The metabolic syndrome is associated with increased risk of colorectal adenoma development: the Self-Defense Forces health study.

The metabolic syndrome, a cluster of metabolic abnormalities linked to insulin resistance, has attracted much interest as a risk factor for cardiovascular disease and type 2 diabetes. Hyperinsulinemia is also a postulated biological risk factor for colorectal carcinogenesis. We therefore here examined the relation between the metabolic syndrome and colorectal adenoma development. The study subjects were 756 cases of colorectal adenoma and 1751 controls with no polyps who underwent total colonoscopy during the period January 1995 to March 2002 at two Self Defense Forces (SDF) hospitals in Japan. The metabolic syndrome was defined with reference to abdominal obesity in combination with any two of the following conditions: elevated triglycerides (150 mg/dL); lowered HDL cholesterol (<40 mg/dL); elevated blood pressure (systolic blood pressure 130 mmHg and/or diastolic blood pressure 85 mmHg); and raised fasting glucose (110 mg/dL). Abdominal obesity was defined as a waist circumference of 85 cm or more(Japanese criterion) or 90 cm (Asian criterion). Statistical adjustment was made for age, hospital, and rank in the SDF. The metabolic syndrome was found to be associated with a moderately increased risk of colorectal adenomas whether either of the Japanese and Asian criteria was used; adjusted odds ratios with the Japanese and Asian criteria were 1.38 (95% confidence interval [CI] 1.13-1.69) and 1.48 (95% CI 1.13-1.93), respectively. Increased risk was more evident for proximal than distal colon or rectal adenomas, and was almost exclusively observed for large lesions (5 mm in diameter). Thus the metabolic syndrome appears to be an important entity with regard to the prevention of colorectal cancer, as well as cardiovascular disease and type 2 diabetes.

Lack of an association between serum level of transforming growth factor beta -1 and stomach cancer risk in the JACC study.

Alterations in the serum concentration of transforming growth factor beta-1 (TGFbeta1) have been observed in gastric cancer patients. No study, however, has ever examined the association between the serum TGFbeta1 level and stomach cancer prospectively. We conducted a prospective, nested case-control analysis among apparently healthy men and women who were followed for up to 8 years in the JACC Study to assess whether serum level of total TGFbeta1 is associated with a subsequent risk of stomach cancer. The concentration of serum TGFbeta1 in previously collected blood samples was analyzed by ELISA for 209 individuals in whom a diagnosis of stomach cancer was documented, and for 409 controls matched with them for gender, age and study area. Baseline blood levels of TGFbeta1 were not related to the risk of stomach cancer in either men or women, a finding unchanged even after adjustment for potential confounders. The multivariate-adjusted odds ratio of stomach cancer in men and women was 1.10 (95% CI, 0.82 to 1.48) and 1.09 (95% CI, 0.80 to 1.48), respectively, for each increase of 1 SD in the TGFbeta1 value. In conclusion, serum TGFbeta1 levels were not associated with increased risks of subsequent stomach cancer.gene A52C polymorphism related to the metabolism of long-chain fatty acids and oxidized LDL in the etiology of colorectal cancer.

A case-control study of colorectal cancer in relation to lifestyle factors and genetic polymorphisms: design and conduct of the Fukuoka colorectal cancer study.

A case-control study was designed to elucidate roles of dietary and other behavioral influences, in combination with genetic susceptibility factors (genetic polymorphisms), in colorectal carcinogenesis. Both cases and controls were residents in Fukuoka City and three adjacent areas. Cases were patients undergoing surgery for a first diagnosis of colorectal cancer at 8 hospitals in the study area, and controls were randomly selected in the community by frequency-matching with respect to the expected distribution by sex, age (10-year class), and residence. Dietary and other lifestyle factors were ascertained by in-person interview, and venous blood was obtained for genotyping and possible biochemical measurements. The cases were interviewed at each hospital during the period from 2000 to 2003, and controls were surveyed during the period from 2001 to 2002. A total of 840 cases of colorectal cancer and 833 controls were interviewed with participation rates of 80% for the cases and 60% for the controls. Informed consent to genotyping was obtained from 685 cases and 778 controls. Further details of the design and conduct are described with respect to methodological aspects.