Factors affecting survival among women with breast cancer in Hawaii

Differences in Breast Cancer Subtypes among Racial/Ethnic Groups

BACKGROUND

Differences in the incidence of breast cancer subtypes among racial/ethnic groups have been evaluated as a contributing factor in disparities seen in breast cancer prognosis. We evaluated new breast cancer cases in Hawai'i to determine if there were subtype differences according to race/ethnicity that may contribute to known disparities.

METHODS

We reviewed 4591 cases of women diagnosed with breast cancer from two large tumor registries between 2015 and 2022. We evaluated breast cancer cases according to age at diagnosis, self-reported race, breast cancer subtype (ER, PR, and HER2 receptor status), histology, county, and year.

RESULTS

We found both premenopausal and postmenopausal Native Hawaiian women were less likely to be diagnosed with triple-negative breast cancer (OR = 0.26, 95% CI 0.12-0.58 p = 0.001; OR = 0.54, 95% CI 0.36, 0.80 p = 0.002, respectively).

CONCLUSIONS

The results of our study support that there are racial/ethnic differences in breast cancer subtypes among our population, which may contribute to differences in outcomes. Further evaluation of clinical and pathological features in each breast cancer subtype may help improve the understanding of outcome disparities seen among different racial/ethnic groups.

Higher 10-Year Survival with Breast-Conserving Therapy over Mastectomy for Women with Early-Stage (I-II) Breast Cancer: Analysis of the CDC Patterns of Care Data Base

Background

Studies in the United States are scarce that assess the survival differences between breast-conserving surgery plus radiation (Breast-Conserving Therapy; BCT) and mastectomy groups using population-based data while accounting for sociodemographic and clinical factors that affect the survival of women with early-stage breast cancer (ESBC).

Objective

To assess whether BCT provides superior long-term overall survival (OS) and breast cancer-specific survival (BCSS) compared with mastectomy in women with ESBC, while considering key factors that impact survival.

Design

Cohort study.

Methods

We analyzed data on women aged 20 years and older diagnosed with stage I-II breast cancer (BC) in 2004 who received either BCT or mastectomy. The data were collected by 5 state cancer registries through the Centers for Disease Control and Prevention-funded Patterns of Care study. Multivariable Cox proportional hazard models, accounting for sociodemographic and clinical factors, were used to calculate hazard ratios (HRs) with 95% confidence intervals (CI). Sensitivity analysis involved optimal caliper propensity score (PS) matching to address residual confounding.

Results

Of the 3495 women, 41.5% underwent mastectomy. The 10-year OS and BCSS were 82.7% and 91.1% for BCT and 72.3% and 85.7% for mastectomy, respectively. Adjusted models showed that mastectomy recipients had a 22% higher risk of all-cause deaths (ACD) (HR = 1.22, 95% CI = [1.06, 1.41]) and a 26% higher risk of breast cancer-specific deaths (BCD) (HR = 1.26, 95% CI = [1.02, 1.55]) than BCT recipients. Sensitivity analysis demonstrated that mastectomy was associated with a higher risk of ACD (P < .05) but did not exhibit a statistically significant risk for BCD. Women with HR+/HER2+ (luminal B) or invasive ductal carcinoma BC who underwent mastectomy had higher risks of ACD and BCD compared with BCT recipients, while the hazards for ACD in triple-negative BC did not remain significant after adjusting for covariates.

Conclusion

ESBC BCT recipients demonstrate superior OS and BCSS compared with mastectomy recipients.

Assessing the survival time of women with breast cancer in Northwestern Ethiopia: using the Bayesian approach

BACKGROUND

Despite the significant weight of difficulty, Ethiopia's survival rate and mortality predictors have not yet been identified. Finding out what influences outpatient breast cancer patients' survival time was the major goal of this study.

METHODS

A retrospective study was conducted on outpatients with breast cancer. In order to accomplish the goal, 382 outpatients with breast cancer were included in the study using information obtained from the medical records of patients registered at the University of Gondar referral hospital in Gondar, Ethiopia, between May 15, 2016, and May 15, 2020. In order to compare survival functions, Kaplan-Meier plots and the log-rank test were used. The Cox-PH model and Bayesian parametric survival models were then used to examine the survival time of breast cancer outpatients. The use of integrated layered Laplace approximation techniques has been made.

