Helicobacter hepaticus and Helicobacter bilis in liver and biliary cancers from ATBC and PLCO.

BACKGROUND: Helicobacter species (spp.) have been detected in human bile and hepatobiliary tissue Helicobacter spp. promote gallstone formation and hepatobiliary tumors in laboratory studies, though it remains unclear whether Helicobacter spp. contribute to these cancers in humans. We used a multiplex panel to assess whether seropositivity to Helicobacter (H.) hepaticus or H. bilis proteins was associated with the development of hepatobiliary cancers in the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, and US-based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). METHODS: We included 62 biliary and 121 liver cancers, and 190 age-matched controls from ATBC and 74 biliary and 105 liver cancers, and 364 age- and sex-matched controls from PLCO. Seropositivity to 14 H. hepaticus and H. bilis antigens was measured using a multiplex assay. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for major hepatobiliary cancer risk factors and Helicobacter pylori serostatus. RESULTS: Seropositivity to the H. bilis antigen, P167D, was associated with more than a twofold higher risk of liver cancer (OR: 2.38; 95% CI: 1.06, 5.36) and seropositivity to the H. hepaticus antigens HH0407 or HH1201, or H. bilis antigen, HRAG 01470 were associated with higher risk of biliary cancer (OR: 5.01; 95% CI: 1.53, 16.40; OR: 2.40; 95% CI: 1.00, 5.76; OR: 3.27; 95% CI: 1.14, 9.34, respectively) within PLCO. No associations for any of the H. hepaticus or H. bilis antigens were noted for liver or biliary cancers within ATBC. CONCLUSIONS: Further investigations in cohort studies should examine the role of Helicobacter spp. in the etiology of liver and biliary cancers.

Circulating hormones and risk of gastric cancer by subsite in three cohort studies.

BACKGROUND: Obesity has been positively associated with gastric cancer. Excess fat impacts hormones, which have been implicated in carcinogenesis. We investigated obesity-related hormones and cardia gastric cancer (CGC) and non-cardia gastric cancer (NCGC) risk. METHODS: Nested case-control studies were conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort (61 CGCs, and 172 NCGCs and matched controls) and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study (100 CGCs and 65 NCGCs and matched controls); serum hormones were measured. In UK-Biobank (n = 458,713), we included 137 CGCs and 92 NCGCs. Sex-specific analyses were conducted. For EPIC and ATBC, odds ratios (ORs), and for UK-Biobank hazard ratios (HRs), were estimated using conditional logistic regression and Cox regression, respectively. RESULTS: Insulin-like growth-factor-1 was positively associated with CGC and NCGC in EPIC men (ORper 1-SD increase 1.94, 95% CI 1.03-3.63; ORper 1-SD increase 1.63, 95% CI 1.05-2.53, respectively), with similar findings for CGC in UK-Biobank women (HRper 1-SD increase 1.76, 95% CI 1.08-2.88). Leptin in EPIC men and C-peptide in EPIC women were positively associated with NCGC (ORT3 vs. T1 2.72, 95% CI 1.01-7.34 and ORper 1-SD increase 2.17, 95% CI 1.19-3.97, respectively). Sex hormone-binding globulin was positively associated with CGC in UK-Biobank men (HRper 1-SD increase 1.29, 95% CI 1.02-1.64). Conversely, ghrelin was inversely associated with NCGC among EPIC and ATBC men (ORper 1-SD increase 0.53, 95% CI 0.34-0.84; ORper 1-SD increase 0.22, 95% CI 0.10-0.50, respectively). In addition, dehydroepiandrosterone was inversely associated with CGC in EPIC and ATBC men combined. CONCLUSIONS: Some obesity-related hormones influence CGC and NCGC risk.

The U-shaped association between body mass index and gastric cancer risk in the Helicobacter pylori Biomarker Cohort Consortium: A nested case-control study from eight East Asian cohort studies.

