Differences in survival between Māori and New Zealand Europeans with prostate cancer.

Abstract

This study aims to examine the survival disparity between Māori men and New Zealand (NZ) Europeans diagnosed with prostate cancer. We identified men aged 40+ years in the Midland Cancer Network region registered with prostate cancer in 2007-2010 in the Cancer Registry. Data were extracted from patient notes of all Māori men and a sample of NZ Europeans. The survival disparity between Māori men and Europeans was estimated by the Kaplan-Meier method and Cox proportional-hazards regression models after adjusting for other factors. This study included 535 men with prostate cancer (135 Māori men and 400 Europeans). The 5-year cancer-specific survival was 98.6% for men diagnosed with localised cancer, 88.8% for locally advanced disease and 19.1% for metastatic cancer. The all-cause survival and the cancer-specific survival were both significantly poorer for Māori men than for NZ Europeans (log rank test: P = 0.004, 0.006 respectively). The hazard ratio of cancer-specific survival for Māori men was 2.01 (95% CI: 1.21-3.36) compared with NZ Europeans. Māori men with prostate cancer had poorer all-cause survival and cancer-specific survival than NZ Europeans. Māori men were at risk of having more advanced disease at diagnosis, which explains most of the survival inequity between Māori men and NZ Europeans.