Summary of Veterans Health Administration Cancer Data Sources.

Objectives: The Veterans Health Administration (VHA) is a leader in generating transformational research across the cancer care continuum. Given the extensive body of cancer-related literature utilizing VHA data, our objectives are to: (1) describe the VHA data sources available for conducting cancer-related research, and (2) discuss examples of published cancer research using each data source. Methods: We identified commonly used data sources within the VHA and reviewed previously published cancer-related research that utilized these data sources. In addition, we reviewed VHA clinical and health services research web pages and consulted with a multidisciplinary group of cancer researchers that included hematologist/oncologists, health services researchers, and epidemiologists. Results: Commonly used VHA cancer data sources include the Veterans Affairs (VA) Cancer Registry System, the VA Central Cancer Registry (VACCR), the Corporate Data Warehouse (CDW)-Oncology Raw Domain (subset of data within the CDW), and the VA Cancer Care Cube (Cube). While no reference standard exists for cancer case ascertainment, the VACCR provides a systematic approach to ensure the complete capture of clinical history, cancer diagnosis, and treatment. Like many population-based cancer registries, a significant time lag exists due to constrained resources, which may make it best suited for historical epidemiologic studies. The CDW-Oncology Raw Domain and the Cube contain national information on incident cancers which may be useful for case ascertainment and prospective recruitment; however, additional resources may be needed for data cleaning. Conclusions: The VHA has a wealth of data sources available for cancer-related research. It is imperative that researchers recognize the advantages and disadvantages of each data source to ensure their research questions are addressed appropriately.

Longitudinal Patterns of Multimorbidity in Gulf War Era Veterans With and Without Gulf War Illness.

Objectives: To examine whether severe Gulf War illness (SGWI) case status was associated with longitudinal multimorbidity patterns. Methods: Participants were users of the Veteran Health Administration Health Care System drawn from the Gulf War Era Cohort and Biorepository (n = 840). Longitudinal measures of multimorbidity were constructed using (1) electronic health records (Charlson Comorbidity Index; Elixhauser; and Veterans Affairs Frailty Index) from 10/1/1999 to 6/30/2023 and (2) self-reported medical conditions (Deficit Accumulation Index) since the war until the survey date. Accelerated failure time models examined SGWI case status as a predictor of time until threshold level of multimorbidity was reached, adjusted for age and sociodemographic and military characteristics. Results: Models, adjusted for covariates, revealed that (1) relative to the SWGI- group, the SGWI+ group was associated with an accelerated time for reaching each threshold and (2) the relationship between SGWI and each threshold was not moderated by age. Discussion: Findings suggest that veterans with SGWI experienced accelerated aging.

Lung Cancer Survival Trends in the Veterans Health Administration.

INTRODUCTION: Lung cancer survival is improving in the United States. We investigated whether there was a similar trend within the Veterans Health Administration (VHA), the largest integrated healthcare system in the United States. MATERIALS AND METHODS: Data from the Veterans Affairs Central Cancer Registry were analyzed for temporal survival trends using Kaplan-Meier estimates and linear regression. RESULTS: A total number of 54,922 Veterans were identified with lung cancer diagnosed from 2010 to 2017. Histologies were classified as non-small-cell lung cancer (NSCLC) (64.2%), small cell lung cancer (SCLC) (12.9%), and 'other' (22.9%). The proportion with stage I increased from 18.1% to 30.4%, while stage IV decreased from 38.9% to 34.6% (both P < .001). The 3-year overall survival (OS) improved for stage I (58.6% to 68.4%, P < .001), stage II (35.5% to 48.4%, P < .001), stage III (18.7% to 29.4%, P < .001), and stage IV (3.4% to 7.8%, P < .001). For NSCLC, the median OS increased from 12 to 21 months (P < .001), and the 3-year OS increased from 24.1% to 38.3% (P < .001). For SCLC, the median OS remained unchanged (8 to 9 months, P = .10), while the 3-year OS increased from 9.1% to 12.3% (P = .014). Compared to White Veterans, Black Veterans with NSCLC had similar OS (P = .81), and those with SCLC had higher OS (P = .003). CONCLUSION: Lung cancer survival is improving within the VHA. Compared to White Veterans, Black Veterans had similar or higher survival rates. The observed racial equity in outcomes within a geographically and socioeconomically diverse population warrants further investigation to better understand and replicate this achievement in other healthcare systems.

