Cancers in Australia in 2010 attributable to infectious agents

Cancers Attributable to Infections in the US in 2017: A Meta-Analysis

Importance

Infections are largely modifiable causes of cancer. However, there remains untapped potential for preventing and treating carcinogenic infections in the US.

Objective

To estimate the percentage and number of incident cancers attributable to infections in the US among adults and children for the most recent year cancer incidence data were available (2017).

Data Sources

A literature search from 1946 onward was performed in MEDLINE on January 6, 2023, to obtain the data required to calculate population attributable fractions for 31 infection-cancer pairs. National Health and Nutrition Examination Survey data were used to estimate the population prevalence of hepatitis B and C viruses and Helicobacter pylori.

Study Selection

Studies conducted in the US or other Western countries were selected according to specific infection-cancer criteria.

Data Extraction and Synthesis

Data from 128 studies were meta-analyzed to obtain the magnitude of an infection-cancer association or prevalence of the infection within cancer cells.

Main Outcomes and Measures

The proportion of cancer incidence attributable to 8 infections.

Results

Of the 1 666 102 cancers diagnosed in 2017 among individuals aged 20 years or older in the US, 71 485 (4.3%; 95% CI, 3.1%-5.3%) were attributable to infections. Human papillomavirus (n = 38 230) was responsible for the most cancers, followed by H pylori (n = 10 624), hepatitis C virus (n = 9006), Epstein-Barr virus (n = 7581), hepatitis B virus (n = 2310), Merkel cell polyomavirus (n = 2000), Kaposi sarcoma-associated herpesvirus (n = 1075), and human T-cell lymphotropic virus type 1 (n = 659). Cancers with the most infection-attributable cases were cervical (human papillomavirus; n = 12 829), gastric (H pylori and Epstein-Barr virus; n = 12 565), oropharynx (human papillomavirus; n = 12 430), and hepatocellular carcinoma (hepatitis B and C viruses; n = 10 017). The burden of infection-attributable cancers as a proportion of total cancer incidence ranged from 9.6% (95% CI, 9.2%-10.0%) for women aged 20 to 34 years to 3.2% (95% CI, 2.4%-3.8%) for women aged 65 years or older and from 6.1% (95% CI, 5.2%-7.0%) for men aged 20 to 34 years to 3.3% (95% CI, 1.9%-4.4%) for men aged 65 years or older. Among those aged 19 years or younger, 2.2% (95% CI, 1.3%-3.0%) of cancers diagnosed in 2017 were attributable to Epstein-Barr virus.

Conclusions and Relevance

Infections were estimated to be responsible for 4.3% of cancers diagnosed among adults in the US in 2017 and, therefore, represent an important target for cancer prevention efforts.

Self-reported HPV vaccination and vaccination record linkage in the Australian Oral Diversity Study

PURPOSE

Australia has a school-based human papillomavirus (HPV) vaccination scheme that was implemented for girls in 2007 and for boys in 2013. HPV vaccination status is important for many studies into HPV infection. Here we wanted to estimate the validity of self-reported HPV vaccination status by comparing self-report to data from the national vaccination register.

METHODS

Australian residents aged 18-70 years were recruited for the Oral Diversity Study from October 2020 to November 2021. Participants were asked to provide consent for record linkage to the Australian Immunisation Register (AIR). They were also asked to fill out a questionnaire about HPV vaccination, lifestyle, and sexual behavior.

RESULTS

1,023 participants were recruited, permission was received from 911 participants for HPV vaccination record linkage, and 850 self-reported vaccination and were part of the validity analysis. Of those 233 (26%) were confirmed to be HPV vaccinated. Ninety-one percent of the vaccinated were females (n = 212), 19 males and two non-binary. The highest HPV vaccine uptake was seen in the youngest age group (18-29 years; 80%), followed by 66% in 30-39 year olds, 2% in 40-49 year olds and then dropped significantly to 0.7% for people 50-70 years old. The sensitivity of self-report was 99.0%, and the specificity 94.5%, and the positive predictive value was 85.7% and the negative predictive value 99.7%.

