Showing papers by "International Agency for Research on Cancer published in 2002"

The causal relation between human papillomavirus and cervical cancer

Abstract: The causal role of human papillomavirus infections in cervical cancer has been documented beyond reasonable doubt. The association is present in virtually all cervical cancer cases worldwide. It is the right time for medical societies and public health regulators to consider this evidence and to define its preventive and clinical implications. A comprehensive review of key studies and results is presented.

The WHO Classification of Tumors of the Nervous System

Abstract: The new World Health Organization (WHO) classification of nervous system tumors, published in 2000, emerged from a 1999 international consensus conference of neuropathologists. New entities include chordoid glioma of the third ventricle, cerebellar liponeurocytoma, atypical teratoid/rhabdoid tumor, and perineurioma. Several histological variants were added, including tanycytic ependymoma, large cell medulloblastoma, and rhabdoid meningioma. The WHO grading scheme was updated and, for meningiomas, extensively revised. In recognition of the emerging role of molecular diagnostic approaches to tumor classification, genetic profiles have been emphasized, as in the distinct subtypes of glioblastoma and the already clinically useful 1p and 19q markers for oligodendroglioma and 22q/INI1 for atypical teratoid/rhabdoid tumors. In accord with the new WHO Blue Book series, the actual classification is accompanied by extensive descriptions and illustrations of clinicopathological characteristics of each tumor type, including molecular genetic features, predictive factors, and separate chapters on inherited tumor syndromes. The 2000 WHO classification of nervous system tumors aims at being used and implemented by the neuro-oncology and biomedical research communities worldwide.

European prospective investigation into cancer and nutrition (EPIC): study populations and data collection

Abstract: The European Prospective Investigation into Cancer and Nutrition (EPIC) is an ongoing multi-centre prospective cohort study designed to investigate the relationship between nutrition and cancer, with the potential for studying other diseases as well. The study currently includes 519 978 participants (366 521 women and 153 457 men, mostly aged 35-70 years) in 23 centres located in 10 European countries, to be followed for cancer incidence and cause-specific mortality for several decades. At enrollment, which took place between 1992 and 2000 at each of the different centres, information was collected through a non-dietary questionnaire on lifestyle variables and through a dietary questionnaire addressing usual diet. Anthropometric measurements were performed and blood samples taken, from which plasma, serum, red cells and buffy coat fractions were separated and aliquoted for long-term storage, mostly in liquid nitrogen. To calibrate dietary measurements, a standardised, computer-assisted 24-hour dietary recall was implemented at each centre on stratified random samples of the participants, for a total of 36 900 subjects. EPIC represents the largest single resource available today world-wide for prospective investigations on the aetiology of cancers (and other diseases) that can integrate questionnaire data on lifestyle and diet, biomarkers of diet and of endogenous metabolism (e.g. hormones and growth factors) and genetic polymorphisms. First results of case-control studies nested within the cohort are expected early in 2003. The present paper provides a description of the EPIC study, with the aim of simplifying reference to it in future papers reporting substantive or methodological studies carried out in the EPIC cohort.

The IARC TP53 database: new online mutation analysis and recommendations to users.

Abstract: Mutations in the tumor suppressor gene TP53 are frequent in most human cancers. Comparison of the mutation patterns in different cancers may reveal clues on the natural history of the disease. Over the past 10 years, several databases of TP53 mutations have been developed. The most extensive of these databases is maintained and developed at the International Agency for Research on Cancer. The database compiles all mutations (somatic and inherited), as well as polymorphisms, that have been reported in the published literature since 1989. The IARC TP53 mutation dataset is the largest dataset available on the variations of any human gene. The database is available at www.iarc.fr/P53/. In this paper, we describe recent developments of the database. These developments include restructuring of the database, which is now patient-centered, with more detailed annotations on the patient (carcinogen exposure, virus infection, genetic background). In addition, a new on-line application to retrieve somatic mutation data and analyze mutation patterns is now available. We also discuss limitations on the use of the database and provide recommendations to users.

