Cancer Incidence in Migrants in Australia: Patterns of Three Infection-Related Cancers

Abstract

Background: Australia provides an ideal population-base for cancer migration studies because of its multicultural society and high-quality cancer registrations. Among migrant groups there is considerable variability in the incidence of infection-related cancers; thus, the patterns of three such cancers were examined among migrant groups relative to Australian-born residents.

Methods: Using national incidence data for cancers of the stomach, liver, and cervix diagnosed during 2005 to 2014, incidence rates were compared for selected migrant groups with the Australian-born population using incidence rate ratios (IRR), from a negative binomial regression model.

Results: Wide variations in incidence between countries/regions of birth were observed for all three cancers (P < 0.0001). The patterns were similar for cancers of the stomach and liver, in that migrants from countries/regions with higher incidence rates maintained an increased risk in Australia, with the highest being among South American migrants (IRR = 2.35) for stomach cancer and among Vietnamese migrants (5.44) for liver cancer. In contrast, incidence rates of cervical cancer were lower for many migrant groups, with women from Southern Asia (0.39) and North Africa (0.42) having the lowest rates. The rate of cervical cancer was higher in migrants from New Zealand, Philippines, and Polynesia.

Conclusions: Several Australian migrant groups were found to experience a disproportionate burden of infection-related cancers; further studies of associated risk factors may inform the design of effective interventions to mediate these disparities.

Impact: By identifying these migrant groups, it is hoped that these results will motivate and inform prevention or early detection activities for these migrant groups. See related commentary Dee and Gomez, p. 1251.

Figure 1.

Adjusted incidence rate ratio^a and 95% CIs for stomach cancer relative to the Australian-born; (A) by country of birth^b (B) by region of birth.^{b a}Adjusted for age group at diagnosis, sex and year of diagnosis in a negative binomial regression model with Australian-born population as a reference. ^bCountries/Regions ordered by SACC code (see Table 2 for details).

Figure 2.

Adjusted incidence rate ratio^a and 95% CIs for liver cancer relative to the Australian-born; (A) by country of birth^b (B) by region of birth.^baAdjusted for age group at diagnosis, sex, and year of diagnosis in a negative binomial regression model with Australian-born population as a reference. ^bCountries/Regions ordered by SACC code (see Table 2 for details).

Figure 3.

Adjusted incidence rate ratio^a and 95% CIs for cervical cancer relative to the Australian-born; (A) by country of birth^b (B) by region of birth.^{b a}Adjusted for age group at diagnosis, and year of diagnosis in a negative binomial regression model with Australian-born population as a reference. ^bCountries/Regions ordered by SACC code (see Table 2 for details).