Routine Colorectal Cancer Screening Research Articles

Perspectives on clinical adoption barriers to blood-based multi-cancer early detection tests across stakeholders.

e13574 Background: Current United States Preventive Services Task Force (USPSTF) recommendations include routine screening for breast, cervical, colorectal, and lung cancer; however, two out of every three cancer cases occur in other indications leading to diagnosis in advanced stages of the disease and higher likelihood of mortality. Current recommended cancer screening and early detection tests also face several hurdles hindering equitable access in a real-world setting. Blood-based MCED tests can impact cancer screening and early detection by monitoring for multiple different cancer types at once via a blood draw that can detect cancers in multiple indications, including indications where screening is not performed routinely today. Given their nascency, the role of blood-based MCED tests in clinical practice is currently undefined. To help facilitate the appropriate integration of MCED tests into patient care, it is important to understand the perspectives of stakeholders on the anticipated challenges to implementation. Methods: We conducted three separate double-blinded surveys in July 2023 of representative cohorts of U.S. Healthcare providers (HCPs) (n=238) that are or act as primary care providers (general practitioners and obstetrics and gynecologists (OB-GYNs)), payers (n=40), and patients (n=116), to evaluate the current cancer screening and early detection landscape and gather perspectives on barriers to implementation of new cancer screening technologies, including blood-based MCED tests. Results: Of the surveyed HCPs and payers, >90% and 100% respectively reported to be aware of MCED tests. However, <10% of HCPs reported having ordered an MCED test and 80% of payers had not yet evaluated an MCED test for coverage under their plan at the time of the survey. The survey results indicated that there is broad agreement on the value proposition that blood-based MCED tests would improve patient outcomes with earlier intervention. Despite this recognition, the survey highlighted that there is limited use today due to the perceived lack of clinical accuracy and utility data, high out-of-pocket patient costs, and lack of payer coverage. Conclusions: To overcome the hurdles for future widespread adoption of blood-based MCED tests, increased investment in data generation, education, and implementation of logistical support for HCPs will be critical. Initiatives include collaborations between stakeholders to generate near-term clinical utility data, equipping HCPs with the ability to educate patients on test accuracy, and seamlessly integrating the testing process into the patient visit workflow. The findings of this study can help build understanding of the anticipated barriers and inform strategies to alleviate them and build a foundation for clinical adoption of blood-based MCED tests.

Perspectives on Clinical Adoption Barriers to Blood-Based Multi-Cancer Early Detection Tests across Stakeholders.

Current United States Preventive Services Task Force (USPSTF) recommendations include routine screening for breast, cervical, colorectal, and lung cancer; however, two out of every three cancer cases occur in other indications, leading to diagnoses in advanced stages of the disease and a higher likelihood of mortality. Blood-based multi-cancer early detection (MCED) tests can impact cancer screening and early detection by monitoring for multiple different cancer types at once, including indications where screening is not performed routinely today. We conducted a survey amongst healthcare providers (HCPs), payers, and patients within the U.S. health system to understand the current utilization of cancer screening tests and the anticipated barriers to widespread adoption of blood-based MCED tests. The results indicated that the community favors the adoption of blood-based MCED tests and that there is broad agreement on the value proposition. Despite this recognition, the survey highlighted that there is limited use today due to the perceived lack of clinical accuracy and utility data, high out-of-pocket patient costs, and lack of payer coverage. To overcome the hurdles for future widespread adoption of blood-based MCED tests, increased investment in data generation, education, and implementation of logistical support for HCPs will be critical.

Abstract 7294: CREATE-2: Colorectal cancer & adenoma test evaluation of a multi-omic blood test

