Limburg, Paul J

Abstract Globally, gastric adenocarcinoma is the fourth leading cause of cancer mortality and a major cancer disparity in the United States. Chemoprevention strategies are lacking for high-risk individuals with gastric premalignant conditions (GPMC). Curcumin, the principal curcuminoid in turmeric, exerts immunomodulatory effects in the epithelium and against Helicobacter pylori, and studies suggest chemoprevention potential. We conducted a double-blind, phase IIa randomized controlled trial in high-risk populations in Puerto Rico and Honduras. We investigated the utility of a bioavailable formulation of curcumin (Meriva) among individuals with H. pylori–negative GPMC, specifically, multifocal atrophic gastritis (MAG) or gastric intestinal metaplasia (GIM). Patients were 1:1 randomized to 1,000 mg Meriva daily or placebo for a 6-month intervention with endoscopy at baseline and 6 months. Outcomes included assessment of epithelial cytokine and chemokine levels, histology, and DNA damage as assessed by γ-H2AX phosphorylation IHC. Of the 110 subjects screened, 50 participants were randomized, and 48 completed the trial. A significant reduction in gastric mucosal IL1β levels from baseline in the gastric body, the primary endpoint, was observed in the Meriva group (P = 0.032). Changes in epithelial IL8, TNFα, and inducible protein 10 levels and gastric mucosal histology and DNA damage (secondary endpoints) were similar between arms. Curcumin (Meriva) was safe, well-tolerated, and showed potential as a curcuminoid chemoprevention agent in H. pylori–negative patients with GPMC. A potential reduction in gastric inflammation as measured by gastric mucosal IL1β levels was observed. Further studies are warranted, including studies in H. pylori–positive individuals, based upon the curcuminoid direct effects on H. pylori. Prevention Relevance: Gastric adenocarcinoma is a leading cause of cancer mortality worldwide. Chemoprevention candidates for GPMCs are limited. This randomized phase IIa trial evaluated a bioavailable curcumin formulation in high-risk individuals with MAG and GIM. The results support further study of curcuminoids for gastric cancer risk reduction. See related Spotlight, p. 387 See related article by Morgan et al., p. 391

ABSTRACT Background Several colorectal cancer (CRC) screening modalities are guideline-recommended in the United States, yet they vary considerably in screening interval and real-world adherence. As a result, single-round test performance may not reflect cumulative effectiveness over time. This study compared the 10-year longitudinal outcomes of two CRC screening strategies— triennial next-generation multitarget stool DNA testing (ng mt-sDNA) and decennial screening colonoscopy. Methods This study used the validated, microsimulation-based Colorectal Cancer and Adenoma Incidence and Mortality (CRC-AIM) model to estimate 10-year cumulative outcomes for two guideline-recommended screening strategies: triennial ng mt-sDNA and decennial colonoscopy. Model inputs included test-specific performance and real-world adherence. Outcomes included CRC and precancerous lesions detected, CRC mortality reductions, and life-years gained (LYG). Sensitivity analyses examined the effects of varying both screening adherence and follow-up colonoscopy adherence. Results Over 10 years per 1,000 individuals offered screening, the ng mt-sDNA screening test detected 13% more precancerous lesions and 11% more CRC cases than colonoscopy, with a greater proportion of CRCs identified through screening rather than symptomatic detection. ng mt-sDNA resulted in greater CRC mortality reduction (33% vs 20%) and 62% more life-years gained, with consistent findings across sensitivity analyses. Conclusions With real-world adherence, screening with triennial ng mt-sDNA demonstrates superior cumulative effectiveness compared with decennial colonoscopy, driven by higher adherence and favorable longitudinal performance. These findings support the expanded use of noninvasive stool-based screening to reduce CRC mortality and alleviate capacity constraints associated with colonoscopy-based screening. Broader adoption of ng mt-sDNA may enhance population-level CRC prevention by increasing participation and improving early detection across the screening eligible population. Plain language summary Colorectal cancer screening tests are recommended at different time intervals and completed at different adherence rates in clinical practice. The analysis used a validated simulation model to compare 10-year outcomes of triennial next-generation multi-target stool DNA test (ng mt-sDNA) with a single colonoscopy, accounting for real-world screening and follow-up colonoscopy adherence. Our findings indicate that repeated ng mt-sDNA provides greater cumulative screening effectiveness than colonoscopy over a 10-year period.

