Lung Cancer and Risk Factors in Lebanon: Epidemiology, Temporal Trends, and Comparison to Countries From Different Regions in the World

BACKGROUND: Lung cancer (Lca) is the leading cause of cancer morbidity and mortality worldwide. This study examines the Lca incidence and trends in Lebanon and compares them to regional and global ones. It also discusses Lca risk factors in Lebanon. METHODS: Lung cancer data from the Lebanese National Cancer Registry for 2005 to 2016 was obtained. The age-standardized incidence rates (ASRw) and age-specific rates per 100 000 population were calculated. RESULTS: Lung cancer ranked second for cancer incidence in Lebanon from 2005-2016. Lung cancer ASRw ranged from 25.3 to 37.1 per 100 000 males and 9.8 to 16.7 per 100 000 females. Males 70-74 and females 75+ had the highest incidence. Lung cancer ASRw in males increased significantly at 3.94% per year from 2005 to 2014 (P > .05), then decreased non-significantly from 2014 to 2016 (P < .05). Lung cancer ASRw in females increased significantly at 11.98% per year from 2005 to 2009 (P > .05), then increased non-significantly from 2009 to 2016 (P < .05). Males' Lca ASRw in Lebanon was lower than the global average in 2008 and became similar in 2012 (34.1 vs 34.2 per 100 000); However, females' Lca ASRw was almost comparable to the global average in 2008 and exceeded it in 2012 (16.5 vs 13.6, respectively, per 100 000). Males’ and Females’ Lca ASRw in Lebanon were among the highest in the Middle East and North Africa (MENA) region but lower than those estimated for North America, China and Japan, and several European countries. The proportion of Lca cases attributed to smoking among Lebanese males and females was estimated at 75.7% and 66.3% for all age groups, respectively. The proportion of Lca cases attributed to air pollution with PM(10) and PM(2.5) in Lebanon was estimated at 13.5% for all age groups. CONCLUSION: Lung cancer incidence in Lebanon is among the highest in the MENA region. The leading known modifiable risk factors are tobacco smoking and air pollution.