Abstract Background: Colorectal cancer (CRC) is the third most common cancer worldwide, with almost 2 million new cases reported in 2020. CRC develops over time from a pre-cancerous stage (adenoma) - the ‘adenoma-carcinoma sequence’. Pre-cancerous lesions, such as Higher Risk Adenomas (HRA), harbour an increased risk of developing into CRC and their features are defined according to size, number and histological features. Screening for signs of CRC is recommended for average-risk adults using faecal immunochemical testing (FIT) in the UK, to enable the removal of pre-cancerous lesions and treatment of early-stage cancers. However, the performance of FIT is limited. Approximately 10% of CRC diagnoses have a negative FIT result, and it currently has ~93% false positive rate. Moreover, the sensitivity for detecting AA is only 24%, highlighting the need for alternative strategies. Methods: A promising strategy for earlier CRC detection is the clinical use of Fourier transform infrared (FTIR) spectroscopy. The Dxcover® Colorectal Cancer Liquid Biopsy is a rapid multi-omic test that interrogates a blood sample with infrared (IR) radiation and produces a distinctive signature that represents the whole biomolecular profile of the sample. Rather than focusing on individual biomarkers, the technique encompasses the full range of diagnostic information from both the tumor and the non-tumor response. In the initial CREATE (ColoREctal Cancer & Adenoma Test Evaluation) feasibility study, the potential of the technology was highlighted in a retrospective cohort of patients comprising 100 CRC, 92 adenoma samples and 104 colonoscopy screening controls diagnosed as non-cancer. At 90% specificity, the test reported 80% CRC sensitivity and 59% HRA sensitivity. CREATE-2 is a prospective, observational, multicenter study, currently recruiting patients across the United States. The primary objective of the study is to determine the diagnostic accuracy of the blood-based Dxcover Colorectal Cancer Liquid Biopsy for CRC and HRA, and collectively as advanced colorectal neoplasia. Primary outcomes are sensitivity, specificity, negative predictive value, and positive predictive value of the test as compared to the standard of care screening modality. The study population is comprised of patients aged 45-84 considered ‘average-risk’ for CRC, undergoing routine CRC screening as standard of care. Patients are treatment naïve for CRC/HRA and must be willing to consent to blood draw pre-bowel preparation, and follow-up for 24 months. A rapid blood test that is sensitive to pre-cancerous lesions and early-stage CRC could substantially improve patient outcomes. Current screening programs have addressable shortcomings, and the emergence of new technologies is essential to support earlier CRC detection. Citation Format: James M. Cameron, Georgios Antoniou, Rose McHardy, David Palmer, Alexandra Sala, Matthew Baker. CREATE-2: Colorectal cancer & adenoma test evaluation of a multi-omic blood test [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7294.

Routine Fecal Occult Blood Screening and Colorectal Cancer Mortality in Sweden

Population-based colorectal cancer (CRC) screening programs are implemented worldwide, but there are difficulties evaluating their effectiveness. The magnitude of routine CRC screening effectiveness regarding cancer-specific mortality is unclear. To evaluate cancer-specific mortality associated with early vs late or no invitation for routine CRC screening using fecal occult blood testing. This prospective cohort study was performed in the region of Stockholm-Gotland, Sweden, between January 1, 2008, and December 31, 2021. All individuals of the target population of screening born from 1938 to 1954 were included. Data were analyzed from December 12, 2022, to June 25, 2023. Individuals were invited early (2008-2012), late (2013-2015), or not at all to screening with biennial guaiac-based fecal occult blood test. The early invitation group was considered the exposure group and the late or no invitation group was considered the control group. The main outcome was cancer-specific mortality, defined as CRC registered in the Cancer Register with CRC as underlying cause of death in the Cause of Death Register. Excess mortality was calculated as all-cause deaths among the individuals with CRC subtracted from the expected number of deaths had they not had CRC. Poisson regression analysis based on deaths and person-years was used to estimated mortality rate ratio (RR) with 95% CIs, adjusted for follow-up years and attained age. In total, 379 448 individuals (193 436 [51.0%] female) were invited for CRC screening, including 203 670 individuals in the exposure group and 175 778 in the control group. The mean screening participation rate was 63.3%, and there was a maximum of 14 years follow-up. There were 834 CRC deaths in 2 190 589 person-years in the exposure group, compared with 889 CRC deaths in 2 249 939 person-years in the control group. Individuals who underwent early CRC screening had reduced adjusted risk of CRC mortality (RR, 0.86; 95% CI, 0.78-0.95) and excess mortality (RR, 0.84; 95% CI, 0.75-0.93). This prospective cohort study of routine screening with fecal occult blood testing found a 14% decrease in CRC mortality associated with screening. The true association of screening with reduced mortality is expected to be higher due to some coexistence of testing in the control group and CRC deaths diagnosed more than 2 years after screening.

Abstract A044: Creating culturally relevant colorectal cancer screening messages and materials for tribal communities in the Great Plains

