International Agency for Research on Cancer

About: International Agency for Research on Cancer is a government organization based out in Lyon, France. It is known for research contribution in the topics: Cancer & Population. The organization has 2989 authors who have published 9010 publications receiving 929752 citations. The organization is also known as: IARC.

Bias in dietary-report instruments and its implications for nutritional epidemiology.

Abstract: Objective To evaluate measurement error structure in dietary assessment instruments and to investigate its implications for nutritional studies, using urinary nitrogen excretion as a reference biomarker for protein intake. Design The dietary assessment methods included different food-frequency questionnaires (FFQs) and such conventional dietary-report reference instruments as a series of 24-hour recalls, 4-day weighed food records or 7-day diaries. Setting Six original pilot validation studies within the European Prospective Investigation of Cancer (EPIC), and two validation studies conducted by the British Medical Research Council (MRC) within the Norfolk cohort that later joined as a collaborative component cohort of EPIC. Subjects A sample of approximately 100 to 200 women and men, aged 35-74 years, from each of eight validation studies. Results In assessing protein intake, all conventional dietary-report reference methods violated the critical requirements for a valid reference instrument for evaluating, and adjusting for, dietary measurement error in an FFQ. They displayed systematic bias that depended partly on true intake and partly was person-specific, correlated with person-specific bias in the FFQ. Using the dietary-report methods as reference instruments produced substantial overestimation (up to 230%) of the FFQ correlation with true usual intake and serious underestimation (up to 240%) of the degree of attenuation of FFQ-based log relative risks. Conclusion The impact of measurement error in dietary assessment instruments on the design, analysis and interpretation of nutritional studies may be much greater than has been previously estimated, at least regarding protein intake.

A 2-Year Prospective Study of Human Papillomavirus Persistence among Women with a Cytological Diagnosis of Atypical Squamous Cells of Undetermined Significance or Low-Grade Squamous Intraepithelial Lesion

Abstract: Background Cervical cancer is caused by persistent infection with human papillomavirus (HPV). Most infections and associated lesions clear spontaneously. It is important to define the determinants and timing of clearance, so that viral persistence can be recognized and managed. Methods We investigated HPV natural history among 4504 subjects from ALTS (Atypical Squamous Cells of Undetermined Significance/Low-Grade Squamous Intraepithelial Lesions Triage Study). A discrete-time Markov model was used to simultaneously describe the prevalence, incidence, and persistence of type-specific HPV infection over 24 months in women with equivocal or mildly abnormal cytological results. Interactions between multiple HPV types infecting the same woman were examined for incidence of new infection (after an HPV-16 infection) and persistence of a current infection within groups defined by phylogenetic relatedness or by carcinogenicity. Results Ninety-one percent (95% credible interval [CI], 90%-92%) of prevalent HPV infections at enrollment cleared within 24 months. The probability that an infection would persist for a further 6 months increased with the duration of infection, from 37% (95% CI, 35%-39%) for a newly observed infection to 65% (95% CI, 61%-70%) for an infection that had already persisted for > or =18 months. No consistent evidence of interactions was found between multiple HPV types regarding the incidence of new infection after an HPV-16 infection or regarding persistence of current HPV infection. Conclusion Although virtually all HPV infections clear within 2 years, the remaining infections have a high potential for persistence and, by implication, progression to precancer and cancer. Once biological and behavioral determinants are controlled for, HPV infections with different types seem to be independent of each other.

Fusobacterium nucleatum associates with stages of colorectal neoplasia development, colorectal cancer and disease outcome

Abstract: Commensal bacteria in the colon may play a role in colorectal cancer (CRC) development. Recent studies from North America showed that Fusobacterium nucleatum (Fn) infection is over-represented in disease tissue versus matched normal tissue in CRC patients. Using quantitative real-time polymerase chain reaction (qPCR) of DNA extracted from colorectal tissue biopsies and surgical resections of three European cohorts totalling 122 CRC patients, we found an over-abundance of Fn in cancerous compared to matched normal tissue (p < 0.0001). To determine whether Fn infection is an early event in CRC development, we assayed Fn in colorectal adenoma (CRA) tissue from 52 Irish patients. While for all CRAs the Fn level was not statistically significantly higher in disease versus normal tissue (p = 0.06), it was significantly higher for high-grade dysplasia (p = 0.015). As a secondary objective, we determined that CRC patients with low Fn levels had a significantly longer overall survival time than patients with moderate and high levels of the bacterium (p = 0.008). The investigation of Fn as a potential non-invasive biomarker for CRC screening showed that, while Fn was more abundant in stool samples from CRC patients compared to adenomas or controls, the levels in stool did not correlate with cancer or adenoma tissue levels from the same individuals. This is the first study examining Fn in the colonic tissue and stool of European CRC and CRA patients, and suggests Fn as a novel risk factor for disease progression from adenoma to cancer, possibly affecting patient survival outcomes. Our results highlight the potential of Fn detection as a diagnostic and prognostic determinant in CRC patients.