RESULTS

The study included 382 outpatients with breast cancer in total, and 148 (38.7%) patients died. 42 months was the estimated median patient survival time. The Bayesian Weibull accelerated failure time model was determined to be suitable using model selection criteria. Stage, grade 2, 3, and 4, co-morbid, histological type, FIGO stage, chemotherapy, metastatic number 1, 2, and >=3, and tumour size all have a sizable impact on the survival time of outpatients with breast cancer, according to the results of this model. The breast cancer outpatient survival time was correctly predicted by the Bayesian Weibull accelerated failure time model.

CONCLUSIONS

Compared to high- and middle-income countries, the overall survival rate was lower. Notable variables influencing the length of survival following a breast cancer diagnosis were weight loss, invasive medullar histology, comorbid disease, a large tumour size, an increase in metastases, an increase in the International Federation of Gynaecologists and Obstetricians stage, an increase in grade, lymphatic vascular space invasion, positive regional nodes, and late stages of cancer. The authors advise that it is preferable to increase the number of early screening programmes and treatment centres for breast cancer and to work with the public media to raise knowledge of the disease's prevention, screening, and treatment choices.

Pancreatic cancer among Pacific Islanders: a comprehensive analysis of an understudied racial group

OBJECTIVE

Racial disparities in care and outcome have been demonstrated for several cancers, but it is not clear that a similar discrepancy exists for pancreatic cancer. Furthermore, there are limited data describing the pancreatic cancer experience of Pacific Islanders. The primary objective of this study was to analyze the clinical characteristics, treatment, and outcomes of Pacific Islander patients with pancreatic cancer.

DESIGN

We obtained data for a consecutive sample of pancreatic adenocarcinoma patients who presented to the largest hospital in Hawaii from 1 January 2000, through 31 December 2019. Analyses were performed for the entire population and separately for patients who had their cancer resected. Overall survival was calculated by the Kaplan-Meier method. Cox proportional hazards regression models were constructed to determine the prognostic capacity of clinical and pathologic factors.

RESULTS

A total of 1040 patients were included in the final analysis. Pacific islanders presented at a significantly younger age compared to Whites or Asians and had the highest Medicaid rate. There were no statistically significant racial differences in stage at presentation or treatments. We did not demonstrate an association between race and survival on univariate analysis, nor after adjusting for demographic and tumor factors. Age, stage, and treatment were significantly associated with survival for both univariate and multivariate analyses.

CONCLUSION

We did not demonstrate disparate outcomes among Pacific Islanders with pancreatic cancer. This is likely due in part to the absence of a screening test and the notable poor prognosis of pancreatic adenocarcinoma. Furthermore, equity in treatment may have contributed to racial parity in survival.

Postdiagnosis body fatness, weight change and breast cancer prognosis: Global Cancer Update Program (CUP global) systematic literature review and meta-analysis

Previous evidence on postdiagnosis body fatness and mortality after breast cancer was graded as limited-suggestive. To evaluate the evidence on body mass index (BMI), waist circumference, waist-hip-ratio and weight change in relation to breast cancer prognosis, an updated systematic review was conducted. PubMed and Embase were searched for relevant studies published up to 31 October, 2021. Random-effects meta-analyses were conducted to estimate summary relative risks (RRs). The evidence was judged by an independent Expert Panel using pre-defined grading criteria. One randomized controlled trial and 225 observational studies were reviewed (220 publications). There was strong evidence (likelihood of causality: probable) that higher postdiagnosis BMI was associated with increased all-cause mortality (64 studies, 32 507 deaths), breast cancer-specific mortality (39 studies, 14 106 deaths) and second primary breast cancer (11 studies, 5248 events). The respective summary RRs and 95% confidence intervals per 5 kg/m2 BMI were 1.07 (1.05-1.10), 1.10 (1.06-1.14) and 1.14 (1.04-1.26), with high between-study heterogeneity (I2  = 56%, 60%, 66%), but generally consistent positive associations. Positive associations were also observed for waist circumference, waist-hip-ratio and all-cause and breast cancer-specific mortality. There was limited-suggestive evidence that postdiagnosis BMI was associated with higher risk of recurrence, nonbreast cancer deaths and cardiovascular deaths. The evidence for postdiagnosis (unexplained) weight or BMI change and all outcomes was graded as limited-no conclusion. The RCT showed potential beneficial effect of intentional weight loss on disease-free-survival, but more intervention trials and well-designed observational studies in diverse populations are needed to elucidate the impact of body composition and their changes on breast cancer outcomes.