Abstract Introductory sentences indicating the purposes of the study: We applied a modified version of boot camp translation (BCT), a validated community participatory approach, to engage tribal community members in the Great Plains to develop culturally and locally relevant colorectal cancer (CRC) screening messages and materials. Brief description of pertinent experimental procedures: CRC is one of the leading causes of cancer death in the United States and disproportionally affects American Indian adults, especially American Indians living in the Great Plains. Routine CRC screening leads to earlier diagnosis and prolonged survival from the disease. However, American Indian adults are less likely to be up to date on CRC screening than White adults, highlighting the need to increase CRC screening within this community. In partnership with the Great Plains Tribal Leaders Health Board and the National Association of Chronic Disease Directors, we used a modified BCT approach to elicit feedback from tribal community members to create messages and materials that motivate tribal members to get screened for CRC. To make the BCT process more meaningful for our partner communities, we reframed the BCT sessions by referring to them as listening sessions. Eligible tribal community members recruited were between the ages of 45-75 and agreed to participate in all three listening sessions over a two-month period. The sessions consist of one five-hour in-person gathering in Rapid City, South Dakota, and two one-hour follow-up video-conferencing calls. The in-person session included a cultural presentation of Lakota teachings by a local hoop dancer, CRC education by an expert in CRC research, a presentation by local leaders on interventions to increase community access to CRC screening, and discussions on CRC knowledge, beliefs, barriers to screening, and messages/materials to help increase screening. The follow-up sessions, scheduled to occur in the summer of 2023, will gather feedback on draft materials and messages. Summary of the new unpublished data: A total of 38 adults participated in the first listening session. The key themes emphasized the importance of: 1) including Lakota words in the messages/materials as language is tied to cultural identity, 2) creating messaging/materials that are relatable, address local barriers, and include resources and cultural imagery, 3) applying a multigenerational approach to screening education in the messages and materials, 4) including cultural details about healing traditions, and 5) using visuals for colon health education and screening education. The participants suggested using videos in clinics, radio ads, visual stories, brochures, and text messages as the primary channels to disseminate the messages/materials. Statement of conclusions: We successfully used a modified BCT approach to incorporate participant feedback to develop CRC screening messages and materials and identified preferred dissemination channels for the Great Plains tribal communities. Final materials will be showcased. Citation Format: Priyanka Gautom, Jamie H. Thompson, Jennifer S. Rivelli, Senait R. Tadesse, Richard Mousseau, LaToya Brave Heart, Kelley LeBeaux, Derrick Molash, Lorrie Graaf, Dawn Wiatrek, Gloria D. Coronado. Creating culturally relevant colorectal cancer screening messages and materials for tribal communities in the Great Plains [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr A044.

Black-White disparities in colorectal cancer outcomes: a simulation study of screening benefit.

The US Black population has higher colorectal cancer (CRC) incidence rates and worse CRC survival than the US White population, as well as historically lower rates of CRC screening. The Surveillance, Epidemiology, and End Results incidence rate data in people diagnosed between the ages of 20 and 45 years, before routine CRC screening is recommended, were analyzed to estimate temporal changes in CRC risk in Black and White populations. There was a rapid rise in rectal and distal colon cancer incidence in the White population but not the Black population, and little change in proximal colon cancer incidence for both groups. In 2014-2018, CRC incidence per 100 000 was 17.5 (95% confidence interval [CI] = 15.3 to 19.9) among Black individuals aged 40-44 years and 16.6 (95% CI = 15.6 to 17.6) among White individuals aged 40-44 years; 42.3% of CRCs diagnosed in Black patients were proximal colon cancer, and 41.1% of CRCs diagnosed in White patients were rectal cancer. Analyses used a race-specific microsimulation model to project screening benefits, based on life-years gained and lifetime reduction in CRC incidence, assuming these Black-White differences in CRC risk and location. The projected benefits of screening (via either colonoscopy or fecal immunochemical testing) were greater in the Black population, suggesting that observed Black-White differences in CRC incidence are not driven by differences in risk. Projected screening benefits were sensitive to survival assumptions made for Black populations. Building racial disparities in survival into the model reduced projected screening benefits, which can bias policy decisions.

Patient Willingness to Use a Pharmacy-Based Colorectal Cancer Screening Service: A National Survey of U.S. Adults.

We aimed to understand U.S. adults' willingness to use a pharmacy-based fecal immunochemical test (FIT) distribution service for routine colorectal cancer screening called PharmFIT using Diffusion of Innovation Theory, evaluating patient's appraisals of the program's relative advantage, compatibility, and complexity. From March to April 2021, we conducted a national online survey of 1,045 U.S. adults ages 45 to 75. We identified correlates of patient willingness to use PharmFIT using structural equation modeling. Most respondents (72%) were willing to get a FIT from their pharmacy for their regular colorectal cancer screening. Respondents were more willing to participate in PharmFIT if they perceived higher relative advantage ($\hat{\beta}$= 0.184; confidence interval, CI95%: 0.055-0.325) and perceived higher compatibility ($\hat{\beta}$ = 0.422; CI95%: 0.253-0.599) to get screened in a pharmacy, had longer travel times to their primary health care provider ($\hat{\beta}$ = 0.007; CI95%: 0.004-0.010). Respondents were less willing to participate in PharmFIT if they were 65 years or older ($\hat{\beta}$ = -0.220; CI95%: -0.362 to -0.070). Most U.S. adults would be willing to participate in PharmFIT for their routine colorectal cancer screening. Patient perceptions of the relative advantage and compatibility of PharmFIT were strongly associated with their willingness to use PharmFIT. Pharmacies should account for patient preferences for these two traits of PharmFIT to increase adoption and use. Pharmacy-based colorectal cancer screening may be a viable public health strategy to significantly increase equitable access to screening for U.S. residents.