Low-penetrance susceptibility to breast cancer due to CHEK2(*)1100delC in noncarriers of BRCA1 or BRCA2 mutations

Abstract: Mutations in BRCA1 and BRCA2 confer a high risk of breast and ovarian cancer, but account for only a small fraction of breast cancer susceptibility. To find additional genes conferring susceptibility to breast cancer, we analyzed CHEK2 (also known as CHK2), which encodes a cell-cycle checkpoint kinase that is implicated in DNA repair processes involving BRCA1 and p53 (refs 3,4,5). We show that CHEK2(*)1100delC, a truncating variant that abrogates the kinase activity, has a frequency of 1.1% in healthy individuals. However, this variant is present in 5.1% of individuals with breast cancer from 718 families that do not carry mutations in BRCA1 or BRCA2 (P = 0.00000003), including 13.5% of individuals from families with male breast cancer (P = 0.00015). We estimate that the CHEK2(*)1100delC variant results in an approximately twofold increase of breast cancer risk in women and a tenfold increase of risk in men. By contrast, the variant confers no increased cancer risk in carriers of BRCA1 or BRCA2 mutations. This suggests that the biological mechanisms underlying the elevated risk of breast cancer in CHEK2 mutation carriers are already subverted in carriers of BRCA1 or BRCA2 mutations, which is consistent with participation of the encoded proteins in the same pathway.

Tobacco smoke carcinogens, DNA damage and p53 mutations in smoking-associated cancers

Abstract: It is estimated that cigarette smoking kills over 1 000 000 people each year by causing lung cancer as well as many other neoplasmas. p53 mutations are frequent in tobacco-related cancers and the mutation load is often higher in cancers from smokers than from nonsmokers. In lung cancers, the p53 mutational patterns are different between smokers and nonsmokers with an excess of G to T transversions in smoking-associated cancers. The prevalence of G to T transversions is 30% in smokers' lung cancer but only 12% in lung cancers of nonsmokers. A similar trend exists, albeit less marked, in laryngeal cancers and in head and neck cancers. This type of mutation is infrequent in most other tumors aside from hepatocellular carcinoma. At several p53 mutational hotspots common to all cancers, such as codons 248 and 273, a large fraction of the mutations are G to T events in lung cancers but are almost exclusively G to A transitions in non-tobacco-related cancers. Two important classes of tobacco smoke carcinogens are the polycyclic aromatic hydrocarbons (PAH) and the nicotine-derived nitrosamines. Recent studies have indicated that there is a strong coincidence of G to T transversion hotspots in lung cancers and sites of preferential formation of PAH adducts along the p53 gene. Endogenously methylated CpG dinucleotides are the preferred sites for G to T transversions, accounting for more than 50% of such mutations in lung tumors. The same dinucleotide, when present within CpG-methylated mutational reporter genes, is the target of G to T transversion hotspots in cells exposed to the model PAH compound benzo[a]pyrene-7,8-diol-9,10-epoxide. As summarized here, a number of other tobacco smoke carcinogens also can cause G to T transversion mutations. The available data suggest that p53 mutations in lung cancers can be attributed to direct DNA damage from cigarette smoke carcinogens rather than to selection of pre-existing endogenous mutations.

Obesity, endogenous hormones, and endometrial cancer risk: a synthetic review.

Abstract: Endometrial cancer is a disease of the affluent, developed world, where epidemiological studies have shown that > or =40% of its incidence can be attributed to excess body weight. An additional proportion may be because of lack of physical activity. Alterations in endogenous hormone metabolism may provide the main links between endometrial cancer risk, and excess body weight and physical inactivity. Epidemiological studies have shown increased endometrial cancer risks among pre- and postmenopausal women who have elevated plasma androstenedione and testosterone, and among postmenopausal women who have increased levels of estrone and estradiol. Furthermore, there is evidence that chronic hyperinsulinemia is a risk factor. These relationships can all be interpreted in the light of the "unopposed estrogen" hypothesis, which proposes that endometrial cancer may develop as a result of the mitogenic effects of estrogens, when these are insufficiently counterbalanced by progesterone. In our overall synthesis, we conclude that development of ovarian hyperandrogenism may be a central mechanism relating nutritional lifestyle factors to endometrial cancer risk. In premenopausal women, ovarian hyperandrogenism likely increases risk by inducing chronic anovulation and progesterone deficiency. After the menopause, when progesterone synthesis has ceased altogether, excess weight may continue increasing risk through elevated plasma levels of androgen precursors, increasing estrogen levels through the aromatization of the androgens in adipose tissue. The ovarian androgen excess may be because of an interaction between obesity-related, chronic hyperinsulinemia with genetic factors predisposing to the development of ovarian hyperandrogenism.

