SAN FRANCISCO – Young adults with colorectal cancer who live in neighborhoods with higher levels of disadvantage differ on health measures, present with more advanced disease, and have poorer survival. These were among key findings of a retrospective cohort study reported at the 2020 GI Cancers Symposium.
The incidence of colorectal cancer has risen sharply – 51% – since 1994 among individuals aged younger than age 50 years, with the greatest uptick seen among those aged 20-29 years (J Natl Cancer Inst. 2017;109. doi: 10.1093/jnci/djw322).
“Sociodemographic disparities have been linked to inferior survival. However, their impact and association with outcome in young adults is not well described,” said lead investigator Ashley Matusz-Fisher, MD, of the Levine Cancer Institute in Charlotte, N.C.
The investigators analyzed data from the National Cancer Database for the years 2004-2016, identifying 26,768 patients who received a colorectal cancer diagnosis when aged 18-40 years.
Results showed that those living in areas with low income (less than $38,000 annually) and low educational attainment (high school graduation rate less than 79%), and those living in urban or rural areas (versus metropolitan areas) had 24% and 10% higher risks of death, respectively.
Patients in the low-income, low-education group were more than six times as likely to be black and to lack private health insurance, had greater comorbidity, had larger tumors and more nodal involvement at diagnosis, and were less likely to undergo surgery.
Several factors may be at play for the low-income, low-education group, Dr. Matusz-Fisher speculated: limited access to care, lack of awareness of important symptoms, and inability to afford treatment when it is needed. “That could very well be contributing to them presenting at later stages and then maybe not getting the treatment that other people who have insurance would be getting.
“To try to eliminate these disparities, the first step is recognition, which is what we are doing – recognizing there are disparities – and then making people aware of these disparities,” she commented. “More efforts are needed to increase access and remove barriers to care, with the hope of eliminating disparities and achieving health equity.”
Several studies have looked at mitigating sociodemographic-related disparities in colorectal cancer outcomes, according to session cochair John M. Carethers, MD, AGAF, professor and chair of the department of internal medicine at the University of Michigan, Ann Arbor.
A large Delaware initiative tackled the problem via screening (J Clin Oncol. 2013;31:1928-30). “Now this was over 50 – we don’t typically screen under 50 – but over 50, you can essentially eliminate this disparity with navigation services and screening. How do you do that under 50? I’m not quite sure,” he said in an interview, adding that some organizations are recommending lowering the screening age to 45 or even 40 years in light of rising incidence among young adults.
However, accumulating evidence suggests that there may be inherent biological differences that are harder to overcome. “There is a lot of data … showing that polyps happen earlier and they are bigger in certain racial groups, particularly African Americans and American Indians,” Dr. Carethers elaborated. What is driving the biology is unknown, but the microbiome has come under scrutiny.
“So you are a victim of your circumstances,” he summarized. “You are living in a low-income area, you are eating more proinflammatory-type foods, you are getting your polyps earlier, and then you are getting your cancers earlier.”