The association between body mass index (BMI) and noncardia gastric cancer (NCGC) risk remains controversial. The purpose of our study was to examine the association of BMI with NCGC risk with consideration of Helicobacter pylori (HP) biomarkers. This international nested case-control study, composed of 1,591 incident NCGC cases and 1,953 matched controls, was established from eight cohorts in China, Japan and Korea, where the majority of NCGCs are diagnosed worldwide. HP antibody biomarkers were measured in blood collected at cohort enrollment by multiplex serology. The NCGC risk according to baseline BMI was estimated using logistic regression to produce odds ratios (ORs) and 95% confidence intervals (CIs). We found a U-shaped association between BMI category and NCGC risk. Compared to those with reference BMI (22.6-25.0 kg/m2 ), those with lower and higher BMI had an increased NCGC risk (BMI <18.5 kg/m2 , OR = 1.56, 95% CI = 1.04-2.34; BMI >27.5 kg/m2 , OR = 1.48, 95% CI = 1.15-1.91; adjusted for age, sex and smoking). The U-shaped association was persistent among subjects with HP infection and high-risk biomarkers (HP+ CagA+: BMI <18.5 kg/m2 , OR = 1.60, 95% CI = 1.00-2.55; BMI >27.5 kg/m2 , OR = 1.59, 95% CI = 1.21-2.11; and Omp+ HP0305+: BMI <18.5 kg/m2 , OR = 1.88, 95% CI = 1.04-3.42; BMI >27.5 kg/m2 , OR = 1.70, 95% CI = 1.20-2.42, respectively). Our study provides evidence of significantly increased NCGC risk among individuals with low or high BMI, including in subjects with high-risk HP biomarkers (HP+ CagA+, Omp+ HP0305+) in the high-risk area of East Asia.

Serum ghrelin and esophageal and gastric cancer in two cohorts in China.

Ghrelin is a hormone produced in the oxyntic glands of the stomach. Previous work by our group has suggested that serum ghrelin concentrations are inversely associated with gastric and esophageal cancer risk. We measured ghrelin concentrations in the Linxian General Population Nutrition Intervention Trial (NIT), and the Shanghai Women's Health Study (SWHS). In NIT, we analyzed serum samples from 298 esophageal squamous cell carcinoma (ESCC) cases, 518 gastric cardia adenocarcinoma (GCA) cases, 258 gastric noncardia adenocarcinoma (GNCA) cases and 770 subcohort controls (case-cohort). In SWHS, we measured ghrelin in plasma samples from 249 GNCA cases and 498 matched controls (nested case-control). Ghrelin was measured using radioimmunoassay. In NIT and SWHS, low ghrelin concentrations were associated with an increased risk of developing GNCA and GCA. The hazard ratio (HR Q1:Q4 ) for GNCA in NIT was 1.35 (95% CI: 0.89-2.05; p-trend = 0.02); the odds ratio in SWHS was 1.66 (95% CI: 1.02-2.70; p-trend = 0.06). Low ghrelin was associated with a twofold increase of GCA (HR Q1:Q4 = 2.00, 95% CI: 1.45-2.77; p-trend<0.001). In contrast, a lower risk of ESCC (NIT ESCC HR Q1:Q4 = 0.65, 95% CI: 0.45-0.92; p-trend = 0.02) was found in NIT. Low baseline ghrelin concentrations were associated with an increased risk for GNCA and GCA in the NIT and the SWHS. In contrast, low ghrelin concentrations at baseline were associated with a reduced risk of developing ESCC in the NIT. Ghrelin may be an early marker of future cancer risk for developing upper gastrointestinal cancer in regions of high incidence.

Seropositivity for Helicobacter pylori and hepatobiliary cancers in the PLCO study.

Helicobacter has been suggested to play a possible role in hepatitis, gallstones, and hepatobiliary tumours. We assessed whether seropositivity to 15 H. pylori proteins was associated with subsequent incidence of 74 biliary tract and 105 liver cancer cases vs. 357 matched controls in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). Odds ratios and 95% confidence intervals were computed by conditional logistic regression after adjustment for known hepatobiliary cancer risk factors. H. pylori seropositivity was not associated with either biliary tract (1.76, 0.90-3.46) or liver cancer (0.87, 0.46-1.65). CagA seropositivity was associated with both endpoints, although the latter association was not statistically significant (biliary tract: 2.16, 1.03-4.50; liver cancer: 1.96, 0.98-3.93) and neither association was statistically significant after correcting for multiple comparisons. Together, these results suggest possible associations between H. pylori and hepatobiliary cancer and suggest the value of future studies investigating the association.Trial registration number: NCT00339495.