CONCLUSION

We found that the correlation between self-reported Gardasil® vaccination and the AIR records were very good, with high sensitivity and specificity.

Performance of p16/Ki67 Immunostaining for Triage of Elderly Women with Atypical Squamous Cells of Undetermined Significance

BACKGROUND

The p16/Ki67 technique has been poorly studied in postmenopausal women with ASC-US cytology. The objective of this study was to compare the accuracy of p16/Ki67 staining, HPV testing and HPV 16 genotyping for the identification of CIN2 + lesions in postmenopausal women with ASC-US cytology.

METHOD

A total of 324 postmenopausal women with positive ASC-US were included. The women underwent HPV test, colposcopy, and biopsy. The slides were discolored and then stained with the CINtec Plus Kit for p16/Ki67. The HPV test results were classified as HPV16 +, hrHPV+ (other hrHPV genotypes), or HPV negative.

RESULTS

The p16/Ki67 sensitivity for CIN2+ was 94.5%, the specificity 86.6%, PPV of 59% and NPV of 95.9%. The HPV test showed a sensitivity of 96.4% for CIN2+, a specificity of 62.8%, a PPV of 35% and a NPV of 98.8%. In postmenopausal women, the prevalence of genotype 16 decreases in favor of the other high-risk genotypes.

CONCLUSION

Given the low sensitivity of cytology and the low percentage of HPV16-positive cancers among elderly women, triage via cytology and genotyping is not the best strategy; double staining cytology shows high profiles of sensibility and specificity for CIN2+ in ASCUS postmenopausal women.

The future burden of oesophageal and stomach cancers attributable to modifiable behaviours in Australia: a pooled cohort study

BACKGROUND

We quantified the individual and joint contribution of contemporaneous causal behavioural exposures on the future burden of oesophageal and stomach cancers and their subtypes and assessed whether these burdens differ between population groups in Australia, as such estimates are currently lacking.

METHODS

We combined hazard ratios from seven pooled Australian cohorts (N = 367,058) linked to national cancer and death registries with exposure prevalence from the 2017-2018 National Health Survey to estimate Population Attributable Fractions (PAFs) with 95% confidence intervals (CIs), accounting for competing risk of death.

RESULTS

Current and past smoking explain 35.2% (95% CI = 11.7-52.4%), current alcohol consumption exceeding three drinks/day 15.7% (95% CI = 0.9-28.4%), and these exposures jointly 41.4% (95% CI = 19.8-57.3%) of oesophageal squamous cell carcinomas in Australia. Current and past smoking contribute 38.2% (95% CI = 9.4-57.9%), obesity 27.0% (95% CI = 0.6-46.4%), and these exposures jointly 54.4% (95% CI = 25.3-72.1%) of oesophageal adenocarcinomas. Overweight and obesity explain 36.1% (95% CI = 9.1-55.1%), current and past smoking 24.2% (95% CI = 4.2-40.0%), and these exposures jointly 51.2% (95% CI = 26.3-67.8%) of stomach cardia cancers. Several population groups had a significantly higher smoking-attributable oesophageal cancer burden, including men and those consuming excessive alcohol.

CONCLUSIONS

Smoking is the leading preventable behavioural cause of oesophageal cancers and overweight/obesity of stomach cancers.

KSHV (HHV8) vaccine: promises and potential pitfalls for a new anti-cancer vaccine

Seven viruses cause at least 15% of the total cancer burden. Viral cancers have been described as the "low-hanging fruit" that can be potentially prevented or treated by new vaccines that would alter the course of global human cancer. Kaposi sarcoma herpesvirus (KSHV or HHV8) is the sole cause of Kaposi sarcoma, which primarily afflicts resource-poor and socially marginalized populations. This review summarizes a recent NIH-sponsored workshop's findings on the epidemiology and biology of KSHV as an overlooked but potentially vaccine-preventable infection. The unique epidemiology of this virus provides opportunities to prevent its cancers if an effective, inexpensive, and well-tolerated vaccine can be developed and delivered.

