Incidence trends and spatial distributions of lung adenocarcinoma and squamous cell carcinoma in Taiwan

Lung cancer is the second most common cancer in Taiwan. After Taiwan implemented the Tobacco Hazards Prevention Act in 1997, smoking rates declined. However, the incidence rates of lung cancer for both sexes are still increasing, possibly due to risk factors other than smoking. We used age-period-cohort analysis to examine the secular trends of lung cancer incidence rates by histological type in Taiwan. A stabilized kriging method was employed to map these lung cancer incidence rates. Lung adenocarcinoma incidence rates increased, but lung squamous cell carcinoma incidence rates decreased, for both the sexes in recent birth cohorts, particularly in women. In Taiwan, the hotspots of lung adenocarcinoma incidence rates were in the northern, northeastern, and western coastal areas; the incidence rates increased rapidly in the western and southern coastal regions and southern mountainous regions. The high incidence rates of lung squamous cell carcinoma in men were in the southwestern and northeastern coastal areas. The incidence rates rapidly increased in the central and southern coastal and mountainous regions. For both sexes in Taiwan, lung squamous cell carcinoma incidence rates declined from 1997 to 2017, but lung adenocarcinoma increased. The increased incidence rates of lung adenocarcinoma may be related to indoor and outdoor air pollution. Some areas in Taiwan have increasing lung cancer incidence rates, including the northwestern and southern coasts and mountains, and warrant particular attention.

Automated summary

Lung cancer is the second most common cancer in Taiwan, with increasing incidence rates for both sexes. A study examined the time trends of lung cancer incidence rates by histological type using age-period-cohort analysis. Lung adenocarcinoma incidence rates increased, while lung squamous cell carcinoma incidence rates decreased, particularly in women. The distribution of hotspots for lung adenocarcinoma incidence rates was observed in certain areas of Taiwan, while high incidence rates of lung squamous cell carcinoma were found in specific regions.