The application of six dietary scores to a Middle Eastern population: a comparative analysis of mortality in a prospective study.

Background The associations between dietary indices and mortality have not been evaluated in populations from the Middle East, which have different dietary patterns compared to the US and Europe. In this study, we evaluated the association between six dietary indices and mortality in the Golestan Cohort Study (GCS) in Iran, which is the largest prospective study in the Middle East with 50,045 participants. Methods The six dietary indices, namely the Healthy Eating Index (HEI-2015), Alternative Healthy Eating Index (AHEI-2010), Alternative Mediterranean Diet (AMED), Dietary Approach to Stop Hypertension created by Fung (DASH-Fung) and Mellen (DASH-Mellen), and the World Cancer Research Fund (WCRF/AICR) index, were applied to data from a food frequency questionnaire, computed and divided into quintiles. Adjusted Cox models were used to estimate hazards ratio (HR) and 95% confidence intervals (CI) for overall and cause-specific mortality, using the lowest quintile as a reference group. Results Among 42,373 participants included in the current analyses, 4424 subjects died during 10.6 years of follow-up. Participants with the highest quintile dietary scores, compared with the lowest quintile dietary scores, had significantly decreased overall mortality in the AHEI-2010, AMED, DASH-Fung, and WCRF/AICR indices (HR 0.88, 95% CI = 0.80-0.97; 0.80, 0.70-0.91; 0.77, 0.70-0.86; and 0.79, 0.70-0.90, respectively). A reduced cardiovascular mortality was found for high AHEI-2010 and DASH-Fung scores (17% and 23%, respectively), and a reduced cancer mortality for high HEI-2015, AMED, and DASH-Fung scores (21, 37 and 25%, respectively). Conclusion Various indices of dietary quality are inversely associated with overall mortality, and selectively with cancer and cardiovascular mortality in the GCS, which contribute to the generalizability and validity of dietary guidelines.

Serum ghrelin is associated with risk of colorectal adenocarcinomas in the ATBC study.

BACKGROUND: Colorectal cancers are the third most common cancers in women and men in the USA. While dietary and lifestyle factors such as Western diet, physical inactivity and obesity have been linked to an increased risk of this malignancy, the mechanisms for these associations are unclear. GI hormones, including ghrelin, are involved in energy balance by mediating appetite and metabolism; however, the association between ghrelin and colorectal cancer has not been studied. METHODS: We conducted a case-control study nested within the all-male Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study of Finnish smokers (aged 50-69 years) to examine serum ghrelin concentration and colorectal cancer risk. Data from 284 colon and 239 rectal cancers and 523 controls (matched on age, date of blood draw and serum availability) were analysed. ORs and 95% CIs were calculated using multivariable (conditional) logistic regression. RESULTS: Overall, low-serum ghrelin was significantly associated with increased risk of colorectal cancer (Q1 vs Q4: OR:1.57, 95% CI 1.05 to 2.34). For individuals developing tumours within 10 years of blood draw, those in the lowest quartile of serum ghrelin concentrations were statistically significantly more likely to develop colorectal cancers than those with higher serum ghrelin concentrations (OR: 10.86, 95% CI 5.01 to 23.55). However, for individuals with tumours developing more than 20 years after blood draw, low-serum ghrelin concentrations were associated with a decreased risk of colorectal cancer relative to those with the highest serum ghrelin concentrations (OR: 0.26, 95% CI 0.11 to 0.64). CONCLUSION: Low-serum ghrelin was associated with an increased colorectal cancer risk within 10 years of blood draw with a decreased risk for developing colorectal cancer more than 20 years after blood draw. These results suggest that ghrelin concentrations may vary across the carcinogenic process.

