Valeria Edefonti

Dietary patterns and the risk of colorectal cancer and adenomas

The association of colorectal cancer risk with select foods has been evaluated by dietary pattern analysis. This review of the literature was conducted to thoroughly examine the available evidence for the association between dietary patterns and colorectal cancers and adenomas. A total of 32 articles based on worldwide epidemiological studies were identified. Pattern identification was achieved by exploratory data analyses (principal component, factor, and cluster analyses) in most articles, and only a few used a priori-defined scores. Dietary patterns named as healthy, prudent, fruit and vegetables, fat-reduced/diet foods, vegetable/fish/poultry, fruit/whole grain/dairy, and healthy eating index-2005, recommended food and Mediterranean diet scores were all associated with reduced risk of colorectal cancer and the risk estimates varied from 0.45 to 0.90. In contrast, diets named Western, pork-processed meat-potatoes, meat-eaters, meat and potatoes, traditional patterns, and dietary risk and life summary scores were associated with increased risk of colorectal cancer with risk estimates varying from 1.18 to 11.7. Dietary patterns for adenomas were consistent with those identified for colorectal cancer.

Nutrient dietary patterns and the risk of breast and ovarian cancers

The issue of diet and breast and ovarian cancers has been considered in terms of foods and nutrients, but rarely in terms of dietary patterns. We examined the associations between dietary patterns and breast and ovarian cancers in 2 Italian multicentric case–control studies. Cases were 2,569 breast cancers and 1,031 ovarian cancers hospitalized in 4 Italian areas between 1991 and 1999. Controls were 3,413 women from the same hospital network. Dietary habits were investigated through a validated food‐frequency questionnaire. Dietary patterns were identified on a selected set of nutrients through principal component factor analysis. Odds ratios (OR) and 95% confidence intervals (CI) for both cancers were estimated using unconditional multiple logistic regression models on quartiles of factor scores and continuous factor scores. We identified 4 major dietary patterns named Animal products, Vitamins and fiber, Unsaturated fats and Starch‐rich. The animal products pattern and the unsaturated fats pattern were inversely associated with breast cancer (OR = 0.74, 95% CI: 0.61–0.91 and OR = 0.83, 95% CI: 0.68–1.00, respectively, for the highest consumption quartile), whereas the starch‐rich pattern was directly associated with it (OR = 1.34, 95% CI: 1.10–1.65). The vitamins and fiber pattern was inversely associated with ovarian cancer (OR = 0.77, 95% CI: 0.61–0.98), whereas the starch‐rich pattern was directly associated with it (OR = 1.85, 95% CI: 1.37–2.48). In conclusion, the starch‐rich pattern is potentially an unfavorable indicator of risk for both breast and ovarian cancers, while the animal products and the vitamins and fiber patterns may be associated with a reduced risk of breast and ovarian cancers, respectively.

Dietary patterns and breast cancer: a review with focus on methodological issues

Available information on dietary patterns (multiple dietary components operationalized as a single exposure) and cancer is still sparse. This review presents papers published to date that have identified dietary patterns according to all the existing approaches and have assessed their association with breast cancer. Nineteen articles published since 1995 were identified based on studies conducted in various populations across many countries. The majority of them identified a posteriori dietary patterns, mainly using principal component factor analysis. Six studies did not find associations between any of the identified dietary patterns and breast cancer. Nine studies identified one dietary pattern significantly associated with breast cancer, and the remaining four identified two to four dietary patterns related to breast cancer. Although the body of literature has recently increased, a meaningful assessment of the association between dietary patterns and breast cancer still calls for extra effort to refine the statistical techniques and to address the issue of reproducibility of dietary patterns.

Family history of liver cancer and hepatocellular carcinoma.

Familial clustering of hepatocellular carcinoma (HCC) has been frequently reported in eastern Asiatic countries, where hepatitis B infection is common. Little is known about the relationship between family history of liver cancer and HCC in Western populations. We carried out a case‐control study in Italy, involving 229 HCC cases and 431 hospital controls. Data on family history were summarized through a binary indicator (yes/no) and a family history score (FHscore), considering selected family characteristics. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained from unconditional multiple logistic regression models, including terms for age, sex, study center, education, tobacco smoking, alcohol drinking, hepatitis B surface antigen, and/or anti–hepatitis C virus positivity. We also performed a meta‐analysis on family history of liver cancer and liver cancer updated to April 2011 using random‐effects models. After adjustment for chronic infection with hepatitis B/C viruses, family history of liver cancer was associated with HCC risk, when using both the binary indicator (OR, 2.38; 95% CI, 1.01‐5.58) and the FHscore, with increasing ORs for successive score categories. Compared to subjects without family history and no chronic infection with hepatitis B/C viruses, the OR for those exposed to both risk factors was 72.48 (95% CI, 21.92‐239.73). In the meta‐analysis, based on nine case‐control and four cohort studies, for a total of approximately 3,600 liver cancer cases, the pooled relative risk for family history of liver cancer was 2.50 (95% CI, 2.06‐3.03). Conclusion: A family history of liver cancer increases HCC risk, independently of hepatitis. The combination of family history of liver cancer and hepatitis B/C serum markers is associated with an over 70‐fold elevated HCC risk. (HEPATOLOGY 2011)

