How much do tumor stage and treatment explain socioeconomic inequalities in breast cancer survival? Applying causal mediation analysis to population-based data

[Impact of precariousness on breast cancer care in the Île-de-France region: Results of the DESSEIN study]

INTRODUCTION

Precariousness has been associated with an increase in breast cancer mortality, but the links between precariousness, stage at diagnosis and care pathways are little explored. The objective of the DESSEIN study was to assess the impact of precariousness on disease and care pathways.

METHODS

Prospective observational study in Île-de-France comparing precarious and non-precarious patients consulting for breast cancer and followed for 1 year.

RESULTS

In total, 875 patients were included between 2016 and 2019 in 19 institutions: 543 non-precarious patients and 332 precarious patients. Precarious patients had a more advanced stage at diagnosis (55% T1 vs. 63%, 30% N+ vs 19%, P=0.0006), had a higher risk of not receiving initially planned treatment (4 vs. 1%, P=0.004), and participated less in clinical trials (5 vs. 9%, P=0.03). Non-use of supportive oncology care was 2 times more frequent among patients in precarious situations (P<0.001). During treatment, 33% of deprived patients reported a loss of income, compared with 24% of non-deprived patients (P<0.001). At 12 months from diagnosis, lay-offs were 2 times more frequent in precarious patients (P=0.0001).

DISCUSSION

Precariousness affects all stages of the cancer history and care pathway. Particular attention needs to be paid to vulnerable populations, considering issues of accessibility and affordability of care, health literacy and possible implicit bias from the care providers.

Where are the inequalities in ovarian cancer care in a country with universal healthcare? A systematic review and narrative synthesis

INTRODUCTION

Patients diagnosed with ovarian cancer from more deprived areas may face barriers to accessing timely, quality healthcare. We evaluated the literature for any association between socioeconomic group, treatments received and hospital delay among patients diagnosed with ovarian cancer in the United Kingdom, a country with universal healthcare.

METHODS

We searched MEDLINE, EMBASE, CINAHL, CENTRAL, SCIE, AMED, PsycINFO and HMIC from inception to January 2023. Forward and backward citation searches were conducted. Two reviewers independently reviewed titles, abstracts, and full-text articles. UK-based studies were included if they reported socioeconomic measures and an association with either treatments received or hospital delay. The inclusion of studies from one country ensured greater comparability. Risk of bias was assessed using the QUIPS tool, and a narrative synthesis was conducted. The review is reported to PRISMA 2020 and registered with PROSPERO [CRD42022332071].

RESULTS

Out of 2876 references screened, ten were included. Eight studies evaluated treatments received, and two evaluated hospital delays. We consistently observed socioeconomic inequalities in the likelihood of surgery (range of odds ratios 0.24-0.99) and chemotherapy (range of odds ratios 0.70-0.99) among patients from the most, compared with the least, deprived areas. There were no associations between socioeconomic groups and hospital delay.

POLICY SUMMARY

Ovarian cancer treatments differed between socioeconomic groups despite the availability of universal healthcare. Further research is needed to understand why, though suggested reasons include patient choice, health literacy, and financial and employment factors. Qualitative research would provide a rich understanding of the complex factors that drive these inequalities.

The Impact of Health Inequities on Population-Based Breast Cancer Survival in a Colombian Population, 2008-2015

OBJECTIVE

To obtain breast cancer survival estimates in Manizales, Colombia, considering socioeconomic level, health insurance regime and residential area, while adjusting for age, histology and stage at diagnosis.

METHODS

Analytical cohort study based on breast cancer incident cases recorded by the Population-based Manizales Cancer Registry between 2008-2015. Patients were followed-up for 60 months. Cause-specific survival was calculated using the Kaplan-Meier method for variables of interest, with the Wilcoxon-Breslow-Gehan test for differences. Cox multivariate regression models were fitted.

RESULTS

856 breast cancer cases were included. The 5-year cause-specific survival for the entire cohort was 78.2%. It was higher in women with special/exception health insurance, high socioeconomic level, <50 years old, ductal carcinoma, and stages I and II. Residential area did not impact survival. In Cox models, the subsidized health insurance regime (HR: 4.87 vs contributory) and low socioeconomic level (HR: 2.45 vs high) were predictors of the hazard of death in women with breast cancer, adjusted for age, histology, stage and interactions age-stage and insurance-stage. A positive interaction (synergistic effect modification) between health insurance regime and stage regarding to survival was observed.

