequities in use of adjuvant radiotherapy and chemotherapy in a cohort of women with invasive breast cancer in New Zealand.

Methods

All women with newly diagnosed invasive breast cancer during 1999-2012 were identified from the Waikato Breast Cancer Register. Rates of chemotherapy use and radiotherapy use were assessed in women who were deemed to be eligible for chemotherapy (n = 1212) and radiotherapy (n = 1708) based on guidelines. Factors associated with use of chemotherapy and radiation therapy were analysed in univariate and multivariate regression models, adjusting for covariates.

Results

Overall, rates of chemotherapy and radiotherapy use were 69% (n = 836) and 87.3% (n = 1491), respectively. In the multivariate model, significantly lower rates of radiotherapy use were associated with Māori compared with NZ European (Odds Ratio [OR] = 0.63, 0.40-0.98), presence of comorbidity (OR = 0.49, 0.34-0.72), distance from hospital of over 100km (OR = 0.47, 0.23-0.96), mastectomy compared with breast conserving surgery (OR = 0.32, 0.17-0.56) and non-screen compared with screen detection (OR = 0.53, 0.35-0.79). No significant associations were observed between chemotherapy use and ethnic or socio-demographic factors.

Conclusions

Improving access for radiotherapy, especially for women who are at a higher risk of not receiving optimum cancer therapy due to ethnicity, geography or socioeconomic status need to be recognized as a priority to reduce inequities in breast cancer care in New Zealand.

Analysis of overall survival in a large multiethnic cohort reveals absolute neutrophil count of 1,100 as a novel prognostic cutoff in African Americans

Although absolute neutrophil counts (ANC) below 1.5x103/uL are used to define neutropenia as a marker of increased susceptibility to infections, their relationship with survival has not been examined. Since low counts trigger extensive investigations, determining prognostic cutoffs especially for different ethnicities and races is critical.A multiethnic cohort of 27,760 subjects, 65 years old and above, was utilized to evaluate the association of neutropenia with overall survival in different ethnicities and races.The mean ANC was 4.6±1.51x103/uL in non-Hispanic whites, 3.6±1.57x103/uL in non-Hispanic blacks and 4.3±1.54x103/uL in Hispanics (p<0.001). An ANC below 1.5x103/uL was associated with significantly shorter overall survival among whites (HR 1.74; 95% CI 1.18 - 2.58; p<0.001), but not in blacks (HR 0.89; 95% CI 0.86 - 1.17; p=0.40) or Hispanics (HR 1.04; 95% CI 0.76 - 1.46; p=0.82), after adjustment for age, sex, comorbidities, anemia and thrombocytopenia. Using Cox regression multivariable models, an ANC below 1.1x103/uL in blacks was found to be associated with increased mortality (HR 1.86; 95%CI 1.21 - 2.87; p<0.01). We found no association between neutropenia and mortality at any ANC cutoff in elderly Hispanics. In conclusion, neutropenia was found to be an independent prognostic variable in the elderly, when determined in race-specific manner. Most importantly, a cutoff of 1.1x103 neutrophils/uL may be a more prognostically relevant marker in elderly blacks and could serve as a novel threshold for further evaluation and intervention in this population.

Examining racial variation in antiemetic use and post-chemotherapy health care utilization for nausea and vomiting among breast cancer patients

PURPOSE

Racial minority cancer patients may experience underuse of antiemetic medications to prevent chemotherapy-induced nausea and vomiting (CINV). In addition to its adverse implications for quality of life, antiemetic underuse may contribute to observed disparities in acute illness during chemotherapy. To understand the potential contribution of CINV prophylaxis to breast cancer disparities, we assessed racial variation in potent antiemetic use and post-chemotherapy utilization related to CINV and the relationship between the two.

METHODS

We used SEER-Medicare data to evaluate the health care utilization in the 14 days following chemotherapy initiation among black and white women receiving highly emetogenic chemotherapy for breast cancer. We used modified Poisson regression to assess the relationship between (1) race and CINV-related utilization and (2) NK1 use and CINV-related utilization, overall and stratified by race. We report adjusted risk ratios (aRR) and 95 % confidence intervals (CI).