The Role of Health Information Technology on Colorectal Cancer Screening Participation Among Smokers In The United States.

Background: Despite advances in its prevention and early detection, colorectal cancer (CRC) remains a leading cause of morbidity and mortality in the United States and smokers are at an increased risk. Health information technology (HIT) has shown promise in the uptake of preventive health services, including CRC, and may prove useful among smokers. Methods: We obtained data from 7,419 adults who completed the 2018-2020 Health Information National Trends Survey. Using multivariable logistic regression models, we examined the relationship between HIT use and CRC screening participation. Results: Over 20% of current smokers had no access to HIT tools, and those with access were less likely than never smokers to use HIT in checking test results (odds ratio [OR] 0.58; 95% confidence interval [CI] [0.42-0.80]). Among former smokers, using HIT to check test results (OR 3.41; 95% CI [1.86-6.25]), look up health information online (OR 2.20; 95% CI [1.15-4.22]), and make health appointments (OR 2.86; 95% CI [1.39-5.89]) was associated with increased participation in CRC screening. Among current smokers, the use of HIT was not associated with a change in CRC screening participation. Conclusion: HIT use is associated with higher levels of CRC screening among former smokers, which is reassuring given their increased risk of CRC. The low ownership and use of HIT among current smokers of CRC screening age presents a challenge that may limit the integration of HIT into routine CRC screening services.

Multi-level Factors Influencing Decisions About Stopping Surveillance Colonoscopy in Older Adults: a Qualitative Study.

Little is known about patient or provider experience and perceptions of stopping surveillance among older adults with a history of colon polyps. While guidelines recommend ceasing routine colorectal cancer screening in adults > 75years and those with limited life expectancy, guidance for ceasing surveillance colonoscopy in those with prior colon polyps suggests individualizing recommendations. Identify processes, experiences, and gaps around individualizing decisions to stop or continue surveillance colonoscopy for older adults and areas for improvement. Phenomenological qualitative study design using recorded semi-structured interviews from May 2020 through March 2021. 15 patients aged ≥ 65 in polyp surveillance, 12 primary care providers (PCPs), and 13 gastroenterologists (GIs). Data were analyzed using a mixed deductive (directed content analysis) and inductive (grounded theory) approach to identify themes related to stopping or continuing surveillance colonoscopies. Analysis resulted in 24 themes and were clustered into three main categories: health and clinical considerations; communication and roles; and system-level processes or structures. Overall, the study found support for discussions around age 75-80 on stopping surveillance colonoscopy with considerations for health and life expectancy and that PCPs should take a primary role. However, systems and processes for scheduling surveillance colonoscopies largely bypass PCPs which reduces opportunities to both individualize recommendations and facilitate patients' decision-making. This study identified gaps in processes to implement current guidelines for individualizing surveillance colonoscopy as adults grow older, including opportunities to discuss stopping. Increasing the role of PCPs in polyp surveillance as patients grow older provides more opportunities for individualized recommendations, so patients can consider their own preferences, ask questions, and make a more informed choice for themselves. Changing existing systems and processes and creating supportive tools for shared decision-making specific to older adults with polyps would improve how surveillance colonoscopy is individualized in this population.

AI-based CT Body Composition Identifies Myosteatosis as Key Mortality Predictor in Asymptomatic Adults.

Background Body composition data have been limited to adults with disease or older age. The prognostic impact in otherwise asymptomatic adults is unclear. Purpose To use artificial intelligence-based body composition metrics from routine abdominal CT scans in asymptomatic adults to clarify the association between obesity, liver steatosis, myopenia, and myosteatosis and the risk of mortality. Materials and Methods In this retrospective single-center study, consecutive adult outpatients undergoing routine colorectal cancer screening from April 2004 to December 2016 were included. Using a U-Net algorithm, the following body composition metrics were extracted from low-dose, noncontrast, supine multidetector abdominal CT scans: total muscle area, muscle density, subcutaneous and visceral fat area, and volumetric liver density. Abnormal body composition was defined by the presence of liver steatosis, obesity, muscle fatty infiltration (myosteatosis), and/or low muscle mass (myopenia). The incidence of death and major adverse cardiovascular events were recorded during a median follow-up of 8.8 years. Multivariable analyses were performed accounting for age, sex, smoking status, myosteatosis, liver steatosis, myopenia, type 2 diabetes, obesity, visceral fat, and history of cardiovascular events. Results Overall, 8982 consecutive outpatients (mean age, 57 years ± 8 [SD]; 5008 female, 3974 male) were included. Abnormal body composition was found in 86% (434 of 507) of patients who died during follow-up. Myosteatosis was found in 278 of 507 patients (55%) who died (15.5% absolute risk at 10 years). Myosteatosis, obesity, liver steatosis, and myopenia were associated with increased mortality risk (hazard ratio [HR]: 4.33 [95% CI: 3.63, 5.16], 1.27 [95% CI: 1.06, 1.53], 1.86 [95% CI: 1.56, 2.21], and 1.75 [95% CI: 1.43, 2.14], respectively). In 8303 patients (excluding 679 patients without complete data), after multivariable adjustment, myosteatosis remained associated with increased mortality risk (HR, 1.89 [95% CI: 1.52, 2.35]; P < .001). Conclusion Artificial intelligence-based profiling of body composition from routine abdominal CT scans identified myosteatosis as a key predictor of mortality risk in asymptomatic adults. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Tong and Magudia in this issue.