Mortality rate and predictors among patients with breast cancer at a referral hospital in northwest Ethiopia: A retrospective follow-up study

BACKGROUND

Breast cancer is one of the common global health concerns that affects2.1 million women each year and causes the highest number of cancer-related morbidity and mortality among women. The objective of this study was to determine the mortality rate and its predictors among breast cancer patients at the referral hospitals, in northwest Ethiopia.

METHODS

A retrospective follow-up study was conducted on breast cancer patients registered between February 01, 2015 and February 28, 2018. They were selected by simple random sampling using computer-generated method and followed until February 29, 2020, in Amhara region referral hospital. A pre-tested data extraction checklist was used to collect data from the registration book and patient medical records. The collected data were entered into Epi-Data version 3.1 and exported to STATA version 14 for analysis. The mortality rate by person-year observation was computed. The Kaplan-Meier survival curve with the log-rank test was used to estimate the survival probabilities of the patients. Bivariate and multivariate Cox regression model was used to identify predictors of mortality.

RESULTS

The overall mortality rate of breast cancer was 16.9 per 100 person-years observation. The median survival time was 38.3 (IQR: 26.23, 49.4) months. Independent predictors of breast cancer mortality was; Clinical stage IV and stage III (aHR:10.44,95% CI: 8.02,11.93 and aHR: 9.43, 95% CI: 6.29,11.03respectively), number of positive lymph node in the category of 10 and more and number of positive lymph node within the category of 4-9 (aHR:12.58, 95%CI: 5.2, 30.46 and aHR: 4.78, 95% CI: 2.19, 10.43respectively), co-morbidities (aHR:1.5, 95%CI: 1.01,2.21), Postmenopausal (aHR:2.03,95% CI: 1.37, 3), histologic grade III (aHR:2.12, 95% CI: 1.26,3.55) and not received hormonal therapy (aHR: 2.19, 95%CI: 1.52,3.15) were independent predictors of mortality.

CONCLUSION

The overall mortality rate was 16.9 per 100 person-years. The finding was higher compared to high-income countries. Advanced clinical stage, co-morbidities, menopausal status, and hormonal therapy are the significant predictors of mortality. Early detection and treatment of breast cancer is needed to reduce the mortality rate.

Survival and predictors of breast cancer mortality in South Ethiopia: A retrospective cohort study

BACKGROUND

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in over 100 countries. In March 2021, the World Health Organization called on the global community to decrease mortality by 2.5% per year. Despite the high burden of the disease, the survival status and the predictors for mortality are not yet fully determined in many countries in Sub-Saharan Africa, including Ethiopia. Here, we report the survival status and predictors of mortality among breast cancer patients in South Ethiopia as crucial baseline data to be used for the design and monitoring of interventions to improve early detection, diagnosis, and treatment capacity.

METHODS

A hospital-based retrospective cohort study was conducted among 302 female breast cancer patients diagnosed from 2013 to 2018 by reviewing their medical records and telephone interviews. The median survival time was estimated using the Kaplan-Meier survival analysis method. A log-rank test was used to compare the observed differences in survival time among different groups. The Cox proportional hazards regression model was used to identify predictors of mortality. Results are presented using the crude and adjusted as hazard ratios along with their corresponding 95% confidence intervals. Sensitivity analysis was performed with the assumption that loss to follow-up patients might die 3 months after the last hospital visit.

RESULTS

The study participants were followed for a total of 4,685.62 person-months. The median survival time was 50.81 months, which declined to 30.57 months in the worst-case analysis. About 83.4% of patients had advanced-stage disease at presentation. The overall survival probability of patients at two and three years was 73.2% and 63.0% respectively. Independent predictors of mortality were: patients residing in rural areas (adjusted hazard ratio = 2.71, 95% CI: 1.44, 5.09), travel time to a health facility ≥7 hours (adjusted hazard ratio = 3.42, 95% CI: 1.05, 11.10), those who presented within 7-23 months after the onset of symptoms (adjusted hazard ratio = 2.63, 95% CI: 1.22, 5.64), those who presented more than 23 months after the onset of symptoms (adjusted hazard ratio = 2.37, 95% CI: 1.00, 5.59), advanced stage at presentation (adjusted hazard ratio = 3.01, 95% CI: 1.05, 8.59), and patients who never received chemotherapy (adjusted hazard ratio = 6.69, 95% CI: 2.20, 20.30).

CONCLUSION

Beyond three years after diagnosis, patients from southern Ethiopia had a survival rate of less than 60% despite treatment at a tertiary health facility. It is imperative to improve the early detection, diagnosis, and treatment capacities for breast cancer patients to prevent premature death in these women.