Nut consumption and the risk of oesophageal squamous cell carcinoma in the Golestan Cohort Study.

BACKGROUND: Nut consumption has been inversely associated with gastric cancer incidence in US-based studies, but not with oesophageal cancer. However, there is aetiologic heterogeneity, among oesophageal squamous cell carcinoma (ESCC) cases in low-risk vs. high-risk populations. The objective of this study was to evaluate the association between nut consumption and risk of ESCC in a high-risk population. METHODS: The Golestan Cohort Study enroled 50,045 participants in Northeastern Iran, between 2004 and 2008. Intake of peanuts, walnuts and mixed nuts (including seeds) were assessed using a validated food frequency questionnaire at baseline. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals for subsequent ESCC adjusted for potential confounders. Non-consumers of nuts were used as the reference category and the consumers were categorised into tertiles. RESULTS: We accrued 280 incident ESCC cases during 337,983 person-years of follow up. Individuals in the highest tertiles of total nut consumption, and mixed nut consumption were significantly associated with lower risk of developing ESCC compared to non-consumers (HR = 0.60, 95% CI = 0.39-0.93, p-trend = 0.02, and HR = 0.52, 95% CI = 0.32-0.84, p trend = 0.002, respectively). CONCLUSIONS: We found a statistically significant inverse association between total nut consumption and the risk of ESCC in this high-risk population.

Family history of colorectal cancer in first-degree relatives and metachronous colorectal adenoma.

OBJECTIVES: Little is known about the relationship between having a first-degree relative (FDR) with colorectal cancer (CRC) and risk for metachronous colorectal adenoma (CRA) following polypectomy. METHODS: We pooled data from seven prospective studies of 7697 patients with previously resected CRAs to quantify the relationship between having a FDR with CRC and risk for metachronous adenoma. RESULTS: Compared with having no family history of CRC, a positive family history in any FDR was significantly associated with increased odds of developing any metachronous CRA (OR = 1.14; 95% CI = 1.01-1.29). Higher odds of CRA were observed among individuals with an affected mother (OR = 1.27; 95% CI = 1.05-1.53) or sibling (OR = 1.34; 95% CI = 1.11-1.62) as compared with those without, whereas no association was shown for individuals with an affected father. Odds of having a metachronous CRA increased with number of affected FDRs, with ORs (95% CIs) of 1.07 (0.93-1.23) for one relative and 1.39 (1.02-1.91) for two or more. Younger age of diagnosis of a sibling was associated with higher odds of metachronous CRA, with ORs (95% CIs) of 1.66 (1.08-2.56) for diagnosis at <54 years; 1.34 (0.89-2.03) for 55-64 years; and 1.10 (0.70-1.72) for >65 years (p-trend = 0.008). Although limited by sample size, results for advanced metachronous CRA were similar to those for any metachronous CRA. CONCLUSIONS: A family history of CRC is related to a modestly increased odds of metachronous CRA. Future research should explore whether having a FDR with CRC, particularly at a young age, should have a role in risk stratification for surveillance colonoscopy.

Epstein-Barr Virus Antibody Titers Are Not Associated with Gastric Cancer Risk in East Asia.

BACKGROUND: Epstein-Barr virus (EBV)-positive gastric cancers represent a distinct subtype of gastric cancers and account for nearly 10% of the gastric cancer burden, yet risk detection strategies for this cancer subtype are lacking. METHODS: We conducted a nested case-control study where we assayed 4 EBV antigens [viral capsid antigen (VCA), early antigen (EA), Epstein-Barr nuclear antigen (EBNA), and BZLF1-encoded replication activator protein (ZEBRA)] in either sera or plasma from 1447 gastric cancer cases and 1797 controls obtained from seven prospective cohorts representing individuals from the high gastric cancer-risk countries of China, Japan, and Korea. RESULTS: The prevalence of EBV sero-positivity was universal with the exception of one sero-negative individual, and the highest titers of the EBV antigens VCA (OR 0.95, 95% CI 0.78-1.17), EBNA (OR 0.88, 95% CI 0.72-1.08), EA (OR 0.97, 95% CI 0.79-1.19), and ZEBRA (OR 0.87, 95% CI 0.71-1.07) were not associated with risk of incident gastric cancer. When we stratified these data by H. pylori status, there was no change in the association. CONCLUSIONS: Multiplex serology of the aforementioned EBV antigens in serum may not be a suitable biomarker for predicting gastric cancer risk in East Asian populations.