Colon Cancer Screening Methods: 2023 Update.

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. National screening guidelines have been implemented to identify and remove precancerous polyps before they become cancer. Routine CRC screening is advised for people with average risk starting at age 45 because it is a common and preventable malignancy.Various screening modalities are currently in use, ranging from stool-based tests (fecal occult blood test (FOBT), fecal immunochemical test (FIT), and FIT-DNA test), radiologic tests (computed tomographic colonography (CTC), double contrast barium enema), and visual endoscopic examinations (flexible sigmoidoscopy (FS), colonoscopy, and colon capsule endoscopy (CCE)) with their varying sensitivity and specificity. Biomarkers also play a vital role in assessing the recurrence of CRC. This review offers a summary of the current screening options, including biomarkers available to detect CRC, highlighting the benefits and challenges encompassing each screening modality.

Application of a multispecies probiotic reduces gastro-intestinal discomfort and induces microbial changes after colonoscopy.

Even after decades of research and pharmaceutical development, cancer is still one of the most common causes of death in the western population and the management of cancer will remain a major challenge of medical research. One of the most common types of cancer is colorectal cancer (CRC). Prevention by detection of early-stage precursors is the most reliable method to prevent CRC development. In dependence of age, familial predisposition, and other risk factors the preventative routine screening for CRC by colonoscopy should be performed at least twice in intervals of about ten years. Although colonoscopy is a life-saving clinical examination reducing both incidence and mortality of CRC significantly, it has still a bad reputation in the population as an uncomfortable procedure with unpleasant side effects lasting sometimes over days to weeks. These effects are most likely caused by the bowel preparation before colonoscopy, which is crucial for a successful colonoscopy with high quality. Beside pain, bleeding and other rare but severe complications of colonoscopy, cleaning of the intestinal mucosa alters the gut microbiome significantly and consistently. Abdominal pain, cramps, diarrhea, nausea, bloating, and constipation are common adverse events which can continue to affect patients for days or even weeks after the procedure. In this multicenter, placebo controlled, double blind clinical trial, we investigated the effect of an intervention with a multispecies probiotic formulation for 30 days on the adverse events due to bowel preparation. We show that the treatment of participants with the multispecies probiotic formulation decreases the number of days with constipation significantly, and reduced pain, bloating, diarrhea, and general discomfort. 16S based amplicon analyses reveal recovery of administered probiotic strains from stool samples and differences in alpha diversity dynamics with higher variability in the probiotic group compared to the placebo group. In conclusion, the probiotic ameliorates the side effects after colonoscopy and might be an important supplement to increase acceptance of this life-saving preventative examination. Further, we present here for the first time that probiotic intervention of only 30 days affects alpha diversity parameters in stool samples.

Recurrent posterior fossa group A (PFA) ependymoma in a young child with constitutional mismatch repair deficiency (CMMRD).

Recurrent posterior fossa group A (PFA) ependymoma in a young child with constitutional mismatch repair deficiency (CMMRD).

Rates of Routine Cancer Screening and Diagnosis Before vs After the COVID-19 Pandemic

This cross-sectional study analyzes patterns in the rates of routine screening and diagnosis for breast, cervical, and colorectal cancer before and after the COVID-19 pandemic.

Diagnostic accuracy of the CxPREVENTIVE Colon model for early detection of colorectal cancer.

