Background Tobacco and alcohol are well-established risk factors for numerous cancers, yet their relationship to biliary tract cancers remains unclear. Methods We pooled data from 26 prospective studies to evaluate associations of cigarette smoking and alcohol consumption with biliary tract cancer risk. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for associations with smoking and alcohol consumption were calculated. Random-effects meta-analysis produced summary estimates. All statistical tests were two-sided. Results Over a period of 38 369 156 person-years of follow-up, 1391 gallbladder, 758 intrahepatic bile duct, 1208 extrahepatic bile duct, and 623 ampulla of Vater cancer cases were identified. Ever, former, and current smoking were associated with increased extrahepatic bile duct and ampulla of Vater cancers risk (eg, current vs never smokers HR = 1.69, 95% CI = 1.34 to 2.13 and 2.22, 95% CI = 1.69 to 2.92, respectively), with dose-response effects for smoking pack-years, duration, and intensity (all Ptrend < .01). Current smoking and smoking intensity were also associated with intrahepatic bile duct cancer (eg, >40 cigarettes per day vs never smokers HR = 2.15, 95 % CI = 1.15 to 4.00; Ptrend = .001). No convincing association was observed between smoking and gallbladder cancer. Alcohol consumption was only associated with intrahepatic bile duct cancer, with increased risk for individuals consuming five or more vs zero drinks per day (HR = 2.35, 95%CI = 1.46 to 3.78; Ptrend = .04). There was evidence of statistical heterogeneity among several cancer sites, particularly between gallbladder cancer and the other biliary tract cancers. Conclusions Smoking appears to increase the risk of developing all biliary tract cancers except gallbladder cancer. Alcohol may increase the risk of intrahepatic bile duct cancer. Findings highlight etiologic heterogeneity across the biliary tract.

Obesity and metabolic syndrome (MetS) are key risk factors for chronic disease. Dietary patterns are critical in the incidence and persistence of obesity and MetS, yet there is few data linking diet to obesity and MetS in Chile. Our objective was to use a locally validated diet index to evaluate adherence to a Mediterranean dietary pattern and its correlations with overweight/obesity (OW/O) and MetS prevalence in Chilean adults. We conducted a nationwide, cross-sectional online survey of Chilean adults with complete self-reported diet and body mass index data (n = 24,882). A subsample of 4348 users (17.5%) had valid MetS data. An inverse association was observed between adherence to Mediterranean diet and OW/O and MetS prevalence. As diet quality decreased from healthy, to moderately-healthy, to unhealthy, prevalence increased from 44.8, 51.1, to 60.9% for OW/O and from 13.4, 18.5, to 28.9% for MetS (p-values < 0.001). Adjusted odds ratios for OW/O and MetS were significantly higher in moderately-healthy (OR = 1.58 and 1.54) and unhealthy (OR = 2.20 and 2.49, respectively) diet groups in comparison to the healthy diet group. This study represents the first report on the relationship between Mediterranean diet and chronic disease risk in Chile. It suggests that the Mediterranean diet may be applied to manage chronic disease risk beyond the Mediterranean basin.

This study found four circulating ILs that were associated with gallstones. Future studies are needed to validate the findings and evaluate the common pathway or mechanism in the development of gallbladder diseases associated with these cytokine signatures.

Growing evidence suggests that people with autoimmune conditions may be at increased risk of hepatobiliary tumors. In the present study, we evaluated associations between autoimmune conditions and hepatobiliary cancers among adults aged ≥66 in the United States. We used Surveillance, Epidemiology, and End Results (SEER)-Medicare data (1992-2013) to conduct a population-based, case-control study. Cases (n = 32,443) had primary hepatobiliary cancer. Controls (n = 200,000) were randomly selected, cancer-free adults frequency-matched to cases by sex, age and year of selection. Using multivariable logistic regression, we calculated odds ratios (ORs) and 95% confidence intervals (CIs) for associations with 39 autoimmune conditions identified via Medicare claims. We also conducted separate analyses for diagnoses obtained via inpatient versus outpatient claims. Sixteen conditions were associated with at least one hepatobiliary cancer. The strongest risk estimates were for primary biliary cholangitis with hepatocellular carcinoma (OR: 31.33 [95% CI: 23.63-41.56]) and primary sclerosing cholangitis with intrahepatic cholangiocarcinoma (7.53 [5.73-10.57]), extrahepatic cholangiocarcinoma (5.59 [4.03-7.75]), gallbladder cancer (2.06 [1.27-3.33]) and ampulla of Vater cancer (6.29 [4.29-9.22]). Associations with hepatobiliary-related conditions as a group were observed across nearly all cancer sites (ORs ranging from 4.53 [95% CI: 3.30-6.21] for extrahepatic cholangiocarcinoma to 7.18 [5.94-8.67] for hepatocellular carcinoma). Restricting to autoimmune conditions diagnosed via inpatient claims, 6 conditions remained associated with at least one hepatobiliary cancer, and several risk estimates increased. In the outpatient restricted analysis, 12 conditions remained associated. Multiple autoimmune conditions are associated with hepatobiliary cancer risk in the US Medicare population, supporting a shared immuno-inflammatory etiology to these cancers.

Background and Aims Exposure to metals may promote the risk for cancers. We evaluated the associations of a broad spectrum of metals with gallbladder cancer (GBC) and gallstones. Approach and Results A total of 259 patients with GBC, 701 patients with gallstones, and 851 population‐based controls were enrolled in Shanghai, China. A metallome panel was used to simultaneously detect 18 metals in serum through inductively coupled plasma–mass spectrometry. Logistic regression models were used to estimate crude or adjusted odds ratios (ORadj) with 95% confidence intervals (CIs) for the association between metal levels and gallbladder disease. Among the 18 metals tested, 12 were significantly associated with GBC and six with gallstones (Pcorrected < 0.002). Boron, lithium, molybdenum, and arsenic levels were associated with GBC compared to gallstones as well as with gallstones compared to population‐based controls. Elevated levels of cadmium, chromium, copper, molybdenum, and vanadium were positively associated with GBC versus gallstones; and the ORadj for the highest tertile (T3) compared to the lowest tertile (T1) ranged from 1.80 to 7.28, with evidence of dose–response trends (P < 0.05). Arsenic, boron, iron, lithium, magnesium, selenium, and sulfur were inversely associated with GBC, with the T3 versus T1 ORadj ranging from 0.20 to 0.69. Arsenic, boron, calcium, lithium, molybdenum, and phosphorus were negatively associated with gallstones, with the T3 versus T1 ORadj ranging from 0.50 to 0.75 (P < 0.05). Conclusions Metals were associated with both GBC and gallstones, providing cross‐sectional evidence of association across the natural history of disease. Longitudinal studies are needed to evaluate the temporality of metal exposure and gallbladder diseases and to investigate the mechanisms of disease pathogenesis.