Military exposures and Gulf War illness in veterans with and without posttraumatic stress disorder.

Gulf War illness (GWI) is a chronic multisymptom disorder of unknown etiology that is believed to be caused by neurotoxicant exposure experienced during deployment to the Gulf War. Posttraumatic stress disorder (PTSD) covaries with GWI and is believed to play a role in GWI symptoms. The present study examined the association between self-reported military exposures and GWI, stratified by PTSD status, in veterans from the Gulf War Era Cohort and Biorepository who were deployed to the Persian Gulf during the war. Participants self-reported current GWI and PTSD symptoms as well as military exposures (e.g., pyridostigmine [PB] pills, pesticides/insecticides, combat, chemical attacks, and oil well fires) experienced during the Gulf War. Deployed veterans' (N = 921) GWI status was ascertained using the Centers for Disease Control and Prevention definition. Individuals who met the GWI criteria were stratified by PTSD status, yielding three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression, adjusted for covariates, was used to examine associations between GWI/PTSD groups and military exposures. Apart from insect bait use, the GWI+/PTSD+ group had higher odds of reporting military exposures than the GWI+/PTSD- group, adjusted odds ratio (aOR) = 2.15, 95% CI [1.30, 3.56]-aOR = 6.91, 95% CI [3.39, 14.08]. Except for PB pills, the GWI+/PTSD- group had a higher likelihood of reporting military exposures than the GWI- group, aOR = 2.03, 95% CI [1.26, 3.26]-aOR = 4.01, 95% CI [1.57, 10.25]. These findings are consistent with roles for both PTSD and military exposures in the etiology of GWI.

Health outcomes and healthcare resource utilization among Veterans with stage IV non-small cell lung cancer treated with second-line chemotherapy versus immunotherapy.

BACKGROUND: Until recently, multi-agent chemotherapy (CT) was the standard of care for patients with advanced non-small cell lung cancer (NSCLC). Clinical trials have confirmed benefits in overall survival (OS) and progression-free survival with immunotherapy (IO) compared to CT. This study compares real-world treatment patterns and outcomes between CT and IO administrations in second-line (2L) settings for patients with stage IV NSCLC. MATERIALS AND METHODS: This retrospective study included patients in the United States Department of Veterans Affairs healthcare system diagnosed with stage IV NSCLC during 2012-2017 and receiving IO or CT in the 2L. Patient demographics and clinical characteristics, healthcare resource utilization (HCRU), and adverse events (AEs) were compared between treatment groups. Logistic regression was used to examine differences in baseline characteristics between groups, and inverse probability weighting multivariable Cox proportional hazard regression was used to analyze OS. RESULTS: Among 4,609 Veterans who received first-line (1L) therapy for stage IV NSCLC, 96% received 1L CT alone. A total of 1,630 (35%) were administered 2L systemic therapy, with 695 (43%) receiving IO and 935 (57%) receiving CT. Median age was 67 years (IO group) and 65 years (CT group); most patients were male (97%) and white (76-77%). Patients administered 2L IO had a higher Charlson Comorbidity Index than those administered CT (p = 0.0002). 2L IO was associated with significantly longer OS compared with CT (hazard ratio 0.84, 95% CI 0.75-0.94). IO was more frequently prescribed during the study period (p < 0.0001). No difference in rate of hospitalizations was observed between the two groups. CONCLUSIONS: Overall, the proportion of advanced NSCLC patients receiving 2L systemic therapy is low. Among patients treated with 1L CT and without IO contraindications, 2L IO should be considered, as this supports potential benefit of IO for advanced NSCLC. The increasing availability and indications for IO will likely increase the administration of 2L therapy to NSCLC patients.

Medications Associated with Lower Mortality in a SARS-CoV-2 Positive Cohort of 26,508 Veterans.

