Body size and the risk of biliary tract cancer: a population-based study in China

Abstract

Though obesity is an established risk factor for gall bladder cancer, its role in cancers of the extrahepatic bile ducts and ampulla of Vater is less clear, as also is the role of abdominal obesity. In a population-based case -control study of biliary tract cancer in Shanghai, China, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for biliary tract cancer in relation to anthropometric measures, including body mass index (BMI) at various ages and waist-to-hip ratio (WHR), adjusting for age, sex, and education. The study included 627 patients with biliary tract cancer (368 gall bladder, 191 bile duct, 68 ampulla of Vater) and 959 healthy subjects randomly selected from the population. A higher BMI at all ages, including early adulthood (ages 20 -29 years), and a greater WHR were associated with an increased risk of gall bladder cancer. A high usual adult BMI (X25.0) was associated with a 1.6-fold risk of gall bladder cancer (95% CI 1.2 -2.1, P for trend o0.001). Among subjects without gallstones, BMI was also positively associated with gall bladder cancer risk. Regardless of BMI levels, increasing WHR was associated with an excess risk of gall bladder cancer risk, with those having a high BMI (X25) and a high WHR (40.90) having the highest risk of gall bladder cancer (OR ¼ 12.6, 95% CI 4.8 -33.2), relative to those with a low BMI and WHR. We found no clear risk patterns for cancers of the bile duct and ampulla of Vater. These results suggest that both overall and abdominal obesity, including obesity in early adulthood, are associated with an increased risk of gall bladder cancer. The increasing prevalence of obesity and cholesterol stones in Shanghai seems at least partly responsible for the rising incidence of gall bladder cancer in Shanghai.

Risk Factors of Prostate Cancer: a Case-control Study in Faisalabad, Pakistan

“…This is similar to Asia-Pacific region (9.9 per 100,000) but much lower than the whole world (32.8 per 100,000) (Baade et al, 2013). The incidence and mortality rates of prostate cancer are remarkably different in various geographic regions with highest rate in northern America and the lowest in Asia (Hsing et al, 2000). The incidence rate per 100,000 is 119.9 in northern America, 35.5 in southern Europe, 17.3 in eastern Europe, 10.9 in western Asia and 7 in east Asia .…”

Variants in circadian genes and prostate cancer risk: a population-based study in China

“…2 Although a chronic high-fat diet amplified the daily oscillations in glucose tolerance and insulin sensitivity, these mutant mice were protected against the development of frank diabetes. Because obesity is a major hypothesis for prostate tumorigenesis, [16][17][18][19]30,31 it is plausible that the interplay between circadian genes and metabolic processes such as insulin-action may also contribute to altering prostate cancer risk. An alternative mechanism by which circadian genes may affect the prostate cancer risk (that was not explored in this study) is through their effect on sex hormone levels in serum, in particular androgens, 15 because prostate cancer is a hormone-dependent malignancy.…”

“…[16][17][18]20,21 In brief, newly diagnosed primary prostate cancer cases (International Classification of Diseases 9 code 185) were identified through a rapid reporting system established between the Shanghai Cancer Institute and 28 collaborating hospitals in urban Shanghai, between 1993 and 1995. In-person interviews were conducted, using a structured questionnaire, to collect demographic characteristics information that included smoking history and alcohol use.…”

“…Furthermore, Clock mutant mice that had a greatly attenuated diurnal feeding rhythm, were hyperphagic and obese, and developed metabolic syndrome that included hypoinsulinemia. 3 Since many of the phenotypes described for Clock and Bmal1 mutant mice are also the putative risk factors for prostate cancer, [16][17][18][19] it is important to determine if circadian genes can interact with indicators of obesity and insulin resistance in modifying prostate cancer risk.…”

Overweight, obesity and the risk of gallbladder and extrahepatic bile duct cancers: A meta‐analysis of observational studies

“…After full-text review of the remaining 31 studies, two studies were excluded because one study did not report RR with the corresponding 95% CI and the other study did not provide sufficient data to calculate them. Thus, 14 (7,(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47) cohort studies and 15 (19,(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60)(61) case-control studies were included in this meta-analysis.…”