Regional variation in trajectories of colon cancer mortality, 2012-2021.
Authors: Sukhera Ahmed Bashir , Rodriguez Vazquez Jorge , Erazo Gloria , Fasola Ooreoluwa , Ullah Mosffa , Mathew Merry , Ogedegbe Oboseh John , Sanchez Asley , Garza John 
Published: January 2025

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Background:
Colorectal cancer (CRC) is the fourth most common cancer by incidence in the United States in 2024, and the second most common cause of cancer mortality in Texas. Rates of advanced CRC at diagnosis and cancer related mortality are higher in rural areas. Here we explore the variation in mortality trends across the eleven public health regions (PHR) of Texas from 2012 to 2021.
Methods:
We conducted a population-based cohort study of colon cancer mortality in Texas over the period 2012 through 2021. We queried the National Cancer Institute Surveillance, Epidemiology and End Results Program (SEER) for county level colon cancer deaths in Texas over the most recent available decade. Counties were aggregated into the eleven public health regions defined by the Texas Department of State Health Services. We calculated age-adjusted mortality rates (AAMRs) per 100,000 population using the direct standardization method based on the age group weights from the 2000 standard US population. Confidence intervals for AAMR were derived by estimating the standard error as the AAMR divided by square root of number of mortalities. The annual percent changes (APC) in AAMR were tested using negative binomial regression. Subgroup analyses included age group, sex, and race/ethnicity.
Results:
A total of 33,591 colon cancer mortalities were included in the study. Total colon cancer mortalities rose from 2,973 in 2012 to 3,800 in 2021. The statewide AAMR was initially 12.4 (95% CI 12.0 to 12.9), and did not change over the study period (APC -0.1% [95% CI -0.5% to 0.2%]; p = 0.5155) ending at (AAMR 12.5 [95% CI 12.1 to 12.9]). Divergent trajectories for AAMR across public health regions were observed. The largest decline in AAMR (APC -3.9% [95% CI -6.3 to -1.6]; p = 0.0013) occurred in region 10, where the AAMR fell from 14.2% [95% CI 8.6 to 19.7]) to AAMR 11.0 [95% CI 6.8 to 15.1]. Region 6 also saw a significant decrease (APC -1.1% [95% CI -1.8% to -0.4%]; p = 0.0029) falling from AAMR 12.2 [95% CI 11.3 to 13.2] to AAMR 11.2 [95% CI 10.4 to 11.9]. The largest significant increasing trend (APC +2.3% [95% CI 0.6% to 4.1%]; p = 0.0089) for AAMR was observed for region 9 rising from AAMR 12.4 (95% CI 9.6 to 15.3) to AAMR 15.4 (95% CI 12.3 to 18.4).
Conclusions:
Our analysis showed a significant and increasing trend in CRC related mortality in PHR 9. This region, colloquially termed West Texas, consists of 30 counties of which over 86% are designated as rural. Rural areas struggle with higher poverty, lower degree of higher education attainment, less access to healthcare and physicians, and a higher frequency of uninsured status. West Texas in particular also has a higher rate of smoking and obesity. However, PHR 10, which shares many similarities with PHR 9 such as rurality (83.3%) and similar socioeconomic and geographic challenges, witnessed the greatest decline in AAMR of the eleven PHR's in the same time frame, suggesting the presence of other factors which may be contributing to this increase.