e15518 Background: Despite different available methods for colorectal cancer (CRC) screening and their proven benefits, morbidity, and mortality of this malignancy are still high, partly due to technical limitations and low compliance with screening. The aim of the present study was to assess the diagnostic accuracy for early detection of CRC using a modeling algorithm based on multiple blood and urine biomarkers. Methods: In this retrospective cohort study, clinical and blood and urine markers-based algorithms with predefined cutoff values were applied to a generally healthy asymptomatic outpatient cohort of adults aged 50 years or older undergoing colonoscopy and histopathology for routine colorectal cancer screening. We used a modeling algorithm based on two different frameworks (Multiple Biomarkers Disease Activity Algorithm MBDAA [Bioprognos], and Artificial Intelligence Recursive Algorithm AIRA [Mintlot] both in Barcelona, Spain). Both algorithms compute information from a wide number of analytes, tumor markers (AFP, CA 19.9, CA 72.4, CA 125, CEA, Cyr61, NGAL, EGFR and 8-OHdG), and additional clinical data (age, weight, height, and BMI). MBDAA includes Barcelona Criteria (four criteria to correctly interpret the cause of the increase in tumor markers, benign or malignant, defined by the Spanish Society of Clinical Biochemistry and Molecular Pathology, Commission of Biological Markers of Cancer). To assess the association between the modelling algorithm and downstream diagnosis we used logistic regression to compute receiver operating characteristic curves (ROC). Exact binomial confidence limits were calculated to test accuracy, sensitivity, and specificity. Results: 221 people (median age 63 yr. [IQR 49-77]; 107 [49%] women and 114 [51%] men) who underwent colonoscopy at the Juan Ramón Jiménez Hospital (Huelva, Spain), were included in this analysis. Based on colonoscopy and histopathologic findings, CRC was diagnosed in 45 (20%) patients, colonic polyposis in 56 (25%), inflammatory bowel disease in 37 (17%), and absence of pathological findings (control group) was seen in 83 (38%). The diagnostic intervention for CRC yielded an area under the curve (AUC) of 1 among the entire specimen set, accuracy 1 (95% CI 0.996,1), Se 1 (0.988, 1) and Sp 1 (0.997, 1). Besides, the algorithm also performed very well in the identification of polyps with an accuracy 1 (95% CI, 0.967 to 1), Se of 1 (0.991, 1) and of Sp 1 (0.996, 1), as well in the diagnosis of inflammatory bowel disease with an accuracy of 1 (0.968 to 1), Se of 1 (0.986, 1) and Sp of 1 (0.997, 1). Conclusions: Using colonoscopy as a gold standard, our data suggest that an innovative newly designed non-invasive blood and urine-based biomarker algorithm CxPREVENTIVE Colon may provide a timely diagnosis of CRC with very high accuracy. Our findings warrant further investigation, and we are planning large-scale (n 10,000), fully powered study to inform clinical practice.

Fully Automated Abdominal CT Biomarkers for Type 2 Diabetes Using Deep Learning.

Background CT biomarkers both inside and outside the pancreas can potentially be used to diagnose type 2 diabetes mellitus. Previous studies on this topic have shown significant results but were limited by manual methods and small study samples. Purpose To investigate abdominal CT biomarkers for type 2 diabetes mellitus in a large clinical data set using fully automated deep learning. Materials and Methods For external validation, noncontrast abdominal CT images were retrospectively collected from consecutive patients who underwent routine colorectal cancer screening with CT colonography from 2004 to 2016. The pancreas was segmented using a deep learning method that outputs measurements of interest, including CT attenuation, volume, fat content, and pancreas fractal dimension. Additional biomarkers assessed included visceral fat, atherosclerotic plaque, liver and muscle CT attenuation, and muscle volume. Univariable and multivariable analyses were performed, separating patients into groups based on time between type 2 diabetes diagnosis and CT date and including clinical factors such as sex, age, body mass index (BMI), BMI greater than 30 kg/m2, and height. The best set of predictors for type 2 diabetes were determined using multinomial logistic regression. Results A total of 8992 patients (mean age, 57 years ± 8 [SD]; 5009 women) were evaluated in the test set, of whom 572 had type 2 diabetes mellitus. The deep learning model had a mean Dice similarity coefficient for the pancreas of 0.69 ± 0.17, similar to the interobserver Dice similarity coefficient of 0.69 ± 0.09 (P = .92). The univariable analysis showed that patients with diabetes had, on average, lower pancreatic CT attenuation (mean, 18.74 HU ± 16.54 vs 29.99 HU ± 13.41; P < .0001) and greater visceral fat volume (mean, 235.0 mL ± 108.6 vs 130.9 mL ± 96.3; P < .0001) than those without diabetes. Patients with diabetes also showed a progressive decrease in pancreatic attenuation with greater duration of disease. The final multivariable model showed pairwise areas under the receiver operating characteristic curve (AUCs) of 0.81 and 0.85 between patients without and patients with diabetes who were diagnosed 0-2499 days before and after undergoing CT, respectively. In the multivariable analysis, adding clinical data did not improve upon CT-based AUC performance (AUC = 0.67 for the CT-only model vs 0.68 for the CT and clinical model). The best predictors of type 2 diabetes mellitus included intrapancreatic fat percentage, pancreatic fractal dimension, plaque severity between the L1 and L4 vertebra levels, average liver CT attenuation, and BMI. Conclusion The diagnosis of type 2 diabetes mellitus was associated with abdominal CT biomarkers, especially measures of pancreatic CT attenuation and visceral fat. © RSNA, 2022 Online supplemental material is available for this article.