CONCLUSION

Socioeconomic factors significantly contribute to the inequities in breast cancer survival, independent of the stage at diagnosis. This suggests the need for comprehensive interventions to remove barriers to accessing the health system. This research provides evidence of survival gaps mediated by certain social determinants of health and generates data on the overall performance of the Colombian health system.

Patterns of Evidence-Based Care for the Diagnosis, Staging, and First-line Treatment of Breast Cancer by Race-Ethnicity: A SEER-Medicare Study

BACKGROUND

Racial and ethnic disparities in guideline-recommended breast cancer treatment are well documented, however studies including diagnostic and staging procedures necessary to determine treatment indications are lacking. The purpose of this study was to characterize patterns in delivery of evidence-based services for the diagnosis, clinical workup, and first-line treatment of breast cancer by race-ethnicity.

METHODS

SEER-Medicare data were used to identify women diagnosed with invasive breast cancer between 2000 and 2017 at age 66 or older (n = 2,15,605). Evidence-based services included diagnostic procedures (diagnostic mammography and breast biopsy), clinical workup (stage and grade determination, lymph node biopsy, and HR and HER2 status determination), and treatment initiation (surgery, radiation, chemotherapy, hormone therapy, and HER2-targeted therapy). Poisson regression was used to estimate rate ratios (RR) and 95% confidence intervals (CI) for each service.

RESULTS

Black and American Indian/Alaska Native (AIAN) women had significantly lower rates of evidence-based care across the continuum from diagnostics through first-line treatment compared to non-Hispanic White (NHW) women. AIAN women had the lowest rates of HER2-targeted therapy and hormone therapy initiation. While Black women also had lower initiation of HER2-targeted therapy than NHW, differences in hormone therapy were not observed.

CONCLUSIONS

Our findings suggest patterns along the continuum of care from diagnostic procedures to treatment initiation may differ across race-ethnicity groups.

IMPACT

Efforts to improve delivery of guideline-concordant treatment and mitigate racial-ethnic disparities in healthcare and survival should include procedures performed as part of the diagnosis, clinical workup, and staging processes.

Socioeconomic Inequalities in Novel NSCLC Treatments During the Era of Tumor Biomarker-Guided Therapy: A Population-Based Cohort Study in a Publicly Funded Health Care System

INTRODUCTION

Socioeconomic inequalities in the utilization of conventional NSCLC treatments are well documented. Nevertheless, it is not known whether these inequalities are also observed with novel anticancer therapies. This study evaluated associations between deprivation and utilization of novel anticancer therapies targeting tumor biology, the immune system, or both, within the English national publicly funded health care system.

METHODS

A retrospective analysis of 90,785 patients diagnosed with having a histologically confirmed stage IV NSCLC from January 1, 2012, to December 31, 2017, sourced from the English national population-based cancer registry and linked Systemic Anti-Cancer Therapy database, was undertaken. Multivariable logistic regression evaluated the likelihood of novel anticancer therapy utilization by deprivation category of area of residence at diagnosis (measured by quintiles of the income domain of the index of multiple deprivation).

RESULTS

Multivariable analyses revealed marked treatment inequalities by deprivation. Patients residing in the most deprived areas were more than half as likely to use any novel therapy (multivariable OR [mvOR] = 0.45, 95% confidence interval [CI]: 0.41-0.49) compared with patients residing in the most affluent areas. Deprivation associations with treatment utilization were slightly stronger with targeted treatments ([most versus least deprived] mvOR = 0.39, 95% CI: 0.35-0.43) than immune checkpoint inhibitors (mvOR = 0.58, 95% CI: 0.51-0.66).

CONCLUSIONS

There are marked socioeconomic inequalities in NSCLC novel treatment utilization, even in the English National Health Service where treatment is free at the point of delivery. These findings have important implications for equitable delivery of drugs, which have transformed outcomes in metastatic lung cancer. Further work exploring the underlying causes is now needed.

The contribution of prognostic factors to socio-demographic inequalities in breast cancer survival in Victoria, Australia

BACKGROUND

Breast cancer survival in Australia varies according to socio-economic status (SES) and between rural and urban places of residence. Part of this disparity may be due to differences in prognostic factors at the time of diagnosis.

METHODS

Women with invasive breast cancer diagnosed from 2008 until 2012 (n = 14,165) were identified from the Victorian Cancer Registry and followed up for 5 years, with death from breast cancer or other causes recorded. A prognostic score, based on stage at diagnosis, cancer grade, whether the cancer was detected via screening, reported comorbidities and age at diagnosis, was constructed for use in a mediation analysis.