BACKGROUND: Many severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive patients take commonly prescribed medications with properties which may affect mortality. OBJECTIVE: Assess if common medications postulated to affect clinical outcomes are associated with mortality in SARS-CoV-2 positive patients in the Veterans Health Administration (VHA). DESIGN: Observational national cohort analysis. PARTICIPANTS: Consecutive 26,508 SARS-CoV-2 positive Veterans (7% of 399,290 tested from March 1 to September 10, 2020) constitute the study cohort. MAIN MEASURES: The primary outcome was 30-day mortality from the first positive SARS-CoV-2 test date. In patients receiving medications or drug pairs within 2 weeks post-SARS-CoV-2 positive test, 30-day mortality was estimated as relative risk (RR) on the log-binomial scale or using multinomial models with and without adjusting for covariates. KEY RESULTS: The 26,508 SARS-CoV-2 positive patients were predominantly male (89%) and White (59%), and 82% were overweight/obese. Medications associated with decreased 30-day mortality risk included the following: metformin (aRR, 0.33; 95% CI, 0.25-0.43), colchicine, angiotensin-converting-enzyme inhibitors (ACEi), angiotensin II receptor blockers, statins, vitamin D, antihistamines, alpha-blockers, anti-androgens, and nonsteroidal anti-inflammatory drugs (aRR, 0.69; 95% CI, 0.61-0.78). The effect of co-prescribed medications on 30-day mortality risk revealed the lowest risk for combined statins and metformin (aRR, 0.21; 95% CI, 0.15-0.31), followed by ACEi and statins (aRR, 0.25; 95% CI, 0.18-0.35), ACEi and metformin (aRR, 0.26; 95% CI, 0.17-0.40), antihistamines and NSAIDs (aRR, 0.41; 95% CI, 0.32-0.52), and in men, combined alpha-blockers and anti-androgens (aRR, 0.51; 95% CI, 0.42-0.64). CONCLUSIONS: In this large national cohort, treatment of SARS-CoV-2 positive patients with individual or co-prescribed metformin and statins, ACEi and statins (or metformin) and other medications was associated with a markedly decreased 30-day mortality and can likely be continued safely. Clinical trials may assess their therapeutic benefit.

Longitudinal assessment of colonoscopy adverse events in the prospective Cooperative Studies Program no. 380 colorectal cancer screening and surveillance cohort.

BACKGROUND AND AIMS: Data are limited regarding colonoscopy risk during long-term, programmatic colorectal cancer screening and follow-up. We aimed to describe adverse events during follow-up in a colonoscopy screening program after the baseline examination and examine factors associated with increased risk. METHODS: Cooperative Studies Program no. 380 includes 3121 asymptomatic veterans aged 50 to 75 years who underwent screening colonoscopy between 1994 and 1997. Periprocedure adverse events requiring significant intervention were defined as major events (other events were minor) and were tracked during follow-up for at least 10 years. Multivariable odds ratios (ORs) were calculated for factors associated with risk of follow-up adverse events. RESULTS: Of 3727 follow-up examinations in 1983 participants, adverse events occurred in 105 examinations (2.8%) in 93 individuals, including 22 major and 87 minor events (examinations may have had >1 event). Incidence of major events (per 1000 examinations) remained relatively stable over time, with 6.1 events at examination 2, 4.8 at examination 3, and 7.2 at examination 4. Examinations with major events included 1 perforation, 3 GI bleeds requiring intervention, and 17 cardiopulmonary events. History of prior colonoscopic adverse events was associated with increased risk of events (major or minor) during follow-up (OR, 2.7; 95% confidence interval, 1.6-4.6). CONCLUSIONS: Long-term programmatic screening and surveillance was safe, as major events were rare during follow-up. However, serious cardiopulmonary events were the most common major events. These results highlight the need for detailed assessments of comorbid conditions during routine clinical practice, which could help inform individual decisions regarding the utility of ongoing colonoscopy follow-up.

Health-Related Quality of Life by Gulf War Illness Case Status.

