Epidemiology of lung cancer in Oman: 20-year trends and tumor characteristics

Objectives: We sought to investigate the epidemiology of lung cancer and its trends in Oman over 20 years. Methods: We analyzed all cases of primary lung cancer reported to the Oman National Cancer Registry between 1996 and 2015. The World Standard Population was used to obtain age-standardized incidence rates (ASR) of lung cancer per 100 000. Analyses were conducted using univariate statistics. Results: A total of 956 cases of primary lung cancer cases were registered in Oman between 1996 and 2015, with a male to female ratio of 3:1. In men, the ASR was 8.2 per 100 000, while in females it was 2.6 per 100 000 over the entire study period. There were no statistically significant differences in the ASR among men or women when the data was divided over three calendar periods (1996-2005, 2006-2015, and 1996-2015) (p = 0.332 and p = 0.577, respectively). There was also no increasing trend in the incidence of lung cancer. The risk of lung cancer onset commenced in the 30-34 year age group and the mean age at diagnosis was 60.0 years for men and 61.0 years for women. Adenocarcinoma was the most common type of lung cancer among Omanis with a higher proportion in females compared to males. Conclusions: Oman has one of the lowest incidence rates of lung cancer in the world with no evidence of an increasing trend of this cancer type. This could be attributed to low uptake of tobacco smoking among both sexes. National authorities should capitalize on this finding to avoid any future lung cancer epidemics especially those driven by tobacco use.