Risk stratification of individuals with low-risk colorectal adenomas using clinical characteristics: a pooled analysis.

OBJECTIVE: For individuals with 1-2 small (<1 cm) low-risk colorectal adenomas, international guidelines range from no surveillance to offering surveillance colonoscopy in 5-10 years. We hypothesised that the risks for metachronous advanced neoplasia (AN) among patients with low-risk adenomas differ based on clinical factors distinct from those currently used. DESIGN: We pooled data from seven prospective studies to assess the risk of metachronous AN. Two groups with 1-2 small adenomas were defined based on guidelines from the UK (n=4516) or the European Union (EU)/US (n=2477). RESULTS: Absolute risk of metachronous AN ranged from a low of 2.9% to a high of 12.2%, depending on specific risk factor and guideline used. For the UK group, the highest absolute risks for metachronous AN were found among individuals with a history of prior polyp (12.2%), villous histology (12.2%), age ≥70 years (10.9%), high-grade dysplasia (10.9%), any proximal adenoma (10.2%), distal and proximal adenoma (10.8%) or two adenomas (10.1%). For the EU/US group, the highest absolute risks for metachronous AN were among individuals with a history of prior polyp (11.5%) or the presence of both proximal and distal adenomas (11.0%). In multivariate analyses, strong associations for increasing age and history of prior polyps and odds of metachronous AN were observed, whereas more modest associations were shown for baseline proximal adenomas and those with villous features. CONCLUSIONS: Risks of metachronous AN among individuals with 1-2 small adenomas vary according to readily available clinical characteristics. These characteristics may be considered for recommending colonoscopy surveillance and require further investigation.

Low vitamin B12 increases risk of gastric cancer: A prospective study of one-carbon metabolism nutrients and risk of upper gastrointestinal tract cancer.

Previous studies have found associations between one-carbon metabolism nutrients and risk of several cancers, but little is known regarding upper gastrointestinal tract (UGI) cancer. We analyzed prediagnostic serum concentrations of several one-carbon metabolism nutrients (vitamin B12, folate, vitamin B6, riboflavin and homocysteine) in a nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study of male smokers, which was undertaken in Finland between 1985 and 1988. We conducted a nested case-control study including 127 noncardia gastric adenocarcinoma (NCGA), 41 esophagogastric junctional adenocarcinoma and 60 esophageal squamous cell carcinoma incident cases identified within ATBC. Controls were matched to cases on age, date of serum collection and follow-up time. One-carbon nutrient concentrations were measured in fasting serum samples collected at baseline (up to 17 years prior to cancer diagnosis). Odds ratios and 95% confidence intervals (CI) were calculated using conditional logistic regression. Lower prediagnostic vitamin B12 concentrations at baseline were associated with a 5.8-fold increased risk of NCGA (95% CI = 2.7-12.6 for lowest compared to highest quartile, p-trend <0.001). This association remained in participants who developed cancer more than 10 years after blood collection, and after restricting the analysis to participants with clinically normal serum vitamin B12 (>300 pmol/L). In contrast, pepsinogen I, a known serologic marker of gastric atrophy, was not associated with NCGA in this population. As vitamin B12 absorption requires intact gastric mucosa to produce acid and intrinsic factor, our findings suggest vitamin B12 as a possible serologic marker for the atrophic gastritis that precedes NCGA, one more strongly associated with subsequent NCGA than pepsinogen.

Tooth loss and liver cancer incidence in a Finnish cohort.