This study examines how health-related quality of life (HRQOL) and related indices vary by Gulf War illness (GWI) case status. The study population included veterans from the Gulf War Era Cohort and Biorepository (n = 1116). Outcomes were physical and mental health from the Veterans RAND 12 and depression, post-traumatic stress (PTSD), sleep disturbance, and pain. Kansas (KS) and Centers for Disease Control and Prevention (CDC) GWI definitions were used. Kansas GWI derived subtypes included GWI (met symptom criteria; no exclusionary conditions (KS GWI: Sym+/Dx−)) and those without GWI: KS noncase (1): Sym+/Dx+, KS noncase (2): Sym−/Dx+, and noncase (3): Sym−/Dx−. CDC-derived subtypes included CDC GWI severe, CDC GWI mild-to-moderate and CDC noncases. Case status and outcomes were examined using multivariable regression adjusted for sociodemographic and military-related characteristics. Logistic regression analysis was used to examine associations between GWI case status and binary measures for depression, PTSD, and severe pain. The KS GWI: Sym+/Dx− and KS noncase (1): Sym+/Dx+ groups had worse mental and physical HRQOL outcomes than veterans in the KS noncase (2): Sym−/Dx+ and KS noncase (3): Sym−/Dx− groups (ps < 0.001). Individuals who met the CDC GWI severe criteria had worse mental and physical HRQOL outcomes than those meeting the CDC GWI mild-to-moderate or CDC noncases (ps < 0.001). For other outcomes, results followed a similar pattern. Relative to the less symptomatic comparison subtypes, veterans who met the Kansas symptom criteria, regardless of exclusionary conditions, and those who met the CDC GWI severe criteria experienced lower HRQOL and higher rates of depression, PTSD, and severe pain.

Screening Colonoscopy Findings Are Associated With Noncolorectal Cancer Mortality.

INTRODUCTION: Controversy exists regarding the impact of various risk factors on noncolorectal cancer (CRC) mortality in healthy screening populations. We examined the impact of known CRC risk factors, including baseline colonoscopy findings, on non-CRC mortality in a screening population. METHODS: Cooperative Studies Program (CSP) #380 is comprised of 3,121 veterans aged 50-75 years who underwent screening colonoscopy from 1994 to 97 and were then followed for at least 10 years or until death. Hazard ratios (HRs) for risk factors on non-CRC mortality were estimated by multivariate Cox proportional hazards. RESULTS: Current smoking (HR 2.12, 95% confidence interval [CI] 1.78-2.52, compared with nonsmokers) and physical activity (HR 0.89, 95% CI 0.84-0.93) were the modifiable factors most associated with non-CRC mortality in CSP#380. In addition, compared with no neoplasia at baseline colonoscopy, non-CRC mortality was higher in participants with ≥3 small adenomas (HR 1.43, 95% CI 1.06-1.94), advanced adenomas (HR 1.32, 95% CI 0.99-1.75), and CRC (HR 2.95, 95% CI 0.98-8.85). Those with 1-2 small adenomas were not at increased risk for non-CRC mortality (HR 1.15, 95% CI 0.94-1.4). DISCUSSION: In a CRC screening population, known modifiable risk factors were significantly associated with 10-year non-CRC mortality. Furthermore, those who died from non-CRC causes within 10 years were more likely to have had high-risk findings at baseline colonoscopy. These results suggest that advanced colonoscopy findings may be a risk marker of poor health outcomes. Integrated efforts are needed to motivate healthy lifestyle changes during CRC screening, particularly in those with high-risk colonoscopy findings and unaddressed risk factors.

Ten or More Cumulative Lifetime Adenomas Are Associated with Increased Risk for Advanced Neoplasia and Colorectal Cancer.

BACKGROUND: Colorectal cancer (CRC) screening guidelines recommend frequent colonoscopies and consideration of genetic testing in individuals with ≥10 cumulative adenomas. However, it is unclear how these guidelines apply to routine practice. AIMS: We estimated the proportion of participants found to have ≥10 cumulative adenomas in a screening population and described their outcomes of advanced neoplasia (AN), CRC, and extra-colonic malignancy. METHODS: We performed a secondary analysis of VA CSP#380, which includes 3121 veterans aged 50-75 who were followed up to 10 years after screening colonoscopy. We calculated the cumulative risk of ≥10 cumulative adenomas by Kaplan-Meier method. We compared baseline risk factors in those with and without ≥10 cumulative adenomas as well as the risk for AN (adenoma ≥1 cm, villous adenoma or high-grade dysplasia, or CRC) and extra-colonic malignancy by multivariate logistic regression. RESULTS: The cumulative risk of ≥10 cumulative adenomas over 10.5 years was 6.51% (95% CI 4.38%-9.62%). Age 60-69 or 70-75 at baseline colonoscopy was the only factors associated with the finding of ≥10 cumulative adenomas. Compared to those with 0-9 cumulative adenomas, participants with ≥10 cumulative adenomas were more likely to have had AN (OR 17.03; 95% CI 9.41-30.84), including CRC (OR 7.00; 95% CI 2.84-17.28), but not extra-colonic malignancies. CONCLUSIONS: Approximately 6.5% of participants in this screening population were found to have ≥10 cumulative adenomas over 10.5 years, which was uncommon before age 60. These participants were found to have AN and CRC significantly more often compared to those with lower cumulative adenomas.

