Breast cancer incidence trends in deprived and affluent Scottish women

Socioeconomic disparities in cancer incidence and mortality in England and the impact of age-at-diagnosis on cancer mortality

Background

We identify socioeconomic disparities by region in cancer morbidity and mortality in England for all-cancer and type-specific cancers, and use incidence data to quantify the impact of cancer diagnosis delays on cancer deaths between 2001–2016.

Methods and findings

We obtain population cancer morbidity and mortality rates at various age, year, gender, deprivation, and region levels based on a Bayesian approach. A significant increase in type-specific cancer deaths, which can also vary among regions, is shown as a result of delay in cancer diagnoses. Our analysis suggests increase of 7.75% (7.42% to 8.25%) in female lung cancer mortality in London, as an impact of 12-month delay in cancer diagnosis, and a 3.39% (3.29% to 3.48%) increase in male lung cancer mortality across all regions. The same delay can cause a 23.56% (23.09% to 24.30%) increase in male bowel cancer mortality. Furthermore, for all-cancer mortality, the highest increase in deprivation gap happened in the East Midlands, from 199 (186 to 212) in 2001, to 239 (224 to 252) in 2016 for males, and from 114 (107 to 121) to 163 (155 to 171) for females. Also, for female lung cancer, the deprivation gap has widened with the highest change in the North West, e.g. for incidence from 180 (172 to 188) to 272 (261 to 282), whereas it has narrowed for prostate cancer incidence with the biggest reduction in the South West from 165 (139 to 190) in 2001 to 95 (72 to 117) in 2016.

Conclusions

The analysis reveals considerable disparities in all-cancer and some type-specific cancers with respect to socioeconomic status. Furthermore, a significant increase in cancer deaths is shown as a result of delays in cancer diagnoses which can be linked to concerns about the effect of delay in cancer screening and diagnosis during the COVID-19 pandemic. Public health interventions at regional and deprivation level can contribute to prevention of cancer deaths.

Cancer morbidity trends and regional differences in England-A Bayesian analysis

Reliable modelling of the dynamics of cancer morbidity risk is important, not least due to its significant impact on healthcare and related policies. We identify morbidity trends and regional differences in England for all-cancer and type-specific incidence between 1981 and 2016. We use Bayesian modelling to estimate cancer morbidity incidence at various age, year, gender, and region levels. Our analysis shows increasing trends in most rates and marked regional variations that also appear to intensify through time in most cases. All-cancer rates have increased significantly, with the highest increase in East, North West and North East. The absolute difference between the rates in the highest- and lowest-incidence region, per 100,000 people, has widened from 39 (95% CI 33-45) to 86 (78-94) for females, and from 94 (85-104) to 116 (105-127) for males. Lung cancer incidence for females has shown the highest increase in Yorkshire and the Humber, while for males it has declined in all regions with the highest decrease in London. The gap between the highest- and lowest-incidence region for females has widened from 47 (42-51) to 94 (88-100). Temporal change in in bowel cancer risk is less manifested, with regional heterogeneity also declining. Prostate cancer incidence has increased with the highest increase in London, and the regional gap has expanded from 33 (30-36) to 76 (69-83). For breast cancer incidence the highest increase has occurred in North East, while the regional variation shows a less discernible increase. The analysis reveals that there are important regional differences in the incidence of all-type and type-specific cancers, and that most of these regional differences become more pronounced over time. A significant increase in regional variation has been demonstrated for most types of cancer examined here, except for bowel cancer where differences have narrowed.

Higher breast cancer prevalence associated with higher socioeconomic status in the South Korean population; Has it resulted from overdiagnosis?