Overweight, obesity, and cancer risk

Abstract: Over the past few decades the proportion of people with excess body weight has been increasing in both developed and less developed countries. About 50% of men and 35% of women in Europe are currently estimated to be overweight or obese. In addition to an increase in the risk of cardiovascular disease and type II diabetes, the evidence summarised here shows that excess body weight is directly associated with risk of cancer at several organ sites, including colon, breast (in postmenopausal women), endometrium, oesophagus, and kidney. In part, these associations with cancer risk may be explained by alterations in the metabolism of endogenous hormones-including sex steroids, insulin, and insulin-like growth factors-which can lead to distortion of the normal balance between cell proliferation, differentiation, and apoptosis. Avoidance of weight gain thus seems to be an important factor for cancer prevention.

Age-Specific Prevalence of Infection with Herpes Simplex Virus Types 2 and 1: A Global Review

Abstract: Information on age- and sex-specific prevalence of herpes simplex virus (HSV) types 2 and 1 infections is essential to optimize genital herpes control strategies, which increase in importance because accumulating data indicate that HSV-2 infection may increase acquisition and transmission of human immunodeficiency virus. This review summarizes data from peer-reviewed publications of type-specific HSV seroepidemiologic surveys. HSV-2 prevalence is, in general, highest in Africa and the Americas, lower in western and southern Europe than in northern Europe and North America, and lowest in Asia. HSV-2 and -1 prevalence, overall and by age, varies markedly by country, region within country, and population subgroup. Age-specific HSV-2 prevalence is usually higher in women than men and in populations with higher risk sexual behavior. HSV-2 prevalence has increased in the United States but national data from other countries are unavailable. HSV-1 infection is acquired during childhood and adolescence and is markedly more widespread than HSV-2 infection. Further studies are needed in many geographic areas.

Male circumcision, penile human papillomavirus infection, and cervical cancer in female partners

Abstract: Background It is uncertain whether male circumcision reduces the risks of penile human papillomavirus (HPV) infection in the man and of cervical cancer in his female partner. Methods We pooled data on 1913 couples enrolled in one of seven case–control studies of cervical carcinoma in situ and cervical cancer in five countries. Circumcision status was self-reported, and the accuracy of the data was confirmed by physical examination at three study sites. The presence or absence of penile HPV DNA was assessed by a polymerase-chain-reaction assay in 1520 men and yielded a valid result in the case of 1139 men (74.9 percent). Results Penile HPV was detected in 166 of the 847 uncircumcised men (19.6 percent) and in 16 of the 292 circumcised men (5.5 percent). After adjustment for age at first intercourse, lifetime number of sexual partners, and other potential confounders, circumcised men were less likely than uncircumcised men to have HPV infection (odds ratio, 0.37; 95 percent confidence interval, 0.16 to 0.85...

Estimates of the world-wide prevalence of cancer for 25 sites in the adult population.