RESULTS

The study included 1130 women. Black women were 11 % less likely than white women to use neurokinin-1 receptor antagonists (NK1s) for CINV prophylaxis (p = 0.02); however, they experienced fewer CINV-related encounters following chemotherapy (unadjusted RR = 0.63, 95 %CI = 0.40-0.99; p = 0.05). After adjustment for clinical covariates, estimates were similar but no longer statistically significant (p = 0.07). Among white women, NK1 use was associated with increased CINV-related utilization (aRR NK1 users vs. non-users: 1.35, 95 % CI = 1.07-1.69, p = 0.01), likely resulting from unmeasured confounders.

CONCLUSION

Black women were less likely to use NK1s- and CINV-related services. Racial variation in CINV-related services use may be partly explained by differential symptom reporting or access to care.

African American Race is an Independent Risk Factor in Survival from Initially Diagnosed Localized Breast Cancer

BACKGROUND: African American race negatively impacts survival from localized breast cancer but co-variable factors confound the impact.

METHODS: Data sets were analyzed from the Surveillance, Epidemiology and End Results (SEER) directories from 1973 to 2011 consisting of patients with designated diagnosis of breast adenocarcinoma, race as White or Caucasian, Black or African American, Asian, American Indian or Alaskan Native, Native Hawaiian or Pacific Islander, age, stage I, II or III, grade 1, 2 or 3, estrogen receptor or progesterone receptor positive or negative, marital status as single, married, separated, divorced or widowed and laterality as right or left. The Cox Proportional Hazards Regression model was used to determine hazard ratios for survival. Chi square test was applied to determine the interdependence of variables found significant in the multivariable Cox Proportional Hazards Regression analysis. Cells with stratified data of patients with identical characteristics except African American or Caucasian race were compared.

RESULTS: Age, stage, grade, ER and PR status and marital status significantly co-varied with race and with each other. Stratifications by single co-variables demonstrated worse hazard ratios for survival for African Americans. Stratification by three and four co-variables demonstrated worse hazard ratios for survival for African Americans in most subgroupings with sufficient numbers of values. Differences in some subgroupings containing poor prognostic co-variables did not reach significance, suggesting that race effects may be partly overcome by additional poor prognostic indicators.

CONCLUSIONS: African American race is a poor prognostic indicator for survival from breast cancer independent of 6 associated co-variables with prognostic significance.

Prevalence of neutropenia in children by nationality

Background

A high prevalence of neutropenia has been reported in several ethnic groups amongst whom many healthy individuals with low neutrophil counts undergo unnecessary investigations. This study aims to ascertain the prevalence of neutropenia (NP) in a large cohort of children from North African, Middle Eastern, and Asian countries residing in the United Arab Emirates.

Methods

Neutrophil counts of 26,542 children (one day to six years of age) from 86 countries were analyzed. The subjects were enrolled in the Well-Child-Care program of Ambulatory Health Services of Emirate of Abu Dhabi, United Arab Emirates. NP was defined as a neutrophil count <1.5 × 10⁹/L and severe NP <0.5 × 10⁹/L.

Results

The neutrophil counts reached a nadir in the fourth week of life and changed slightly from the age of six-months to six-years. The frequency of NP was (from West-to-East): North African Arabs 15.4 %, Green Crescent Arabs 9.8 %, Peninsular Arabs 10.9 %, Iranians 3.1 %, Afghanis 2.5 %, Pakistanis 5.6 %, Indians 10.2 %, and Filipinos 7.3 %. The frequency of severe NP in North African Arabs (Sudanese) was 2.8 %, Green Crescent and Peninsular Arabs ≤1 %, Indians 1.5 %, and Filipinos 1.8 %. In 12,703 Emirati children, the frequency of NP was 10.6 % similar to their adult counterparts.

Conclusion

The prevalence of childhood NP varied considerably by geoethnicity. Measures to prevent the inappropriate investigations of healthy children with benign neutropenia are proposed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12878-016-0054-8) contains supplementary material, which is available to authorized users.

