Surveillance of the Incidence and Mortality of Oral and Pharyngeal, Esophageal, and Lung Cancer in Nevada: Potential Implications of the Nevada Indoor Clean Air Act.

Reviews of national and state-specific cancer registries have revealed differences in rates of oral, esophageal, and lung cancer incidence and mortality that have implications for public health research and policy. Many significant associations between these types of cancers and major risk factors, such as cigarette usage, may be influenced by public health policy such as smoking restrictions and bans-including the Nevada Clean Indoor Air Act (NCIAA) of 2006 (and subsequent modification in 2011). Although evaluation of general and regional advances in public policy have been previously evaluated, no recent studies have focused specifically on the changes to the epidemiology of oral and pharyngeal, esophageal, and lung cancer incidence and mortality in Nevada. Methods: Cancer incidence and mortality rate data were obtained from the National Cancer Institute (NCI) Division of Cancer Control and Population Sciences (DCCPS) Surveillance, Epidemiology and End Results (SEER) program. Most recently available rate changes in cancer incidence and mortality for Nevada included the years 2012-2016 and are age-adjusted to the year 2000 standard US population. This analysis revealed that the overall rates of incidence and mortality from these types of cancer in Nevada differs from that observed in the overall US population. For example, although the incidence rate of oral cancer is decreasing in the US overall (0.9%), it is stable in Nevada (0.0%). However, the incidence and mortality rates from esophageal cancer are also decreasing in the US (-1.1%, -1.2%, respectively), and are declining more rapidly in Nevada (-1.5%, -1.9%, respectively). Similarly, the incidence and mortality rates from lung are cancer are declining in the US (-2.5%, -2.4%, respectively) and are also declining more rapidly in Nevada (-3.2%, -3.1%, respectively). Analysis of previous epidemiologic data from Nevada (1999-2003) revealed the highest annual percent change (APC) in oral cancer incidence in the US was observed in Nevada (+4.6%), which corresponded with the highest APC in oral cancer mortality (+4.6%). Subsequent studies regarding reduced rates of cigarette use due to smoking restrictions and bans have suggested that follow up studies may reveal changes in the incidence and mortality rates of oral and other related cancers. This study analysis revealed that oral cancer incidence rates are no longer increasing in Nevada and that mortality rates have started to decline, although not as rapidly as the overall national rates. However, rapid decreases in both the incidence and mortality from esophageal and lung cancer were observed in Nevada, which strongly suggest the corresponding changes in oral cancer may be part of a larger epidemiologic shift resulting from improved public health policies that include indoor smoking restrictions and bans.