A spatial study of oral & pharynx cancer mortality and incidence in the U.S.A.: 2000-2015

This is a national scale study of spatial oral and pharynx cancer mortality and incidence clusters in the contiguous U.S.A. Spatial and space-time analyses of incidence and mortality rates of oral and pharynx cancers in the contiguous U.S.A. were done at the county resolution, using mortality data for the years 2000-2014 and incidence data for 2001-2015. The disease surveillance software SaTScan™ is used to identify significant cancer clusters that are non-random. In addition to a cluster analysis, regression analysis was used to adjust cancer incidence and mortality for several covariates or risk factors. This is the first study of the contiguous U.S.A. for oral and pharynx cancer in which mortality and incidence rates are studied together. The geographic clustering for mortality is somewhat different from the clustering for incidence. There exist several significant clusters in the contiguous U.S.A., both for oral and pharynx cancer incidence and for mortality. Some of the significant clusters persisted even after adjusting for several key risk factors. These clusters areas suggest a need for further investigation to identify some local concerns or needs to further address such cancer types in those specific sites. We identified statistically significant spatial and space-time clusters of oral and pharynx cancer for mortality and also for incidence in the contiguous US at the county resolution. The most important risk factors for oral cancer incidence are diabetes, alcohol drinking, and obesity, while the top risk factors for mortality are race, cervical cancer, diabetes, and alcohol drinking.