The obesity paradox in early and advanced HER2 positive breast cancer: pooled analysis of clinical trial data

While many studies have evaluated the relationship between BMI and breast cancer outcomes, it is unclear whether this relationship is consistent between early breast cancer (BC) and advanced BC. The study included 5099 patients with HER2 positive early BC (EBC) and 3496 with HER2 positive advanced BC (ABC). In the EBC cohort, higher BMI was associated with worse overall survival (OS) (HR [95% CI]: overweight = 1.30 [1.13-1.51]; obese = 1.37 [1.14-1.64], P = < 0.001), and worse disease-free survival (overweight = 1.10 [0.98-1.24]; obese = 1.20 [1.04-1.39], P = 0.061). In contrast, for the ABC cohort, higher BMI was significantly associated with improved OS (overweight = 0.85 [0.76-0.96]; obese = 0.82 [0.72-0.95], P = 0.014), and progression-free survival (overweight = 0.91 [0.83-1.01]; obese = 0.87 [0.77-0.98], P = 0.034). In this large high-quality dataset, higher BMI was independently associated with worse survival in EBC, paradoxically in ABC higher BMI was independently associated with improved survival.

Association of Obesity With Survival Outcomes in Patients With Cancer: A Systematic Review and Meta-analysis

Importance

Obesity, defined as a body mass index (BMI) greater than 30, is associated with a significant increase in the risk of many cancers and in overall mortality. However, various studies have suggested that patients with cancer and no obesity (ie, BMI 20-25) have worse outcomes than patients with obesity.

Objective

To assess the association between obesity and outcomes after a diagnosis of cancer.

Data Sources

PubMed, the Cochrane Library, and EMBASE were searched from inception to January 2020.

Study Selection

Studies reporting prognosis of patients with obesity using standard BMI categories and cancer were included. Studies that used nonstandard BMI categories, that were limited to children, or that were limited to patients with hematological malignant neoplasms were excluded. Screening was performed independently by multiple reviewers. Among 1892 retrieved studies, 203 (17%) met inclusion criteria for initial evaluation.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were reporting guideline was followed. Data were extracted by multiple independent reviewers. Risk of death, cancer-specific mortality, and recurrence were pooled to provide an adjusted hazard ratio (HR) with a 95% CI . A random-effects model was used for the retrospective nature of studies.

Main Outcomes and Measures

The primary outcome of the study was overall survival (OS) in patients with cancer, with and without obesity. Secondary end points were cancer-specific survival (CSS) and progression-free survival (PFS) or disease-free survival (DFS). The risk of events was reported as HRs with 95% CIs, with an HR greater than 1 associated with a worse outcome among patients with obesity vs those without.

Results

A total of 203 studies with 6 320 365 participants evaluated the association of OS, CSS, and/or PFS or DFS with obesity in patients with cancer. Overall, obesity was associated with a reduced OS (HR, 1.14; 95% CI, 1.09-1.19; P < .001) and CSS (HR, 1.17; 95% CI, 1.12-1.23; P < .001). Patients were also at increased risk of recurrence (HR, 1.13; 95% CI, 1.07-1.19; P < .001). Conversely, patients with obesity and lung cancer, renal cell carcinoma, or melanoma had better survival outcomes compared with patients without obesity and the same cancer (lung: HR, 0.86; 95% CI, 0.76-0.98; P = .02; renal cell: HR, 0.74; 95% CI, 0.53-0.89; P = .02; melanoma: HR, 0.74; 95% CI, 0.57-0.96; P < .001).

Conclusions and Relevance

In this study, obesity was associated with greater mortality overall in patients with cancer. However, patients with obesity and lung cancer, renal cell carcinoma, and melanoma had a lower risk of death than patients with the same cancers without obesity. Weight-reducing strategies may represent effective measures for reducing mortality in these patients.

Time to Adjuvant Chemotherapy and Its Predictors Among Women with Breast Cancer at the University of Gondar Compressive Specialized Hospital: A Retrospective Follow-Up Study

BACKGROUND

Early adjuvant chemotherapy improves the outcomes of breast cancer patients by increasing the benefit provided by the cytotoxic systemic therapies. Despite these, the recommended time to adjuvant chemotherapy and its predictors is very limited. Therefore, this study was determining the time to adjuvant chemotherapy and its predictors among women with breast cancer at the University of Gondar Comprehensive Specialized Hospital.