Gene-Toxicant Interactions in Gulf War Illness: Differential Effects of the PON1 Genotype.

About 25-35% of United States veterans who fought in the 1990-1991 Gulf War report several moderate or severe chronic systemic symptoms, defined as Gulf War illness (GWI). Thirty years later, there is little consensus on the causes or biological underpinnings of GWI. The Gulf War Era Cohort and Biorepository (GWECB) was designed to investigate genetic and environmental associations with GWI and consists of 1343 veterans. We investigate candidate gene-toxicant interactions that may be associated with GWI based on prior associations found in human and animal model studies, focusing on SNPs in or near ACHE, BCHE, and PON1 genes to replicate results from prior studies. SOD1 was also considered as a candidate gene. CDC Severe GWI, the primary outcome, was observed in 26% of the 810 deployed veterans included in this study. The interaction between the candidate SNP rs662 and pyridostigmine bromide (PB) pills was found to be associated with CDC Severe GWI. Interactions between PB pill exposure and rs3917545, rs3917550, and rs2299255, all in high linkage disequilibrium in PON1, were also associated with respiratory symptoms. These SNPs could point toward biological pathways through which GWI may develop, which could lead to biomarkers to detect GWI or to better treatment options for veterans with GWI.

COVID-19-Associated Mortality in US Veterans with and without SARS-CoV-2 Infection.

BACKGROUND: We performed an observational Veterans Health Administration cohort analysis to assess how risk factors affect 30-day mortality in SARS-CoV-2-infected subjects relative to those uninfected. While the risk factors for coronavirus disease 2019 (COVID-19) have been extensively studied, these have been seldom compared with uninfected referents. METHODS: We analyzed 341,166 White/Black male veterans tested for SARS-CoV-2 from March 1 to September 10, 2020. The relative risk of 30-day mortality was computed for age, race, ethnicity, BMI, smoking status, and alcohol use disorder in infected and uninfected subjects separately. The difference in relative risk was then evaluated between infected and uninfected subjects. All the analyses were performed considering clinical confounders. RESULTS: In this cohort, 7% were SARS-CoV-2-positive. Age >60 and overweight/obesity were associated with a dose-related increased mortality risk among infected patients relative to those uninfected. In contrast, relative to never smoking, current smoking was associated with a decreased mortality among infected and an increased mortality in uninfected, yielding a reduced mortality risk among infected relative to uninfected. Alcohol use disorder was also associated with decreased mortality risk in infected relative to the uninfected. CONCLUSIONS: Age, BMI, smoking, and alcohol use disorder affect 30-day mortality in SARS-CoV-2-infected subjects differently from uninfected referents. Advanced age and overweight/obesity were associated with increased mortality risk among infected men, while current smoking and alcohol use disorder were associated with lower mortality risk among infected men, when compared with those uninfected.

Characterizing chronological accumulation of comorbidities in healthy veterans: a computational approach.

Understanding patient accumulation of comorbidities can facilitate healthcare strategy and personalized preventative care. We applied a directed network graph to electronic health record (EHR) data and characterized comorbidities in a cohort of healthy veterans undergoing screening colonoscopy. The Veterans Affairs Cooperative Studies Program #380 was a prospective longitudinal study of screening and surveillance colonoscopy. We identified initial instances of three-digit ICD-9 diagnoses for participants with at least 5 years of linked EHR history (October 1999 to December 2015). For diagnoses affecting at least 10% of patients, we calculated pairwise chronological relative risk (RR). iGraph was used to produce directed graphs of comorbidities with RR > 1, as well as summary statistics, key diseases, and communities. A directed graph based on 2210 patients visualized longitudinal development of comorbidities. Top hub (preceding) diseases included ischemic heart disease, inflammatory and toxic neuropathy, and diabetes. Top authority (subsequent) diagnoses were acute kidney failure and hypertensive chronic kidney failure. Four communities of correlated comorbidities were identified. Close analysis of top hub and authority diagnoses demonstrated known relationships, correlated sequelae, and novel hypotheses. Directed network graphs portray chronologic comorbidity relationships. We identified relationships between comorbid diagnoses in this aging veteran cohort. This may direct healthcare prioritization and personalized care.