Recently, breast cancer prevalence has increased in South Korea. In this study, we investigated the correlation between breast cancer prevalence and socioeconomic status. This study enrolled 27,331 people who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) IV–VI (2007–2015). In addition, we obtained data from the Korean Statistical Information Service (KSIS) on the breast cancer age-standardized incidence rate (AIR), the age-standardized mortality rate (AMR), the number of women screened, and the number of newly diagnosed patients. The KHANES data showed that breast cancer prevalence was significantly associated with educational level (odds ratio [OR], 2.02; 95% confidence interval [CI], 1.08–3.77 for 10–12 vs. ≤ 6 years of education, and OR, 2.36; 95% CI, 1.10–5.06 for ≥ 13 vs. ≤ 6 years of education). However, there was no significant association of breast cancer prevalence with monthly household income. In a separate analysis of the AIR, AMR, and number of women screened for breast cancer, the AIR increased with the number of women screened, whereas the AMR did not. Furthermore, the number of newly diagnosed patients in all age groups increased over time. The present results demonstrate that the recently increased breast cancer prevalence documented in South Korea may be attributable to earlier detection rather than to a real increase in prevalence, and that breast cancer may be overdiagnosed.

The impact of socio-economic deprivation on incidence, treatment and mortality from prostate cancer in England, 1990–2010

Objective:

To explore any association between socio-economic deprivation and prostate cancer diagnosis and/or treatment.

Patients and methods:

Data was extracted as follows: We gained the incident cases and staging from the National Cancer Data Repository, survival from the Cancer Information System, mortality from the Office for National Statistics, treatment data from Hospital Episode Statistics and National Clinical Analysis and Specialised Applications Team. Our analysis regarding socio-economic deprivation was controlled for age distribution.

Results:

We recorded 518,453 diagnoses of prostate cancer; 174,579 prostate cancer deaths; 33,889 prostatectomies and 21,351 radiotherapy treatments. Incidence is increasing in all groups, but the highest is amongst the least deprived. Mortality is decreasing, with survival consistently better in the least deprived. Prostatectomies are more frequent in the least deprived; however, this gap is narrowing.

Conclusions:

Prostate cancer incidence, survival and treatment are associated with socio-economic deprivation. Prostatectomy rates show a decrease in the gap of inequality. Multiple potential confounding factors, such as rates of prostate specific antigen (PSA) testing and access to health care are associated with socio-economic deprivation. The unifying influences of Improving Outcomes Guidance and the National Treatment Guidelines are intended to counteract the above inequalities. Particularly in prostate cancer, where long-term gain depends on multiple factors, individualised treatment decisions are paramount.

Linking of primary care records to census data to study the association between socioeconomic status and cancer incidence in Southern Europe: a nation-wide ecological study

BACKGROUND

Area-based measures of economic deprivation are seldom applied to large medical records databases to establish population-scale associations between deprivation and disease.

OBJECTIVE

To study the association between deprivation and incidence of common cancer types in a Southern European region.

METHODS

Retrospective ecological study using the SIDIAP (Information System for the Development of Research in Primary Care) database of longitudinal electronic medical records for a representative population of Catalonia (Spain) and the MEDEA index based on urban socioeconomic indicators in the Spanish census. Study outcomes were incident cervical, breast, colorectal, prostate, and lung cancer in 2009-2012. The completeness of SIDIAP cancer recording was evaluated through linkage of a geographic data subset to a hospital cancer registry. Associations between MEDEA quintiles and cancer incidence was evaluated using zero-inflated Poisson regression adjusted for sex, age, smoking, alcoholism, obesity, hypertension, and diabetes.

RESULTS

SIDIAP sensitivity was 63% to 92% for the five cancers studied. There was direct association between deprivation and lung, colorectal, and cervical cancer: incidence rate ratios (IRR) 1.82 [1.64-2.01], IRR 1.60 [1.34-1.90], IRR 1.22 [1.07-1.38], respectively, comparing the most deprived to most affluent areas. In wealthy areas, prostate and breast cancers were more common: IRR 0.92 [0.80-1.00], IRR 0.91 [0.78-1.06]. Adjustment for confounders attenuated the association with lung cancer risk (fully adjusted IRR 1.16 [1.08-1.25]), reversed the direction of the association with colorectal cancer (IRR 0.90 [0.84-0.95]), and did not modify the associations with cervical (IRR 1.27 [1.11-1.45]), prostate (0.74 [0.69-0.80]), and breast (0.76 [0.71-0.81]) cancer.

CONCLUSIONS

Deprivation is associated differently with the occurrence of various cancer types. These results provide evidence that MEDEA is a useful, area-based deprivation index for analyses of the SIDIAP database. This information will be useful to improve screening programs, cancer prevention and management strategies, to reach patients more effectively, particularly in deprived urban areas.