RESULTS

Five-year breast cancer mortality for women with breast cancer who were in the lowest quintile of SES (10.3%) was almost double that of those in the highest quintile (5.7%). There was a small survival advantage (1.7% on average, within each socio-economic quintile) of living in inner-regional areas compared with major cities. About half of the socio-economic disparity was mediated by prognostic factors, particularly stage at diagnosis and the presence of comorbidities. The inner-regional survival advantage was not due to differences in prognostic factors.

CONCLUSIONS

Part of the socio-economic disparity in breast cancer survival could be addressed by earlier detection in, and improved general health for, more disadvantaged women. Further research is required to identify additional causes of socio-economic disparities as well as the observed inner-regional survival advantage.

Dynamic changes in quality of life, psychological status, and body image in women who underwent a mastectomy as compared with breast reconstruction: an 8-year follow up

BACKGROUND

Surgical decisions and methods of surgery highly influence long term QoL for breast cancer (BC) survivors. This study is aimed towards an exploration of the dynamic changes in quality of life (QoL), anxiety/depression status, and body image (BI) among women with BC who received a mastectomy compared with those receiving breast reconstruction (BR) within an 8-year follow-up period.

METHODS

Women with major BC surgeries were invited to complete the World Health Organization Quality of Life-Brief (WHOQOL-BREF), the European quality of life five dimensions questionnaire (EQ-5D), and a body image scale within 8 years of surgery. Kernel smoothing methods were applied to describe dynamic changes in QoL, anxiety/depression, and BI at different time points. Linear mixed effects models were constructed to identify the interaction between time, different types of surgery, and the determinants of QoL in these patients.

RESULTS

After 1:10 propensity score matching, a total of 741 women who had undergone a BR and mastectomy were included. The BR group exhibited a high WHOQOL QoL score one to five years after surgery with some fluctuations. The mastectomy group had comparatively stable QoL scores on WHOQOL items and were less depressed/anxious. The BR group generally showed fluctuating, higher BI scores two years after surgery, but they exhibited more anxiety/depression during follow up for 8 years. Medical comorbidities, the status of anxiety/depression, and BI were the major factors influencing all domains and items of the WHOQOL BREF among women with BC.

CONCLUSION

The mastectomy group showed a decreased trend toward depression in patients with BC. The BR group showed a significant improvement in QoL in the first 5 years with massive fluctuations. These findings should be considered and discussed in patient participatory decision-making and promotion of QoL for breast cancer survivors.

Is survival rate lower after breast cancer in deprived women according to disease stage?

BACKGROUND

Socioeconomic deprivation has been associated with lower breast cancer (BC) survival, but the influence of stage at diagnosis on this association merits further study. Our aim was to investigate this association using the Loire-Atlantique/Vendee Cancer Registry (France).

METHODS

Twelve-thousand seven-hundred thirty-eight women living in the area covered by the registry and diagnosed with invasive breast carcinoma between 2008 and 2015 were included in the study. They were censored at maximal 6 years. Deprivation was measured by the French European Deprivation Index. Excess hazard and net survival were estimated for deprivation level, stage and age at diagnosis using a flexible excess mortality hazard model.

RESULTS

After adjustment by stage, women living in the most deprived areas had a borderline non-significant higher excess mortality hazard (+25% (95% CI: -3%; +62%)) compared to those living in the least deprived areas. Stage-adjusted 5-year net survival differed significantly between these two subgroups (respectively, 88.2% (95% CI:85.2%-90.5%) and 92.5% (95% CI:90.6%-93.9%)).

CONCLUSION

BC survival remained lower in deprived areas in France, despite universal access to cancer care. Intensification of prevention measures could help to reduce advanced BC, responsible for the majority of deaths from BC. A better understanding of remaining social disparities is crucial to implement specific interventions.

Mediating Effects of Diagnostic Route on the Comorbidity Gap in Survival of Patients with Diffuse Large B-Cell or Follicular Lymphoma in England

