Summary Background Infections with certain viruses, bacteria, and parasites are strong risk factors for specific cancers. As new cancer statistics and epidemiological findings have accumulated in the ...past 5 years, we aimed to assess the causal involvement of the main carcinogenic agents in different cancer types for the year 2012. Methods We considered ten infectious agents classified as carcinogenic to human beings by the International Agency for Research on Cancer. We calculated the number of new cancer cases in 2012 attributable to infections by country, by combining cancer incidence estimates (from GLOBOCAN 2012) with estimates of attributable fraction (AF) for the infectious agents. AF estimates were calculated from the prevalence of infection in cancer cases and the relative risk for the infection (for some sites). Estimates of infection prevalence, relative risk, and corresponding 95% CIs for AF were obtained from systematic reviews and pooled analyses. Findings Of 14 million new cancer cases in 2012, 2·2 million (15·4%) were attributable to carcinogenic infections. The most important infectious agents worldwide were Helicobacter pylori (770 000 cases), human papillomavirus (640 000), hepatitis B virus (420 000), hepatitis C virus (170 000), and Epstein-Barr virus (120 000). Kaposi's sarcoma was the second largest contributor to the cancer burden in sub-Saharan Africa. The AFs for infection varied by country and development status—from less than 5% in the USA, Canada, Australia, New Zealand, and some countries in western and northern Europe to more than 50% in some countries in sub-Saharan Africa. Interpretation A large potential exists for reducing the burden of cancer caused by infections. Socioeconomic development is associated with a decrease in infection-associated cancers; however, to reduce the incidence of these cancers without delay, population-based vaccination and screen-and-treat programmes should be made accessible and available. Funding Fondation de France.
Summary Background Intrauterine device (IUD) use has been shown to reduce the risk of endometrial cancer, but little is known about its association with cervical cancer risk. We assessed whether IUD ...use affects cervical human papillomavirus (HPV) infection and the risk of developing cervical cancer. Methods We did a pooled analysis of individual data from two large studies by the International Agency for Research on Cancer and Institut Català d'Oncologia research programme on HPV and cervical cancer; one study included data from ten case–control studies of cervical cancer done in eight countries, and the other included data from 16 HPV prevalence surveys of women from the general population in 14 countries. 2205 women with cervical cancer and 2214 matched control women without cervical cancer were included from the case–control studies, and 15 272 healthy women from the HPV surveys. Information on IUD use was obtained by personal interview. HPV DNA was tested by PCR-based assays. Odds ratios and 95% CIs were estimated using multivariate unconditional logistic regression for the associations between IUD use, cervical HPV DNA, and cervical cancer. Findings After adjusting for relevant covariates, including cervical HPV DNA and number of previous Papanicolaou smears, a strong inverse association was found between ever use of IUDs and cervical cancer (odds ratio 0·55, 95% CI 0·42–0·70; p<0·0001). A protective association was noted for squamous-cell carcinoma (0·56, 0·43–0·72; p<0·0001), adenocarcinoma and adenosquamous carcinoma (0·46, 0·22–0·97; p=0·035), but not among HPV-positive women (0·68, 0·44–1·06; p=0·11). No association was found between IUD use and detection of cervical HPV DNA among women without cervical cancer. Interpretation Our data suggest that IUD use might act as a protective cofactor in cervical carcinogenesis. Cellular immunity triggered by the device might be one of several mechanisms that could explain our findings. Funding Instituto de Salud Carlos III; Agència de Gestió d'Ajuts Universitaris i Recerca; Marató TV3 Foundation; Bill & Melinda Gates Foundation; International Agency for Research on Cancer; European Community; Fondo de Investigaciones Sanitarias, Spain; Preventiefonds, Netherlands; Programa Interministerial de Investigación y Desarrollo, Spain; Conselho Nacional de Desenvolvimiento Cientifico e Tecnologico, Brazil; and Department of Reproductive Health & Research, WHO.