Review article: Epidemiology of male breast cancer. A meta‐analysis of published case‐control studies and discussion of selected aetiological factors

Abstract: Male breast cancer is a rare tumour in all parts of the world. About 1% of all breast cancers occur in men, but the male/female ratio is higher among black than among white populations. This effect can be seen in US cancer registries and even more markedly in African data. A positive correlation exists on a population scale between male breast cancer and prostate cancer. Seven case-control studies of male breast cancer are available, and a pooled analysis was conducted of the most commonly suspected risk factors. Male breast cancer appears to be associated with marital status: Mantel-Haenszel exposure odds ratio (EOR) for never married = 1.6; 95% confidence limits (CL) = 1.1, 2.3, religion (EOR for being Jewish = 2.1; 95% CL = 1.4, 3.2), previous breast pathology (EOR for positive history of benign breast disease = 2.7; 95% CL = 1.7, 4.2), gynaecomastia (EOR for positive history = 6.2, 95% CL = 3.4, 11.4), previous testicular pathology (EOR for positive history = 2.2; 95% CL = 1.5, 3.3), previous liver diseases (EOR for positive history = 1.6; 95% CL = 1.0, 2.4) and family history of breast cancer (EOR for first-degree relative with breast cancer = 2.5; 95% CL = 1.7, 3.7). No association is found with smoking history. Other potential risk factors such as reproductive history, education, occupation, anthropometric variables, association with various diseases, and specific exposures such as drug use, were not systematically evaluated in all studies and provide sometimes contradictory results, possibly due to small numbers of exposed subjects. Overall, the analytical epidemiology of male breast cancer presents similarities with the epidemiology of female breast cancer, with a potential role of factors related to hormonal status, relative hyperoestrogeny in men being potentially linked to increased risk of disease. Genetics may also play a role, with high risk linked to a familial history of breast cancer, and with a major risk in patients with Klinefelter's syndrome.

Standardization of the 24-hour diet recall calibration method used in the european prospective investigation into cancer and nutrition (EPIC): general concepts and preliminary results.

Abstract: Objectives: Despite increasing interest in the concept of calibration in dietary surveys, there is still little experience in the use and standardization of a common reference dietary method, especially in international studies. In this paper, we present the general theoretical framework and the approaches developed to standardize the computer-assisted 24 h diet recall method (EPIC-SOFT) used to collect about 37 000 24-h dietary recall measurements (24-HDR) from the 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). In addition, an analysis of variance was performed to examine the level of standardization of EPIC-SOFT across the 90 interviewers involved in the study. Methods: The analysis of variance used a random effects model in which mean energy intake per interviewer was used as the dependent variable, while age, body mass index (BMI), energy requirement, week day, season, special diet, special day, physical activity and the EPIC-SOFT version were used as independent variables. The analysis was performed separately for men and women. Results: The results show no statistical difference between interviewers in all countries for men and five out of eight countries for women, after adjustment for physical activity and the EPIC-SOFT program version used, and the exclusion of one interviewer in Germany (for men), and one in Denmark (for women). These results showed an interviewer effect in certain countries and a significant difference between gender, suggesting an underlying respondent’s effect due to the higher under-reporting among women that was consistently observed in EPIC. However, the actual difference between interviewer and country mean energy intakes is about 10%. Furthermore, no statistical differences in mean energy intakes were observed across centres from the same country, except in Italy and Germany for men, and France and Spain for women, where the populations were recruited from areas scattered throughout the countries. Conclusion: Despite these encouraging results and the efforts to standardize the 24-HDR interview method, conscious or unconscious behaviour of respondents and/or interviewer bias cannot be prevented entirely. Further evaluation of the reliability of EPIC-SOFT measurements will be conducted through validation against independent biological markers (nitrogen, potassium). European Journal of Clinical Nutrition (2000) 54, 900–917