Background: Socioeconomic inequalities in survival from non-Hodgkin lymphoma persist. Comorbidities are more prevalent amongst those in more deprived areas and are associated with diagnostic delay (emergency diagnostic route), which is also associated with poorer survival probability. We aimed to describe the effect of comorbidity on the probability of death mediated by diagnostic route (emergency vs. elective route) amongst patients with diffuse large B-cell (DLBCL) or follicular lymphoma (FL). Methods: We linked the English population-based cancer registry and hospital admission records (2005-2013) of patients aged 45-99 years. We decomposed the effect of comorbidity on survival into an indirect effect acting through diagnostic route and a direct effect not mediated by diagnostic route. Furthermore, we estimated the proportion of the comorbidity effect on survival mediated by diagnostic route. Results: For both DLBCL (n = 27,379) and FL (n = 14,043), those with any comorbidity, or living in more deprived areas, were more likely to experience diagnostic delay and poorer survival. The indirect effect of comorbidity on mortality through diagnostic route was highest at 12 months since diagnosis (DLBCL: Odds Ratio 1.10 [95% CI 1.07-1.13], FL: OR 1.09 [95% CI 1.04-1.14]). Within the first 12 months since diagnosis, emergency diagnostic route accounted for 24% (95% CI 17.5-29.5) and 16% (95% CI 6.0-25.6) of the comorbidity effect on mortality, for DLBCL and FL, respectively. Conclusion: Efforts to reduce diagnostic delay (emergency diagnosis) amongst patients with comorbidity would reduce inequalities in DLBCL and FL survival by 24% and 16%, respectively. Further public health programs and interventions are needed to reduce diagnostic delay amongst lymphoma patients with comorbidities.

Socioeconomic inequalities in breast cancer survival in Reunion Island: The contribution of stage at diagnosis as a mediator

INTRODUCTION

Although breast cancer survival has improved in France, it appears that women living in deprived areas are more likely to die from breast cancer. However, no study has yet examined socioeconomic inequalities in breast cancer survival in La Réunion. Our objective was to examine whether socioeconomic inequalities in breast cancer survival exist in Reunion Island and whether stage at diagnosis could partly explain these differences.

METHODS

A population-based cohort study of all women on Reunion Island with primary breast cancer diagnosed between 2008 and 2016 was conducted. Each woman was assigned a deprivation index based on her area of residence at diagnosis. Net survival by deprivation group and stage at diagnosis was estimated by the non parametric Pohar Perme method. The role of stage (indirect effect) was assessed using a mediation analysis extended to the relative survival framework.

RESULTS

At five years, net survival was significantly lower in women living in the most deprived areas than in women living in the least deprived areas (81 % (95 % CI 77-86) and 91 % (95 % CI 89-94), respectively, p < 0.0001), and mediation analysis showed that the contribution of stage at diagnosis to these survival differences was 43 %.

DISCUSSION

Our result shows that although measures to promote earlier diagnosis are important, they would only reduce socioeconomic inequalities in breast cancer survival by 43 %. To further investigate these inequalities, future research should explore the role of unmeasured mediators, such as comorbidities and treatment received, as well as the impact of specific interventions that might address the differences in mediator distribution.

Socio-economic inequalities in cancer survival: how do they translate into Number of Life-Years Lost?

BACKGROUND

We aimed to investigate the impact of socio-economic inequalities in cancer survival in England on the Number of Life-Years Lost (NLYL) due to cancer.

METHODS

We analysed 1.2 million patients diagnosed with one of the 23 most common cancers (92.3% of all incident cancers in England) between 2010 and 2014. Socio-economic deprivation of patients was based on the income domain of the English Index of Deprivation. We estimated the NLYL due to cancer within 3 years since diagnosis for each cancer and stratified by sex, age and deprivation, using a non-parametric approach. The relative survival framework enables us to disentangle death from cancer and death from other causes without the information on the cause of death.

RESULTS

The largest socio-economic inequalities were seen mostly in adults <45 years with poor-prognosis cancers. In this age group, the most deprived patients with lung, pancreatic and oesophageal cancer lost up to 6 additional months within 3 years since diagnosis than the least deprived. For most moderate/good prognosis cancers, the socio-economic inequalities widened with age.

CONCLUSIONS

More deprived patients and particularly the young with more lethal cancers, lose systematically more life-years than the less deprived. To reduce these inequalities, cancer policies should systematically encompass the inequities component.

Excess Mortality by Multimorbidity, Socioeconomic, and Healthcare Factors, amongst Patients Diagnosed with Diffuse Large B-Cell or Follicular Lymphoma in England

