Breast cancer inequities between Māori and non-Māori women in Aotearoa/New Zealand

Ethnic differences in time to surgery for women with early stage breast cancer in Aotearoa/New Zealand: a population-based study

Background

This study evaluates whether there are ethnic differences in time to surgery in women with early-stage (1-3a) breast cancer in four NZ urban regions between 2000 and 2020 pre- and post- Faster Cancer Treatment (FCT) implementation, which was introduced to address inequities in cancer outcomes.

Methods

This retrospective analysis used Te Rēhita Mate Ūtaetae (Breast Cancer Foundation National Register), a prospectively maintained database of breast cancers from 2000 to 2020. Women with stage 3b, 3c, metastatic or bilateral cancers were excluded. Logistic regression models evaluated ethnic differences in time to surgery (≤31/>31 days as per FCT plan) with sequential adjustment for potential contributing factors (demographic, mode of diagnosis, tumour, treatment facility type and treatment). Subgroup analyses by pre- and post-FCT implementation date were undertaken.

Findings

Of the 16,365 women included, 74.1% were NZ European (NZE), 10.2% were Māori, 6.1% were Pacific, and 9.2% were Asian. Wāhine Māori (Māori women) and Pacific women were more likely to experience delays in surgery >31 days, compared to NZE (maximally adjusted OR: 1.18; 95% CI:1.05, 1.33 and OR:1.42; 95% CI:1.22, 1.65, respectively)-deprivation and treatment facility type contributed most to this. Wāhine Māori experienced delay in the public system only. The associations did not differ between the pre- and post- FCT periods.

Interpretation

Ethnic inequities exist with respect to time to surgery for women with early-stage breast cancer and these differences persist after FCT implementation.

Funding

LB is supported by the Richard Stewart scholarship, the Royal Australasian College of Surgeons and Oxford Population Health.

Ethnic inequities in use of breast conserving surgery and radiation therapy in Aotearoa/New Zealand: which factors contribute?

PURPOSE

Aotearoa/New Zealand (NZ) faces ethnic inequities with respect to breast cancer survival and treatment. This study establishes if there are ethnic differences in (i) type of surgery and (ii) receipt of radiotherapy (RT) following breast conserving surgery (BCS), among women with early-stage breast cancer in NZ.

METHODS

This analysis used Te Rēhita Mata Ūtaetae (Breast Cancer Foundation National Register), a prospectively maintained database of breast cancers from 2000 to 2020. Logistic regression models evaluated ethnic differences in type of surgery (mastectomy or BCS) and receipt of RT with sequential adjustment for potential contributing factors. Subgroup analyses by treatment facility type were undertaken.

RESULTS

Of the 16,228 women included, 74% were NZ European (NZE), 10.3% were Māori, 9.4% were Asian and 6.2% were Pacific. Over one-third of women with BCS-eligible tumours received mastectomy. Asian women were more likely to receive mastectomy than NZE (OR 1.62; 95% CI 1.39, 1.90) as were wāhine Māori in the public system (OR 1.21; 95% CI 1.02, 1.44) but not in the private system (OR 0.78; 95% CI 0.51, 1.21). In women undergoing BCS, compared to NZE, Pacific women overall and wāhine Māori in the private system were, respectively, 36 and 38% less likely to receive RT (respective OR 0.64; 95% CI 0.50, 0.83 and 0.62; 95% CI 0.39, 0.98).

CONCLUSION

A significant proportion of women with early-stage breast cancer underwent mastectomy and significant ethnic inequities exist. Recently developed NZ Quality Performance Indicators strongly encourage breast conservation and should facilitate more standardized and equitable surgical management of early-stage breast cancer.

Anti-racist interventions to reduce ethnic disparities in healthcare in the UK: an umbrella review and findings from healthcare, education and criminal justice

OBJECTIVES

To assess the evidence for anti-racist interventions which aim to reduce ethnic disparities in healthcare, with a focus on implementation in the UK healthcare system.

DESIGN

Umbrella review.

DATA SOURCES

Embase, Medline, Social Policy and Practice, Social Care Online and Web of Science were searched for publications from the year 2000 up to November 2023.

ELIGIBILITY CRITERIA

Only systematic and scoping reviews of anti-racist interventions reported in English were included. Reviews were excluded if no interventions were reported, no comparator interventions were reported or the study was primarily descriptive.