METHODS

An institution-based retrospective follow-up study was conducted at the University of Gondar Compressive Specialized Hospital from January 2015 to February 2019 among all women with breast cancer. Stata version 14 was used for data analysis. A stratified Cox regression model was fitted to identify the potential predictors. The adjusted hazard ratio (AHR) with a 95% confidence interval (CI) was reported to show the strength of the association. Cox-Snell residual test was used to check the goodness of fit.

RESULTS

In this study, the median time to adjuvant chemotherapy was 67 days with an interquartile range of 34-102 days. More than three-fourth (79.9%) of patients received chemotherapy after 30 days. Of the total, 96.6% of patients with co-morbidity received adjuvant chemotherapy after 30 days. Regarding surgical complications, 97.0% of the patients with a surgical complications were received adjuvant chemotherapy after 30 days. Older patients (AHR= 0.34, 95% CI: 0.16,0.71), presence of co-morbidity (AHR= 0.43, 95% CI: 0.29, 0.62), positive surgical margin (AHR= 0.40, 95% CI: 0.25, 0.64), and presence of surgical complication (AHR= 0.55, 95% CI: 0.34, 0.88) were significantly associated with delayed time to adjuvant chemotherapy.

CONCLUSION

In this study, time to adjuvant chemotherapy among women was longer. Age, co-morbidity, surgical complications, and margin status were significant predictors of time to adjuvant chemotherapy. Close follow-up is important for women with surgical complications, co-morbidities, elder patients, and patients with a positive margin.

Literature review of data-based models for identification of factors associated with racial disparities in breast cancer mortality

In the United States, early detection methods have contributed to the reduction of overall breast cancer mortality but this pattern has not been observed uniformly across all racial groups. A vast body of research literature shows a set of health care, socio-economic, biological, physical, and behavioural factors influencing the mortality disparity. In this paper, we review the modelling frameworks, statistical tests, and databases used in understanding influential factors, and we discuss the factors documented in the modelling literature. Our findings suggest that disparities research relies on conventional modelling and statistical tools for quantitative analysis, and there exist opportunities to implement data-based modelling frameworks for (1) exploring mechanisms triggering disparities, (2) increasing the collection of behavioural data, and (3) monitoring factors associated with the mortality disparity across time.

Modified metabolic syndrome and second cancers in women: A case control study

Background:

According to some studies, the metabolic syndrome causes diverse primary cancers; however, there is no evidence about metabolic syndrome impact on second cancers development in women.

Aim:

To find out the implication of the modified metabolic syndrome in women with second cancers.

Materials and Methods:

This was a case–control study, at a general hospital in Mexico City, in women with second cancers (cases) and age-matched women with only one neoplasm (controls). The analysis comprised: Tumor (s), anthropometric features, and body mass index (BMI); moreover, presence of diabetes mellitus, hypertension, and fasting serum levels of total cholesterol, triglycerides and glucose.

Results:

The sample was of nine cases and 27 controls. In cases, the metabolic syndrome (diabetes mellitus or glucose > 99 mg/dL + hypertension or blood pressure ≥ 135/85 mm Hg + triglycerides > 149 mg/dL or BMI ≥ 30 kg/m²) was more frequent (odds ratio 20.8, 95% confidence interval: 1.9–227.1).

Conclusion:

Our results suggest that in women, the modified metabolic syndrome may be a risk factor for second cancers.

Elevated expression of chemokine C-C ligand 2 in stroma is associated with recurrent basal-like breast cancers

Despite advances in treatment, up to 30% of breast cancer patients experience disease recurrence accompanied by more aggressive disease and poorer prognosis. Treatment of breast cancer is complicated by the presence of multiple breast cancer subtypes, including: luminal, Her2 overexpressing, and aggressive basal-like breast cancers. Identifying new biomarkers specific to breast cancer subtypes could enhance the prediction of patient prognosis and contribute to improved treatment strategies. The microenvironment influences breast cancer progression through expression of growth factors, angiogenic factors and other soluble proteins. In particular, chemokine C-C ligand 2 (CCL2) regulates macrophage recruitment to primary tumors and signals to cancer cells to promote breast tumor progression. Here we employed a software-based approach to evaluate the prognostic significance of CCL2 protein expression in breast cancer subtypes in relation to its expression in the epithelium or stroma or in relation to fibroblast-specific protein 1 (Fsp1), a mesenchymal marker. Immunohistochemistry analysis of tissue microarrays revealed that CCL2 significantly correlated with Fsp1 expression in the stroma and tumor epithelium of invasive ductal carcinoma. In the overall cohort of invasive ductal carcinomas (n=427), CCL2 and Fsp1 expression in whole tissues, stroma and epithelium were inversely associated with cancer stage and tumor size. When factoring in molecular subtype, stromal CCL2 was observed to be most highly expressed in basal-like breast cancers. By Cox regression modeling, stromal CCL2, but not epithelial CCL2, expression was significantly associated with decreased recurrence-free survival. Furthermore, stromal CCL2 (HR=7.51 P=0.007) was associated with a greater hazard than cancer stage (HR=2.45, P=0.048) in multivariate analysis. These studies indicate that stromal CCL2 is associated with decreased recurrence-free survival in patients with basal-like breast cancer, with important implications on the use of stromal markers for predicting patient prognosis.