Abstract: In health services planning, in addition to the basic measures of disease occurrence incidence and mortality, other indexes expressing the demand of care are also required to develop strategies for service provision. One of these is prevalence of the disease, which measures the absolute number, and relative proportion in the population, of individuals affected by the disease and that require some form of medical attention. For most cancer sites, cases surviving 5 years from diagnosis experience thereafter the same survival as the general population, so most of the workload is therefore due to medical acts within these first 5 years. This article reports world-wide estimates of 1-, 2-3- and 4-5-year point prevalence in 1990 in the population aged 15 years or over, and hence describes the number of cancer cases diagnosed between 1986 and 1990 who were still alive at the end of 1990. These estimates of prevalence at 1, 2-3 and 4-5 years are applicable to the evaluation of initial treatment, clinical follow-up and point of cure, respectively, for the majority of cancers. We describe the computational procedure and data sources utilised to obtain these figures and compare them with data published by 2 cancer registries. The highest prevalence of cancer is in North America with 1.5% of the population affected and diagnosed in the previous 5 years (about 0.5% of the population in years 4-5 and 2-3 of follow-up and 0.4% within the first year of diagnosis). This corresponds to over 3.2 million individuals. Western Europe and Australia and New Zealand show very similar percentages with 1.2% and 1.1% of the population affected (about 3.9 and 0.2 million cases respectively). Japan and Eastern Europe form the next batch with 1.0% and 0.7%, followed by Latin America and the Caribbean (overall prevalence of 0.4%), and all remaining regions are around 0.2%. Cancer prevalence in developed countries is very similar in men and women, 1.1% of the sex-specific population, while in developing countries the prevalence is some 25% greater in women than men, reflecting a preponderance of cancer sites with poor survival such as liver, oesophagus and stomach in males. The magnitude of disease incidence is the primary determinant of crude prevalence of cases diagnosed within 1 year so that differences by region mainly reflect variation in risk. In the long-term period however different demographic patterns with long-life expectancy in high-income countries determine a higher prevalence in these areas even for relatively uncommon cancer sites such as the cervix.

Alcohol and Hepatocellular Carcinoma: The Effect of Lifetime Intake and Hepatitis Virus Infections in Men and Women

Abstract: The authors investigated the dose-effect relation between alcohol drinking and hepatocellular carcinoma (HCC) in men and women separately, also considering hepatitis B and hepatitis C virus infections. They enrolled 464 subjects (380 men) with a first diagnosis of HCC as cases and 824 subjects (686 men) unaffected by hepatic diseases as controls; all were hospitalized in Brescia, northern Italy, in 1995-2000. Spline regression models showed a steady linear increase in the odds ratio of HCC for increasing alcohol intake, for values of >60 g of ethanol per day, with no substantial differences between men and women. Duration of drinking and age at start had no effect on the odds ratio when alcohol intake was considered. Former drinkers who had stopped 1-10 years previously had a higher risk of HCC than current drinkers did. The effect of alcohol drinking was evident even in the absence of hepatitis B or hepatitis C virus infection. In addition, a synergism between alcohol drinking and either infection was found, with approximately a twofold increase in the odds ratio for each hepatitis virus infection for drinkers of >60 g per day.

Meat consumption and colorectal cancer risk: Dose‐response meta‐analysis of epidemiological studies

Abstract: The hypothesis that consumption of red and processed meat increases colorectal cancer risk is reassessed in a meta-analysis of articles published during 1973-99. The mean relative risk (RR) for the highest quantile of intake vs. the lowest was calculated and the RR per gram of intake was computed through log-linear models. Attributable fractions and preventable fractions for hypothetical reductions in red meat consumption in different geographical areas were derived using the RR log-linear estimates and prevalence of red meat consumption from FAO data and national dietary surveys. High intake of red meat, and particularly of processed meat, was associated with a moderate but significant increase in colorectal cancer risk. Average RRs and 95% confidence intervals (CI) for the highest quantile of consumption of red meat were 1.35 (CI: 1.21-1.51) and of processed meat, 1.31 (CI: 1.13-1.51). The RRs estimated by log-linear dose-response analysis were 1.24 (CI: 1.08-1.41) for an increase of 120 g/day of red meat and 1.36 (CI: 1.15-1.61) for 30 g/day of processed meat. Total meat consumption was not significantly associated with colorectal cancer risk. The risk fraction attributable to current levels of red meat intake was in the range of 10-25% in regions where red meat intake is high. If average red meat intake is reduced to 70 g/week in these regions, colorectal cancer risk would hypothetically decrease by 7-24%.