Abstract Background Recommended noninvasive strategies for average-risk colorectal cancer (CRC) screening include multitarget stool DNA and fecal immunochemical test from ages 45 to 75 years. With new clinical trials, performance data for next-generation multitarget stool DNA, multitarget stool RNA, and blood-based screening tests are now available. This decision analytical model study evaluated the estimated benefit-to-burden ratio by means of efficient frontiers for noninvasive established and emerging CRC screening strategies. Methods Outcomes were estimated using the Colorectal Cancer and Adenoma Incidence and Mortality microsimulation model for average-risk individuals in the United States. Screening strategies were next-generation multitarget stool DNA (an updated marker panel), fecal immunochemical tests, multitarget stool RNA, or blood-based tests every 1-3 years, over various age ranges. Test performance inputs were derived from recent large clinical trials. A strategy was deemed efficient if no other strategy provided more life-years gained with equivalent or fewer lifetime colonoscopies and near-efficient if within 3 days of life-years gained of the efficient frontier. Results All modeled screening strategies resulted in life-years gained vs no screening. No strategy using blood-based tests was efficient or near-efficient. Overall, 10 strategies were efficient (6 next-generation multitarget stool DNA and 4 fecal immunochemical tests), including 2 strategies among those ages 45-75 years (biennial and triennial next-generation multitarget stool DNA). Overall, 22 strategies were near-efficient, including 4 strategies among those ages 45-75 years (annual, biennial, or triennial fecal immunochemical test; annual next-generation multitarget stool DNA). Conclusion Based on this modeling study, next-generation multitarget stool DNA was the only noninvasive screening test at guideline-endorsed interval and age-recommended ranges that was deemed efficient. Blood-based and multitarget stool RNA strategies were deemed not efficient for primary screening.

Abstract The aim was to assess whether subject’s participation in early-phase chemoprevention trials was satisfactory and identify features associated with subjects’ satisfaction. Thirteen trials that investigated a range of candidate agents from 2006 to 2021 by the Cancer Prevention Network were included. The five-item “Was It Worth It?” (WIWI) questionnaire was administered to all subjects at the end of each trial’s intervention or at early termination. Satisfied overall was defined as a participant response of “yes” to the first three questions. Six hundred ninety-one participants from the United States, Canada, Puerto Rico, and Honduras enrolled on a trial. Six hundred fifty-two (94.4%) completed the WIWI questionnaire. Of these, 493 (75.6%) were White, non-Hispanic/Latino; 39 (6.0%) Black, non-Hispanic/Latino; 98 (15.0%) Hispanic/Latino; and 8 (1.2%) of another race/ethnicity. One hundred ninety-three were women (29.6%), 121 (17.5%) were ≥65 years, and 517 (79.3%) participated in a placebo-controlled trial. Eighty-five percent indicated being satisfied overall. Compared with White, non-Hispanic/Latino, the odds of not satisfied overall were 2.96 times higher for Black/Asian/>1 race, non-Hispanic/Latino (P < 0.001) and 0.40 times lower for Hispanic/Latino (P = 0.004). The odds of not satisfied overall was 1.9 times higher when the number of preintervention adverse events experienced was ≥1 (P = 0.012), 1.8 times higher when the percentage of the intervention duration with adverse events was >5% (P = 0.024), and 7.4 times higher for subjects who terminated the intervention early (P < 0.001). These findings can inform the design of future chemoprevention trials and help investigators improve accrual, retention, adherence, and diversity in this underexplored research setting. Prevention Relevance: The five-item “WIWI?” questionnaire, which captures the participant-reported experience of trial participation, gives the subject a voice in the development of new chemopreventative agents. This study in 652 subjects looked at satisfaction with participation in early-phase chemoprevention trials for higher-risk, cancer-free men and women. See related Spotlight, p. 7