Obesity and Breast Cancer: Do Age, Race and Subtype Matter?

Obesity rates within the United States are on the rise. Obesity is a known risk factor for various diseases, including cancer. Numerous studies have linked obesity to the incidence and treatment outcomes of breast cancer. However, the risk of obesity may vary between breast cancer subtypes and different racial or age groups. In this article, we review the literature regarding the impact of obesity on incidence and response for different subtypes of breast cancer within different population groups.

Impact of Preexisting Mental Illnesses on Receipt of Guideline-Consistent Breast Cancer Treatment and Health Care Utilization

This study determined the impact of preexisting mental illnesses on guideline-consistent breast cancer treatment and breast cancer-related health care utilization. This was a retrospective, longitudinal, cohort study conducted using data from the 2006-2008 Medicaid Analytic Extract files. The target population for the study consisted of female Medicaid enrollees who were aged 18-64 years and were newly diagnosed with breast cancer in 2007. Guideline-consistent breast cancer treatment was defined according to established guidelines. Breast cancer-related health care use was reported in the form of inpatient, outpatient, and emergency room visits. Statistical analyses consisted of multivariable hierarchical regression models. A total of 2142 newly diagnosed cases of breast cancer were identified. Approximately 38% of these had a preexisting mental illness. Individuals with any preexisting mental illness were less likely to receive guideline-consistent breast cancer treatment compared to those without any preexisting mental illness (adjusted odds ratio: 0.793, 95% confidence interval [CI]: 0.646-0.973). A negative association was observed between preexisting mental illness and breast cancer-related outpatient (adjusted incident rate ratio (AIRR): 0.917, 95% CI: 0.892-0.942) and emergency room utilization (AIRR: 0.842, 95% CI: 0.709-0.999). The association between preexisting mental illnesses and breast cancer-related inpatient utilization was statistically insignificant (AIRR: 0.993, 95% CI: 0.851-1.159). The findings of this study indicate that breast cancer patients with preexisting mental illnesses experience disparities in terms of receipt of guideline-consistent breast cancer treatment and health care utilization. The results of this study highlight the need for more focused care for patients with preexisting mental illness.

The impact of overweight and obesity on breast cancer: data from Switzerland, so far a country little affected by the current global obesity epidemic

This review presents results from the project "The Impact of Overweight/Obesity on Breast Cancer: data from Switzerland". Swiss data is interesting because the general female population is distinctive in two areas when compared to that of most other industrialized countries: Switzerland has comparatively low rates of overweight (22-23%) and obesity (7-8%) and has rather stable rates of overweight and obesity. The entire project comprised three major issues: (I) etiology of breast cancer (BC). There is a consistently shown association between obesity and postmenopausal BC risk in countries with high obesity prevalence rates in the literature. In our Swiss study group, however, we did not find higher rates of overweight and obesity in postmenopausal BC cases than in the general population. A possible explanation for this observation may be a curvilinear dose-response relationship between BMI and postmenopausal BC risk, so that an increased risk may only be observed in populations with a high prevalence of obese/very obese women; (II) tumor characteristics. BMI was significantly associated with tumor size; this applied not only to the cases where the tumor was found by self-detection, but also to lesions detected by radiological breast examinations. In addition, a higher BMI was positively correlated with advanced TNM stage, unfavorable grading and a higher St. Gallen risk score. No associations were observed between BMI and histological subtype, estrogen receptor status, HER2 status and triple negative BC; (III) patient compliance and persistence towards adjuvant BC therapy. Many studies found that the prognosis of overweight/obese BC patients was significantly lower than that of normal weight patients. However, failure of compliance and persistence towards therapy on the part of the patient is not a contributing factor for this observed unfavorable prognosis. In most therapy modes, patients with increasing BMI demonstrated greater motivation and perseverance towards the recommended treatment.