Activation and Caspase-mediated Inhibition of PARP: A Molecular Switch between Fibroblast Necrosis and Apoptosis in Death Receptor Signaling

Abstract: Death ligands not only induce apoptosis but can also trigger necrosis with distinct biochemical and morphological features. We recently showed that in L929 cells CD95 ligation induces apoptosis, whereas TNF elicits necrosis. Treatment with anti-CD95 resulted in typical apoptosis characterized by caspase activation and DNA fragmentation. These events were barely induced by TNF, although TNF triggered cell death to a similar extent as CD95. Surprisingly, whereas the caspase inhibitor zVAD prevented CD95-mediated apoptosis, it potentiated TNF-induced necrosis. Cotreatment with TNF and zVAD was characterized by ATP depletion and accelerated necrosis. To investigate the mechanisms underlying TNF-induced cell death and its potentiation by zVAD, we examined the role of poly(ADP-ribose)polymerase-1 (PARP-1). TNF but not CD95 mediated PARP activation, whereas a PARP inhibitor suppressed TNF-induced necrosis and the sensitizing effect of zVAD. In addition, fibroblasts expressing a noncleavable PARP-1 mutant were more sensitive to TNF than wild-type cells. Our results indicate that TNF induces PARP activation leading to ATP depletion and subsequent necrosis. In contrast, in CD95-mediated apoptosis caspases cause PARP-1 cleavage and thereby maintain ATP levels. Because ATP is required for apoptosis, we suggest that PARP-1 cleavage functions as a molecular switch between apoptotic and necrotic modes of death receptor-induced cell death.

Time trends incidence of both major histologic types of esophageal carcinomas in selected countries, 1973-1995.

Abstract: The purpose of our study was to examine the incidence patterns of 2 major histologic types of esophageal cancer, in selected countries world-wide and to identify components of birth cohort, period and age as determinants of observed time trends using regression modeling. The roles of temporal changes in specification of histology of tumors and of classification of cancers at the gastroesophageal junction as esophageal or gastric in origin were taken into consideration. In all, 56,426 esophageal cancer cases were included. The results indicate that the incidence rate of squamous cell carcinoma of the esophagus has been relatively stable in most of the countries analyzed, although increasing trends were observed in Denmark and the Netherlands (Eindhoven) among men and in Canada, Scotland and Switzerland among women. There was a significant increase in the incidence of esophageal adenocarcinomas in both sexes in the United States (among whites and blacks), Canada and South Australia and in 6 European countries (Scotland, Denmark, Iceland, Finland, Sweden and Norway). In France the increase was limited to men and in Switzerland the increase was observed only in women. Modeling was unable to distinguish which trends were the results of changes in risk between generations (as cohort effects), or changes in all age groups simultaneously (as a period effect).

Glycemic index in chronic disease: a review

Abstract: Aim: The intent of this review is to critically analyze the scientific evidence on the role of the glycemic index in chronic Western disease and to discuss the utility of the glycemic index in the prevention and management of these disease states. Background: The glycemic index ranks foods based on their postprandial blood glucose response. Hyperinsulinemia and insulin resistance, as well as their determinants (eg high energy intake, obesity, lack of physical activity) have been implicated in the etiology of diabetes, coronary heart disease and cancer. Recently, among dietary factors, carbohydrates have attracted much attention as a significant culprit, however, different types of carbohydrate produce varying glycemic and insulinemic responses. Low glycemic index foods, characterized by slowly absorbed carbohydrates, have been shown in some studies to produce beneficial effects on glucose control, hyperinsulinemia, insulin resistance, blood lipids and satiety. Method: Studies on the short and long-term metabolic effects of diets with different glycemic indices will be presented and discussed. The review will focus primarily on clinical and epidemiological data, and will briefly discuss in vitro and animal studies related to possible mechanisms by which the glycemic index may influence chronic disease. European Journal of Clinical Nutrition (2002) 56, 1049 ‐ 1071. doi:10.1038/sj.ejcn.1601454

Herpes Simplex Virus-2 as a Human Papillomavirus Cofactor in the Etiology of Invasive Cervical Cancer