Estimating and explaining the effect of education and income on head and neck cancer risk: INHANCE consortium pooled analysis of 31 case-control studies from 27 countries

Low socioeconomic status has been reported to be associated with head and neck cancer risk. However, previous studies have been too small to examine the associations by cancer subsite, age, sex, global region and calendar time and to explain the association in terms of behavioral risk factors. Individual participant data of 23,964 cases with head and neck cancer and 31,954 controls from 31 studies in 27 countries pooled with random effects models. Overall, low education was associated with an increased risk of head and neck cancer (OR = 2.50; 95% CI = 2.02 – 3.09). Overall one‐third of the increased risk was not explained by differences in the distribution of cigarette smoking and alcohol behaviors; and it remained elevated among never users of tobacco and nondrinkers (OR = 1.61; 95% CI = 1.13 – 2.31). More of the estimated education effect was not explained by cigarette smoking and alcohol behaviors: in women than in men, in older than younger groups, in the oropharynx than in other sites, in South/Central America than in Europe/North America and was strongest in countries with greater income inequality. Similar findings were observed for the estimated effect of low versus high household income. The lowest levels of income and educational attainment were associated with more than 2‐fold increased risk of head and neck cancer, which is not entirely explained by differences in the distributions of behavioral risk factors for these cancers and which varies across cancer sites, sexes, countries and country income inequality levels.

Family history of cancer and the risk of cancer: a network of case–control studies

BACKGROUND The risk of many cancers is higher in subjects with a family history (FH) of cancer at a concordant site. However, few studies investigated FH of cancer at discordant sites. PATIENTS AND METHODS This study is based on a network of Italian and Swiss case-control studies on 13 cancer sites conducted between 1991 and 2009, and including more than 12 000 cases and 11 000 controls. We collected information on history of any cancer in first degree relatives, and age at diagnosis. Odds ratios (ORs) for FH were calculated by multiple logistic regression models, adjusted for major confounding factors. RESULTS All sites showed an excess risk in relation to FH of cancer at the same site. Increased risks were also found for oral and pharyngeal cancer and FH of laryngeal cancer (OR = 3.3), esophageal cancer and FH of oral and pharyngeal cancer (OR = 4.1), breast cancer and FH of colorectal cancer (OR = 1.5) and of hemolymphopoietic cancers (OR = 1.7), ovarian cancer and FH of breast cancer (OR = 2.3), and prostate cancer and FH of bladder cancer (OR = 3.4). For most cancer sites, the association with FH was stronger when the proband was affected at age <60 years. CONCLUSIONS Our results point to several potential cancer syndromes that appear among close relatives and may indicate the presence of genetic factors influencing multiple cancer sites.

Nutrient-Based Dietary Patterns and Laryngeal Cancer: Evidence from an Exploratory Factor Analysis

Background: The issue of diet and laryngeal cancer has been rarely addressed considering the potential role of dietary patterns. Methods: We examined this association using data from a case-control study carried out between 1992 and 2000. Cases were 460 histologically confirmed incident laryngeal cancers hospitalized in two Italian areas. Controls were 1,088 subjects hospitalized for acute nonneoplastic diseases unrelated to tobacco or alcohol consumption. Dietary habits were investigated through a 78-item food frequency questionnaire. A posteriori dietary patterns were identified through principal component factor analysis carried out on a selected set of 28 major nutrients. The internal reproducibility, robustness, and reliability of the identified patterns were evaluated. Odds ratios (OR) of laryngeal cancer and 95% confidence intervals (95% CI) were estimated using unconditional multiple logistic regression models on quartiles of factor scores. Results: We identified five major dietary patterns named “animal products,” “starch-rich,” “vitamins and fiber,” “vegetable unsaturated fatty acids,” and “animal unsaturated fatty acids.” The vitamins and fiber dietary pattern was inversely associated with laryngeal cancer (OR, 0.35; 95% CI, 0.24-0.52 for the highest versus the lowest score quartile), whereas the animal products (OR, 2.34; 95% CI, 1.59-3.45) and the animal unsaturated fatty acids (OR, 2.07; 95% CI, 1.42-3.01) patterns were directly associated with it. There was no significant association between the vegetable unsaturated fatty acids and the starch-rich patterns and laryngeal cancer risk. Conclusion: These findings suggest that diets rich in animal products and animal fats are directly related, and those rich in fruit and vegetables inversely related, to laryngeal cancer risk. Cancer Epidemiol Biomarkers Prev; 19(1); 18–27

