Excess pancreatic cancer risk due to smoking and modifying effect of quitting smoking: The Multiethnic Cohort Study.

PURPOSE: Risk factors for pancreatic cancer include racial/ethnic disparities and smoking. However, risk trajectories by smoking history and race/ethnicity are unknown. We examined the association of smoking with pancreatic cancer by race/ethnicity to generate age-specific incidence estimates by smoking history. METHODS: We modeled pancreatic cancer incidence by race/ethnicity, age, pack-years, and years-quit using an excess relative risk model for 182,011 Multiethnic Cohort participants. We tested heterogeneity of smoking variables and pancreatic cancer by race/ethnicity and predicted incidence by smoking history. RESULTS: We identified 1,831 incident pancreatic cancer cases over an average 19.3 years of follow-up. Associations of pack-years (p interaction by race/ethnicity = 0.41) and years-quit (p interaction = 0.83) with pancreatic cancer did not differ by race/ethnicity. Fifty pack-years smoked was associated with 91% increased risk (95% CI 54%, 127%) relative to never smokers in the combined sample. Every year quit corresponded to 9% decreased excess risk (95% CI 2%, 15%) from pack-years smoked. Differences in baseline pancreatic cancer risk across racial/ethnic groups (p < 0.001) translated to large differences in risk for smokers at older ages across racial/ethnic groups (65-122 cases per 100,000 at age 70). CONCLUSION: Smoking pack-years were positively associated with elevated pancreatic cancer risk. Predicted risk trajectories showed a high impact of smoking cessation at < 65 years. Although we did not identify significant heterogeneity in the association of pack-years or years quit with pancreatic cancer risk, current smoker risk varied greatly by race/ethnicity in later life due to large differences in baseline risk.

Association of Obesity and Type 2 Diabetes with Non-Hodgkin Lymphoma: The Multiethnic Cohort.

BACKGROUND: Given the role of the immune system in non-Hodgkin lymphoma (NHL) etiology, obesity and type 2 diabetes (T2D) may impact NHL development. We examined the association of body mass index (BMI) and T2D with NHL in the multiethnic cohort (MEC). METHODS: The MEC recruited >215,000 participants in Hawaii and Los Angeles from five racial/ethnic groups; NHL cases were identified through cancer registry linkages. T2D status, and BMI at age 21 and cohort entry were derived from repeated self-reports; for T2D, Medicare claims were also applied. HRs and 95% confidence intervals (CI) for BMI and T2D as predictors of NHL were determined using Cox regression adjusted for relevant covariates. RESULTS: Among 192,424 participants, 3,472 (1.8%) with NHL and 68,850 (36%) with T2D after 19.2 ± 6.6 years follow-up, no significant association between T2D and NHL (HR, 1.04; 95% CI, 0.96-1.13) was observed. Stratification by BMI at cohort entry showed a significant association of T2D with NHL among individuals with normal weight only (HR, 1.18; 95% CI, 1.03-1.37). In a model with both BMI values plus T2D, only overweight (HR, 1.13; 95% CI, 1.01-1.26) and obesity (HR, 1.25; 95% CI, 0.99-1.59) at age 21 were associated with NHL incidence. Stratification by sex, race/ethnicity, and NHL subtype indicated no differences. CONCLUSIONS: Our findings suggest an association between T2D and NHL incidence in several subgroups but not in the total population and an elevated risk related to early-life BMI. IMPACT: Excess body weight in early life, rather than T2D, may be a predictor of NHL incidence.

Risk Factors for Type 2 Diabetes in the Multiethnic Cohort.