DATA EXTRACTION AND SYNTHESIS

A narrative synthesis approach was used to integrate and categorise the evidence on anti-racist interventions for healthcare. Quality appraisal (including risk of bias) was assessed using the AMSTAR-2 tool.

RESULTS

A total of 29 reviews are included in the final review. 26 are from the healthcare sector and three are from education and criminal justice. The most promising interventions targeting individuals include group-based health education and providing culturally tailored interventions. On a community level, participation in all aspects of care pathway development that empowers ethnic minority communities may provide an effective approach to reducing ethnic health disparities. Interventions to improve quality of care for conditions with disproportionately worse outcomes in ethnic minority communities show promise. At a policy level, structural interventions including minimum wage policies and integrating non-medical interventions such as housing support in clinical care has some evidence for improving outcomes in ethnic minority communities.

CONCLUSIONS

Many of the included studies were low or critically low quality due to methodological or reporting limitations. For programme delivery, different types of pathway integration, and providing a more person-centred approach with fewer steps for patients to navigate can contribute to reducing disparities. For organisations, there is an overemphasis on individual behaviour change and recommendations should include a shift in focus and resources to policies and practices that seek to dismantle institutional and systemic racism through a multilevel approach.

Cancer Screening Services: What Do Indigenous Communities Want? A Systematic Review

PURPOSE

Indigenous communities experience worse cancer outcomes compared with the general population partly because of lower cancer screening access. One-size-fits-all screening programs are unsuitable for reaching Indigenous communities. In this review, we summarize available evidence on the perspectives of these communities; with a view to informing the improvement of cancer screening services to achieve equitable access.

METHODS

We undertook a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the databases MEDLINE, Scopus, PubMed, and Google Scholar. The search terms used were "Indigenous community or Indigenous communities," "cancer screening," and "facilitators, enablers, desires, or needs." Qualitative studies published up to the August 30, 2022 investigating the perspectives of Indigenous communities on factors encouraging screening participation were included in the study. The included studies were reviewed and analyzed inductively by two independent reviewers, and key themes regarding indigenous access to cancer screening were then extracted.

RESULTS

A total of 204 unique articles were identified from the search. The title and abstracts of these studies were screened, and 164 were excluded on the basis of the exclusion and inclusion criteria. The full texts of the remaining 40 studies were examined and 18 were included in the review. Four key themes were identified pertaining to culturally tailored education and information dissemination, community involvement, positive relationships with health care providers, and individual empowerment and autonomy.

CONCLUSION

Improvements, on the basis of the key themes identified from this review, must be made at all levels of the health care system to achieve equitable screening participation in Indigenous communities. However, we recommend an investigation into the perspectives of the local Indigenous communities before the initiation of cancer screening programs.

Receipt of mastectomy and adjuvant radiotherapy following breast conserving surgery (BCS) in New Zealand women with BCS-eligible breast cancer, 2010-2015: an observational study focusing on ethnic differences

BACKGROUND

Women with early breast cancer who meet guideline-based criteria should be offered breast conserving surgery (BCS) with adjuvant radiotherapy as an alternative to mastectomy. New Zealand (NZ) has documented ethnic disparities in screening access and in breast cancer treatment pathways. This study aimed to determine whether, among BCS-eligible women, rates of receipt of mastectomy or radiotherapy differed by ethnicity and other factors.

METHODS

The study assessed management of women with early breast cancer (ductal carcinoma in situ [DCIS] and invasive stages I-IIIA) registered between 2010 and 2015, extracted from the recently consolidated New Zealand Breast Cancer Registry (now Te Rēhita Mate Ūtaetae NZBCF National Breast Cancer Register). Specific criteria were applied to determine women eligible for BCS. Uni- and multivariable analyses were undertaken to examine differences by demographic and clinicopathological factors with a primary focus on ethnicity (Māori, Pacific, Asian, and Other; the latter is defined as NZ European, Other European, and Middle Eastern Latin American and African).