Cancer Incidence in Migrants in Australia: Patterns of Three Infection-Related Cancers

BACKGROUND

Australia provides an ideal population-base for cancer migration studies because of its multicultural society and high-quality cancer registrations. Among migrant groups there is considerable variability in the incidence of infection-related cancers; thus, the patterns of three such cancers were examined among migrant groups relative to Australian-born residents.

METHODS

Using national incidence data for cancers of the stomach, liver, and cervix diagnosed during 2005 to 2014, incidence rates were compared for selected migrant groups with the Australian-born population using incidence rate ratios (IRR), from a negative binomial regression model.

RESULTS

Wide variations in incidence between countries/regions of birth were observed for all three cancers (P < 0.0001). The patterns were similar for cancers of the stomach and liver, in that migrants from countries/regions with higher incidence rates maintained an increased risk in Australia, with the highest being among South American migrants (IRR = 2.35) for stomach cancer and among Vietnamese migrants (5.44) for liver cancer. In contrast, incidence rates of cervical cancer were lower for many migrant groups, with women from Southern Asia (0.39) and North Africa (0.42) having the lowest rates. The rate of cervical cancer was higher in migrants from New Zealand, Philippines, and Polynesia.

CONCLUSIONS

Several Australian migrant groups were found to experience a disproportionate burden of infection-related cancers; further studies of associated risk factors may inform the design of effective interventions to mediate these disparities.

IMPACT

By identifying these migrant groups, it is hoped that these results will motivate and inform prevention or early detection activities for these migrant groups. See related commentary Dee and Gomez, p. 1251.

Cancer types with high numbers of driver events are largely preventable

There is a long-standing debate on whether cancer is predominantly driven by extrinsic risk factors such as smoking, or by intrinsic processes such as errors in DNA replication. We have previously shown that the number of rate-limiting driver events per tumor can be estimated from the age distribution of cancer incidence using the gamma/Erlang probability distribution. Here, we show that this number strongly correlates with the proportion of cancer cases attributable to modifiable risk factors for all cancer types except the ones inducible by infection or ultraviolet radiation. The correlation was confirmed for three countries, three corresponding incidence databases and risk estimation studies, as well as for both sexes: USA, males (r = 0.80, P = 0.002), females (r = 0.81, P = 0.0003); England, males (r = 0.90, P < 0.0001), females (r = 0.67, P = 0.002); Australia, males (r = 0.90, P = 0.0004), females (r = 0.68, P = 0.01). Hence, this study suggests that the more driver events a cancer type requires, the more of its cases are due to preventable anthropogenic risk factors.

Establishment of Tree Shrew Animal Model for Kaposi's Sarcoma-Associated Herpesvirus (HHV-8) Infection

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the most common cause of Kaposi’s sarcoma (KS) and other malignant growths in humans. However, the lack of a KSHV-infected small animal model has hampered understanding of the mechanisms of KSHV infection, virus replication, pathogenesis, and persistence. This study was designed to explore the susceptibility of tree shrews as a possible KSHV-infected small animal model. A recombinant GFP (latent)/RFP (lytic)-positive rKSHV.219 strain was used to infect primary cells cultured from different tissues of tree shrews as an in vitro model and adult tree shrews as an in vivo model. KSHV latent nuclear antigen (LANA) and DNA were successfully detected in primary cells of tree shrews. Among them, tree shrew kidney epithelial cells (TSKEC) were the most susceptible cells to KSHV infection compared to other cells. KSHV genomic DNA, mRNA, and KSHV-specific proteins were readily detected in the TSKEC cultured up to 32 dpi. Moreover, KSHV DNA and mRNA transcription were also readily detected in the peripheral blood mononuclear cells (PBMCs) and various tissues of tree shrews infected with KSHV. Haematoxylin and eosin (HE) staining showed lymphocyte infiltration, lymphoid tissue focal aggregation, alveolar wall thickening, hepatocyte edema, hepatic necrosis in the spleen, lung, and liver of KSHV-infected animals. Additionally, immune-histochemical (IHC) staining showed that LANA or ORF62-positive cells were present in the spleen, lung, liver, and kidney of KSHV-infected tree shrews. Here, we have successfully established in vitro and in vivo KSHV latent infection in tree shrews. This small animal model is not only useful for studying the pathogenesis of KSHV in vivo but can also be a useful model to study transmission routes of viral infection and a useful platform to characterize the novel therapeutics against KSHV.