Impact of body mass index on prognostically relevant breast cancer tumor characteristics

BACKGROUND

This study analyzes the association of body mass index (BMI) and prognostically relevant breast cancer (BC) characteristics in a country that has been rather spared of the global obesity epidemic.

PATIENTS AND METHODS

Based on 20-year data (1999-2009, n = 1,414) of the prospective relational BC database of the University Hospital Basel, Switzerland, the associations between BMI, tumor size and stage, histological subtype, grading, hormonal receptor status, HER2 status and 'triple-negative' status were evaluated. Multivariate analysis considered BMI and patient's age.

RESULTS

The association between increasing BMI and the above-mentioned variables were as follows (results described in each case: Beta-coefficient or odds ratio, 95% confidence interval, p value): tumor size, (1) entire cohort: 0.03 (0.01-0.05), p < 0.001, (2) tumor found by self-palpation: 0.05 (0.03-0.07), p < 0.001, (3) tumor found by radiological examination: 0.03 (0-0.07), p = 0.044; advanced TNM stage: 1.16 (1.02-1.31), p = 0.022; histological subtype: 1.04 (0.89-1.22), p = 0.602; unfavorable grading: 1.11 (1.00-1.25), p = 0.057; positive estrogen receptor status: 0.95 (0.83-1.09), p = 0.459; positive HER2 status: 0.92 (0.74-1.15), p = 0.467; presence of a 'triple-negative' carcinoma: 1.19 (0.93-1.52), p = 0.165. Consideration of only postmenopausal BC patients (n = 1,063) did attenuate the results, but did not change the direction of the associations with BMI.

CONCLUSION

BMI was positively associated with TNM stage, grading and tumor size for tumors that were found by self-detection, as well as for those lesions detected by radiological breast examinations.

The effects of soy consumption before diagnosis on breast cancer survival: the Multiethnic Cohort Study

This study tested the hypothesis that prediagnostic soy intake was inversely associated with all-cause and breast cancer-specific mortality. The analyses included 3842 women in the Multiethnic Cohort (MEC) study of African Americans, Native Hawaiians, Japanese Americans, Latinos, and Caucasians, who completed a quantitative food frequency questionnaire, aged ≥50 yr at cohort entry, and diagnosed with primary invasive breast cancer following cohort entry (1993-2007). Hazard ratios (HR) and 95% confidence intervals (CI) were estimated from Cox proportional hazards regression with adjustment for known clinical and lifestyle factors. During a mean follow-up after diagnosis of invasive breast cancer of 6.2 ± 3.8 yr, there were 804 deaths including 376 breast cancer-specific deaths. The HR (95%CI) for all-cause and breast cancer-specific morality comparing the highest versus lowest tertiles were 1.03 (0.81-1.33) and 1.03 (0.71-1.50) for soy products and 0.99 (0.82-1.20) and 0.95 (0.71-1.28) for total isoflavones, respectively (Ptrend > 0.60 for all). There was limited evidence of differences by hormone receptor status, tumor stage, or ethnic group. Prediagnostic soy intake was unrelated to mortality in postmenopausal women. Our findings are consistent with the literature that soy consumption does not adversely affect breast cancer survival in women.

Obesity and risk of breast cancer mortality in Hispanic and Non-Hispanic white women: the New Mexico Women's Health Study

Obesity is reported to be associated with poorer survival in women with breast cancer, regardless of menopausal status. Our purpose was to determine if the associations of obesity with breast cancer-specific, all-cause, and non-breast cancer mortality differ between Hispanic and non-Hispanic white (NHW) women with breast cancer. Data on lifestyle and medical history were collected for incident primary breast cancer cases (298 NHW, 279 Hispanic) in the New Mexico Women's Health Study. Mortality was ascertained through the National Death Index and New Mexico Tumor Registry over 13 years of follow-up. Adjusted Cox regression models indicated a trend towards increased risk for breast cancer-specific mortality in obese NHW women (hazard ratio [HR] 2.07; 95% confidence interval [CI] 0.98-4.35) but not in Hispanic women (HR 1.32; 95% CI 0.64-2.74). Obese NHW women had a statistically significant increased risk for all-cause mortality (HR 2.12; 95% CI 1.15-3.90) while Hispanic women did not (HR 1.23; 95% CI 0.71-2.12). Results were similar for non-breast cancer mortality: NHW (HR 2.65; 95% CI 0.90-7.81); Hispanic (HR 2.18; 95% CI 0.77-6.10). Our results suggest that obesity is associated with increased risk for breast cancer-specific mortality in NHW women; however, this association is attenuated in Hispanic women.