A perfect storm: How tumor biology, genomics, and health care delivery patterns collide to create a racial survival disparity in breast cancer and proposed interventions for change

It is well known that there is a significant racial divide in breast cancer incidence and mortality rates. African American women are less likely to be diagnosed with breast cancer than white women but are more likely to die from it. This review explores the factors that may contribute to the racial survival disparity. Consideration is paid to what is known about the role of differences in tumor biology, genomics, cancer screening, and quality of cancer care. It is argued that it is the collision of 2 forces, tumor biology and genomics, with patterns of care that leads to the breast cancer mortality gap. The delays, misuse, and underuse of treatment for African American patients are of increased significance when these patients are presenting with more aggressive forms of breast cancer. In the current climate of health care reform ushered in by the Affordable Care Act, this article also evaluates interventions to close the disparity gap. Prior interventions have been too narrowly focused on the patient rather than addressing the system and improving care across the continuum of breast cancer evaluation and treatment. Lastly, areas of future investigation and policy initiatives aimed at reducing the racial survival disparity in breast cancer are discussed.

The early discontinuation of palliative chemotherapy in older patients with cancer

PURPOSE

Older patients with cancer may have an increased risk of early discontinuation of active treatment (ED), which results in poor outcome in curative or adjuvant settings. We aimed to determine the association between survival and ED and to identify predictors of ED in palliative setting.

METHODS

Ninety-eight patients older than 65 years of age who received a comprehensive geriatric assessment (CGA) before palliative first-line chemotherapy were analyzed. Clinical information and CGA results were retrieved from electronic medical record. CGA included Charlson's co-morbidity index, activities of daily living (ADL), instrumental ADL (IADL), Mini-Mental Status Examination, short-form of the geriatric depression scale, timed-get-up-and-go test (TGUG), and mini-nutritional assessment (MNA). ED was defined as no active cancer treatment (radiotherapy and/or chemotherapy) beyond palliative first-line chemotherapy. Predictors of ED were identified using clinical parameters and CGA.

RESULTS

Active treatment was discontinued after first-line chemotherapy in 30 patients during median follow-up period of 15.1 months. ED after first-line chemotherapy was associated with shorter overall survival (OS; median OS = 3.1 vs. 14.7 months in patients with ED compared with patients without ED, p < 0.001). Eastern Cooperative Oncology Group performance status, living alone, ADL, IADL, MNA, and TGUG were associated with ED (p = 0.001, p = 0.048, p = 0.001, p < 0.001, p < 0.001, p = 0.002, respectively). In multivariable analysis, malnutrition and dependent IADL were the independent predictive factors for ED (odds ratio = 5.03; 95 % confidence interval = 1.50-16.87: odds ratio = 3.06; confidence interval = 1.03-9.12, respectively).

CONCLUSIONS

ED was associated with shorter OS in older patients with cancer. Malnutrition and dependent IADL were identified as independent predictive factors for ED.

Impact of obesity on cancer survivorship and the potential relevance of race and ethnicity

Evidence that obesity is associated with cancer incidence and mortality is compelling. By contrast, the role of obesity in cancer survival is less well understood. There is inconsistent support for the role of obesity in breast cancer survival, and evidence for other tumor sites is scant. The variability in findings may be due in part to comorbidities associated with obesity itself rather than with cancer, but it is also possible that obesity creates a physiological setting that meaningfully alters cancer treatment efficacy. In addition, the effects of obesity at diagnosis may be distinct from the effects of weight change after diagnosis. Obesity and related comorbid conditions may also increase risk for common adverse treatment effects, including breast cancer-related lymphedema, fatigue, poor health-related quality of life, and worse functional health. Racial and ethnic groups with worse cancer survival outcomes are also the groups for whom obesity and related comorbidities are more prevalent, but findings from the few studies that have addressed these complexities are inconsistent. We outline a broad theoretical framework for future research to clarify the specifics of the biological-social-environmental feedback loop for the combined and independent contributions of race, comorbid conditions, and obesity on cancer survival and adverse treatment effects. If upstream issues related to comorbidities, race, and ethnicity partly explain the purported link between obesity and cancer survival outcomes, these factors should be among those on which interventions are focused to reduce the burden of cancer.

Disparities in breast cancer treatment and outcomes: biological, social, and health system determinants and opportunities for research

Racial disparities in breast cancer mortality have been widely documented for several decades and persist despite advances in receipt of mammography across racial groups. This persistence leads to questions about the roles of biological, social, and health system determinants of poor outcomes. Cancer outcomes are a function not only of innate biological factors but also of modifiable characteristics of individual behavior and decision making as well as characteristics of patient-health system interaction and the health system itself. Attempts to explain persistent racial disparities have mostly been limited to discussion of differences in insurance coverage, socioeconomic status, tumor stage at diagnosis, comorbidity, and molecular subtype of the tumor. This article summarizes existing literature exploring reasons for racial disparities in breast cancer mortality, with an emphasis on treatment disparities and opportunities for future research. Because breast cancer care requires a high degree of multidisciplinary team collaboration, ensuring that guideline recommended treatment (such as endocrine therapy for hormone receptor positive patients) is received by all racial/ethnic groups is critical and requires coordination across multiple providers and health care settings. Recognition that variation in cancer care quality may be correlated with race (and socioeconomic and health system factors) may assist policy makers in identifying strategies to more equally distribute clinical expertise and health infrastructure across multiple user populations.