Projections of the future burden of cancer in Australia using Bayesian age-period-cohort models

BACKGROUND

Accurate forecasts of cancer incidence, with appropriate estimates of uncertainty, are crucial for planners and policy makers to ensure resource availability and prioritize interventions. We used Bayesian age-period-cohort (APC) models to project the future incidence of cancer in Australia.

METHODS

Bayesian APC models were fitted to counts of cancer diagnoses in Australia from 1982 to 2016 and projected to 2031 for seven key cancer types: breast, colorectal, liver, lung, non-Hodgkin lymphoma, melanoma and stomach. Aggregate cancer data from population-based cancer registries were sourced from the Australian Institute of Health and Welfare.

RESULTS

Over the projection period, total counts for these cancer types increased on average by 3 % annually to 100 385 diagnoses in 2031, which is a 50 % increase over 2016 numbers, although there is considerable uncertainty in this estimate. Counts for each cancer type and sex increased over the projection period, whereas decreases in the age-standardized incidence rates (ASRs) were projected for stomach, colorectal and male lung cancers. Large increases in ASRs were projected for liver and female lung cancer. Increases in the percentage of colorectal cancer diagnoses among younger age groups were projected. Retrospective one-step-ahead projections indicated both the incidence and its uncertainty were successfully forecast.

CONCLUSIONS

Increases in the projected incidence counts of key cancer types are in part attributable to the increasing and ageing population. The projected increases in ASRs for some cancer types should increase motivation to reduce sedentary behaviour, poor diet, overweight and undermanagement of infections. The Bayesian paradigm provides useful measures of the uncertainty associated with these projections.

Racial/Ethnic Differences in Cancers Attributable to Preventable Infectious Agents in Texas, 2015

OBJECTIVE

The International Agency for Research on Cancer has classified 13 infectious agents as carcinogenic or probably carcinogenic to humans. We aimed to estimate the percentage (ie, population-attributable fraction) and number of incident cancer cases in Texas in 2015 that were attributable to oncogenic infections, overall and by race/ethnicity.

METHODS

We calculated population-attributable fractions for cancers attributable to human papillomavirus (HPV), Helicobacter pylori, hepatitis C virus (HCV), hepatitis B virus (HBV), and human herpesvirus 8 (HHV-8) infections using prevalence estimates from National Health and Nutrition Examination Survey laboratory data and relative risks associated with infection from previous epidemiological studies. The Texas Cancer Registry provided cancer incidence data.

RESULTS

We estimated that 3603 excess cancer cases, or 3.5% of all cancers diagnosed in 2015, among adults aged ≥25 in Texas were attributable to oncogenic infections. Hispanic adults had the highest proportion of cancer cases attributable to infections (5.6%), followed by non-Hispanic Black (5.4%) and non-Hispanic White (2.3%) adults. HPV infection caused the highest proportion of all cancer cases (1.8%) compared with other oncogenic infections (HCV, 0.8%; H pylori, 0.5%; HBV, 0.3%; HHV-8, 0.1%). Hispanic adults had the highest proportions of all cancers caused by HPV infection (2.6%) and H pylori (1.1%), and non-Hispanic Black adults had the highest proportions of all cancers caused by HCV infection (1.7%), HBV infection (0.7%), and HHV-8 (0.3%).

CONCLUSION

Preventable oncogenic infections contribute to cancer incidence in Texas and may affect racial/ethnic minority groups disproportionately. Infection control and prevention should be stressed as an important component of cancer prevention.