Ethnic differences in breast cancer survival: status and determinants

Ethnic differences in breast cancer survival have been a long-standing concern. The objective of this article is to present relevant studies for all major US racial/ethnic groups including African-Americans, Latinos, Native Americans, Japanese-Americans and Native Hawaiians, and to discuss underlying causes of disparity. In comparison to Caucasian women, African-American women continue to experience the poorest breast cancer-specific survival of all ethnic groups in the USA. The prognosis for Latinos, Native Hawaiians and Native Americans is intermediate, better than for African-Americans but not as good as for Caucasians, whereas Japanese-American women tend to have better outcomes. The following possible contributors to the observed differences are discussed in detail: unfavorable distribution of stage at diagnosis due to low screening rates, limited access to care and treatment, tumor type, comorbidities, socioeconomic status, obesity and physical activity.

Impact of body mass index on compliance and persistence to adjuvant breast cancer therapy

Several authors found that the prognosis of overweight and obese breast cancer (BC) patients was lower than that of normal weight patients. We present the first study which evaluates the impact of body mass index (BMI) on compliance (i.e. to start a recommended therapy) and persistence to adjuvant BC therapy. An unselected cohort of 766 patients (≤75 years) diagnosed from 1997 to 2009 was analyzed in relevance to the four adjuvant therapy modalities: (A) radiation, (B) chemotherapy, (C) therapy with trastuzumab, and (D) endocrine therapy. With respect to compliance, multivariate analyses calculated Odds ratios (ORs) >1 for increased BMI in all four therapy modalities, i.e. increased BMI had a positive influence on compliance. The results were significant for radiotherapy (OR,2.37;95%CI,1.45-3.88;p < 0.001) and endocrine therapy (OR,1.92;95%CI,1.21-3.04;p = 0.002) and showed a trend in chemotherapy (OR,1.42;95%CI,0.97-2.08;p = 0.063). Analyzing persistence, increasing BMI had ORs <1 for chemotherapy and therapy with trastuzumab, both not reaching statistical significance. For endocrine therapy, increasing BMI was a significant predictor for persistence (OR,1.35;95%CI,1.08-1.80;p = 0.042). Failure of compliance and persistence to adjuvant therapy does not pose a contributing factor for the observed unfavorable prognosis in overweight/obese BC patients. In most therapy modes, patients with increasing BMI demonstrated a higher motivation and perseverance to the recommended treatment.

Obesity and breast cancer survival in ethnically diverse postmenopausal women: the Multiethnic Cohort Study

Breast cancer survival has been found to be lower in obese women, but few studies have evaluated ethnic variations in this association. This study examined all-cause and breast cancer-specific survival by body mass index (BMI) in the Multiethnic Cohort (MEC) study for African American, Native Hawaiian, Japanese American, Latino, and Caucasian women. Female MEC participants free of breast cancer, aged ≥50 years at cohort entry, and diagnosed with primary invasive breast cancer during follow-up were included in the analyses (n = 3,842). Cox proportional hazards regression was used to estimate the effect of pre-diagnostic adult BMI (<22.5, 22.5-24.9, 25.0-29.9, ≥30 kg/m(2)) on the risk of mortality. Mean age at diagnosis was 68.8 years (range 50-89 years). During a mean follow-up of 6.2 ± 3.8 years after diagnosis, there were 804 deaths that included 376 breast cancer-specific deaths. After adjustment for breast cancer characteristics, including hormone receptor status, stage at diagnosis, and treatment, obese women had a higher risk of all-cause [hazard ratio (HR) = 1.54; 95% confidence interval (CI): 1.23, 1.91] and breast cancer-specific (HR = 1.45; 95% CI: 1.05, 2.00) mortality compared to women with high-normal BMI; however, being overweight did not affect survival. There was no evidence of ethnic differences in the BMI effect on all-cause (P (interaction) = 0.87) or breast cancer-specific (P (interaction) = 0.63) mortality. Our findings are consistent with the literature that maintaining moderate weight throughout adult life may be beneficial for breast cancer survival in women and this appears to hold for all ethnic groups.