Abstract The substantial carbon footprint imparted by medical services warrants increased attention to their environmental impact. National guideline organizations such as the US Preventive Services Task Force (USPSTF) recommend multiple modalities for average-risk colorectal cancer (CRC) screening with varying resource intensity. The aim of this study was to quantify the environmental burden for 2 of the most used CRC screening modalities, colonoscopy and the multi-target stool DNA (mt-sDNA) test. A validated CRC microsimulation model was used to estimate the number of screening and follow-up tests for a cohort of 1 million average-risk individuals who underwent screening between ages 45 and 75. Component resources used for mt-sDNA, including waste products, energy, and transportation for colonoscopy and mt-sDNA, were collected from January 1, 2023, to January 1, 2024, and converted to carbon-equivalent emissions. Resources used for colonoscopy were captured from the literature. Resources devoted to screening colonoscopy were substantially (59%) higher than those to mt-sDNA, even when including follow-up colonoscopy. Of note, follow-up colonoscopy accounted for the majority (64%) of total emissions for the mt-sDNA screening strategy. Compared with colonoscopy screening, mt-sDNA substantially reduces the carbon emissions attributable to population-level CRC screening. Environmental impact should be included as a factor when choosing among guideline-recommended CRC screening strategies.

Abstract Gastric adenocarcinoma (GAC) is the fourth leading global cause of cancer mortality and leading infection-associated cancer. High-incidence regions of GAC include Latin America and Eastern Asia. Immigrants from high-incidence regions maintain their GAC risk. GAC is a major U.S. cancer disparity, and its incidence rates are 2 to 10 times higher in non-White populations. Emerging guidelines recommend 3-year surveillance endoscopy for patients with high-risk gastric premalignant conditions (GPMC). Clinical trials of GPMC chemoprevention agents are lacking. We conducted a NCI Division of Cancer Prevention–funded, phase II placebo-controlled chemoprevention trial in patients with GPMCs (atrophic gastritis and intestinal metaplasia) with a highly bioavailable preparation of curcuminoids (Meriva). The trial sites in Puerto Rico and rural Honduras had important characteristics: (i) representative Caribbean and Mesoamerican populations, linked to large U.S. immigrant populations; (ii) high prevalence of Helicobacter pylori infection and GPMCs; (iii) the absence of turmeric and curcuminoids in local diets; and (iv) proven bidirectional collaboration with U.S. academic institutions. H. pylori–negative patients with GPMCs were randomized to the study drug (500 mg po bid) or placebo for 180 days (NCT02782949), with primary outcomes based upon histologic parameters. Principal study challenges included (i) an international regulatory environment; (ii) research infrastructure strengthening, particularly in Central America; (iii) participant recruitment in Honduras, wherein only 10% to 15% are H. pylori negative; (iv) the COVID-19 pandemic; and (v) natural disasters (three hurricanes). There were no losses to follow-up related to the pandemic or natural disasters. In conclusion, the south–south partnership provides a model for chemoprevention and translational studies in Latino populations with prevalent cancers, such as GAC.

Abstract Colorectal cancer is the second leading cause of cancer-related mortality in adults in the United States. Despite compelling evidence of improved outcomes in colorectal cancer, screening rates are not optimal. This study aimed to characterize colorectal cancer screening trends over the last two decades and assess the impact of various screening modalities on overall colorectal cancer screening rates. Using National Health Interview Survey data from 2005 to 2021, we examined colorectal cancer screening [colonoscopy, multitarget stool DNA (mt-sDNA), fecal occult blood test (FOBT)/fecal immunochemical test, sigmoidoscopy, CT colonography] rates among adults ages 50–75 years (n = 85,571). A pseudo-time-series cross-sectional (pseudo-TSCS) analysis was conducted including a random effects generalized least squares regression model to estimate the relative impact of each modality on changes in colorectal cancer screening rates. Among 50 to 75 year olds, the estimated colorectal cancer screening rate increased from 47.7% in 2005 to 69.9% in 2021, with the largest increase between 2005 and 2010 (47.7%–60.7%). Rates subsequently plateaued until 2015 but increased from 63.5% in 2015 to 69.9% in 2018. This was primarily driven by the increased use of mt-sDNA (2.5% in 2018 to 6.6% in 2021). Pseudo-TSCS analysis results showed that mt-sDNA contributed substantially to the increase in overall screening rates (77.3%; P < 0.0001) between 2018 and 2021. While colorectal cancer screening rates increased from 2005 to 2021, they remain below the 80% goal. The introduction of mt-sDNA, a noninvasive screening test may have improved overall rates. Sustained efforts are required to further increase screening rates to improve patient outcomes and offering a range of screening options is likely to contribute to achieving this goal. Prevention Relevance: This retrospective study highlights the importance of convenient stool-based colorectal cancer screening options to achieve the national goal of 80% for overall colorectal cancer screening rates. Empowering screening-eligible individuals with a choice for their colorectal cancer screening tests is imperative.