The characteristics and outcomes of patients with colorectal cancer in New Zealand, analysed by Cancer Network.

AIM: The incidence of colorectal cancer (CRC) in New Zealand is high by international standards. Approximately 1,200 people in New Zealand die from this disease per year. Outcomes in New Zealand following a CRC diagnosis are poor. We aimed to describe the characteristics and outcomes of patients diagnosed with CRC across the four regional cancer networks in New Zealand. METHOD: Patient demographics, tumour characteristics and survival outcomes for all patients diagnosed with CRC between 2006 and 2015 were analysed retrospectively from the National Cancer Registry (NZCR) and National Mortality collection and were linked by National Health Index (NHI) number. RESULTS: A total of 29,221 CRC cases were recorded during the 10-year study period, of which the majority were cancer of the colon (67.9%). In this sample, 42.0% were >75 years, 52.1% were male and 88.1% were New Zealand European. After adjustment for factors such as age, gender, ethnicity year of diagnosis, cancer extent, cancer grade, lymph node and cancer site, cancer-related and all-cause survival were not significantly different by cancer network for those aged <75 but for patients aged >75 years, those living in the Central and Midland Cancer Network had a higher risk of dying of CRC compared to those in the Northern Cancer Network (1.12, 95% CI: 1.03-1.22 and 1.10, 95% CI: 1.02-1.18 respectively). Overall, Maori and Pacific people had worse cancer-specific and all-cause survival than New Zealand European. CONCLUSION: No regional variations were seen within New Zealand for the characteristics and survival outcomes of patients <75 diagnosed with CRC. The risk of dying from CRC increased for those >75, which is supportive of the international literature regarding outcomes for the elderly and CRC. We continue to show disparity in outcomes for Maori and Pacific patients diagnosed with CRC in New Zealand.