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

Abstract

Māori women have one of the highest incidences of breast cancer in the world. This high incidence is generally unexplained although higher rates of obesity and alcohol intake are modifiable risk factors that may be important. Māori women are less likely to attend mammographic breast screening and are likely to be diagnosed with more advanced disease. This is one of the reasons for the excess mortality. Another factor is differences in the treatment pathway. Māori women are more likely to experience delay in receiving treatment, are less likely to receive radiotherapy, are more likely to be treated with a mastectomy and are less likely to adhere to long-term adjuvant endocrine therapy. However, genetic factors in Māori women do not seem to impact significantly on mortality. This review looks at the inequity between Māori and non-Māori women and addresses the causes. It proposes ways of reducing inequity through primary prevention, increased participation in breast screening and greater standardisation of the treatment pathway for women newly diagnosed with breast cancer. We believe that health system improvements will decrease barriers to health care participation for Māori women and suggest that further research into identifying and modifying obstacles within health systems is required.

Variations in outcomes for Indigenous women with breast cancer in Australia: A systematic review

“…For example, Indigenous women from Canada (Nishri et al, 2015) and the United States (DeSantis et al, 2014;Javid et al, 2014) have poorer survival while having lower incidence rates than their non-Indigenous counterparts while Maori women have poorer survival (and higher incidence rates) than non-Maori women in New Zealand (Lawrenson et al, 2016). For example, Indigenous women from Canada (Nishri et al, 2015) and the United States (DeSantis et al, 2014;Javid et al, 2014) have poorer survival while having lower incidence rates than their non-Indigenous counterparts while Maori women have poorer survival (and higher incidence rates) than non-Maori women in New Zealand (Lawrenson et al, 2016).…”

“…However, these benefits have not been experienced evenly across all population groups with consistently poorer survival for rural, remote and socioeconomically disadvantaged women (Aarts, Voogd, Duijm, Coebergh, & Louwman, 2011;AIHW, 2012a, b;Singh, Williams, Siahpush, & Mulhollen, 2011) and among Indigenous/ethnic minority groups (Dachs et al, 2008;DeSantis, Ma, Bryan, & Jemal, 2014;Javid et al, 2014;Lawrenson et al, 2016;Nishri, Sheppard, Withrow, & Marrett, 2015).…”

“…Inequalities also exist in other Indigenous populations. For example, Indigenous women from Canada (Nishri et al, 2015) and the United States (DeSantis et al, 2014;Javid et al, 2014) have poorer survival while having lower incidence rates than their non-Indigenous counterparts while Maori women have poorer survival (and higher incidence rates) than non-Maori women in New Zealand (Lawrenson et al, 2016). International studies have also consistently reported variations along the breast cancer continuum of care (such as screening, diagnosis and treatment) between Indigenous and non-Indigenous women (Javid et al, 2014;Kolahdooz et al, 2014;Lawrenson et al, 2016;Seneviratne et al, 2014;Tranberg et al, 2015).…”

“…while in the United States, American Indians/Alaskan Native women are less likely to receive guideline concordant care than White women(Javid et al, 2014). The persistence of these variations among diverse Indigenous populations spanning a range of geographical settings and health care systems indicates both the likely similarities of the underlying issues and challenges involved in addressing them.Some common themes that emerged from these studies include the need to promote awareness of and facilitate access to screening(Kolahdooz et al, 2014;Lawrenson et al, 2016;Tolma, Stoner, Li, Kim, & Engelman, 2014), improve general health of Indigenous women(Lawrenson et al, 2016;Sheppard, Chiarelli, Marrett, Nishri, & Trudeau, 2011) as well as prioritising further investigation into factors that impact treatment, so as to guide the design of culturally appropriate programmes and services that address their needs(Javid et al, 2014;Kolahdooz et al, 2014;Lawrenson et al, 2016;Tolma et al, 2014;Tranberg et al, 2015).…”

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

“…Indigenous Māori in New Zealand are known to have lower access, receive inferior quality cancer care and experience longer cancer treatment delays compared with non-Indigenous NZ Europeans for a variety of cancers [7–10]. For instance, Māori patients have been reported to experience longer delays for surgical treatment of breast and lung cancer, and to have a lower likelihood of receiving chemotherapy for bowel cancer compared with NZ European patients [7, 8].…”