PURPOSE: Periodontal disease, a major cause of tooth loss in adults, may have systemic effects and has been associated with higher risk of several cancer types. However, the associations of periodontal disease or tooth loss with liver cancer have only been examined prospectively in two studies, neither of which had sufficient statistical power. In addition, no studies assessed the potential confounding by viral hepatitis or Helicobacter pylori infection status. METHODS: In this study, we examined the association between tooth loss and primary liver cancer incidence in a prospective cohort of Finnish male smokers (n = 29,096). We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios (HRs) and 95% CIs. As a sensitivity analysis, we conducted a nested case-control study within the original cohort to assess confounding by hepatitis B or C virus infection and seropositivity of H. pylori. RESULTS: A total of 213 incident primary liver cancers occurred during a mean follow-up of 17 years. Among these cases, having 11-31 permanent teeth lost (HR 1.42, 95% CI 1.01-1.98) or all 32 teeth lost (HR 1.45, 95% CI 1.00-2.10) was each associated with higher risk of liver cancer, compared to those having 0-10 teeth lost. Adjusting for H. pylori seropositivity yielded a small attenuation of the effect estimate. CONCLUSIONS: Greater number of teeth lost was associated with higher risk of primary liver cancer in our study. The role of periodontal infection in the development of liver cancer warrants further investigation.

Cross sectional study of serum selenium concentration and esophageal squamous dysplasia in western Kenya.

BACKGROUND: Low serum selenium status has been associated with increased risk of esophageal squamous cell carcinoma (ESCC). East Africa is a region of high ESCC incidence and is known to have low soil selenium levels, but this association has not previously been evaluated. In this study we assessed the association of serum selenium concentration and the prevalence of esophageal squamous dysplasia (ESD), the precursor lesion of ESCC, in a cross-sectional study of subjects from Bomet, Kenya. METHODS: 294 asymptomatic adult residents of Bomet, Kenya completed questionnaires and underwent endoscopy with Lugol's iodine staining and biopsy for detection of ESD. Serum selenium concentrations were measured by instrumental neutron activation analysis. Odds ratios (OR) and confidence intervals (95% CI) for associations between serum selenium and ESD were calculated using unconditional logistic regression. RESULTS: The mean serum selenium concentration was 85.5 (±28.3) µg/L. Forty-two ESD cases were identified (14% of those screened), including 5 (12%) in selenium quartile 1 (Q1), 5 (12%) in Q2, 15 (36%) in Q3, and 17 (40%) in Q4. Higher serum selenium was associated with prevalence of ESD (Q4 vs Q1: OR: 3.03; 95% CI: 1.05-8.74) and this association remained after adjusting for potential confounders (Q4 vs Q1: OR: 3.87; 95% CI: 1.06-14.19). CONCLUSION: This is the first study to evaluate the association of serum selenium concentration and esophageal squamous dysplasia in an African population at high risk for ESCC. We found a positive association between higher serum selenium concentration and prevalence of ESD, an association contrary to our original hypothesis. Further work is needed to better understand the role of selenium in the etiology of ESCC in this region, and to develop effective ESCC prevention and control strategies.

Esophageal Squamous Dysplasia is Common in Asymptomatic Kenyans: A Prospective, Community-Based, Cross-Sectional Study.

OBJECTIVES: Esophageal squamous cell carcinoma (ESCC) is endemic in east Africa and is a leading cause of cancer death among Kenyans. The asymptomatic precursor lesion of ESCC is esophageal squamous dysplasia (ESD). We aimed to determine the prevalence of ESD in asymptomatic adult residents of southwestern Kenya. METHODS: In this prospective, community-based, cross-sectional study, 305 asymptomatic adult residents completed questionnaires and underwent video endoscopy with Lugol's iodine chromoendoscopy and mucosal biopsy for detection of ESD. RESULTS: Study procedures were well tolerated, and there were no adverse events. The overall prevalence of ESD was 14.4% (95% confidence interval (CI): 10-19%), including 11.5% with low-grade dysplasia and 2.9% with high-grade dysplasia. The prevalence of ESD was >20% among men aged >50 years and women aged >60 years. Residence location was significantly associated with ESD (Zone A adjusted odds ratio (OR) 2.37, 95% CI: 1.06-5.30 and Zone B adjusted OR 2.72, 95% CI: 1.12-6.57, compared with Zone C). Iodine chromoendoscopy with biopsy of unstained lesions was more sensitive than white-light endoscopy or random mucosal biopsy for detection of ESD and had 67% sensitivity and 70% specificity. CONCLUSIONS: ESD is common among asymptomatic residents of southwestern Kenya and is especially prevalent in persons aged >50 years and those living in particular local regions. Lugol's iodine chromoendoscopy is necessary for detection of most ESD but has only moderate sensitivity and specificity in this setting. Screening for ESD is warranted in this high-risk population, and endoscopic screening of Kenyans is feasible, safe, and acceptable, but more accurate and less invasive screening tests are needed.