RESULTS

Overall 22.2% of 5520 BCS-eligible women were treated with mastectomy, and 91.1% of 3807 women who undertook BCS received adjuvant radiotherapy (93.5% for invasive cancer, and 78.3% for DCIS). Asian ethnicity was associated with a higher mastectomy rate in the invasive cancer group (OR 2.18; 95%CI 1.72-2.75), compared to Other ethnicity, along with older age, symptomatic diagnosis, advanced stage, larger tumour, HER2-positive, and hormone receptor-negative groups. Pacific ethnicity was associated with a lower adjuvant radiotherapy rate, compared to Other ethnicity, in both invasive and DCIS groups, along with older age, symptomatic diagnosis, and lower grade tumour in the invasive group. Both mastectomy and adjuvant radiotherapy rates decreased over time. For those who did not receive radiotherapy, non-referral by a clinician was the most common documented reason (8%), followed by patient decline after being referred (5%).

CONCLUSION

Rates of radiotherapy use are high by international standards. Further research is required to understand differences by ethnicity in both rates of mastectomy and lower rates of radiotherapy after BCS for Pacific women, and the reasons for non-referral by clinicians.

Supporting implementation of interventions to address ethnicity-related health inequities: frameworks, facilitators and barriers - a scoping review protocol

INTRODUCTION

Health inequities are differences in health between groups of people that are avoidable, unfair and unjust. Achieving equitable health outcomes requires approaches that recognise and account for the differences in levels of advantage between groups. Implementation science, which studies how to translate evidence-based interventions into routine practice, is increasingly recognised as an approach to address health inequities by identifying factors and processes that enable equitable implementation of interventions. This article describes the protocol for a scoping review of the literature relating to the equitable implementation of interventions, focusing on ethnicity-related health inequities. The scoping review aims to identify equity-focused implementation science theories, models and frameworks (TMFs) and to synthesise and analyse the evidence relating to the factors that aid or inhibit equitable implementation of health interventions.

METHODS AND ANALYSIS

The scoping review is guided by the methodology developed by Arksey and O'Malley and enhanced by Levac and colleagues. Relevant literature will be identified by searching electronic databases, grey literature, hand-searching key journals and searching the reference lists and citations of studies that meet the inclusion criteria. We will focus on literature published from 2011 to the present. Titles, abstracts and full-text articles will be screened independently by two researchers; any disagreements will be resolved through discussion with another researcher. Extracted data will be summarised and analysed to address the scoping review aims.

ETHICS AND DISSEMINATION

The scoping review will map the available literature on equity-focused implementation science TMFs and the facilitators and barriers to equitable implementation of interventions. Ethical approval is not required. Dissemination of the results of the review will include publications in peer-review journals and conference and stakeholder presentations. Findings from the review will support those implementing interventions to ensure that the implementation pathway and processes are equitable, thereby improving health outcomes and reducing existing inequities.

Risk factors at five-year survival in grade 3 breast cancer: a retrospective observational study of the New Zealand population

BACKGROUND

Breast cancer is the most common cancer in New Zealand, with approximately 3000 new registrations annually, affecting one in nine women and resulting in more than 600 deaths. This study analyzed data of patients with selected prognostic factors of Nottingham grade 3 tumors over a specified five-year period. The study aimed to identify factors that result in differential survival in the female, New Zealand population.

METHOD

This is an observational, retrospective cohort study of prospectively collected data from New Zealand Breast Cancer Register. The selected period of 1st January 2011 to 31st, December 2015 allowed a consistent overlap for a national five-year data of grade 3 breast cancer in New Zealand. Mortality was carried out using univariate Fine-Gray competing risk statistical models.

RESULTS

This study showed that women in the older age group (> 70 years) had higher five-year mortality risk (HR: 1.7, 95% CI: 0.9-3.0, p = 0.053). Hormonal receptor analysis showed that ER positive, PR negative, and ER negative, PR negative subjects were at increased risk (HR = 3.5, 95% CI 2.3-5.4, p < 0.001) and (HR = 2.6, 95% CI, 1.8-3.9, p < 0.001) respectively. Molecular subtypes Triple Negative Breast Cancer and Luminal B subjects were at increased risk (HR = 3.0, 95% CI, 1.8-4.7, p < 0.001 and (HR = 3.3, 95% CI, 1.7-6.3, p < 0.001) respectively. HER2 enriched subjects were at a higher, but not significant, risk of five-year mortality compared to luminal A (HR = 1.6, 95% CI, 0.8-3.0, p = 0.10). NZ Europeans were at increased risk (HR = 1.7, 95% CI, 0.8-3.2, p = 0.11), with the highest Cumulative Incidence Function CIF, the largest proportion of HER2 enriched and TNBC across ethnicities.; however, Pacific Islanders experienced the highest HER2 CIF.