Desigualdades socioeconômicas na incidência e mortalidade por câncer: revisão de estudos ecológicos, 1998-2008

INTRODUÇÃO: Desigualdades socioeconômicas se manifestam na incidência e mortalidade por neoplasias malignas. Estudos ecológicos representam abordagem essencial em epidemiologia e podem contribuir na investigação dos determinantes sociais dos eventos em saúde. OBJETIVO: Investigar associações entre nível socioeconômico e incidência e mortalidade por câncer e seus tipos, através de revisão de estudos ecológicos. Definir a real importância desempenhada pelos estudos ecológicos na investigação dessa relação. MÉTODO: As principais bases de dados regionais e internacionais foram pesquisadas na seleção de artigos em português, espanhol e inglês, publicados entre 1998 e 2008. RESULTADOS: 32 estudos elegíveis foram incluídos. Verificou-se associação positiva e consistente do nível socioeconômico da área de residência com incidência de câncer de próstata e mortalidade pelo de cólon nos homens, e com incidência e mortalidade por câncer de mama e mortalidade pelo de cólon nas mulheres. Associação consistente e negativa foi encontrada para incidência e mortalidade por cânceres de esôfago e estômago, para incidência dos de cólon e pulmão e mortalidade pelos de laringe e cavidade oral, nos homens, e para incidência e a mortalidade pelos de esôfago, estômago e colo uterino e para incidência dos de cólon e pulmão, nas mulheres. CONCLUSÃO: Apesar da presença de efeito residual de área e de viés relacionado à medida agregada de nível socioeconômico, estudos ecológicos podem ser eficientemente utilizados na mensuração das desigualdades socioeconômicas em câncer. Uso de pequenas unidades geográficas e de dados de registros de câncer em países em desenvolvimento pode contribuir para melhor conhecimento de suas desigualdades em saúde.

Identifying at-risk communities for action on cancer prevention: a case study in new brunswick (Canada) communities

Health statistics reported by large geographic area such as province, state, county or health region offer little insight into disease conditions at the community level where people live and work, where occupational and environmental exposures occur, and where industrial emissions are often concentrated. This study investigated overall patterns of cancer incidence and socioeconomic status (SES) among 14 communities in the province of New Brunswick (Canada). A multivariate ordination technique, hierarchical clustering, and permutation procedures were used to identify and test significance of community clusters and whether the overall pattern of SES was correlated with patterns of cancer among communities. Communities with significantly high or significantly low overall rates of cancers were identified, patterns that were not related to SES. The potential influence of age, small populations, diagnostic screening, smoking and environmental risk factors contributing to locally elevated cancer rates are discussed. Cancer incidence reported at smaller spatial scales provides health officials and researchers with a basis for identifying communities potentially at-risk and aids in the development of appropriate community-based risk reduction actions and cancer prevention.

Ethnic and socioeconomic trends in breast cancer incidence in New Zealand

BACKGROUND

Breast cancer incidence varies between social groups, but differences have not been thoroughly examined in New Zealand. The objectives of this study are to determine whether trends in breast cancer incidence varied by ethnicity and socioeconomic position between 1981 and 2004 in New Zealand, and to assess possible risk factor explanations.

METHODS

Five cohorts of the entire New Zealand population for 1981-86, 1986-1991, 1991-1996, 1996-2001, and 2001-2004 were created, and probabilistically linked to cancer registry records, allowing direct determination of ethnic and socioeconomic trends in breast cancer incidence.

RESULTS

Breast cancer rates increased across all ethnic and socioeconomic groups between 1981 and 2004. Māori women consistently had the highest age standardised rates, and the difference between Māori and European/Other women increased from 7% in 1981-6 to 24% in 2001-4. Pacific and Asian women had consistently lower rates of breast cancer than European/Other women over the time period studied (12% and 28% lower respectively when pooled over time), although young Pacific women had slightly higher incidence rates than young European/other women. A gradient between high and low income women was evident, with high income women having breast cancer rates approximately 10% higher and this difference did not change significantly over time.

