Ethnic differences in breast cancer survival in New Zealand: contributions of differences in screening, treatment, tumor biology, demographics and comorbidities.

PURPOSE: We investigated the breast cancer survival disparity between Indigenous Maori and non-Indigenous European women in New Zealand, and quantified the relative contributions of patient, tumor and healthcare system factors toward this disparity. METHODS: All women diagnosed with breast cancer in Waikato, New Zealand, during 1999-2012 were identified from the Waikato Breast Cancer Register. Cancer-specific survivals were compared using Kaplan-Meier survival curves, while contributions of different factors toward the survival disparity were quantified with serial Cox proportional hazard modeling. RESULTS: Of the 2,679 women included in this study, 2,260 (84.4%) were NZ European and 419 (15.6%) were Maori. Compared with NZ European women, Maori women had a significantly higher age-adjusted cancer-specific mortality (HR 2.02, 95% CI 1.59-2.58) with significantly lower 5-year (86.8 vs. 76.1%, p < 0.001) and 10-year (79.9 vs. 66.9%, p < 0.001%) crude cancer-specific survivals. Stage at diagnosis made the greatest contribution (approximately 25-40%), while screening, treatment and patient factors (i.e., comorbidity, obesity and smoking) contributed by approximately 15% each toward the survival disparity. The final model accounted for almost all of the cancer survival disparity (HR 1.07, 95% CI 0.80-1.44). CONCLUSIONS: Maori women experience an age-adjusted risk of death from breast cancer, which is more than twice that for NZ European women. Equity-focussed improvements in health care, including increasing mammographic screening coverage and providing equitable quality and timely cancer care, may improve the survival disparity between Maori and NZ European women.

Cultural health literacy: the experiences of Maori in palliative care.

Health literacy is a concept that is frequently applied to the patient's ability to find and comprehend health information. However, recent literature has included the skill of the health professional and the accessibility of health resources as important factors in the level of health literacy achieved by individuals and populations. In 2014 a qualitative study undertaken in Aotearoa New Zealand, investigated the context of health literacy for Maori in a palliative care setting (Maori are the indigenous people of Aotearoa New Zealand). The study included the experiences of patients, whanau (families), and health professionals. METHOD: Individual semi-structured interviews were held with 21 patients, whanau and six key informants: a medical specialist, a service leader involved in developing culturally specific responses to patients, two Maori service managers, and two Maori health team leaders. Focus groups were held with a total of 54 health professionals providing palliative care services. DATA ANALYSIS: A thematic analysis was undertaken using a general inductive approach. The trustworthiness and reliability of the analysis was supported by sharing analysis of the transcripts among the research team. Member checking or respondent validation was used in seeking confirmation of the interim findings at five hui (meetings) with the research communities involved. FINDINGS: This study found that the shock and grief that attends a life-limiting illness made hearing and processing health information very difficult for patients and whanau. Further, 'hard conversations' about moving from active treatment to palliative care were often avoided by health professionals, leaving patients and whanau distressed and confused about their choices and prognosis. Finally, poor cultural health literacy on the part of organisations has likely impacted on late access to or avoidance of palliative care for Maori.

Accuracy and completeness of the New Zealand Cancer Registry for staging of invasive breast cancer.

PURPOSE: Population based cancer registries are an invaluable resource for monitoring incidence and mortality for many types of cancer. Research and healthcare decisions based on cancer registry data rely on the case completeness and accuracy of recorded data. This study was aimed at assessing completeness and accuracy of breast cancer staging data in the New Zealand Cancer Registry (NZCR) against a regional breast cancer register. METHODOLOGY: Data from 2562 women diagnosed with invasive primary breast cancer between 1999 and 2011 included in the Waikato Breast Cancer Register (WBCR) were used to audit data held on the same individuals by the NZCR. WBCR data were treated as the benchmark. RESULTS: Of 2562 cancers, 315(12.3%) were unstaged in the NZCR. For cancers with a known stage in the NZCR, staging accuracy was 94.4%. Lower staging accuracies of 74% and 84% were noted for metastatic and locally invasive (involving skin or chest wall) cancers, respectively, compared with localized (97%) and lymph node positive (94%) cancers. Older age (>80 years), not undergoing therapeutic surgery and higher comorbidity score were significantly (p<0.01) associated with unstaged cancer. The high proportion of unstaged cancer in the NZCR was noted to have led to an underestimation of the true incidence of metastatic breast cancer by 21%. Underestimation of metastatic cancer was greater for Maori (29.5%) than for NZ European (20.6%) women. Overall 5-year survival rate for unstaged cancer (NZCR) was 55.9%, which was worse than the 5-year survival rate for regional (77.3%), but better than metastatic (12.9%) disease. CONCLUSIONS: Unstaged cancer and accuracy of cancer staging in the NZCR are major sources of bias for the NZCR based research. Improving completeness and accuracy of staging data and increasing the rate of TNM cancer stage recording are identified as priorities for strengthening the usefulness of the NZCR.