A prognostic model for advanced colorectal neoplasia recurrence.

PURPOSE: Following colonoscopic polypectomy, US Multisociety Task Force (USMSTF) guidelines stratify patients based on risk of subsequent advanced neoplasia (AN) using number, size, and histology of resected polyps, but have only moderate sensitivity and specificity. We hypothesized that a state-of-the-art statistical prediction model might improve identification of patients at high risk of future AN and address these challenges. METHODS: Data were pooled from seven prospective studies which had follow-up ascertainment of metachronous AN within 3-5 years of baseline polypectomy (combined n = 8,228). Pooled data were randomly split into training (n = 5,483) and validation (n = 2,745) sets. A prognostic model was developed using best practices. Two risk cut-points were identified in the training data which achieved a 10 percentage point improvement in sensitivity and specificity, respectively, over current USMSTF guidelines. Clinical benefit of USMSTF versus model-based risk stratification was then estimated using validation data. RESULTS: The final model included polyp location, prior polyp history, patient age, and number, size and histology of resected polyps. The first risk cut-point improved sensitivity but with loss of specificity. The second risk cut-point improved specificity without loss of sensitivity (specificity 46.2 % model vs. 42.1 % guidelines, p < 0.001; sensitivity 75.8 % model vs. 74.0 % guidelines, p = 0.64). Estimated AUC was 65 % (95 % CI: 62-69 %). CONCLUSION: This model-based approach allows flexibility in trading sensitivity and specificity, which can optimize colonoscopy over- versus underuse rates. Only modest improvements in prognostic power are possible using currently available clinical data. Research considering additional factors such as adenoma detection rate for risk prediction appears warranted.

Prospective study of Helicobacter pylori antigens and gastric noncardia cancer risk in the nutrition intervention trial cohort.

Helicobacter pylori (H. pylori) infection is the strongest known risk factor for gastric noncardia adenocarcinoma (GNCA). We used multiplex serology to determine whether seropositivity to 15 H. pylori proteins is associated with the subsequent development of noncardia gastric cancer in Linxian, China. We included 448 GNCA cases and 1242 controls from two time points within the Linxian General Population Nutrition Intervention Trial, Linxian. H. pylori multiplex seropositivity was defined as positivity to ≥4 of the 15 included antigens. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for major GNCA risk factors. In addition, we undertook a meta-analysis combining H. pylori multiplex serology data from both time points. H. pylori multiplex seropositivity was associated with a significant increase in risk of GNCA at one time point (1985; OR: 3.44, 95% CI: 1.91, 6.19) and this association remained significant following adjustment for H. pylori or CagA ELISA seropositivity (OR: 2.92, 95% CI: 1.56, 5.47). Combining data from both time points in a meta-analysis H. pylori multiplex seropositivity was associated with an increased risk of GNCA, as were six individual antigens: GroEL, HP0305, CagA, VacA, HcpC and Omp. CagM was inversely associated with risk of GNCA. We identified six individual antigens that confer an increase in risk of GNCA within this population of high H. pylori seroprevalence, as well as a single antigen that may be inversely associated with GNCA risk. We further determined that the H. pylori multiplex assay provides additional information to the conventional ELISA methods on risk of GNCA.