CONCLUSION

The survival rates for grade 3 breast cancer vary across the selected prognostic factors and ethnicity. The results of this study make an initial contribution to the understanding of grade 3 breast cancer in the New Zealand population.

Surgical Services for Breast Cancer Patients in Australia, is There a Gap for Aboriginal and/or Torres Strait Islander Women?

BACKGROUND

Breast cancer is the most commonly diagnosed cancer in Aboriginal and/or Torres Strait Islander women. When compared to other Australians, Aboriginal and/or Torres Strait Islander women have a higher breast cancer mortality rate. This systematic literature review examined disparities in breast cancer surgical access and outcomes for Aboriginal and/or Torres Strait Islander women.

METHODS

This systematic literature review, following the PRISMA guidelines, compared measures of breast cancer surgical care for Aboriginal and/or Torres Strait Islander people and other Australians.

RESULTS

The 13 included studies were largely state-based retrospective reviews of data collected prior to the year 2012. Eight studies reported more advanced breast cancer presentation among Aboriginal and/or Torres Strait Islander women. Despite the increased distance to a multidisciplinary, specialist team, there were no disparities in seeing a surgeon, or in the time from diagnosis to surgical treatment. Two studies reported disparities in the receipt of surgery and two reported no variations. Three studies reported disparities in the receipt of mastectomy versus breast conserving surgery, whilst four studies reported no variations. No studies examined postoperative surgical outcomes.

CONCLUSIONS

Aboriginal and/or Torres Strait Islander women present with more advanced breast cancer. There may be disparities in the receipt of surgery and the type of surgery. However, the metrics tested were not related to optimal care guidelines, and the databases utilised contain limited data on individual factors contributing to surgical care decisions. It is therefore difficult to determine whether the reported differences in the receipt of surgical care reflect disparate or appropriate care.

Prostate cancer outcomes disparities: Population survival analysis in an ethnically diverse nation

BACKGROUND

Prostate cancer represents a significant health burden on New Zealand men. There are increasing concerns regarding inequities in prostate cancer morbidity and mortality among the different ethnic groups in New Zealand. This study aims to assess ethnic differences in survival outcomes among men newly diagnosed with prostate cancer.

MATERIALS AND METHODS

The analyzed cohort included 42,563 men, 40 years or older, diagnosed with prostate cancer from January 1st, 2000 to January 1st, 2016. Overall and cancer-specific survivals were estimated for the main ethnic groups in New Zealand namely: Māori (indigenous), Pacific, Asian, and European. Hazard ratio (HR) of death from prostate cancer was calculated with Fine-Gray competing risk regression, while adjusting for age, socioeconomic deprivation, year of cancer diagnosis, residential status, presence of urology service, and cancer grade at diagnosis.

RESULTS

Among all ethnic groups, Māori participants consistently had worst survival outcomes. At 15-year follow-up, the overall cumulative survival probabilities were 39.8%, 43.6%, 63.3%, and 46.5%, for Māori, Pacific, Asian and European men, respectively. In the same order, cancer-specific survivals were 62.7%, 64.3%, 79.8% and 72.0%. Māori men had 43% higher risk of dying from prostate cancer when compared to Europeans. This persisted following adjustments in the multivariable model (adjusted HR = 1.44, [95% CI: 1.29-1.61], P< 0.001). Conversely, differences in sociodemographic and cancer characteristics between Pacific and European men could explain the higher mortality risk in the former group (adjusted HR = 1.00, [95% CI: 0.84-1.19], P= 0.990).

CONCLUSIONS

Significant ethnic disparities in prostate cancer survival outcomes are currently present in New Zealand. Several explanations have been proposed to account for this observation including differences in comorbidities, healthcare access and cancer grade at diagnosis.

The views of New Zealand general practitioners and patients on a proposed risk assessment and communication tool: a qualitative study using Normalisation Process Theory

BACKGROUND

Communicating risks of medication harm and obtaining informed consent is difficult due to structural barriers, language and cultural practices, bias and a lack of resources appropriately tailored for the health literacy of most patients. A decision support tool was proposed to alert prescribers of risk and provide tailored information for patients to facilitate informed decision-making with patients and their whānau (family) around medication use. Patient and prescriber co-design was used to ensure the tool was designed to best meet the needs of end-users and avoid increasing health inequity. This paper describes the first stage of the co-design process.