Abstract: Background Human papillomavirus (HPV) infection is the main cause of invasive cervical cancer, but cofactors may act in conjunction with HPV. We performed a pooled analysis of seven case-control studies to examine the effect of one possible HPV cofactor, herpes simplex virus-2 (HSV-2) infection, in the etiology of invasive cervical cancer. Methods Blood and exfoliated cervical specimens were obtained from 1263 case patients with invasive cervical cancer (1158 with squamous-cell carcinomas and 105 with adeno- or adenosquamous-cell carcinomas) and 1117 age-matched control subjects. Western blot analysis and/or an enzyme-linked immunosorbent assay were used to detect type-specific serum antibodies to HSV-2 and HSV-1, and Chlamydia trachomatis serum antibodies were detected using a micro-immunofluorescence assay. HPV DNA was detected using a polymerase chain reaction assay. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were computed from unconditional logistic regression models. Results Overall, HSV-2 seropositivity was higher among case patients with squamous-cell carcinoma (44.4%, 95% CI = 41.5% to 47.3%) or adeno- or adenosquamous-cell carcinoma (43.8%, 95% CI = 34.2% to 53.5%) than among control subjects (25.6%, 95% CI = 23.0% to 28.2%). Cervical specimens from 1098 (94.8%) squamous-cell carcinoma case patients, 95 (90.5%) adeno- or adenosquamous carcinoma case patients, and 164 (14.7%) control subjects were positive for HPV DNA. Among the HPV DNA-positive women, HSV-2 seropositivity was associated with increased risks of squamous-cell carcinoma (OR = 2.19, 95% CI = 1.41 to 3.40) and adeno- or adenosquamous-cell carcinoma (OR = 3.37, 95% CI = 1.47 to 7.74) after adjustment for potential confounders. A similar association between HSV-2 seropositivity and squamous-cell carcinoma risk was observed after further controlling for markers of sexual behavior (OR = 1.96, 95% CI = 1.24 to 3.09). Among control subjects, HSV-2 seropositivity was associated with markers of sexual behavior, but not with cervical HPV DNA positivity. Conclusion HSV-2 infection may act in conjunction with HPV infection to increase the risk of invasive cervical carcinoma.

European Prospective Investigation into Cancer and Nutrition (EPIC) calibration study: rationale, design and population characteristics

Abstract: The European Prospective Investigation into Cancer and Nutrition (EPIC), which covers a large cohort of half a million men and women from 23 European centres in 10 Western European countries, was designed to study the relationship between diet and the risk of chronic diseases, particularly cancer Information on usual individual dietary intake was assessed using different validated dietary assessment methods across participating countries In order to adjust for possible systematic over- or underestimation in dietary intake measurements and correct for attenuation bias in relative risk estimates, a calibration approach was developed This approach involved an additional dietary assessment common across study populations to re-express individual dietary intakes according to the same reference scale A single 24-hour diet recall was therefore collected, as the EPIC reference calibration method, from a stratified random sample of 36 900 subjects from the entire EPIC cohort, using a software program (EPIC-SOFT) specifically designed to standardise the dietary measurements across study populations This paper describes the design and populations of the calibration sub-studies set up in the EPIC centres In addition, to assess whether the calibration sub-samples were representative of the entire group of EPIC cohorts, a series of subjects' characteristics known possibly to influence dietary intakes was compared in both population groups This was the first time that calibration sub-studies had been set up in a large multi-centre European study These studies showed that, despite certain inherent methodological and logistic constraints, a study design such as this one works relatively well in practice The average response in the calibration study was 783% and ranged from 465% to 925% The calibration population differed slightly from the overall cohort but the differences were small for most characteristics and centres The overall results suggest that, after adjustment for age, dietary intakes estimated from calibration samples can reasonably be interpreted as representative of the main cohorts in most of the EPIC centres

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.

Oral cancer in Southern India: The influence of smoking, drinking, paan-chewing and oral hygiene

Abstract: Between 1996 and 1999 we carried out a case-control study in 3 areas in Southern India (Bangalore, Madras and Trivandrum) including 591 incident cases of cancer of the oral cavity (282 women) and 582 hospital controls (290 women), frequency-matched with cases by age and gender. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from unconditional multiple logistic regressions and adjusted for age, gender, center, education, chewing habit and (men only) smoking and drinking habits. Low educational attainment, occupation as a farmer or manual worker and various indicators of poor oral hygiene were associated with significantly increased risk. An OR of 2.5 (95% CI 1.4-4.4) was found in men for smoking > or = 20 bidi or equivalents versus 0/day. The OR for alcohol drinking was 2.2 (95% CI 1.4-3.3). The OR for paan chewing was more elevated among women (OR 42; 95% CI 24-76) than among men (OR 5.1; 95% CI 3.4-7.8). A similar OR was found among chewers of paan with (OR 6.1 in men and 46 in women) and without tobacco (OR 4.2 in men and 16.4 in women). Among men, 35% of oral cancer is attributable to the combination of smoking and alcohol drinking and 49% to pan-tobacco chewing. Among women, chewing and poor oral hygiene explained 95% of oral cancer.