OBJECTIVES: In this report, we investigated the association between established risk factors and type 2 diabetes (T2D) across 5 distinct ethnic groups and explored differences according to T2D definition within the Multiethnic Cohort (MEC) Study. METHODS: Using the full MEC, with participants in Hawaii and Los Angeles (N=172,230), we applied Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All participants completed questionnaires asking about demographics, anthropometrics, lifestyle factors, and regular diet. T2D status was determined from self-reported diagnosis/medication and Medicare claims. We assessed the associations between well-established risk factors and T2D in the full cohort, after stratification by ethnic group, according to the T2D definition, and in a biorepository subset. Effect modification by ethnicity was evaluated using Wald's tests. RESULTS: Overall, 46,500 (27%) participants had an incident T2D diagnosis after a mean follow-up of 17.1±6.9 years. All predictors were significantly associated with T2D: overweight (HR=1.74), obesity (HR=2.90), red meat intake (HR=1.15), short (HR=1.04) and long (HR=1.08) sleep duration, and smoking (HR=1.26) predicted a significantly higher T2D incidence, whereas coffee (HR=0.90) and alcohol (HR=0.78) consumption, physical activity (HR=0.89), and diet quality (HR=0.96) were associated with lower T2D incidence. The strength of these associations was similar across ethnic groups with noteworthy disparities for overweight/obesity, physical activity, alcohol intake, coffee consumption, and diet quality. CONCLUSIONS: These findings confirm the importance of known risk factors for T2D across ethnic groups, but small differences were detected that may contribute to disparate incidence rates in some ethnic groups, especially for obesity and physical activity.

Interethnic Differences in Bladder Cancer Incidence and the Association between Type 2 Diabetes and Bladder Cancer in the Multiethnic Cohort Study.

Background: Research on the association between type 2 diabetes (T2D) and bladder cancer (BCA) risk among non-European ancestry populations is sparse to nonexistent, and most prior studies rely on a single baseline assessment of T2D status. Methods: We estimated the T2D-BCA association using the Multiethnic Cohort Study of 185,059 men and women in California and Hawaii. Participants were African American, European American, Japanese American, Latin American, and Native Hawaiian, ages 45-75 years at enrollment (1993-1996). T2D was assessed by self-report at baseline, follow-up surveys, and Medicare claims. Cases were identified using Surveillance, Epidemiology and End Results Program cancer registries through 2016. Associations were estimated by race/ethnicity using Cox proportional hazards regression. Adjusted attributable fractions (AAF) and cumulative absolute risk of bladder cancer were estimated across groups. Results: Over an average 19.7 years of follow-up 1,890 incident bladder cancer cases were diagnosed. Time-varying T2D was associated with bladder cancer in the multiethnic sample (HR = 1.17; 95% confidence interval, 1.05-1.30); however, the HR did not differ by race/ethnicity (P = 0.85). The AAF was 4.2% in the multiethnic sample and largest among Native Hawaiians (9.8%). Absolute risk of bladder cancer among European Americans without T2D was higher than all other groups with T2D. Conclusion: T2D is significantly associated with bladder cancer risk in a multiethnic sample. Significance: Those with T2D have higher incidence of bladder cancer, regardless of racial/ethnic group. Reducing T2D prevalence could substantially lower bladder cancer incidence among Native Hawaiians due to T2D being more common in this group. High absolute risk of bladder cancer among European Americans, regardless of T2D status, indicates that elevated bladder cancer risk in this group may be due to factors other than T2D. Future studies must explore reasons for this difference in incidence.

The association between ambient air pollutants and pancreatic cancer in the Multiethnic Cohort Study.

BACKGROUND: Prior studies examining the association between ambient air pollutants and pancreatic cancer have been conducted in racially/ethnically homogeneous samples and have produced mixed results, with some studies supporting evidence of an association with fine particulate matter. METHODS: To further investigate these findings, we estimated exposure levels of particulate matter (PM2.5, PM10) and oxides of nitrogen (NOX, and NO2) using kriging interpolation for 100,527 men and women from the Multiethnic Cohort Study, residing largely in Los Angeles County from 1993 through 2013. We measured the association between these air pollutants and incident pancreatic cancer using Cox proportional hazards models with time-varying pollutant measures, with adjustment for confounding factors. RESULTS: A total of 821 incident pancreatic cancer and 1,660,488 person-years accumulated over the study period, with an average follow-up time of over 16 years. PM2.5 (per 10 µg/m3) was associated with incident pancreatic cancer (hazard ratio [HR] = 1.61; 95% CI, 1.09, 2.37). This PM2.5 -association was strongest among Latinos (HR = 3.59; 95% CI, 1.60, 8.06) and ever smokers (HR = 1.76; 95% CI, 1.05, 2.94). There was no association for PM10 (HR = 1.12; 95% CI, 0.94, 1.32, per 10 µg/m3), NOx (HR = 1.14; 95% CI, 0.88, 1.48, per 50 ppb), or NO2 (HR = 1.14; 95% CI, 0.85, 1.54, per 20 ppb). CONCLUSIONS: Our findings support prior research identifying an association between fine particulate matter, PM2.5, and pancreatic cancer. Although not statistically heterogeneous, this association was most notable among Latinos and smokers. Future studies are needed to replicate these results in an urban setting and in a racially/ethnically diverse population.

