Small Numbers, Big Challenges: Adolescent and Young Adult Cancer Incidence and Survival in New Zealand

Abstract

Purpose: This study was undertaken to determine cancer survival and describe the unique spectrum of cancers diagnosed among New Zealand's adolescents and young adult (AYA) population.

Methods: Registrations for 1606 15-24 year olds diagnosed with a new primary malignant tumor between 2000 and 2009 were obtained from the New Zealand Cancer Registry and classified according to AYA diagnostic group and subgroup, age, sex, and prioritized ethnicity. Age-standardized incidence rates (IRs) per million person years and 5-year relative survival ratios were calculated.

Results: Cancer incidence was 228.6 per million for adolescents aged 15-19 years and 325.7 per million for young adults aged 20-24 years. Overall IRs were consistent across all ethnic groups but there were unique ethnic differences by tumor group including a higher incidence of bone tumors, carcinoma of the gastrointestinal tract, and gonadal germ cell tumors among Maori, a higher incidence of leukemia among Pacific peoples, and a higher incidence of melanoma among non-Maori/non-Pacific peoples. Five-year relative survival for adolescents (75.1%) and AYA overall (80.6%) appeared poorer than had been achieved in other high-income countries. Maori (69.5%) and Pacific (71.3%) AYA had lower 5-year survival compared to non-Maori/non-Pacific peoples (84.2%).

Conclusion: The survival disparities observed require further investigation to identify and address the causes of these inferior outcomes. The newly established AYA Cancer Network Aotearoa has been tasked with improving cancer survival and care and ensuring equality of access for New Zealand AYAs with cancer.

Keywords: disparities; ethnicity; incidence; survival.