Lung Cancer Type Varies by Location in Kentucky

May 07, 2019


A new study from the University of Kentucky College of Public HealthUK College of Medicine, UK HealthCare Markey Cancer Center, and Kentucky Cancer Registry investigates the spatial and temporal distribution of lung cancer histological types in Kentucky, a largely rural state with high rates of smoking and obesity, to discern population-level trends that might reflect variation in these and other risk factors. Results of the investigation appear in a new paper published in Cancer Control. The first author is Dr. W. Jay Christian, assistant professor of Epidemiology. Co-authors are Dr. Nathan Vanderford, UK College of Medicine; Dr. Jaclyn McDowell, Kentucky Cancer Registry; Dr. Bin Huang, associate professor of Biostatistics; Dr. Eric B. Durbin, UK College of Medicine; Dr. Kimberly Absher, UK College of Medicine; Courtney J. Walker, department of Epidemiology; and Dr. Susanne M. Arnold, UK College of Medicine. 

Using data from the Kentucky Cancer from 1995 through 2014, investigators adjusted for age, gender, and race, to characterize risk for specific histological types—small cell, adenocarcinoma, squamous cell, and other types—throughout Kentucky, and compared to maps of risk factors.


Toward the end of the study period, adenocarcinoma was more common among all population subgroups in north-central Kentucky, where smoking and obesity are less prevalent. During the same time frame, squamous cell, small cell, and other types were more common in rural Appalachia, where smoking and obesity are more prevalent, and in some high poverty urban areas.


Spatial and temporal patterns in the distribution of histological types of lung cancer are likely related to regional variation in multiple risk factors. High smoking and obesity rates in the Appalachian region, and likely in high poverty urban areas, appeared to coincide with high rates of squamous cell and small cell lung cancer. In north-central Kentucky, environmental exposures might have resulted in higher risk for adenocarcinoma specifically.


This study demonstrates that significant and substantial spatial variation exists in the histological types of lung cancer diagnosed in Kentucky, a state with an especially high burden of lung cancer. Along with significantly higher risk for most types of lung cancer in high poverty areas, likely related to higher smoking rates, we observed recent increases in risk for adenocarcinoma in a region that has lower smoking and obesity rates than the rest of the state and is additionally more urban and affluent. Future research should examine data from additional cancer registries in other states and explore potential risks associated with air pollution and other environmental exposures in metropolitan areas to better understand spatial and temporal trends in lung cancer histology.



The University of Kentucky College of Public Health is a catalyst of positive change for population health, with a mission to develop health champions, conduct multidisciplinary and applied research, and collaborate with partners to improve health in Kentucky and beyond.