International trends in primary liver cancer incidence from 1973 to 2007

Primary liver cancer (PLC) is a common cancer worldwide, especially in developing countries. Several previous studies using different datasets have summarized PLC incidence rates and trends in different populations. However, with changes in exposure to risk factors and the implementation of preventive measures, the epidemiology of PLC worldwide may have changed.

We extended the analyses using the latest data from Cancer Incidence in Five Continents over the 35-year period 1973-2007 from 24 populations in Americas, Asia, Europe and Oceania using Joinpoint regression analysis. We examined age-standardized rates (ASRs) of PLC by histologic subtypes for both males and females in 24 populations during the period 2003-2007.

We found that during the period 2003-2007, the highest ASRs for PLC were observed in some Asian populations, ranging from 19.0 to 26.7 per 100,000 in males and 4.8 to 8.7 per 100,000 in females. The international trends between 1973 and 2007 showed that ASRs for PLC were declining in several Asian populations. In contrast, ASRs for PLC were increasing in some European, American and Oceanian populations.

Although the reasons were not fully clear for these trends, public health measures in Asian populations and HCV transmission in European, American and Oceanian populations were likely to have contributed to these patterns. Meanwhile, other possible risk factors such as the consumption of alcohol, obesity, and nonalcoholic fatty liver disease should also be concerned for the burden of PLC.