Appropriate chemotherapy dosing for obese adult patients with cancer: American Society of Clinical Oncology clinical practice guideline

PURPOSE

To provide recommendations for appropriate cytotoxic chemotherapy dosing for obese adult patients with cancer.

METHODS

The American Society of Clinical Oncology convened a Panel of experts in medical and gynecologic oncology, clinical pharmacology, pharmacokinetics and pharmacogenetics, and biostatistics and a patient representative. MEDLINE searches identified studies published in English between 1996 and 2010, and a systematic review of the literature was conducted. A majority of studies involved breast, ovarian, colon, and lung cancers. This guideline does not address dosing for novel targeted agents.

RESULTS

Practice pattern studies demonstrate that up to 40% of obese patients receive limited chemotherapy doses that are not based on actual body weight. Concerns about toxicity or overdosing in obese patients with cancer, based on the use of actual body weight, are unfounded.

RECOMMENDATIONS

The Panel recommends that full weight-based cytotoxic chemotherapy doses be used to treat obese patients with cancer, particularly when the goal of treatment is cure. There is no evidence that short- or long-term toxicity is increased among obese patients receiving full weight-based doses. Most data indicate that myelosuppression is the same or less pronounced among the obese than the non-obese who are administered full weight-based doses. Clinicians should respond to all treatment-related toxicities in obese patients in the same ways they do for non-obese patients. The use of fixed-dose chemotherapy is rarely justified, but the Panel does recommend fixed dosing for a few select agents. The Panel recommends further research into the role of pharmacokinetics and pharmacogenetics to guide appropriate dosing of obese patients with cancer.

Do racial or socioeconomic disparities exist in lung cancer treatment?

BACKGROUND

Determine the effects of race, socioeconomic status, and treatment on outcomes for patients diagnosed with lung cancer.

METHODS

The Florida cancer registry and inpatient and ambulatory data were queried for patients diagnosed from 1998-2002.

RESULTS

A total 76,086 of lung cancer patients were identified. Overall, 55.6% were male and 44.4% were female. The demographic distribution of patients was 92.7% Caucasian, 6.7% African American, and 5.7% Hispanic. The mean age of diagnosis was 70 years old. African American patients presented at a younger age, with more advanced disease, and were less likely to undergo surgical therapy than their Caucasian counterparts. Median survival time (MST) for the entire cohort was 8.7 months, while MST for African American patients was 7.5 months. Patients who received surgery, chemotherapy, or radiation therapy demonstrated significantly improved outcomes. Stepwise multivariate analysis revealed that African American race was no longer a statistically significant predictor of worse outcomes once corrections were made for demographics and comorbid conditions, suggesting that the originally reported disparities in lung cancer outcomes and race may be in part because of poor pretreatment performance status. In contrast, patients of the lowest socioeconomic status continue to have a slightly worse overall prognosis than their affluent counterparts (hazard ratio = 1.05, P = .001).

CONCLUSIONS

Lung cancer continues to carry a poor prognosis for all patients. Once comorbidities are corrected for, African American patients carry equivalently poor outcomes. Nonetheless, emphasis must be placed on improving pretreatment performance status among African American patients and efforts for earlier diagnosis among the impoverished patients must be made.

Racial and socioeconomic disparities in adjuvant chemotherapy for older women with lymph node-positive, operable breast cancer

BACKGROUND

Consistent with findings from clinical trials, a recent population-based study indicated that adjuvant chemotherapy for lymph node-positive, operable breast cancer is effective at improving survival in older women, specifically those ages 65 years to 69 years; however, to the authors' knowledge, no conclusion has been reached about the relative benefit of chemotherapy for women aged > or =70 years, probably because of small number of patients. However, little is known about racial and socioeconomic disparities in adjuvant chemotherapy for breast cancer among older women.