Estimating and explaining the effect of education and income on head and neck cancer risk

Low socioeconomic status has been reported to be associated with head and neck cancer risk. However, previous studies have been too small to examine the associations by cancer subsite, age, sex, global region and calendar time and to explain the association in terms of behavioral risk factors. Individual participant data of 23,964 cases with head and neck cancer and 31,954 controls from 31 studies in 27 countries pooled with random effects models. Overall, low education was associated with an increased risk of head and neck cancer (OR = 2.50; 95% CI = 2.02 – 3.09). Overall one‐third of the increased risk was not explained by differences in the distribution of cigarette smoking and alcohol behaviors; and it remained elevated among never users of tobacco and nondrinkers (OR = 1.61; 95% CI = 1.13 – 2.31). More of the estimated education effect was not explained by cigarette smoking and alcohol behaviors: in women than in men, in older than younger groups, in the oropharynx than in other sites, in South/Central America than in Europe/North America and was strongest in countries with greater income inequality. Similar findings were observed for the estimated effect of low versus high household income. The lowest levels of income and educational attainment were associated with more than 2‐fold increased risk of head and neck cancer, which is not entirely explained by differences in the distributions of behavioral risk factors for these cancers and which varies across cancer sites, sexes, countries and country income inequality levels.

Dietary patterns and upper aerodigestive tract cancers: an overview and review

BACKGROUND The relationship between diet and cancers of the upper aerodigestive tract (UADT) has been investigated through dietary patterns. DESIGN Published studies on the relationship between a priori and a posteriori dietary patterns and UADT cancers were selected through a Medline search. RESULTS Twenty-four case-control studies were identified. Most of them identified a posteriori dietary patterns, mainly using principal component factor analysis, and a few used a priori dietary patterns, based on the available evidence on known effects of dietary habits on UADT cancers. In one study, no association was found between the identified patterns and UADT cancers. All the remaining 23 papers reported at least one favorable or unfavorable dietary pattern related to UADT cancers. The most consistent findings are the beneficial role of a dietary pattern based on fruit and vegetables or nutrients mostly contained in such foods, and the unfavorable role of an alcohol drinker pattern. A possible unfavorable role of patterns based on meats and animal products emerged as well. CONCLUSION The consistency of results among populations indicates that diets rich in fruit and vegetables, and poor in alcohol and animal products are favorable for UADT cancers.BACKGROUND The relationship between diet and cancers of the upper aerodigestive tract (UADT) has been investigated through dietary patterns. DESIGN Published studies on the relationship between a priori and a posteriori dietary patterns and UADT cancers were selected through a Medline search. RESULTS Twenty-four case-control studies were identified. Most of them identified a posteriori dietary patterns, mainly using principal component factor analysis, and a few used a priori dietary patterns, based on the available evidence on known effects of dietary habits on UADT cancers. In one study, no association was found between the identified patterns and UADT cancers. All the remaining 23 papers reported at least one favorable or unfavorable dietary pattern related to UADT cancers. The most consistent findings are the beneficial role of a dietary pattern based on fruit and vegetables or nutrients mostly contained in such foods, and the unfavorable role of an alcohol drinker pattern. A possible unfavorable role of patterns based on meats and animal products emerged as well. CONCLUSION The consistency of results among populations indicates that diets rich in fruit and vegetables, and poor in alcohol and animal products are favorable for UADT cancers.

A meta-analysis of coffee consumption and pancreatic cancer

BACKGROUND Since when in 1981 a case-control study showed a positive association between coffee and pancreatic cancer, several studies reported inconsistent results on this issue. MATERIALS AND METHODS We conducted a systematic bibliography search updated March 2011 to identify observational studies providing quantitative estimates for pancreatic cancer risk in relation to coffee consumption. We used a meta-analytic approach to estimate overall relative risk (RR) and 95% confidence interval (CI) for the highest versus the lowest coffee consumption categories, using random-effects models. RESULTS Based on 37 case-control and 17 cohort studies (10,594 cases), the pooled RR for the highest versus lowest intake was 1.13 (95% CI 0.99-1.29). Considering only the smoking-adjusting studies, the pooled RRs were 1.10 (95% CI 0.92-1.31) for the 22 case-control, 1.04 (95% CI 0.80-1.36) for the 15 cohort, and 1.08 (95% CI 0.94-1.25) for all studies. The pooled RR for the increment of one cup of coffee per day was 1.03 (95% CI 0.99-1.06) for the 28 smoking-adjusting studies reporting three or more coffee consumption categories. No significant heterogeneity was observed across strata of study design, sex, geographic region, and other selected characteristics. CONCLUSIONS This meta-analysis provides quantitative evidence that coffee consumption is not appreciably related to pancreatic cancer risk, even at high intakes.