Red meat consumption, cooking mutagens, NAT1/2 genotypes and pancreatic cancer risk in two ethnically diverse prospective cohorts.

There is limited evidence on the association between red meat consumption and pancreatic cancer among ethnic minorities. We assessed this relationship in two large prospective cohorts: the Multiethnic Cohort Study (MEC) and the Southern Community Cohort Study (SCCS). Demographic, dietary and other risk factor data were collected at cohort entry. Red meat intake was assessed using cohort-specific validated food frequency questionnaires. Incident pancreatic cancer cases were identified via linkages to state cancer registries. Cox regression was used to calculate relative risks (RRs) and 95% confidence intervals (CIs) for the association of red meat intake with pancreatic cancer risk in each cohort. We performed additional analyses to evaluate cooking methods, mutagens and effect modification by NAT1/2 genotypes. From a total of 184 542 (MEC) and 66 793 (SCCS) at-risk participants, we identified 1618 (MEC) and 266 (SCCS) incident pancreatic cancer cases. Red meat consumption was associated with pancreatic cancer risk in the MEC (RRQ4vsQ1 1.18, 95% CI 1.02-1.37) and with borderline statistical significance in the SCCS (RRQ4vsQ1 1.31, 95% CI 0.93-1.86). This association was significant in African Americans (RRQ4vsQ1 1.49, 95% CI 1.06-2.11) and Latinos (RRQ4vsQ1 1.44, 95% CI 1.02-2.04) in the MEC, and among African Americans (RRQ4vsQ1 1.55, 95% CI 1.03-2.33) in the SCCS. NAT2 genotypes appeared to modify the relationship between red meat and pancreatic cancer in the MEC (pinteraction = 0.03). Our findings suggest that the associations for red meat may be strongest in African Americans and Latinos. The mechanisms underlying the increased risk for these populations should be further investigated.

Replication and Genetic Risk Score Analysis for Pancreatic Cancer in a Diverse Multiethnic Population.

BACKGROUND: Genome-wide association studies (GWAS) have identified several SNPs associated with pancreatic cancer. No studies yet have attempted to replicate these SNPs in US minority populations. We aimed to replicate the associations of 31 GWAS-identified SNPs with pancreatic cancer and build and test a polygenic risk score (PRS) for pancreatic cancer in an ethnically diverse population. METHODS: We evaluated 31 risk variants in the Multiethnic Cohort and the Southern Community Cohort Study. We included 691 pancreatic ductal adenocarcinoma (PDAC) cases and 13,778 controls from African-American, Japanese-American, Latino, Native Hawaiian, and white participants. We tested the association between each SNP and PDAC, established a PRS using the 31 SNPs, and tested the association between the score and PDAC risk. RESULTS: Eleven of the 31 SNPs were replicated in the multiethnic sample. The PRS was associated with PDAC risk [OR top vs. middle quintile = 2.25 (95% confidence interval, 1.73-2.92)]. Notably, the PRS was associated with PDAC risk in all ethnic groups except Native Hawaiian (OR per risk allele ranged from 1.33 in Native Hawaiians to 1.91 in African Americans; P heterogeneity = 0.12). CONCLUSIONS: This is the first study to replicate 11 of the 31 GWAS-identified risk variants for pancreatic cancer in multiethnic populations, including African Americans, Japanese Americans, and Latinos. Our results also suggest a potential utility of PRS with GWAS-identified risk variants for the identification of individuals at increased risk for PDAC across multiple ethnic groups. IMPACT: PRS can potentially be used to stratify pancreatic cancer risk across multiple ethnic groups.