METHODS

This study included 14,177 white women and 1277 black women aged > or =65 years who were diagnosed with operable breast cancer (stage II-IIIA) and positive lymph nodes between 1991 and 2002. These women were identified from the Surveillance, Epidemiology, and End Results and Medicare-linked database. Multivariate logistic regression was used to compute the odds ratios of receiving chemotherapy among black women compared with white women, and the causal step approach was used to test whether census tract-level poverty mediated racial disparities.

RESULTS

Interaction terms analyses indicated that regressions should be stratified by age group. In the group ages 65 years to 69 years, the adjusted odds ratio of receiving chemotherapy were lower for black women than for white women (odds ratio, 0.85; 95% confidence interval, 0.57-0.97). Poverty mediated the association between chemotherapy and race in this age group. No racial or socioeconomic disparities were observed among women aged > or =70 years.

CONCLUSIONS

This study documented racial disparities in adjuvant chemotherapy that were mediated by poverty in women ages 65 years to 69 years, an age group for which there is clear evidence for the efficacy of chemotherapy, but no disparities were observed among women aged > or =70 years. The authors concluded that it is important to work toward reducing treatment disparities among older women.

Host genetic variants in the interleukin-6 promoter predict poor outcome in patients with estrogen receptor-positive, node-positive breast cancer

Interleukin-6 modulates immune response, estrogen production, and growth pathways in breast cancer. We evaluated the effect of several common, functional interleukin-6 promoter variants in node-positive breast cancer patients enrolled on a multicenter, cooperative group, adjuvant chemotherapy trial to determine whether these variants were associated with clinical outcome overall and by estrogen receptor tumor phenotype. Genomic DNA and clinical data were collected from a clinical trial of adjuvant anthracycline-based chemotherapy followed by randomization to high-dose cyclophosphamide/thiotepa or observation (Intergroup Trial 0121). Genotyping for -174G>C (rs1800795), -597G>A (rs1800797), and -572G>C (rs1800796) was done by site-specific PCR and PyroSequencing, whereas the -373A(n)T(n) repeat was directly sequenced. Log-rank tests and Cox modeling were used to compare outcomes by genotype/haplotype and other factors. Three hundred forty-six patients (64% of trial) had corresponding genotype/clinical data available and did not differ from overall trial participants. After adjustment, patients with estrogen receptor-positive tumors and genotypes 597 GG or 174 GG had significantly worse disease-free survival [hazard ratio (HR), 1.6; P = 0.02 and HR, 1.71; P = 0.007, respectively], whereas the 373 8A12T repeat appeared to be protective (HR, 0.62; P = 0.02). The presence of at least one copy of the haplotype ([-597G, -572G, -373[10A/11T], -174G]) was associated with worse disease-free survival (HR, 1.46; P = 0.04). Kaplan-Meier plots show that all patients in this group relapsed by 24 months from diagnosis. This poor-risk haplotype was quite common overall (estimated frequency, 0.20) and twice as frequent among Blacks (estimated frequency, 0.41).

Prevalence, phenotype and inheritance of benign neutropenia in Arabs

Background

Benign neutropenia, i.e., neutropenia not associated with an increased risk of infection, may result in serious medical consequences when a 'standard' definition of neutropenia (absolute neutrophil count (ANC) < 1.5 × 10⁹cells/L) is universally applied to all races. The aims of this study were to determine the prevalence of benign neutropenia among healthy Arabs and evaluate its mode of inheritance.

Methods

ANCs were studied prospectively amongst a healthy indigenous population (n = 1032) from the United Arab Emirates undergoing a nation-wide sickle-cell and thalassemia screening program. The mean neutrophil count and the prevalence of benign neutropenia were compared by age, sex and amongst various tribes.

Results

The mean neutrophil count (× 10⁹cells/L) was 3.3 (range 0.95–7.6). Benign neutropenia was present in 110 (10.7%) subjects of whom 24 (2.3%) individuals had moderate neutropenia (ANC 0.5 – 1.0 × 10⁹ cells/L). In the 22 tribe-family groups, the prevalence of benign neutropenia varied between 0% and 38%. Benign neutropenia showed no difference in the frequency amongst the sexes (p = 0.23) and it was independent of age (Spearman's rho = 0.05, p = 0.13). The age-related mean neutrophil count was the lowest in Arabs when compared with other ethnic groups (Blacks, Europeans and Mexicans). The inheritance of benign neutropenia was consistent with an autosomal dominant pattern; however, the diversity of observed phenotypes suggested the presence of more than one genetic variant for this trait.