Cancer Risk After Pernicious Anemia in the US Elderly Population.

BACKGROUND & AIMS: Pernicious anemia, a result of autoimmune gastritis, is the most common cause of vitamin B12 deficiency, affecting 2% to 5% of the elderly population. Treatment with vitamin B12 cures the anemia, but not the gastritis. Findings from small studies have indicated that patients with pernicious anemia could have an increased risk of cancer. METHODS: We performed a population-based, case-control study of individuals in the Surveillance, Epidemiology, and End Results-Medicare database, comparing 1,138,390 cancer cases (age, 66-99 y) with 100,000 matched individuals without cancer (controls). Individuals with pernicious anemia were identified based on their medical claims within the year before selection for the study. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression, and models were adjusted for sex, age, and calendar year of diagnosis and selection. RESULTS: Compared with controls, we found individuals with pernicious anemia to be at increased risk for noncardia gastric adenocarcinoma (OR, 2.18; 95% CI, 1.94-2.45) and gastric carcinoid tumors (OR, 11.43; 95% CI, 8.90-14.69). In addition, people with pernicious anemia have an increased risk of developing tonsilar cancer (OR, 2.00; 95% CI, 1.40-2.85), hypopharyngeal cancer (OR, 1.92; 95% CI, 1.35-2.73), esophageal squamous cell carcinoma (OR, 2.12; 95% CI, 1.76-2.55), small intestinal cancer (OR, 1.63; 95% CI, 1.32-2.02), liver cancer (OR, 1.49; 95% CI, 1.28- 1.73), myeloma (OR, 1.55; 95% CI, 1.37-1.75), acute myeloid leukemia (OR, 1.68; 95% CI, 1.46-1.93), and myelodysplastic syndrome (OR, 2.87; 95% CI, 2.53-3.26). People with pernicious anemia have a lower risk of rectal cancer than the general population (OR, 0.82; 95% CI, 0.74- 0.92). CONCLUSIONS: In a population-based, case-control study of individuals in the Surveillance, Epidemiology, and End Results-Medicare database, we found individuals with pernicious anemia to have significantly increased risks of gastric carcinoid tumors, adenocarcinomas, and other cancers located throughout the body.

Association of seropositivity to Helicobacter species and biliary tract cancer in the ATBC study.

UNLABELLED: Helicobacter have been detected in human bile and hepatobiliary tissue. Despite evidence that Helicobacter species promote gallstone formation and hepatobiliary tumors in laboratory studies, it remains unclear whether Helicobacter species contribute to these cancers in humans. We used a multiplex panel to assess whether seropositivity to 15 Helicobacter pylori proteins was associated with subsequent incidence of hepatobiliary cancers in the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. We included 64 biliary cancers, 122 liver cancers, and 224 age-matched controls which occurred over the course of 22 years. Helicobacter pylori seropositivity was defined as those positive to ≥ 4 antigens. Odds ratios (OR) and 95% confidence intervals were adjusted for major hepatobiliary cancer risk factors. Among the controls, 88% were seropositive to H. pylori at baseline. Among those who subsequently developed hepatobiliary cancer, the prevalence of seropositivity was higher: 100% for gallbladder cancer, 97% of extrahepatic bile duct cancer, 91% of ampula of Vater cancer, 96% of intrahepatic bile duct cancer, and 94% of hepatocellular carcinoma. Although the OR for gallbladder cancer could not be calculated, the OR for the other sites were 7.01 (95% confidence interval [CI]: 0.79-62.33), 2.21 (0.19-25.52), 10.67 (0.76-150.08), and 1.20 (0.42-3.45), respectively, with an OR of 5.47 (95% CI: 1.17-25.65) observed for the biliary tract cancers combined. ORs above 1 were observed for many of the investigated antigens, although most of these associations were not statistically significant. CONCLUSION: Seropositivity to H. pylori proteins was associated with an increased risk of biliary tract cancers in ATBC. Further studies are needed to confirm our findings and to determine how H. pylori might influence the risk of biliary tract cancer.