(1) Background: Socioeconomic inequalities of survival in patients with lymphoma persist, which may be explained by patients' comorbidities. We aimed to assess the association between comorbidities and the survival of patients diagnosed with diffuse large B-cell (DLBCL) or follicular lymphoma (FL) in England accounting for other socio-demographic characteristics. (2) Methods: Population-based cancer registry data were linked to Hospital Episode Statistics. We used a flexible multilevel excess hazard model to estimate excess mortality and net survival by patient's comorbidity status, adjusted for sociodemographic, economic, and healthcare factors, and accounting for the patient's area of residence. We used the latent normal joint modelling multiple imputation approach for missing data. (3) Results: Overall, 15,516 and 29,898 patients were diagnosed with FL and DLBCL in England between 2005 and 2013, respectively. Amongst DLBCL and FL patients, respectively, those in the most deprived areas showed 1.22 (95% confidence interval (CI): 1.18-1.27) and 1.45 (95% CI: 1.30-1.62) times higher excess mortality hazard compared to those in the least deprived areas, adjusted for comorbidity status, age at diagnosis, sex, ethnicity, and route to diagnosis. (4) Conclusions: Deprivation is consistently associated with poorer survival among patients diagnosed with DLBCL or FL, after adjusting for co/multimorbidities. Comorbidities and multimorbidities need to be considered when planning public health interventions targeting haematological malignancies in England.

Are socio-economic inequalities in breast cancer survival explained by peri-diagnostic factors?

BACKGROUND

Patients living in more deprived localities have lower cancer survival in England, but the role of individual health status at diagnosis and the utilisation of primary health care in explaining these differentials has not been widely considered. We set out to evaluate whether pre-existing individual health status at diagnosis and primary care consultation history (peri-diagnostic factors) could explain socio-economic differentials in survival amongst women diagnosed with breast cancer.

METHODS

We conducted a retrospective cohort study of women aged 15-99 years diagnosed in England using linked routine data. Ecologically-derived measures of income deprivation were combined with individually-linked data from the English National Cancer Registry, Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. Smoking status, alcohol consumption, BMI, comorbidity, and consultation histories were derived for all patients. Time to breast surgery was derived for women diagnosed after 2005. We estimated net survival and modelled the excess hazard ratio of breast cancer death using flexible parametric models. We accounted for missing data using multiple imputation.

RESULTS

Net survival was lower amongst more deprived women, with a single unit increase in deprivation quintile inferring a 4.4% (95% CI 1.4-8.8) increase in excess mortality. Peri-diagnostic co-variables varied by deprivation but did not explain the differentials in multivariable analyses.

CONCLUSIONS

These data show that socio-economic inequalities in survival cannot be explained by consultation history or by pre-existing individual health status, as measured in primary care. Differentials in the effectiveness of treatment, beyond those measuring the inclusion of breast surgery and the timing of surgery, should be considered as part of the wider effort to reduce inequalities in premature mortality.

Factors Explaining Socio-Economic Inequalities in Cancer Survival: A Systematic Review

BACKGROUND

There is strong and well-documented evidence that socio-economic inequality in cancer survival exists within and between countries, but the underlying causes of these differences are not well understood.

METHODS

We systematically searched the Ovid Medline, EMBASE, and CINAHL databases up to 31 May 2020. Observational studies exploring pathways by which socio-economic position (SEP) might causally influence cancer survival were included.

RESULTS

We found 74 eligible articles published between 2005 and 2020. Cancer stage, other tumor characteristics, health-related lifestyle behaviors, co-morbidities and treatment were reported as key contributing factors, although the potential mediating effect of these factors varied across cancer sites. For common cancers such as breast and prostate cancer, stage of disease was generally cited as the primary explanatory factor, while co-morbid conditions and treatment were also reported to contribute to lower survival for more disadvantaged cases. In contrast, for colorectal cancer, most studies found that stage did not explain the observed differences in survival by SEP. For lung cancer, inequalities in survival appear to be partly explained by receipt of treatment and co-morbidities.

CONCLUSIONS

Most studies compared regression models with and without adjusting for potential mediators; this method has several limitations in the presence of multiple mediators that could result in biased estimates of mediating effects and invalid conclusions. It is therefore essential that future studies apply modern methods of causal mediation analysis to accurately estimate the contribution of potential explanatory factors for these inequalities, which may translate into effective interventions to improve survival for disadvantaged cancer patients.

Exploring socioeconomic differences in surgery and in time to elective surgery for colon cancer in England: Population-based study

BACKGROUND

A persistent socioeconomic gap in colon cancer survival is observed in England. Provision of cancer care may also vary by socioeconomic status (SES). We investigated population-based data to explore differential surgical care by SES.

METHODS

We analysed a retrospective cohort of patients diagnosed with colon cancer in England (2010-2013). We examined patterns of presentation and surgery by SES, and whether socioeconomic differences exist in the length of time from diagnosis to elective major resection using linear regression.