Validation and calibration of food-frequency questionnaire measurements in the Northern Sweden Health and Disease cohort

Abstract: OBJECTIVES: To evaluate the reproducibility of, and to compare and calibrate, diet measures by the Northern Sweden 84-item food-frequency questionnaire (FFQ) with measures from 24-hour diet recalls ...

Weight control and physical activity in cancer prevention.

Abstract: Overweight and obesity have reached epidemic dimensions worldwide, mainly due to consumption of high energy diets and increased sedentary behaviour. Overweight and insufficient physical activity are clearly associated with cardiovascular diseases and type 2 diabetes. Evidence is also accumulating that they may also increase cancer risk, particularly in the colon, breast and endometrium. This effect seems to be mediated by alterations in the metabolism of endogenous hormones, including sex steroids and insulin, and levels of insulin-like growth factor(IGF)-I and IGF-binding proteins. In light of the beneficial effects of weight control and physical activity for cancer prevention, a healthy lifestyle, keeping a low body weight and exercising most days of the week, is recommended.

N‐3 and N‐6 fatty acids in breast adipose tissue and relative risk of breast cancer in a case‐control study in Tours, France

Abstract: Experimental studies have indicated that n-3 fatty acids, including alpha-linolenic acid (18:3 n-3) and long-chain n-3 polyunsaturated fatty acids inhibit mammary tumor growth and metastasis. Earlier epidemiological studies have given inconclusive results about a potential protective effect of dietary n-3 polyunsaturated fatty acids on breast cancer risk, possibly because of methodological issues inherent to nutritional epidemiology. To evaluate the hypothesis that n-3 fatty acids protect against breast cancer, we examined the fatty acid composition in adipose tissue from 241 patients with invasive, nonmetastatic breast carcinoma and from 88 patients with benign breast disease, in a case-control study in Tours, central France. Fatty acid composition in breast adipose tissue was used as a qualitative biomarker of past dietary intake of fatty acids. Biopsies of adipose tissue were obtained at the time of surgery. Individual fatty acids were measured as a percentage of total fatty acids, using capillary gas chromatography. Unconditional logistic regression modeling was used to obtain odds ratio estimates while adjusting for age, height, menopausal status and body mass index. We found inverse associations between breast cancer-risk and n-3 fatty acid levels in breast adipose tissue. Women in the highest tertile of alpha-linolenic acid (18:3 n-3) had an odds ratio of 0.39 (95% confidence intervals [CI] = 0.19–0.78) compared to women in the lowest tertile (trend p = 0.01). In a similar way, women in the highest tertile of docosahexaenoic acid (22:6 n-3) had an odds ratio of 0.31 (95% CI = 0.13-0.75) compared to women in the lowest tertile (trend p = 0.016). Women in the highest tertile of the long-chain n-3/total n-6 ratio had an odds ratio of 0.33 (95% confidence interval = 0.17–0.66) compared to women in the lowest tertile (trend p = 0.0002). In conclusion, our data based on fatty acids levels in breast adipose tissue suggest a protective effect of n-3 fatty acids on breast cancer risk and support the hypothesis that the balance between n-3 and n-6 fatty acids plays a role in breast cancer. © 2001 Wiley-Liss, Inc.

Prevalence and determinants of HPV infection among Colombian women with normal cytology