Development of a Multi-Study Repository to Support Research on Veteran Health: The VA Cooperative Studies Program Epidemiology Center-Durham (CSPEC-Durham) Data and Specimen Repository.

Federal agencies, including the Department of Veterans Affairs (VA), have prioritized improved access to scientific data and results collected through federally funded research. Our VA Cooperative Studies Program Epidemiology Center in Durham, North Carolina (CSPEC-Durham) assembled a repository of data and specimens collected through multiple studies on Veteran health issues to facilitate future research in these areas. We developed a single protocol, request process that includes scientific and ethical review of all applications, and a database architecture using metadata (common variable descriptors) to securely store and share data across diverse studies. In addition, we created a mechanism to allow data and specimens collected through older studies in which re-use was not addressed in the study protocol or consent forms to be shared if the future research is within the scope of the original consent. Our CSPEC-Durham Data and Specimen Repository currently includes research data, genomic data, and study specimens (e.g., DNA, blood) for three content areas: colorectal cancer, amyotrophic lateral sclerosis, and Gulf War research. The linking of the study specimens and research data can support additional genetic analyses and related research to improve Veterans' health.

The Interaction of Vitamin D and Corticosteroids: A Mortality Analysis of 26,508 Veterans Who Tested Positive for SARS-CoV-2.

This data-based cohort consisted of 26,508 (7%) United States veterans out of the 399,290 who tested positive for SARS-CoV-2 from 1 March to 10 September 2020. We aimed to assess the interaction of post-index vitamin D (Vit D) and corticosteroid (CRT) use on 30-day mortality among hospitalized and non-hospitalized patients with coronavirus disease 2019 (COVID-19). Combination Vit D and CRT drug use was assessed according to four multinomial pairs (-|+, -|-, +|+, +|-). Respective categorical effects were computed on a log-binomial scale as adjusted relative risk (aRR). Approximately 6% of veterans who tested positive for SARS-CoV-2 died within 30 days of their index date. Among hospitalized patients, a significantly decreased aRR was observed for the use of Vit D in the absence of CRTs relative to patients who received CRTs but not Vit D (aRR = 0.30; multiplicity corrected, p = 0.0004). Among patients receiving systemically administered CRTs (e.g., dexamethasone), the use of Vit D was associated with fewer deaths in hospitalized patients (aRR = 0.51) compared with non-hospitalized patients (aRR = 2.5) (P-for-Interaction = 0.0071). Evaluating the effect of modification of these compounds in the context of hospitalization may aid in the management of COVID-19 and provide a better understanding of the pathophysiological mechanisms underlying this and future infectious disease outbreaks.

Genetic Colorectal Cancer and Adenoma Risk Variants Are Associated with Increasing Cumulative Adenoma Counts.