RESULTS

Among a total of 68 169 patients with colon cancer, 21.0 % (3138/14 917) in the most affluent group had emergency presentation (EP) whereas 27.9 % (2901/10 386) in the most deprived. Among 45 332 (66.5 %) patients who underwent resection, the proportion of patients receiving urgent surgery (surgery before or ≤ 7 days of diagnosis) was higher in the most deprived group (39.9 %, 2685/6733) than the most affluent (35.4 %, 3595/10 146). Days from diagnosis to elective surgery (surgery > 7 days after diagnosis) ranged from 33.9 (95 % CI 33.1-34.8) in stage II to 38.2 (95 % CI 36.8-39.7) in stage I, but no socioeconomic differences in time were seen in all stages.

CONCLUSIONS

Time to elective surgery for colon cancer did not differ by SES, whereas a higher proportion among deprived patients tended to be diagnosed through EP and to receive urgent surgery. These results suggest that the waiting time target may not be an appropriate measure to assess access to cancer care. Reducing both EP and urgent surgery should be a key policy target.

Socioeconomic disparities in head and neck cancer survival in Germany: a causal mediation analysis using population-based cancer registry data

PURPOSE

Despite recent improvements in cancer treatment in Germany, a marked difference in cancer survival based on socioeconomic factors persists. We aim to quantify the effect of socioeconomic inequality on head and neck cancer (HNC) survival.

METHODS

Information on 20,821 HNC patients diagnosed in 2009-2013 was routinely collected by German population-based cancer registries. Socioeconomic inequality was defined by the German Index of Socioeconomic Deprivation. The Cox proportional regression and relative survival analysis measured the survival disparity according to level of socioeconomic deprivation with respective confidence intervals (CI). A causal mediation analysis was conducted to quantify the effect of socioeconomic deprivation mediated through medical care, stage at diagnosis, and treatment on HNC survival.

RESULTS

The most socioeconomically deprived patients were found to have the highest hazard of dying when compared to the most affluent (Hazard Ratio: 1.25, 95% CI 1.17-1.34). The most deprived patients also had the worst 5-year age-adjusted relative survival (50.8%, 95% CI 48.5-53.0). Our mediation analysis showed that most of the effect of deprivation on survival was mediated through differential stage at diagnosis during the first 6 months after HNC diagnosis. As follow-up time increased, medical care, stage at diagnosis, and treatment played no role in mediating the effect of deprivation on survival.

CONCLUSION

This study confirms the survival disparity between affluent and deprived HNC patients in Germany. Considering data limitations, our results suggest that, within six months after HNC diagnosis, the elimination of differences in stage at diagnosis could reduce survival inequalities.

Stage-specific survival has improved for young breast cancer patients since 2000: but not equally

Purpose

The stage-specific survival of young breast cancer patients has improved, likely due to diagnostic and treatment advances. We addressed whether survival improvements have reached all socioeconomic groups in a country with universal health care and national treatment guidelines.

Methods

Using Norwegian registry data, we assessed stage-specific breast cancer survival by education and income level of 7501 patients (2317 localized, 4457 regional, 233 distant and 494 unknown stage) aged 30–48 years at diagnosis during 2000–2015. Using flexible parametric models and national life tables, we compared excess mortality up to 12 years from diagnosis and 5-year relative survival trends, by education and income as measures of socioeconomic status (SES).

Results

Throughout 2000–2015, regional and distant stage 5-year relative survival improved steadily for patients with high education and high income (high SES), but not for patients with low education and low income (low SES). Regional stage 5-year relative survival improved from 85 to 94% for high SES patients (9% change; 95% confidence interval: 6, 13%), but remained at 84% for low SES patients (0% change; − 12, 12%). Distant stage 5-year relative survival improved from 22 to 58% for high SES patients (36% change; 24, 49%), but remained at 11% for low SES patients (0% change; − 19, 19%).

Conclusions

Regional and distant stage breast cancer survival has improved markedly for high SES patients, but there has been little survival gain for low SES patients. Socioeconomic status matters for the stage-specific survival of young breast cancer patients, even with universal health care.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05698-z) contains supplementary material, which is available to authorized users.

Association between socioeconomic factors at diagnosis and survival in breast cancer: A population-based study

Background

The associations between socioeconomic statuses and survival outcomes of breast cancer remain unclear. No model has included both histological and socioeconomic factors to predict the survival of breast cancer. This study was designed to develop nomograms to predict breast cancer–specific survival (BCSS) and overall survival (OS) with consideration of socioeconomic factors for breast cancer patients.

