Study findings published in Clinical and Translational Gastroenterology are the first to define specific geographic areas in the US where women diagnosed with colorectal cancer (CRC) before age 50 have higher mortality rates.1
The results emphasize the importance of defining patterns of variance in early-onset CRC survival in order to understand the impact of community health behaviors on early-onset CRC outcomes.
“Colorectal cancer is becoming more common in young adults, and we don’t entirely understand the ‘why’ just yet. This rising burden among young adults stresses the importance for accurate and early diagnosis of these malignancies,” lead author Andreana Holowatyj, PhD, MSCI, assistant professor of Medicine and Cancer Biology at Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, said in a press release.2 “Primary care physicians and gastroenterologists around the country, and particularly in Nashville and other hot spot regions, should keep colorectal tumors in the differential diagnosis of young patients presenting with signs/symptoms of colorectal cancer.”
Geographic hot spots were derived using data obtained from the Centers for Disease Control and Prevention national mortality data. In addition, researchers identified women ages 15 to 49 years diagnosed with CRC from 1999 to 2016 in the National Institutes of Health/National Cancer Institute’s Surveillance, Epidemiology, and End Results program.
Ultimately, approximately 1 in every 16 contiguous US counties were identified as hot spots (191 of 3,108). Moreover, 52.9% of hot spot counties (n = 101) were located in the South.
Of 28,790 women with early-onset CRC, 13.7% of cases (n = 3,954) resided in hot spot counties. Non-Hispanic Black individuals comprised on average 19.3% of the population in hot spot counties.
Notably, physical inactivity and fertility were community health behaviors that modestly correlated with hot spot residence among women with early-onset CRC (r = 0.21 and r = 20.23, respectively; P < .01). Specifically, nearly one quarter of adults living in hot spot counties reported no physical activity during their leisure time. Further, about 5% of women in these counties had a live birth in the past year.
Together, individual/community-level features accounted for distinct variance patterns in early-onset CRC survival among women (hot spot counties: 33.8%; non-hot spot counties: 34.1%).
“Together, these findings may inform cancer prevention/intervention strategies tailored to young patients and may ultimately help to inform knowledge to reverse early-onset CRC incidence trends and improve patient outcomes,” the authors wrote. “Additional studies to examine early-onset CRC incidence patterns by hot spot classification among women will be helpful to discern whether disease incidence rates are higher in regions with disproportionately high early-onset CRC mortality.”
The hot spot geography identified in this study differs from a similar study published earlier this year by Holowatyj et al. that revealed hot spot counties for early-onset CRC mortality among both men and women. In the prior study that looked at variation in overall early-onset CRC mortality, 92% of hot spot counties were also revealed to be in the South. However, for hot spots specifically among women, almost half of these counties were in the Midwest and Northeast.
“In our study published earlier this year, Nashville is not an area of high mortality for both men and women diagnosed with early-onset colorectal cancer, but when you take a step back and look at only women, now Davidson County and Nashville emerge,” explained Holowatyj. “These results emphasize the need to understand these pronounced disparities in early-onset colorectal cancer burden not only by geographic region, but also by sex and race/ethnicity.”
Other large-population counties with high mortality rates for women diagnosed with early-onset CRC included Miami-Dade County, Cook County (Chicago), Fulton County (Atlanta), New Castle County (Wilmington, Del.), Fairfield County (Bridgeport, Conn.), St. Louis County, Bergen County (New Jersey suburbs of New York metropolitan area), Queens County (Queens borough of New York), Mecklenburg County (Charlotte, N.C.), Hamilton County (Cincinnati, Ohio), Tulsa County, and Philadelphia County.