Summary Background Infections with certain viruses, bacteria, and parasites have been identified as strong risk factors for specific cancers. An update of their respective contribution to the global ...burden of cancer is warranted. Methods We considered infectious agents classified as carcinogenic to humans by the International Agency for Research on Cancer. We calculated their population attributable fraction worldwide and in eight geographical regions, using statistics on estimated cancer incidence in 2008. When associations were very strong, calculations were based on the prevalence of infection in cancer cases rather than in the general population. Estimates of infection prevalence and relative risk were extracted from published data. Findings Of the 12·7 million new cancer cases that occurred in 2008, the population attributable fraction (PAF) for infectious agents was 16·1%, meaning that around 2 million new cancer cases were attributable to infections. This fraction was higher in less developed countries (22·9%) than in more developed countries (7·4%), and varied from 3·3% in Australia and New Zealand to 32·7% in sub-Saharan Africa. Helicobacter pylori , hepatitis B and C viruses, and human papillomaviruses were responsible for 1·9 million cases, mainly gastric, liver, and cervix uteri cancers. In women, cervix uteri cancer accounted for about half of the infection-related burden of cancer; in men, liver and gastric cancers accounted for more than 80%. Around 30% of infection-attributable cases occur in people younger than 50 years. Interpretation Around 2 million cancer cases each year are caused by infectious agents. Application of existing public health methods for infection prevention, such as vaccination, safer injection practice, or antimicrobial treatments, could have a substantial effect on the future burden of cancer worldwide. Funding Fondation Innovations en Infectiologie (FINOVI) and the Bill & Melinda Gates Foundation (BMGF).
Human papillomavirus and cervical cancer Crosbie, Emma J, PhD; Einstein, Mark H, MD; Franceschi, Silvia, MD ...
The Lancet (British edition),
09/2013, Letnik:
382, Številka:
9895
Journal Article
Recenzirano
Summary Cervical cancer is caused by human papillomavirus infection. Most human papillomavirus infection is harmless and clears spontaneously but persistent infection with high-risk human ...papillomavirus (especially type 16) can cause cancer of the cervix, vulva, vagina, anus, penis, and oropharynx. The virus exclusively infects epithelium and produces new viral particles only in fully mature epithelial cells. Human papillomavirus disrupts normal cell-cycle control, promoting uncontrolled cell division and the accumulation of genetic damage. Two effective prophylactic vaccines composed of human papillomavirus type 16 and 18, and human papillomavirus type 16, 18, 6, and 11 virus-like particles have been introduced in many developed countries as a primary prevention strategy. Human papillomavirus testing is clinically valuable for secondary prevention in triaging low-grade cytology and as a test of cure after treatment. More sensitive than cytology, primary screening by human papillomavirus testing could enable screening intervals to be extended. If these prevention strategies can be implemented in developing countries, many thousands of lives could be saved.
Summary Background Cervical cancer incidence remains high in several Baltic, central, and eastern European (BCEE) countries, mainly as a result of a historical absence of effective screening ...programmes. As a catalyst for action, we aimed to estimate the number of women who could be spared from cervical cancer across six countries in the region during the next 25 years, if effective screening interventions were introduced. Methods In this population-based study, we applied age–period–cohort models with spline functions within a Bayesian framework to incidence data from six BCEE countries (Estonia, Latvia, Lithuania, Belarus, Bulgaria, and Russia) to develop projections of the future number of new cases of cervical cancer from 2017 to 2040 based on two future scenarios: continued absence of screening (scenario A) versus the introduction of effective screening from 2017 onwards (scenario B). The timespan of available data varied from 16 years in Bulgaria to 40 years in Estonia. Projected rates up to 2040 were obtained in scenario A by extrapolating cohort-specific trends, a marker of changing risk of human papillomavirus (HPV) infection, assuming a continued absence of effective screening in future years. Scenario B added the effect of gradual introduction of screening in each country, under the assumption period effects would be equivalent to the decreasing trend by calendar year seen in Denmark (our comparator country) since the progressive regional introduction of screening from the late 1960s. Findings According to scenario A, projected incidence rates will continue to increase substantially in many BCEE countries. Very high age-standardised rates of cervical cancer are predicted in Lithuania, Latvia, Belarus, and Estonia (up to 88 cases per 100 000). According to scenario B, the beneficial effects of effective screening will increase progressively over time, leading to a 50–60% reduction of the projected incidence rates by around 2040, resulting in the prevention of cervical cancer in 1500 women in Estonia and more than 150 000 women in Russia. The immediate launch of effective screening programmes could prevent almost 180 000 new cervical cancer diagnoses in a 25-year period in the six BCEE countries studied. Interpretation Based on our findings, there is a clear need to begin cervical screening in these six countries as soon as possible to reduce the high and increasing incidence of cervical cancer over the next decades. Funding None.