CONCLUSIONS

Differences in breast cancer incidence between European and Pacific women and between socioeconomic groups are explicable in terms of known risk factors. However no straightforward explanation for the relatively high incidence amongst Māori is apparent. Further research to explore high Māori breast cancer rates may contribute to reducing the burden of breast cancer amongst Māori women, as well as improving our understanding of the aetiology of breast cancer.

Social variations in access to hospital care for patients with colorectal, breast, and lung cancer between 1999 and 2006: retrospective analysis of hospital episode statistics

OBJECTIVES

To determine the extent to which type of hospital admission (emergency compared with elective) and surgical procedure varied by socioeconomic circumstances, age, sex, and year of admission for colorectal, breast, and lung cancer.

DESIGN

Repeated cross sectional study with data from individual patients, 1 April 1999 to 31 March 2006.

SETTING

Hospital episode statistics (HES) dataset.

PARTICIPANTS

564 821 patients aged 50 and over admitted with a diagnosis of colorectal, breast, or lung cancer.

MAIN OUTCOME MEASURES

Proportion of patients admitted as emergencies, and the proportion receiving the recommended surgical treatment.

RESULTS

Patients from deprived areas, older people, and women were more likely to be admitted as emergencies. For example, the adjusted odds ratio for patients with breast cancer in the least compared with most deprived fifth of deprivation was 0.63 (95% confidence interval 0.60 to 0.66) and the adjusted odds ratio for patients with lung cancer aged 80-89 compared with those aged 50-59 was 3.13 (2.93 to 3.34). There were some improvements in disparities between age groups but not for patients living in deprived areas over time. Patients from deprived areas were less likely to receive preferred procedures for rectal, breast, and lung cancer. These findings did not improve with time. For example, 67.4% (3529/5237) of patients in the most deprived fifth of deprivation had anterior resection for rectal cancer compared with 75.5% (4497/5959) of patients in the least deprived fifth (1.34, 1.22 to 1.47). Over half (54.0%, 11 256/20 849) of patients in the most deprived fifth of deprivation had breast conserving surgery compared with 63.7% (18 445/28 960) of patients in the least deprived fifth (1.21, 1.16 to 1.26). Men were less likely than women to undergo anterior resection and lung cancer resection and older people were less likely to receive breast conserving surgery and lung cancer resection. For example, the adjusted odds ratio for lung cancer patients aged 80-89 compared with those aged 50-59 was 0.52 (0.46 to 0.59). Conclusions Despite the implementation of the NHS Cancer Plan, social factors still strongly influence access to and the provision of care.

Is the biology of breast cancer changing? A study of hormone receptor status 1984-1986 and 1996-1997

Using archived tumours, those from 1984–1986 and 1996–1997 underwent immunohistochemistry for hormone receptors and grade analysis. A significant shift towards more ER-positive and low-grade disease was found; this appears to reflect screening practices, but could still influence survival.

Disparities in breast cancer incidence across racial/ethnic strata and socioeconomic status: a systematic review

OBJECTIVES

A higher incidence of breast cancer has been reported both in white women and women of higher socioeconomic status (SES) compared to women of other races and lower SES, respectively. We explored whether differences in SES can account for disparities in breast cancer incidence between races.

METHODS

We identified several studies published between 1990 and 2007 that addressed disparities in breast cancer incidence across racial and socioeconomic strata. For each study, we calculated incidence rate ratios (IRRs) for breast cancer incidence in the highest strata to lowest strata of SES for white, black, Hispanic and Asian/Pacific-Islander populations. We then used these IRRs to compare trends in SES and breast cancer incidence between races and across studies.

RESULTS

The studies we identified revealed that the magnitude of the disparity in breast cancer incidence between races decreases with increasing SES. While individual census-tract based studies' methods of assessing the association between SES and breast cancer incidence did not identify consistent trends between races, adjustment for risk factors closely correlated with SES eliminated the statistical differences in breast cancer incidence between women of white, Hispanic and Asian/Pacific-Islander, but not black, ethnicity.

CONCLUSION

We found that racial differences in breast cancer incidence can largely be accounted for by ethnic differences in SES among white, Hispanic and Asian/Pacific-Islander women, but not between these populations and black women. We further highlight important differences in methodology between previously published studies that may account for their disparate findings.