BACKGROUND: The genetic basis for most individuals with high cumulative lifetime colonic adenomas is unknown. We investigated associations between known colorectal cancer-risk single-nucleotide polymorphisms (SNP) and increasing cumulative adenoma counts. METHODS: The Cooperative Studies Program #380 screening colonoscopy cohort includes 612 selected participants age 50 to 75 with genotyped blood samples and 10 years of clinical follow-up. We evaluated 41 published "colorectal cancer-risk SNPs" for associations with individual cumulative adenoma counts or having ≥10 cumulative adenomas. SNPs were analyzed singly or combined in a polygenic risk score (PRS). The PRS was constructed from eight published SNPs associated with multiple adenomas, termed "adenoma-risk SNPs." RESULTS: Four colorectal cancer-risk SNPs were associated with increasing cumulative adenoma counts (P < 0.05): rs12241008 (gene: VTI1A), rs2423279 (BMP2/HAO1), rs3184504 (SH2B3), and rs961253 (FERMT1/BMP2), with risk allele risk ratios of 1.31, 1.29, 1.24, and 1.23, respectively. Three colorectal cancer-risk SNPs were associated with ≥10 cumulative adenomas (P < 0.05), with risk allele odds ratios of 2.09 (rs3184504), 2.30 (rs961253), and 1.94 (rs3217901). A weighted PRS comprised of adenoma-risk SNPs was associated with higher cumulative adenomas (weighted rate ratio = 1.57; P = 0.03). CONCLUSIONS: In this mostly male veteran colorectal cancer screening cohort, several known colorectal cancer-risk SNPs were associated with increasing cumulative adenoma counts and the finding of ≥10 cumulative adenomas. In addition, an increasing burden of adenoma-risk SNPs, measured by a weighted PRS, was associated with higher cumulative adenomas. IMPACT: Future work will seek to validate these findings in different populations and then augment current colorectal cancer risk prediction tools with precancerous, adenoma genetic data.

High-Risk Adenomas at Screening Colonoscopy Remain Predictive of Future High-Risk Adenomas Despite an Intervening Negative Colonoscopy.

INTRODUCTION: Limited data inform the current postpolypectomy surveillance guidelines, which suggest a shortened interval to third colonoscopy after a negative second examination if high-risk adenomas (HRA) were present on the initial screening colonoscopy. Therefore, we examined the risk of HRA at third colonoscopy stratified by findings on 2 previous examinations in a prospective screening colonoscopy cohort of US veterans. METHODS: We identified participants who had 3 or more colonoscopies from CSP#380. We examined the risk of HRA on the third examination based on findings from the previous 2 examinations. Multivariate logistic regression was used to adjust for multiple covariates. RESULTS: HRA were found at the third examination in 114 (12.8%) of 891 participants. Those with HRA on both previous examinations had the greatest incidence of HRA at third examination (14/56, 25.0%). Compared with those with no adenomas on both previous examinations, participants with HRA on the first examination remained at significantly increased risk for HRA at the third examination at 3 years after a negative second examination (odds ratio [OR] 3.41, 95% confidence interval [CI] 1.28-9.08), 5 years (OR 3.14, 95% CI 1.49-6.61), and 7 years (OR 2.89, 95% CI 1.08-7.74). DISCUSSION: In a screening population, HRA on the first examination identified individuals who remained at increased risk for HRA at the third examination, even after a negative second examination. This finding supports current colorectal cancer surveillance guidelines, which suggest a shortened, 5-year time interval to third colonoscopy after a negative second examination if high-risk findings were present on the baseline examination.

Risk Factors for Early-Onset Colorectal Cancer.

BACKGROUND & AIMS: Colorectal cancer (CRC) incidence and mortality are increasing among persons younger than 50 years old in the United States, but risk factors associated with early-onset CRC (EOCRC) have not been widely studied. METHODS: We conducted a case-control study of US veterans 18 to 49 years old who underwent colonoscopy examinations from 1999 through 2014. EOCRC cases were identified from a national cancer registry; veterans who were free of CRC at their baseline colonoscopy through 3 years of follow-up were identified as controls. We collected data on age, sex, race/ethnicity, body weight, body mass index (BMI), diabetes, smoking status, and aspirin use. Multivariate-adjusted EOCRC odds were estimated for each factor, with corresponding 95% confidence interval (CI) values. RESULTS: Our final analysis included 651 EOCRC cases and 67,416 controls. Median age was 45.3 years, and 82.3% were male. Higher proportions of cases were older, male, current smokers, nonaspirin users, and had lower BMIs, compared with controls (P < .05). In adjusted analyses, increasing age and male sex were significantly associated with increased risk of EOCRC, whereas aspirin use and being overweight or obese (relative to normal BMI) were significantly associated with decreased odds of EOCRC. In post hoc analyses, weight loss of 5 kg or more within the 5-year period preceding colonoscopy was associated with higher odds of EOCRC (odds ratio 2.23; 95% CI 1.76-2.83). CONCLUSIONS: In a case-control study of veterans, we found increasing age and male sex to be significantly associated with increased risk of EOCRC, and aspirin use to be significantly associated with decreased risk; these factors also affect risk for CRC onset after age 50. Weight loss may be an early clinical sign of EOCRC. More intense efforts are required to identify the factors that cause EOCRC and signs that can be used to identify individuals at highest risk.