Summary Background Controversy remains over whether high-risk human papillomavirus (HPV) DNA testing should be used as a primary screen for cervical cancer. The aims of our study were to assess ...whether HPV DNA testing could be applied to cervical-cancer screening programmes in China, as well as other similar developing countries. Methods We did a pooled analysis of population-based cervical cancer screening studies done in mainland China from 1999 to 2008 with concurrent HPV DNA testing (Hybrid Capture 2 assay; Qiagen, Gaithersburg, MD, USA), liquid-based cytology (LBC), and visual inspection with acetic acid (VIA). Eligible women were sexually active, not pregnant, had an intact uterus, and had no history of cervical intraepithelial neoplasia (CIN), cervical cancer, or pelvic irradiation. All women positive for any test were referred for colposcopy and biopsy. Cervical lesions were diagnosed by directed or random biopsy. We assessed the diagnostic accuracy of HPV DNA testing for the detection of CIN grade 3 or greater. Findings 30 371 women from 17 cross-sectional, population-based studies in various parts of China were screened. 1523 women were subsequently excluded because of inadequate HPV DNA specimens or they did not have a biopsy taken, which included women with atypical squamous cells of undetermined significance; low-grade squamous intraepithelial lesion or worse; positive HPV, negative cytology, and missing or positive colposcopy results; and unsatisfactory cytology results. HPV DNA testing had a higher sensitivity of 97·5% (95% CI 95·7–98·7) for detection of CIN grade 3 or worse, and a lower specificity of 85·1% (82·3–87·9), compared with cytology (sensitivity 87·9% 95% CI 84·7–90·7, specificity 94·7% 93·5–96·0) and VIA (54·6% 48·0–61·2, 89·9% 86·8–93·0). Sensitivity did not vary by study or age (<35 years, 35–49 years, ≥50 years); however, specificity did vary with age (p<0·0001) and was highest in women younger than 35 years (89·4%; 95% CI 86·1–91·5). An increase in the positive cutoff point from the manufacturer recommended 1 pg/mL to 2 pg/mL led to a decrease in the overall HPV DNA positivity from 16·3% to 13·9% (p<0·0001), which could result in a decrease in referral rates, although sensitivity was slightly lower (97·5% to 95·2%). An increase in the cutoff point to 10 pg/mL in women younger than 35 years maintained a high sensitivity 97·7% (95% CI 87·7–99·9) and increased specificity to 93·5% (95% CI 91·9–94·6). Interpretation HPV DNA testing is highly sensitive and moderately specific for CIN grade 3 or worse, with consistent results across study sites and age groups—including women younger than 35 years. A rise in the cutoff point might be beneficial for future screening programmes in China, especially when screening women younger than 35 years. Funding Fogarty International Clinical Research Scholars Program (Fogarty International Center, US National Institutes of Health, through the International Clinical Research Fellows Program at Vanderbilt University); Academic Capacity Development Program of the Beijing Municipal Commission of Education; and Cancer Institute and Hospital of the Chinese Academy of Medical Sciences.
Abstract Purpose Few data are available on the role of combinations of foods and/or nutrients on pancreatic cancer risk. To add further information on dietary patterns potentially associated to ...pancreatic cancer, we applied an exploratory principal component factor analysis on 28 major nutrients derived from an Italian case-control study. Methods Cases were 326 incident pancreatic cancer cases and controls 652 frequency-matched controls admitted to hospital for non-neoplastic diseases. Dietary information was collected through a validated and reproducible food frequency questionnaire. Multiple logistic regression models adjusted for sociodemographic variables and major recognized risk factors for pancreatic cancer were used to estimate the odds ratios (OR) of pancreatic cancer for each dietary pattern. Results We identified four dietary patterns—named “animal products,” “unsaturated fats,” “vitamins and fiber,” and “starch rich,” that explain 75% of the total variance in nutrient intake in this population. After allowing for all the four patterns, positive associations were found for the animal products and the starch rich patterns, the OR for the highest versus the lowest quartiles being 2.03 (95% confidence interval CI, 1.29–3.19) and 1.69 (95% CI, 1.02–2.79), respectively; an inverse association emerged for the vitamins and fiber pattern (OR, 0.55; 95% CI, 0.35–0.86), whereas no association was observed for the unsaturated fats pattern (OR, 1.13; 95% CI, 0.71–1.78). Conclusions A diet characterized by a high consumption of meat and other animal products, as well as of (refined) cereals and sugars, is positively associated with pancreatic cancer risk, whereas a diet rich in fruit and vegetables is inversely associated.
