Women diagnosed with early-onset colorectal cancer have a greater risk of dying from the disease depending upon their county of residence, according to a study published in Clinical and Translational Gastroenterology.
The study is the first to define specific geographic areas in the United States where women diagnosed with colorectal cancer before age 50 have higher mortality rates. The researchers obtained data from the U.S. Centers for Disease Control and Prevention and then analyzed data on 28,790 women collected from 1999 to 2016 by the Surveillance, Epidemiology, and End Results program from the National Cancer Institute to understand patterns of community health behaviors that may be linked to these survival disparities. Davidson County, where Nashville is located, is among the hot spot counties.
"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. 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," said Andreana Holowatyj, Ph.D., MSCI, assistant professor of Medicine and Cancer Biology at Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, who is the study's lead author.
Early-stage diagnosis increases survival odds as the cancer may be easier to treat, but many people with early-onset colorectal cancer may be delayed in diagnosis as colonoscopies -- a routine method of detection for colorectal polyps and tumors -- are not recommended for individuals at average risk of colorectal cancer until age 45.
Approximately one in every 16 counties were identified as hot spots across the contiguous United States. Physical inactivity and fertility may be factors contributing to this geographic variation in survival among young women with colorectal cancer since those community health behaviors modestly correlated with hot spot residence, but the researchers noted that more study is needed to identify health behaviors that can be modified within these populations to improve patient survival. Nearly one quarter of adults living in hot spot counties reported no physical activity during their leisure time. About 5% of women in these counties had a live birth in the past year. Non-Hispanic Black individuals comprised on average 19.3% of the population in hot spot counties.
The hot spot geography identified in this study of women with early-onset colorectal cancer mortality differs from a similar study published earlier this year by Holowatyj and colleagues that revealed hot spot counties for early-onset colorectal cancer mortality among both men and women. In the prior study that looked at variation in overall early-onset colorectal cancer mortality, 92% of hot spot counties were in the South. However, for hot spots specifically among women, nearly 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," Holowatyj said. "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."