Has lung cancer incidence rate reached its peak in China? Secular changes in lung cancer incidence rates based on an urban Chinese population

Purpose The objective of this study was to describe trends in the incidence rates from primary lung cancer in a geographically defined Chinese population. Methods Primary lung cancer cases (N = 39,731) diagnosed between 1981 and 2000 were identified by the Tianjin Cancer Registry. Age-adjusted to the world standard population and age- specific incidence rates were examined in both males and females. Changes in incidence rates over time were also examined by birth cohort. Poisson regression was used to assess the incidence trends. Results Crude and age-adjusted incidence rates in the study period were: 66.2/100,000 and 45.2/100,000 in males; and 47.7/100,000 and 28.2/100,000 in females, respectively. Birth cohort was a significant factor affecting the incidence rates of lung cancer. For those born before the year 1930, lung cancer incidence rates increased as the birth years advanced; whereas for those born after 1930, age specific incidence rates decreased as the birth years advanced. Results from the Poisson regression analyses suggested a statistically significantly increasing trend of incidence rates of lung cancer between 1981 and 2000. However, much of the increase in age-adjusted incidence rates occurred between 1981 and 1990. Unlike many previous findings and projections, the findings from this research suggest the age-adjusted incidence rate has stabilized in recent years. Conclusion Through most of the study period, lung cancer incidence rates increased in both males and females. While the study results suggest that the age-adjusted incidence rates may have reached their peaks, as the Chinese population ages and smoking prevalence remains high, the overall burden of lung cancer is expected to grow.