Abstract Purpose Poorer survival from head and neck squamous cell carcinoma (HNSCC) in African Americans (AA) may be due to disparity in the prevalence of Human Papillomavirus (HPV) but earlier ...studies often failed to control other etiological factors. We aimed to elucidate whether racial disparities in HPV prevalence and overall survival were due to confounding from smoking or alcohol use. Materials and methods 385 patients with SCC of the mouth, pharynx, nose, or larynx who had surgical resection at Wayne State University affiliated hospitals were identified through a population-based cancer registry. Formalin fixed paraffin embedded tissue blocks were used to determine the presence of HPV DNA and its genotype using a sensitive broad-spectrum PCR technique. Patients’ demographics, tumor characteristics and vital status were obtained through record linkage with the registry data and smoking and alcohol information was abstracted from medical record. Cox’s proportional hazard model and unconditional logistic regression models were employed to analyze the overall survival and tumor HPV-positivity, respectively. Results HPV positivity in oropharyngeal cancer was substantially lower in AA than in other racial groups (odds ratio 0.14, 95% confidence interval (CI) 0.05–0.37) and adjustment for smoking or alcohol did not change this association. However, a significantly increased hazard ratio of death in AA oropharyngeal cancer patients (univariable hazard ratio (HR) 2.55, 95% CI 1.42–4.59) decreased to almost unity (HR 1.49, 95% CI 0.75–2.93) after adjustment for HPV and smoking. Conclusions Lower HPV prevalence in AA largely accounts for their poorer survival from oropharyngeal cancer, but not other HNSSC.
Objective Although several studies have been conducted on the relation between dietary habits and endometrial cancer risk, the evidence for specific food groups is still controversial. Study Design ...We analyzed data from an Italian case-control study including 454 women with histologically confirmed endometrial cancer and 908 controls admitted to the same hospitals for acute, nonneoplastic conditions. Multivariate odds ratios (ORs) were obtained after allowance for major potential confounding factors. Results A significant increase in risk was observed for red meat, with an OR of 2.07 for an increment of 1 serving per day. Inverse associations were observed for coffee (OR, 0.83), cereals (OR, 0.92), and vegetables (OR, 0.83). Conclusion Our results support the existence of a relation between dietary habits and endometrial cancer risk and in particular suggest that a diet rich in red meat and poor in vegetables may have an unfavorable effect.
Objective Several factors that are related to ovulation are relevant to ovarian cancer risk, but it is unclear whether they can be included in a single definition of years of ovulation. Study design ...We considered data from 2 case-control studies of ovarian cancer that were conducted in Italy and included 1822 histologically confirmed cases and 4631 control subjects who were hospitalized for acute conditions. Results As compared with the lowest quartile, the odds ratios of ovarian cancer were 1.60 (95% CI, 1.31-1.95), 1.65 (95% CI, 1.34-2.03), and 1.81 (95% CI, 1.47-2.23) for increasing quartiles of lifetime ovulatory cycles. For 1 year of ovulation avoided, the continuous odds ratios were 0.975 (95% CI, 0.965-0.985) for total ovulatory cycles, 0.91 (95% CI, 0.87-0.95) for parity-related anovulations, 0.90 (95% CI, 0.76-1.06) for abortions, 0.92 (95% CI, 0.87-0.97) for oral contraceptive use, 0.99 (95% CI, 0.96-1.03) for age at menarche, and 0.97 (95% CI, 0.95-0.98) for age at menopause. Women who reported high numbers of ovulatory cycles and family history of ovarian/breast cancers had an odds ratio of 3.27 (95% CI, 2.44-4.36). Conclusion This study found that pregnancy and oral contraceptive use had a stronger protective effect on ovarian cancer than other anovulatory factors.
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