METHOD

Normalisation Process Theory (NPT) was used to prospectively evaluate the tool. Semi-structured interviews were held with fifteen patients (five Māori, five Pasifika and five NZ European) and nine general practitioners (two Māori and seven European).

RESULTS

Three themes were identified, which related to the three NPT concepts most relevant to developing the tool. Theme 1 (coherence: meaning and sense making by participants) explored participants' understanding of prescribing safety, medication harm and risk, which is based on experience. Patients want as much information as possible about their medications and risk, but doctors find it difficult to communicate that information. Theme 2 related to the NPT concept of cognitive participation (commitment and engagement by participants) explored what participants thought about a prescribing decision support tool. Participants were cautiously optimistic, but worried about potential harm arising from its use. They also identified requirements for the tool and features to avoid. Theme 3 describes the collective action required for successful implementation of the tool; namely, culturally safe and trustworthy doctor-patient relationships.

CONCLUSION

Patients and general practitioners provided different perspectives when prospectively evaluating the proposed risk assessment and communication tool. This co-design research identified important pre-requisites for the tool and features to avoid and novel ideas for the proposed tool. Overall participants supported the development of the proposed risk assessment and communication tool, but identified the important role that doctor-patient relationships would play to ensure successful implementation. The use of Māori and Pacific languages in the proposed tool may enhance engagement and understanding.

Outcomes in different ethnic groups of New Zealand patients with screen-detected vs. non-screen-detected breast cancer

Objective

To compare characteristics and survival of New Zealand European, Māori, and Pacific women with screen-detected vs. non-screen-detected breast cancer.

Methods

Women aged 45–69 diagnosed with invasive breast cancer between January 2005 and May 2013 were identified from the Waikato and Auckland Breast Cancer Registries. Patient demographics and tumour characteristics were described by detection mode and ethnicity. Kaplan–Meier method was used to estimate the five-year breast cancer-specific survival of women with stage I–III breast cancer by ethnicity and detection mode.

Results

Women with screen-detected cancers were older, had smaller tumours, fewer stage IV (0.8% vs. 7.6%), fewer high grade (16.8% vs. 39.0%), and fewer lymph node positive diseases (26.3% vs. 51.5%) than women with non-screen-detected cancers. There were more Luminal A (70.0% vs. 54.0%), fewer human epidermal growth factor receptor 2 positive non-Luminal (4.4% vs. 8.8%), and fewer triple negative cases (7.0% vs. 13.8%) in screen-detected than non-screen-detected cancers. If not screen detected, 22.7% of breast cancers in Pacific women were stage IV compared with 2.4% if screen detected. If not screen detected, the five-year breast cancer-specific survival was 91.1% for New Zealand European women, 84.2% for Māori women, and 80.2% for Pacific women (p-value <0.001). For screen-detected breast cancer, survival between different ethnic groups was similar.

Conclusions

Breast cancers detected through screening are diagnosed at an earlier stage and have a greater proportion of subtypes, with better outcome. Variations in survival for Māori and Pacific women are only found in women with non-screen-detected breast cancer.

The characteristics, management and outcomes of older women with breast cancer in New Zealand

The aim of this study was to understand the characteristics of older women with breast cancer and to describe the current patterns of treatment and outcomes. The study included data from the combined Auckland and Waikato breast cancer registers, which hold information for 12, 372 women diagnosed with stage I-IV breast cancer between June 2000 and May 2013. Of these women, 2671 (21.6%) were over 70 years of age. Patient characteristics, treatment type and survival were compared across four-year age groups (70-74, 75-79, 80-84, 85+) and hormone receptor status. Of the women aged over 70 years, 2485 (93.0%) had stage I-III disease. Increasing age was significantly associated with decreasing use of surgery, adjuvant radiotherapy, endocrine therapy and chemotherapy, even after adjustment for stage and level of co-morbidity. Nine hundred and one women (33.7%) had co-morbidities at the time of diagnosis. The 5-year breast cancer-specific survival rate for women aged 70-74 and that for women aged 75-79 were similar, but was worse in women aged over 80. Generally, older women are treated as per guidelines, although chemotherapy may be under-used. However, age is a significant factor influencing whether women are treated or not.