A Systematic Review of the Efficacy of Preclinical Models of Lung Cancer Drugs.

Background: Preclinical cell models are the mainstay in the early stages of drug development. We sought to explore the preclinical data that differentiated successful from failed therapeutic agents in lung cancer. Methods: One hundred thirty-four failed lung cancer drugs and twenty seven successful lung cancer drugs were identified. Preclinical data were evaluated. The independent variable for cell model experiments was the half maximal inhibitory concentration (IC50), and for murine model experiments was tumor growth inhibition (TGI). A logistic regression was performed on quartiles (Q) of IC50s and TGIs. Results: We compared odds of approval among drugs defined by IC50 and TGI quartile. Compared to drugs with preclinical cell experiments in highest IC50 quartile (Q4, IC50 345.01-100,000 nM), those in Q3 differed little, but those in the lower two quartiles had better odds of being approved. However, there was no significant monotonic trend identified (P-trend 0.4). For preclinical murine models, TGI values ranged from -0.3119 to 1.0000, with a tendency for approved drugs to demonstrate poorer inhibition than failed drugs. Analyses comparing success of drugs according to TGI quartile produced interval estimates too wide to be statistically meaningful, although all point estimates accord with drugs in Q2-Q4 (TGI 0.5576-0.7600, 0.7601-0.9364, 0.9365-1.0000) having lower odds of success than those in Q1 (-0.3119-0.5575). Conclusion: There does not appear to be a significant linear trend between preclinical success and drug approval, and therefore published preclinical data does not predict success of therapeutics in lung cancer. Newer models with predictive power would be beneficial to drug development efforts.

Incident testicular cancer in relation to using marijuana and smoking tobacco: A systematic review and meta-analysis of epidemiologic studies.

BACKGROUND: Recent epidemiologic studies identified credible associations between marijuana smoking and risk of nonseminomatous testicular germ cell tumors (TGCTs), but did not distinguish exposure to cannabinoid compounds from exposure to other constituents of smoke. METHODS: We implemented a systematic review of scholarly literature followed by random effects meta-analysis to quantitatively synthesize published data relating incident TGCT to each of 2 exposure histories: ever using marijuana, and ever smoking tobacco. RESULTS: We identified four epidemiologic studies of marijuana use and 12 of tobacco smoking. Summary data concur with earlier reports of a specific association of marijuana use with nonseminoma, summary odds ratio [sOR] = 1.71 (95% confidence interval [CI] 1.12-2.60), and identify a positive association, sOR = 1.18 (95% CI 1.05-1.33), between tobacco smoking and all TGCT. CONCLUSIONS: Available data accord with positive associations between incident TGCT and each exposure, implicating both cannabinoid compounds and other constituents of smoke. Etiologic interpretation awaits epidemiologic studies that assess associations between tobacco smoking and nonseminomatous TGCT, investigating not only these exposures but also both co-use of tobacco and marijuana and smoke-free sources of cannabinoids, while adequately evaluating potential confounding among all of these exposures.

High-Quality Diets Are Associated With Reduced Risk of Hepatocellular Carcinoma and Chronic Liver Disease: The Multiethnic Cohort.