Conclusion

Arabs have a high prevalence of benign neutropenia that may be inherited as an autosomal dominant trait.

Differences in breast carcinoma characteristics in newly diagnosed African–American and Caucasian patients

BACKGROUND

Breast carcinomas in African-American patients appear to be more aggressive than in Caucasian patients due to multifactorial differences.

METHODS

The authors compiled pathology data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database regarding stage, histologic grade, and estrogen receptor (ER) expression in breast carcinomas diagnosed in 197,274 African-American and Caucasian patients between 1990 and 2000, and the same information, along with nuclear grade, Ki-67, c-erb-B2, and p53 expression, in 2230 African-American and Caucasian patients diagnosed at Thomas Jefferson University Hospital between 1995 and 2002. Immunohistochemical markers were assayed in paraffin-embedded, formalin-fixed tissue stained with hematoxylin and eosin using antibodies to these proteins, with differences in expression analyzed by the chisquare test.

RESULTS

In both databases, more African-American patients presented with advanced stage tumors and higher histologic (P < .001) and nuclear grade (P < .001) than Caucasian patients. African-American patients had less ER positivity (51.9% vs 63.1%; P < .001) but significantly higher Ki-67 (42.4% vs 28.7%; P < .001) and p53 expression (19.4% vs 13.1%; P < .05) than Caucasian patients with all stages of disease. In addition, the basal or "triple-negative" breast cancer phenotype was more common in African-American patients than in Caucasian patients (20.8% vs 10.4%; P < .0001), and was associated with higher histologic and nuclear grade (P < .0001).

CONCLUSIONS

African-American patients with breast carcinomas are more likely than Caucasian patients to present with tumors that are of a later stage and higher grade, with higher Ki-67 expression and more ER negativity, thereby highlighting a greater need for early screening among African-American women. Molecular studies that may explain these differences, and correlations with survival, have been proposed to identify therapeutic targets.

Effect of patient socioeconomic status and body mass index on the quality of breast cancer adjuvant chemotherapy

PURPOSE

The purpose of this study was to investigate the relationship between socioeconomic status (SES) and the use of intentionally reduced doses of chemotherapy in the adjuvant treatment of breast cancer.

PATIENTS AND METHODS

Patients with breast cancer treated with a standard chemotherapy regimen (n = 764) were enrolled in a prospective registry after signing informed consent. Detailed information was collected on patient, disease, and treatment, including chemotherapy doses. Zip code level data on median household income, proportion of people living below the poverty level, and educational attainment were obtained from the US Census. Doses for the first cycle of chemotherapy lower than 85% of standard were considered to be reduced. Univariate analyses and multivariate logistic regression were performed to identify factors associated with the use of reduced first cycle doses.

RESULTS

In univariate analysis, individual education attainment, zip code SES measures, body mass index, and geographic region were all significantly associated with receipt of intentionally reduced doses of chemotherapy. In multivariate analysis, controlling for geography, factors independently associated with reduced doses were obesity (odds ratio [OR], 2.47; 95% CI, 1.36 to 4.51), severe obesity (OR, 4.04; 95% CI, 1.46 to 11.19), and education less than high school (OR, 3.07; 95% CI, 1.57 to 5.99).

CONCLUSION

Social disparities in breast cancer outcomes may be in part the result of lower quality chemotherapy doses in the adjuvant treatment of breast cancer. Efforts to address such prescribing patterns may help reduce SES disparities in breast cancer survival.

A review of the ethnic differences in breast cancer

Women of African descent have a lower incidence of breast cancer than their white counterparts; however, the overall age-adjusted breast cancer mortality rates are higher. They also present at a younger age, and have more advanced disease that exhibits poor prognostic features including significantly larger tumors of higher grade, higher rates of estrogen receptor and progesterone receptor negativity and a higher rate of p53 mutations and HRAS1 proto-oncogene expression, all of which confer a poor prognosis. While there are many possible contributory factors to the discrepancies in outcome in women of African descent, there is no satisfactory explanation as to why women of African origin tend to present at a younger age with hormone receptor-negative tumors and more adverse prognostic features.