Survival Advantage With Adjuvant Chemotherapy for Locoregionally Advanced Rectal Cancer: A Veterans Health Administration Analysis.

BACKGROUND: Adjuvant chemotherapy (AC) after chemoradiation (CRT) and surgery for locoregionally advanced rectal cancer (LARC) is a standard of care in the United States. This study examined the role, optimal regimen, and duration of AC using data from the largest integrated health system in the United States. PATIENTS AND METHODS: Using the Veterans Affairs Central Cancer Registry, patients with stage II-III rectal cancer diagnosed in 2001 through 2011 who received neoadjuvant CRT and surgery with or without AC were identified. Kaplan-Meier analysis, log-rank tests, and propensity score (PS) adjustment analysis were used to assess survival. RESULTS: A total of 866 patients were identified; 417 received AC and 449 did not (observation [OBS] group). Median follow-up was 109 months. Median disease-specific survival (DSS) was not reached. Six-year DSS was 73.7%; 79.5% for the AC group versus 68.0% for the OBS group. PS-matched analysis for DSS favored AC (P=.0002). Median overall survival (OS) was 90.8 months. Six-year OS was 56.7%; 64.3% for AC versus 49.6% for OBS. In PS-matched analysis, median OS was 117.4 months for AC and 74.3 months for OBS (P<.0001). A DSS advantage was seen when comparing ≥4 months with <4 months of AC (P=.023). No difference in DSS or OS was seen with single-agent versus multiagent AC. CONCLUSIONS: In this population of patients with LARC treated with neoadjuvant CRT and surgery, OS and DSS were improved among those treated with AC versus OBS. DSS benefits were seen with ≥4 months of AC. No additional benefit was observed with multiagent therapy. In the absence of phase III data, these findings support the use of AC for LARC.

Baseline Colonoscopy Findings Associated With 10-Year Outcomes in a Screening Cohort Undergoing Colonoscopy Surveillance.

BACKGROUND & AIMS: Few studies have evaluated long-term outcomes of ongoing colonoscopic screening and surveillance in a screening population. We aimed to determine the 10-year risk for advanced neoplasia (defined as adenomas ≥10mm, adenomas with villous histology or high-grade dysplasia, or colorectal cancer [CRC]) and assessed whether baseline colonoscopy findings were associated with long-term outcomes. METHODS: We collected data from the Department of Veterans Affairs Cooperative Studies Program Study on 3121 asymptomatic veterans (50-75 years old) who underwent a screening colonoscopy from 1994 through 1997 at 13 medical centers and were then followed for 10 years or until death. We included 1915 subjects with at least 1 surveillance colonoscopy and estimated cumulative incidence of advanced neoplasia by Kaplan-Meier curves. We then fit a longitudinal joint model to estimate risk of advanced neoplasia at each subsequent examination after baseline, adjusting for multiple colonoscopies within individuals. RESULTS: Through 10 years of follow-up, there were 146 individuals among all baseline colonoscopy groups found to have at least 1 incident advanced neoplasia. The cumulative 10-year incidence of advanced neoplasia was highest among those with baseline CRC (43.7%; 95% CI 13.0%-74.4%), followed by those with baseline advanced adenoma (AA) (21.9%; 95% CI 15.7-28.1). The cumulative 10-year incidence of advanced neoplasia was 6.3% (95% CI 4.1%-8.5%) and 4.1% (95% CI 2.7%-5.4%) for baseline 1 to 2 small adenomas (<1cm, and without villous histology or high-grade dysplasia) and no neoplasia, respectively (log-rank P = .10). After adjusting for prior surveillance, the risk of advanced neoplasia at each subsequent examination was not significantly increased in veterans with 1 or 2 small adenomas at baseline (odds ratio 0.96; 95% CI 0.67-1.41) compared with veterans with no baseline neoplasia. CONCLUSIONS: Baseline screening colonoscopy findings associate with advanced neoplasia within 10 years. Individuals with only 1 or 2 small adenomas at baseline have a low risk of advanced neoplasia over 10 years. Alternative surveillance strategies, could be considered for these individuals.