Breast Cancer in Australian Indigenous Women: Incidence, Mortality, and Risk Factors

The Indigenous people of Australia face significant health gaps compared with the general population, with lower life expectancies, higher rates of death, and chronic illness occurring more often than in non-indigenous Australians. Cancer is the second largest contributor to the burden of disease with breast cancer being the most common invasive cancer diagnosed for females. Despite a lower breast cancer incidence compared with non-indigenous women, fatalities occur at an elevated rate and breast cancers have an earlier age of onset. For indigenous women there are also more advanced and distant tumours at diagnosis, fewer hospitalisations for breast cancer, and lower participation in breast screening. Concomitantly there are demographic, socio-economic and lifestyle factors associated with breast cancer risks that are heavily represented within Indigenous communities. The aim of this two-part narrative review is to examine the available evidence on breast cancer and its risk factors in Australian Indigenous women. Part One presents a summary of the latest incidence, survival and mortality data. Part Two presents the risk factors most strongly associated with breast cancer including age, place of residence, family risk, genetics, reproductive history, tobacco use, alcohol intake, physical activity, participation in screening and breast density. With increasing emphasis on personalized health care, a clear understanding of breast cancer incidence, survival, mortality, and causal agents within the Indigenous population is required if breast cancer prevention and management is to be optimized for Indigenous Australians.

Mammography service screening and breast cancer mortality in New Zealand: a National Cohort Study 1999-2011

Background:

This breast cancer mortality evaluation of service screening mammography in New Zealand, the first since commencement of screening in 1999, applies to the 1999–2011 diagnostic period. Individual-level linked information on mammography screening, breast cancer diagnosis and breast cancer mortality is used to analyse differences in breast cancer mortality according to participation in organised screening mammography, as provided by BreastScreen Aotearoa (BSA).

Methods:

Women were followed from the time they became eligible for screening, from age 50 years (1999–2004) and 45 years (⩾2004). Breast cancer mortality from cancers diagnosed during the screening period from 1999 to 2011 (n=4384) is examined in relation to individual screening participation or non-participation during preceding person-years of follow-up from the time of screening eligibility. To account for changes from never- to ever-screened status, breast cancer mortality is calculated for each year in relation to prior accumulated time of participation and non-participation in screening. Breast cancer mortality is also examined in regularly screened women (screened ⩾3 times and mean screening interval ⩽30 months), and irregularly screened women compared with never-screened women. Statistical analyses are by negative binomial and Poisson regression with adjustment for age and ethnic group (Māori, Pacific women) in a repeated-measures analysis. Relative risks for breast cancer mortality compared with never-screened women, are adjusted also for screening selection bias, to indicate the extent of breast cancer mortality reduction in a population offered and not offered mammography screening. Prognostic indicators at diagnosis of breast cancer are also compared between different screening participation groups, including by grade of tumour, extent of disease (spread), multiple tumour status and maximum tumour size using χ² statistics, t-tests and two-sample median tests.

Results:

For 1999–2011, after adjusting for age and ethnicity, breast cancer mortality in ever-screened women is estimated to be 62% (95% CI: 51–70) lower than in never-screened women. After further adjustment for screening selection bias, the mortality reduction in NZ is estimated to be 29% (95% CI: 20–38) at an average screening coverage of 64% for 2001–2011, and 34% (95% CI: 25–43) for recent screening coverage (2012–13, 71%). For irregularly screened women, the mortality reduction is estimated to be 31% (95% CI: 21–40), and 39% (95% CI: 22–52) in regularly screened women compared with never-screened women, after adjusting for age, ethnicity and screening selection bias (using recent 2012–2013 screening coverage of 71%). Ever-screened women diagnosed with breast cancer have more favourable prognostic indicators than never-screened women, with a higher proportion of localised cancer (63 compared with 46%), a higher proportion with a well-differentiated tumour (30 compared with 18%), lower risk of multiple tumours (RR=0.48) and smaller median tumour size (15 mm compared with 20 mm)—all differences are statistically significant (P<0.0001).

Conclusions:

This is the first total population cohort study of an established nation-wide screening mammography programme using individual-level information on screening participation and mortality outcomes from breast cancer. The findings are in accord with other mammography screening service evaluations and with randomised trials of mammography screening.

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

Background

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

Methods

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

Results

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

Conclusions

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