Abdominal and gluteofemoral size and risk of liver cancer: The liver cancer pooling project.

Obesity is known to be associated with primary liver cancer (PLC), but the separate effects of excess abdominal and gluteofemoral size are unclear. Thus, we examined the association between waist and hip circumference with risk of PLC overall and by histologic type-hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). The Liver Cancer Pooling Project is a consortium of prospective cohort studies that include data from 1,167,244 individuals (PLC n = 2,208, HCC n = 1,154, ICC n = 335). Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CI) were estimated using proportional hazards regression. Waist circumference, per 5 cm increase, was associated with an 11% increased PLC risk (HR = 1.11, 95%CI: 1.09-1.14), including when adjusted for hip circumference (HR = 1.12, 95%CI: 1.08-1.17) and also when restricted to individuals in a normal body mass index (BMI) range (18.5 to <25 kg/m2 ; HR = 1.14, 95%CI: 1.07-1.21). Hip circumference, per 5 cm increase, was associated with a 9% increased PLC risk (HR = 1.09, 95%CI: 1.06-1.12), but no association remained after adjustment for waist circumference (HR = 0.99, 95%CI: 0.94-1.03). HCC and ICC results were similar. These findings suggest that excess abdominal size is associated with an increased risk of liver cancer, even among individuals considered to have a normal BMI. However, excess gluteofemoral size alone confers no increased risk. Our findings extend prior analyses, which found an association between excess adiposity and risk of liver cancer, by disentangling the separate effects of excess abdominal and gluteofemoral size through utilization of both waist and hip circumference measurements.

Obesity, diabetes, serum glucose, and risk of primary liver cancer by birth cohort, race/ethnicity, and sex: Multiphasic health checkup study.

OBJECTIVE: Obesity and diabetes have been associated with liver cancer. However, recent US-based studies have suggested a lack of association between obesity and liver cancer among blacks and women. METHODS: We conducted a nested case-control study within the Multiphasic Health Checkup (MHC) cohort of Kaiser Permanente Northern California (KPNC) members. Liver cancer was diagnosed using the KPNC Cancer Registry. Detailed self-administered questionnaires and a standardized examination that included measurement of height and weight and a 1-h glucose tolerance test were completed prior to diagnosis of liver cancer for cases (n=450) and matched controls (4489). Height and weight were utilized to calculate BMI (kg/m(2)) as a measure of adiposity: underweight (15-≤8.5kg/m(2)), normal weight (18.5-≤25kg/m(2)), overweight (25-≤30kg/m(2)), and obese (≥30kg/m(2)). Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) for the association between BMI, diabetes, and serum glucose with subsequent incidence of liver cancer, in models that were stratified by birth cohort, race/ethnicity, and sex. RESULTS: Compared to normal weight individuals, obese individuals had a 2.4-fold increased risk of liver cancer (OR=2.38, 95% CI: 1.68-3.36), and overweight individuals had a 32% increased risk (OR=1.32, 95% CI: 1.03-1.70). This association did not differ when stratified by birth cohort, race/ethnicity, or sex (pint>0.05). Among blacks and women, obesity was associated with at least a 2-fold increased risk of liver cancer (OR=2.29, 95% CI: 1.22-4.28 and OR=2.00, 95% CI: 1.14-3.52, respectively). More moderate increased odds ratios were noted for diabetes (OR=1.28, 95% CI: 0.65-2.54) and serum glucose ≥200mg/dL (OR=1.63, 95% CI: 0.48-5.55), although the results did not attain statistical significance. CONCLUSION: In summary, our finding of a positive association between obesity and liver cancer suggests that a higher BMI may increase the risk of liver cancer in the US, for both sexes and all race/ethnicities.