Hepatocellular carcinoma (HCC) and chronic liver disease (CLD) are major sources of morbidity and mortality globally. Both HCC incidence and CLD mortality are known to vary by race. There is limited research on the association between dietary measures and these outcomes in a diverse population. We prospectively investigated the associations between four diet quality index (DQI) scores (Healthy Eating Index-2010, Alternative Healthy Eating Index-2010, Alternate Mediterranean Diet [aMED], and Dietary Approaches to Stop Hypertension), HCC incidence, and CLD mortality in the Multiethnic Cohort. We analyzed data from 169,806 African Americans, Native Hawaiians, Japanese Americans, Latinos, and whites, aged 45 to 75 years. DQI scores were calculated by using a validated food frequency questionnaire administered at baseline. During an average 17 years of follow-up, 603 incident cases of HCC and 753 CLD deaths were identified among study participants. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for each DQI were estimated using Cox regression. Higher aMED scores, reflecting favorable adherence to a healthful diet, were associated with a lower risk of HCC (quintile [Q]5 versus Q1 HR, 0.68; 95% CI, 0.51-0.90; trend, P = 0.02). In racial/ethnic-specific analyses, there was no significant heterogeneity across groups (interaction, P = 0.32); however, the association only remained statistically significant among Latinos (Q4 versus Q1 HR, 0.47; 95% CI, 0.29-0.79; trend, P = 0.006). All DQI measures were inversely associated with CLD mortality, with no significant heterogeneity by race/ethnicity. Conclusion: Higher aMED scores were associated with a lower risk of HCC. A higher score of any DQI was associated with a lower risk of CLD mortality. These results suggest that better diet quality may reduce HCC incidence and CLD mortality.

A proteomics approach for the identification of species-specific immunogenic proteins in the Mycobacterium abscessus complex.

The Mycobacterium abscessus complex can cause fatal pulmonary disease, especially in cystic fibrosis patients. Diagnosing M. abscessus complex pulmonary disease is challenging. Immunologic assays specific for M. abscessus are not available. In this study seven clinical M. abscessus complex strains and the M. abscessus reference strain ATCC19977 were used to find species-specific proteins for their use in immune assays. Six strains showed rough and smooth colony morphotypes simultaneously, two strains only showed rough mophotypes, resulting in 14 separate isolates. Clinical isolates were submitted to whole genome sequencing. Proteomic analysis was performed on bacterial lysates and culture supernatant of all 14 isolates. Species-specificity for M. abscessus complex was determined by a BLAST search for proteins present in all supernatants. Species-specific proteins underwent in silico B- and T-cell epitope prediction. All clinical strains were found to be M. abscessus ssp. abscessus. Mutations in MAB_4099c as a likely genetic basis of the rough morphotype were found in six out of seven clinical isolates. 79 proteins were present in every supernatant, of which 12 are exclusively encoded by all members of M. abscessus complex plus Mycobacterium immunogenum. In silico analyses predicted B- and T-cell epitopes in all of these 12 species-specific proteins.

Prevalence of nonaccidental trauma among children at American College of Surgeons-verified pediatric trauma centers.

BACKGROUND: Child abuse remains a national epidemic that has detrimental effects if unnoticed in the clinical setting. Extreme cases of child abuse, or nonaccidental trauma (NAT), have large financial burdens associated with them due to treatment costs and long-term effects of abuse. Clinicians who have additional training and experience with pediatric trauma are better equipped to detect signs of NAT and have more experience reporting it. This additional training and experience can be measured by using the American College of Surgeons (ACS) Pediatric Trauma verification. It is hypothesized that ACS-verified pediatric trauma centers (vPTCs) have an increased prevalence of NAT because of this additional experience and training relative to non-ACS vPTCs. METHODS: The National Trauma Data Bank, for the years 2007 to 2014, was utilized to compare the prevalence of NAT between ACS vPTCs relative to non-ACS vPTCs to produce both crude and Injury Severity Score adjusted prevalence ratio estimates. RESULTS: The majority of NAT cases across all hospitals were male (58.3%). The mean age of the NAT cases was 2.3 years with a mean Injury Severity Score (ISS) of 11.1. The most common payment method was Medicaid (64.4%). The prevalence of NAT was 1.82 (1.74-1.90) times higher among ACS vPTCs and 1.81 (1.73-1.90) after adjusting for ISS. CONCLUSIONS: The greater prevalence of NAT at vPTCs likely represents a more accurate measure of NAT among pediatric trauma patients, likely due to more experience and training of clinicians. LEVEL OF EVIDENCE: Prognostic/Epidemiological, Level II.