Materials and methods

We included a total of 207 749 female patients, diagnosed with malignant breast cancer between 2007 and 2012 from the Surveillance, Epidemiology, and End Results database. BCSS and OS were evaluated with Gray's test and log‐rank tests, respectively. Marital statuses, insurance statuses, residence, median household income, poverty rate, unemployment rate, and education level were included as socioeconomic factors in univariate and multivariate Cox regression analyses. Clinicopathological factors and socioeconomic factors were integrated to construct nomograms. Calibration plots and concordance indexes (C‐indexes) were used to evaluate the accuracy and discrimination of the models.

Results

Four and three socioeconomic factors were involved in constructing the nomograms for 3‐, 5‐, and 7‐year BCSS and OS, respectively. The C‐indexes of the final nomograms were higher than those of the TNM staging system for predicting BCSS (0.835 vs 0.782; P < .001) and OS (0.773 vs 0.676; P < .001). The performance of the nomograms for predicting OS was significantly lower when excluding socioeconomic factors (P < .001).

Conclusion

These findings may highlight the importance of developing health‐related policies and the necessity of targeted social support‐based interventions for high‐risk patients.

Which indicators of early cancer diagnosis from population-based data sources are associated with short-term mortality and survival?

BACKGROUND

A key component of recent English cancer policy is the monitoring of trends in early diagnosis of cancer. Early diagnosis can be defined by the disease stage at diagnosis or by other indicators derived from electronic health records. We evaluate the association between different early diagnosis indicators and survival, and discuss the implementation of the indicators in surveillance of early diagnosis.

METHODS

We searched the PubMed database and grey literature to identify early diagnosis indicators and evaluate their association with survival. We analysed cancer registrations for 355,502 cancer patients diagnosed in England during the period 2009-2013, and quantified the association between each early diagnosis indicator and 30-day mortality and five-year net survival.

RESULTS

Each incremental difference in stage (I-IV) predicts lower 5-year survival, so prognostic information is lost in comparisons which use binary stage indicators. Patients without a recorded stage have high risk of death shortly following diagnosis and lower 5-year survival. Emergency presentation is independently associated with lower five-year survival. Shorter intervals between first symptoms and diagnosis are not consistently associated with improved survival, potentially due to confounding from tumour characteristics.

INTERPRETATION

Contrary to current practice, we recommend that all the stage information should be used in surveillance. Patients missing stage should also be included to minimise bias. Combined data on stage and emergency presentation could be used to create summary prognostic measures. More work is needed to create statistics based on the diagnostic interval that will be useful for surveillance.

Disparidade racial na sobrevivência em 10 anos para o câncer de mama: uma análise de mediação usando abordagem de respostas potenciais

Os objetivos foram investigar a associação entre raça/cor e a sobrevivência em 10 anos de mulheres com câncer de mama e o papel do estadiamento como mediador. Coorte hospitalar com 481 mulheres com câncer invasivo de mama, diagnosticadas entre 2003 e 2005. Foram feitas comparações entre mulheres brancas e negras quanto às características sociodemográficas e ao estadiamento, usando o teste qui-quadrado, e à sobrevivência em 10 anos, usando os métodos de Kaplan-Meier e regressão de Cox. Foram estimados para a variável raça/cor efeitos diretos e indiretos, mediados pelo estadiamento, com ajuste para a condição social da área de residência e idade, utilizando o modelo de respostas potenciais (contrafactual) e regressão múltipla de Cox. As mulheres negras residiam em setores censitários de menor renda, eram usuárias do setor público em maior proporção e foram diagnosticadas com estadiamentos mais avançados. A sobrevivência específica em 10 anos foi de 64,3% (IC95%: 60,0; 68,9), com diferença significativa entre brancas (69,5%; IC95%: 64,8; 74,6) e negras (44%; IC95%: 35,2; 55,1). Nos modelos múltiplos, ajustados para renda e idade, as negras tiveram pior prognóstico (HR = 2,09; IC95%: 1,76; 2,51), e a proporção mediada pelo estadiamento foi de 40% (IC95%: 37; 42). Há disparidade racial na sobrevivência do câncer de mama em 10 anos, mediada principalmente pelo estadiamento mais avançado da doença nas mulheres negras. Isso aponta para a necessidade de ampliar a cobertura e a qualidade do programa de rastreamento dessa doença e facilitar o acesso ao diagnóstico e tratamento precoces, com vistas à redução da iniquidade racial.

Impact of national cancer policies on cancer survival trends and socioeconomic inequalities in England, 1996-2013: population based study

OBJECTIVE

To assess the effectiveness of the NHS Cancer Plan (2000) and subsequent national cancer policy initiatives in improving cancer survival and reducing socioeconomic inequalities in survival in England.

DESIGN

Population based cohort study.

SETTING

England.

