Objective: To investigate time trends in hepatocellular carcinoma (HCC) incidence disparities, and ethnic differences in risk factors, comorbidity and treatment pathways among HCC patients.
Methods: Cohorts of the NZ population (1981-2004) were created and probabilistically linked to cancer registry records to investigate trends in incidence by ethnicity over time. Hospital notes of 97 Māori and 92 non-Māori HCC patients diagnosed between 01/01/2006 and 31/12/2008 in NZ's North Island were reviewed.
Results: Liver cancer incidence was higher among Māori for all time periods. Compared with non-Māori, Māori males had nearly five times the rate of liver cancer (pooled RR=4.79, 95% CI 4.14-5.54), and Māori females three times the rate (pooled RR= 3.02, 95% CI 2.33-3.92). There were no significant differences in tumour characteristics or treatment of Māori and non-Māori patients with HCC. Māori more commonly had hypertension (51% versus 25%) while more non-Māori had cirrhosis recorded (62% versus 41%). The prevalence of hepatitis B among Māori patients (56%; 95% CI 45%-67%) was more than double that of non-Māori (27%; 95% CI 19%-36%). The hazard ratio for cancer-specific death for Māori compared with non-Māori was 1.36 (95% CI 0.96-1.92).
Conclusions and implications: HCC remains an important health problem particularly for Māori men. Efforts to improve coverage of screening for hepatitis B and surveillance of those with chronic hepatitis should be a priority to address the large inequalities found in liver cancer epidemiology.