Abstract PO-160: Associations between diet and food security with colorectal cancer-based health disparity among African Americans

Abstract Introduction. African Americans (AAs) have a colorectal cancer (CRC)-based health disparity. However, AAs had higher screening test usage than non-Hispanic whites (NHWs) in Arkansas in 2016. Additionally, CRC is of interest in Arkansas because geographic areas such as the Delta regions in Arkansas remain mortality hotspots. Also, certain lifestyle factors such as diet, alcohol and tobacco use, and physical activity have been associated with CRC risk. Our goal is to examine the association between colorectal health, diet, and sociodemographics related to access to adequate food, to understand the factors involved in the CRC health disparity among AAs. Method. We are recruiting participants who have recently (2019-2021) received a colonoscopy. These participants are filling out surveys related to their demographics, socioeconomic status, health, family history, lifestyle, and diet, as well as collecting a stool sample at home for our future untargeted metabolomic analysis. For this preliminary analysis, we have focused on self-report survey data to determine which factors are associated with colorectal health and race. Results. We used t-tests with Bonferroni correction and chi-square test with statistical significance at p&amp;lt;0.05. The comparisons were healthy vs. polyp(s), healthy vs. cancer, and polyp(s) vs. cancer. The cancer group had statistically lower percentages of having gone to or completed college, and of having hourly or salaried wages as well as higher percentages of $25,000/year or less in household income, overweight BMI of 25-30, family history of CRC, and ever smoked at least 100 cigarettes. In addition, all participants in the cancer group had ever used tobacco products and not lifted weights for physical activity in the last year. Also, the polyp(s) group had the highest percentage engaging in light physical activity, and the control group had the highest percentage of current use of cigarettes every day. We also compared the food- and nutrient-level data. Coumestrol was found to be significantly higher among the healthy group vs. polyp(s). Starch, starchy vegetables, phosphorous, zinc, and pinitol were found to be significant when comparing healthy vs. cancer, and all but pinitol were found to be higher among the cancer group. Also, starchy and total vegetables, trans-hexadecenoic acid, cis-9,trans-11 conjugated linoleic acid, and pinitol were found to be significant between polyp(s) vs. cancer, and all but pinitol were found to be higher among the cancer group. In addition, 37 food- and nutrient-level data points were significantly higher among NHW participants vs. AAs. Conclusion. CRC has minimal symptoms, and that is why routine CRC screening is important. From our findings, targeted education related to risk factors for CRC should be implemented among all people, especially on vegetable and fruit consumption, tobacco use, physical activity, and appropriate screening. Additional importance should be focused on high-risk individuals such as AAs and those with a family history of CRC. Citation Format: Jonathan A. Laryea, Eryn K. Matich, Ping-Ching Hsu, Joseph Su. Associations between diet and food security with colorectal cancer-based health disparity among African Americans [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-160.

Abstract PR-01: Association of Affordable Care Act Medicaid expansions with healthcare access and utilization among people who smoke

Abstract Background: People who smoke have a higher risk of developing cancer and disproportionately lower incomes which worsens healthcare access and health outcomes. The Affordable Care Act expanded Medicaid eligibility to adults with income up to 138% of the federal poverty line. It is unknown if and how Medicaid expansions changed healthcare access, preventive service use, and health behaviors. Also, it is unknown whether expansions impacted income or racial/ethnic disparities in these measures, given historically lower healthcare access and utilization in lower income people and people of color. Methods: Data were from the nationally representative Behavioral Risk Factor Surveillance System surveys between 2011-2019 of adults ages 18-64 years who currently smoked cigarettes and former smokers who had quit in the past year (n=580,858). Generalized difference-in-differences (DID) analyses using logistic regression models examined the association of Medicaid expansions (staggered time-varying exposure, 34 states expanded as of December 2019) with healthcare access (insurance coverage, care affordability, usual source of care), preventive service use (routine checkup, flu shot, HIV test, breast and colorectal cancer screening, cholesterol check, dentist visit), and health/risk behaviors (heavy alcohol drinking, obesity), including cessation behaviors (past-year quit attempt, successful cessation for &amp;gt;3 months). Income and race/ethnicity differences were also tested. Results: Among people who smoke, Medicaid expansions were associated with healthcare access and preventive care utilization improvements, but not health behaviors, including cessation. Expansions resulted in narrowing of disparities in several measures across income levels and Black vs. White people in expansion states. For example, expansion associated gains in insurance coverage were significantly larger in low-income (expansion: 74.6% vs. nonexpansion: 60.8%; DID: 13.8% 95% CI: 12.8, 14.8%) than high-income (insurance: 87.5% vs. 93.7%, DID: -6.2% points 95% CI: -7.2, -5.2%); and in Black people (82.6% vs. 74.6%, DID: 7.9% points 95% CI: 6.3, 9.5%) than White people (79.5% vs. 75.7%; DID: 3.8%, 95% CI: 3, 4.6%). Medicaid expansions gains were also larger among lower than higher income people for all in preventive care utilization measures studied; and uptake of flu shots, mammograms, and HIV tests were larger in Black than White people. Significant gains in multiple measures were also observed for Hispanic and American Indian/Alaska Native people who smoke, but changes were generally no different than White people. Conclusions: Among people who smoke, Medicaid expansions improved healthcare access and preventive services use. Expansions were also associated with a reduction, but not elimination, of income and Black-White disparities in healthcare access and utilization. Despite insurance and preventive service gains, expansions were not associated with cessation behaviors, signaling the need for improving comprehensive cessation treatments in Medicaid expansion programs. Citation Format: Priti Bandi, Samuel Asare, J. Lee Westmaas, Nigar Nargis, Robin Yabroff, Ahmedin Jemal, Xuesong Han, Stacey Fedewa. Association of Affordable Care Act Medicaid expansions with healthcare access and utilization among people who smoke [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PR-01.