POPULATION

More than 3.5 million registered patients aged 15-99 with a diagnosis of one of the 24 most common primary, malignant, invasive neoplasms between 1996 and 2013.

MAIN OUTCOME MEASURES

Age standardised net survival estimates by cancer, sex, year, and deprivation group. These estimates were modelled using regression model with splines to explore changes in the cancer survival trends and in the socioeconomic inequalities in survival.

RESULTS

One year net survival improved steadily from 1996 for 26 of 41 sex-cancer combinations studied, and only from 2001 or 2006 for four cancers. Trends in survival accelerated after 2006 for five cancers. The deprivation gap observed for all 41 sex-cancer combinations among patients with a diagnosis in 1996 persisted until 2013. However, the gap slightly decreased for six cancers among men for which one year survival was more than 65% in 1996, and for cervical and uterine cancers, for which survival was more than 75% in 1996. The deprivation gap widened notably for brain tumours in men and for lung cancer in women.

CONCLUSIONS

Little evidence was found of a direct impact of national cancer strategies on one year survival, and no evidence for a reduction in socioeconomic inequalities in cancer survival. These findings emphasise that socioeconomic inequalities in survival remain a major public health problem for a healthcare system founded on equity.

Assessment of spatial variation in breast cancer-specific mortality using Louisiana SEER data

BACKGROUND

Previous studies suggest spatial differences in mortality for many types of cancer, including breast cancer. Identifying explanations for these spatial differences results in a better understanding of what leads to longer survival time.

METHODS

We used a Bayesian accelerated failure time model with spatial frailty terms to investigate potential spatial differences in breast cancer mortality following breast cancer diagnosis using 2000-2013 Louisiana SEER data.

RESULTS

There are meaningful spatial differences in breast cancer mortality across the parishes of Louisiana, even after adjusting for known demographic and clinical risk factors. For example, the average survival time of a woman diagnosed in Orleans parish was 1.51 times longer than that of a woman diagnosed in Terrebonne parish. Additionally, there is evidence to suggest shorter survival times in lower income parishes along the Red and Mississippi Rivers, as well as parishes with lower socioeconomic status, less access to care and fresh food, worse quality of care, and more workers in certain industries.

CONCLUSION

The addition of spatial frailties to account for an individual's geographic location is useful when analyzing breast cancer mortality data. Our findings suggest that survival following breast cancer diagnosis could potentially be improved if socioeconomic status differences were addressed, healthcare improved in quality and became more accessible, and certain industrial situations were improved for individuals diagnosed in parishes identified as having shorter average survival times.

Baseline characteristics, survival and direct costs associated to treatment of gastric cancer patients at the National Oncology Institute of Panama from 2012 to 2015: a hospital-based observational study

OBJECTIVES

Comprehensive epidemiological and economic studies of gastric cancer (GC) in Panama are limited. This study aims to evaluate the association between socioeconomic and clinical variables with survival, describe the survival outcomes according to clinical stage and estimate the direct costs associated to GC care in a Panamanian population with GC.

DESIGN AND SETTING

A retrospective observational study was conducted at the leading public institution for cancer treatment in Panama.

PARTICIPANTS

Data were obtained from 611 records of patients diagnosed with gastric adenocarcinoma (codes C16.0-C16.9 of the International Classification of Diseases 10th revision), identified between 1 January 2012 and 31 December 2015.

METHODS

Cox proportional hazards models were used to calculate HRs with 95%  CI to examine associations between the variables and survival. Kaplan-Meier curves were used to assess overall and stage-specific survival. Direct costs (based on 2015 US$) were calculated per patient using standard costs provided by the institution for hospital admission (occupied bed-days), radiotherapy, surgery and chemotherapy, yielding total and overall mean costs (OMC). A comparison of OMC between groups (sex, social security status, clinical stage) was performed applying the bootstrap method with a t-test of unequal variances.

RESULTS

An increased risk of dying was observed for patients without social security coverage (HR: 2.02; 95% CI 1.16 to 3.53), overlapping tumours (HR: 1.50; 95% CI 1.02 to 2.22), poorly differentiated tumours (HR: 2.27; 95% CI 1.22 to 4.22) and stage IV disease (HR: 5.54; 95% CI 3.38 to 9.08) (adjusted models). Overall 1-year survival rate was 41%. The estimated OMC of GC care per patient was 4259 US$. No statistically significant differences were found in OMC between groups.

CONCLUSIONS

Socioeconomic disparities influence GC outcomes and healthcare utilisation. Policies addressing healthcare disparities related to GC are needed, as well as in-depth studies evaluating barriers of access to GC-related services.