Patients who are getting general CT exams could also be offered the opportunity for colorectal cancer (CRC) screening, thus improving colon screening rates, according to a study published in the May-June issue of Current Problems in Diagnostic Radiology.
Using CT as a tool to leverage colon screening could boost the health of subgroups of patients who may not be getting the preventive care they need, wrote a team led by Dr. Anand Narayan, PhD, of Massachusetts General Hospital in Boston.
"CT appointments may represent opportunities to improve overall colorectal cancer screening rates with CT colonography or other CRC screening methods among patients who have not received recommended screening," the group wrote. "Prior studies have suggested that offering patients a wide variety of CRC screening options improves adherence, particularly among racial and/or ethnic minority groups."
Second-leading cause of cancer death
Colorectal cancer is the second-leading cause of cancer-related death in the U.S., but screening uptake could use improvement, Narayan and colleagues noted. Previous studies have shown that particular patient subgroups -- like racial/ethnic minorities and those without insurance -- are less likely to be up to date on colorectal cancer screening, and therefore more likely to present with advanced disease. Barriers include fear or worry about getting screened and financial or logistical challenges.
But many patients undergo CT imaging each year, and CT colonography has shown high sensitivity for detecting polyps in the colon larger than 1 cm, according to the group. That's why viewing CT exams as an opportunity to screen for colorectal cancer could be good medicine.
"Patients who have experience undergoing CT scans may be more likely to adhere to colorectal cancer screening recommendations if they get screened with a modality (CT colonography) that they are already familiar with," the investigators wrote.
Narayan and colleagues sought to assess how many patients had undergone CT imaging but had not received recommended CRC screening, and to determine whether particular patient factors are associated with increased or decreased colon cancer screening rates.
The team used data from the 2015 National Health Interview Survey, including 16,206 survey respondents between the ages of 45 and 75 with no history of colorectal cancer screening (Curr Probl Diagn Radiol, May-June 2021, Vol. 50:3, pp. 332-336).
Of the total survey cohort, 50.8% underwent some form of colorectal cancer screening and 44.3% reported having received a CT scan. Among those who had a CT exam, 66.2% reported undergoing CRC screening of some kind; among those who did not receive colorectal cancer screening, 33.7% had undergone CT -- which translates to an estimated 15.3 million people across the U.S., the authors noted.
The team found that statistically significant factors associated with CRC screening included higher levels of household income and education were associated with higher odds of colorectal cancer screening adherence, while being Asian and not having insurance were associated with lower odds.
| Odds ratios for adherence to CRC screening among people who have undergone CT | ||
| Patient characteristic | Odds ratio | p-value |
| Education | ||
| Less than college | 1 | -- |
| College or more | 1.2 | 0.012 |
| Income | ||
| Household income | 1 | < 0.001 |
| Insurance status | ||
| Insured | 1 | -- |
| Uninsured | 0.51 | < 0.001 |
| Race/ethnicity | ||
| Black | 1.19 | 0.10 |
| White | 1 | -- |
| Hispanic | 0.88 | 0.32 |
| Other | 0.62 | 0.16 |
| Asian | 0.5 | 0.001 |
"Our study results demonstrate that among patients who have not received recommended CRC screening, nearly one out of three report having undergone a CT examination, representing an estimated 15 million people across the United States," the team wrote.
Take the opportunity
Imaging offers an opportunity to improve population health overall, according to Narayan and colleagues. It's been shown, for example, that women presenting for breast cancer screening can also be screened for intimate partner violence and lung cancer.
In similar fashion, CT exam intake questionnaires could be used to assess whether patients eligible for colorectal cancer screening have undergone it, and radiology practices could educate these patients on CRC screening options. They could also use strategies like phone calls to patients, point-of-care reminders to providers, guidance from patient navigators, and community outreach workers.
"Radiology practices may consider adopting interventions outside of radiology that have been used successfully to increase cancer screening rates," the authors concluded. "Prior studies have suggested that multifaceted, personalized approaches including a variety of outreach strategies are most likely to be successful. Radiology practices can work with other specialties to implement some of these interventions as part of coordinated strategies to improve screening adherence."