Abstract: Human papillomavirus is the principal risk factor associated with cervical cancer, the most common malignancy among women in Colombia. We conducted a survey, aiming to report type specific prevalence and determinants of human papillomavirus infection in women with normal cytology. A total of 1859 women from Bogota, Colombia were interviewed and tested for human papillomavirus using a general primer GP5+/GP6+ mediated PCR–EIA. The overall HPV DNA prevalence was 14.8%; 9% of the women were infected by high risk types, 3.1% by low risk types, 2.3% by both high risk/low risk types and 0.4% by uncharacterized types (human papillomavirus X). Thirty-two different human papillomavirus types were detected, being human papillomavirus 16, 58, 56, 81(CP8304) and 18 the most common types. The human papillomavirus prevalence was 26.1% among women younger than 20 years, 2.3% in women aged 45–54 years, and 13.2% in women aged 55 years or more. For low risk types the highest peak of prevalence was observed in women aged 55 years or more. Compared to women aged 35–44 years, women aged less than 20 years had a 10-fold increased risk of having multiple infections. Besides age, there was a positive association between the risk of human papillomavirus infection and number of regular sexual partners and oral contraceptive use. In women aged below 25 years, high educational level and having had casual sexual partners predicted infection risk. In conclusion, there was a broad diversity of human papillomavirus infections with high risk types being the most common types detected. In this population multiplicity of sexual partners and, among young women, high educational level and casual sexual partners seem to determine risk. British Journal of Cancer (2002) 87, 324–333. doi:10.1038/sj.bjc.6600442 www.bjcancer.com © 2002 Cancer Research UK

Variability of fish consumption within the 10 European countries participating in the European Investigation into Cancer and Nutrition (EPIC) study

Abstract: OBJECTIVE: To describe and compare the consumption of total fish (marine foods) and the fish sub-groups - white fish, fatty fish, very fatty fish, fish products and crustacea, in participants from the European Investigation into Cancer and Nutrition (EPIC) study. DESIGN: Cross-sectional analysis of dietary intake using a computerised standardised 24-hour recall interview. Crude means, means and standard errors adjusted by age, season and day of the week were calculated, stratified by centre and gender. SETTING: Twenty-seven redefined centres in the 10 European countries participating in the EPIC study. SUBJECTS: In total, 35 955 subjects (13 031 men and 22 924 women), aged 35-74 years, selected from the main EPIC cohort. RESULTS: A six- to sevenfold variation in total fish consumption exists in women and men, between the lowest consumption in Germany and the highest in Spain. Overall, white fish represented 49% and 45% of the intake of total fish in women and men, respectively, with the greatest consumption in centres in Spain and Greece and the least in the German and Dutch centres. Consumption of fatty fish reflected that of total fish. However, the greatest intake of very fatty fish was in the coastal areas of northern Europe (Denmark, Sweden and Norway) and in Germany. Consumption of fish products was greater in northern than in southern Europe, with white fish products predominating in centres in France, Italy, Spain, The Netherlands and Norway. Intake of roe and roe products was low. The highest consumption of crustacea was found in the French, Spanish and Italian centres. The number of fish types consumed was greater in southern than in northern Europe. The greatest variability in consumption by day of the week was found in the countries with the lowest fish intake. CONCLUSIONS: Throughout Europe, substantial geographic variation exists in total fish intake, fish sub-groups and the number of types consumed. Day-to-day variability in consumption is also high.

Combined effect of tobacco and alcohol on laryngeal cancer risk: A case-control study

Abstract: Objective: To provide information on the effects of alcohol and tobacco on laryngeal cancer and its subsites. Methods: This was a case–control study conducted between 1992 and 2000 in northern Italy and Switzerland. A total of 527 cases of incident squamous-cell carcinoma of the larynx and 1297 hospital controls frequency-matched with cases on age, sex, and area of residence were included. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using multiple logistic regression. Results: In comparison with never smokers, ORs were 19.8 for current smokers and 7.0 for ex-smokers. The risk increased in relation to the number of cigarettes (OR = 42.9 for ≥25 cigarettes/day) and for duration of smoking (OR = 37.2 for ≥40 years). For alcohol, the risk increased in relation to number of drinks (OR = 5.9 for ≥56 drinks per week). Combined alcohol and tobacco consumption showed a multiplicative (OR = 177) rather than an additive risk. For current smokers and current drinkers the risk was higher for supraglottis (ORs 54.9 and 2.6, respectively) than for glottis (ORs 7.4 and 1.8) and others subsites (ORs 10.9 and 1.9). Conclusions: Our study shows that both cigarette smoking and alcohol drinking are independent risk factors for laryngeal cancer. Heavy consumption of alcohol and cigarettes determined a multiplicative risk increase, possibly suggesting biological synergy.