Colorectal cancer in the 45-to-50 age group in the United States: a National Cancer Database (NCDB) analysis

BackgroundAmid increasing awareness of early-onset colorectal cancer (CRC), guidelines in the United States (US) recently lowered the recommended routine CRC screening age from 50 to 45 in average-risk individuals. There are little data on the number of patients in this age group diagnosed with CRC prior to these changes. Our objective was to audit the historic CRC case trends and impact of CRC in the 45-to-50-year-old category prior to new screening recommendations.MethodsColorectal adenocarcinoma cases in 45-to-50-year-old patients were queried from the NCDB (2004–2017). Cases were stratified by sex, race, and site. The disability-adjusted lost years (DALY) and lost earnings were estimated. The average annual percentage changes (AAPC) of CRC incidence were estimated using jointpoint analysis. The main outcome measures were DALY and lost earnings. Secondary outcome measures were the 2004–2017 AAPC and the cumulative incidence of potential CRC cases in the 45-to-50 cohort through 2030 without guideline changes.Results67,442 CRC patients in the 45-to-50 demographic were identified. The CRC burden resulted 899,905 DALY and $17 billion in lost earnings. The 2004–2017 AAPC was 1.6%, with an estimated 13-year increase of 25%. There were sex-, race-, and anatomic site-specific discrepancies with estimated 13-year increases of 30% for males, 110% for American Indian/ Alaska Natives/ Asian American/ Pacific Islander races, and 31% for rectal cancer by 2030.ConclusionCRC has been steadily increasing in the 45-to-50 age group, with tremendous disability and cost ensuing. There is great potential benefit from lowering the recommended routine CRC screening age to 45. Targeted intervention could ensure the most vulnerable segments benefit from the new guidelines, in both reducing the incidence and improving survivorship in CRC patients.Graphical abstract

Cost-Effectiveness of Colorectal Cancer Genetic Testing.

Colorectal cancer (CRC) remains the second leading cause of cancer-related deaths worldwide. Approximately 3–5% of CRCs are associated with hereditary cancer syndromes. Individuals who harbor germline mutations are at an increased risk of developing early onset CRC, as well as extracolonic tumors. Genetic testing can identify genes that cause these syndromes. Early detection could facilitate the initiation of targeted prevention strategies and surveillance for CRC patients and their families. The aim of this study was to determine the cost-effectiveness of CRC genetic testing. We utilized a cross-sectional design to determine the cost-effectiveness of CRC genetic testing as compared to the usual screening method (iFOBT) from the provider’s perspective. Data on costs and health-related quality of life (HRQoL) of 200 CRC patients from three specialist general hospitals were collected. A mixed-methods approach of activity-based costing, top-down costing, and extracted information from a clinical pathway was used to estimate provider costs. Patients and family members’ HRQoL were measured using the EQ-5D-5L questionnaire. Data from the Malaysian Study on Cancer Survival (MySCan) were used to calculate patient survival. Cost-effectiveness was measured as cost per life-year (LY) and cost per quality-adjusted life-year (QALY). The provider cost for CRC genetic testing was high as compared to that for the current screening method. The current practice for screening is cost-saving as compared to genetic testing. Using a 10-year survival analysis, the estimated number of LYs gained for CRC patients through genetic testing was 0.92 years, and the number of QALYs gained was 1.53 years. The cost per LY gained and cost per QALY gained were calculated. The incremental cost-effectiveness ratio (ICER) showed that genetic testing dominates iFOBT testing. CRC genetic testing is cost-effective and could be considered as routine CRC screening for clinical practice.