Co-presence of human papillomaviruses and Epstein-Barr virus is linked with advanced tumor stage: a tissue microarray study in head and neck cancer patients

Background

Human papillomaviruses (HPVs) and Epstein–Barr virus (EBV), known oncoviruses, can be co-present and cooperate in the initiation and/or progression of human carcinomas, including head and neck. Based on this fact, we recently reported the prevalence of both HPVs and EBV in cervical and breast cancers.

Methods

We herein explore for the first time the co-prevalence of high-risk HPVs and EBV in 98 head and neck (HN) squamous cell carcinoma (SCC) tissues from Bosnian patients using polymerase chain reaction (PCR) and immunohistochemistry (IHC) analysis, as well as tissue microarray methodology.

Results

The majority of these cancer tissue cases were from the oral cavity (68%). We found that high-risk HPVs and EBV are co-present in 34.7% of the SCC samples; with a significant correlation between the various HPV types and EBV co-incidence (p = 0.03). Our data showed that 30.8% of oral SCCs are positive for E6 oncoprotein of high-risk HPVs and 44.6% are positive for LMP1 of EBV. The most commonly expressed HPVs in our HNSCC samples include HPV types 16, 18, 45 and 58. Additionally, 37.5% of oral SCCs are positive for both HPVs and EBV, with statistically significant association between high-risk HPV types and EBV (p < 0.05). More importantly, our data revealed that the co-presence of HPV and EBV is strongly correlated with advanced tumor stage (p = 0.035).

Conclusion

In this study we show that HPV and EBV oncoviruses are co-present in HNSCC, particularly in oral cancer, where they can cooperate in the initiation and/or progression of this cancer. Thus, further studies are necessary to elucidate the mechanism of this cooperation.

Emerging Evidence for Infectious Causes of Cancer in the United States

Worldwide, infectious agents currently contribute to an estimated 15% of new cancer cases. Most of these (92%, or 2 million new cancer cases) are attributable to 4 infectious agents: Helicobacter pylori, human papillomavirus, and hepatitis B and C viruses. A better understanding of how infectious agents relate to the US cancer burden may assist new diagnostic and treatment efforts. We review US-specific crude mortality rates from infection-associated cancers and describe temporal and spatial trends since 1999. We review the US-specific evidence for infection-cancer associations by reporting available estimates for attributable fractions for the infection-cancer associations. Death due to cancers with established infectious associations varies geographically, but estimates for the US attributable fraction are limited to a few observational studies. To describe the burden of infection-associated cancer in the United States, additional observational studies are necessary to estimate the prevalence of infection nationally and within subpopulations. As infectious associations emerge to explain cancer etiologies, new opportunities and challenges to reducing the burden arise. Improved estimates for the United States would help target interventions to higher-risk subpopulations.

Scientific evidence supporting recommendations on the use of the 9-valent HPV vaccine in a 2-dose vaccine schedule in Australia

The Australian Technical Advisory Group on Immunisation (ATAGI) updated recommendations on the use of human papillomavirus (HPV) vaccines in the Australian Immunisation Handbook in 2018, regarding the use of the recently available 9-valent (9vHPV) vaccine, Gardasil 9, and a 2-dose schedule for young adolescents for HPV vaccines. This report provides an overview of the relevant scientific evidence that underpinned these updated recommendations. The 9vHPV vaccine includes 5 HPV types (HPV 31, 33, 45, 52 and 58) additional to the 4 that are also covered by the 4vHPV (Gardasil) vaccine (HPV 6,11,16,18). Accordingly, the 9vHPV vaccine is expected to prevent an additional 15% of cervical cancers and up to 20% of other HPV-related cancers. Non-inferior antibody responses after two 9vHPV vaccine doses given 6-12 months apart in girls and boys aged 9-14 years compared to women aged 16-26 years after three doses support the 2-dose schedule for adolescents of this age group. In clinical trials 9vHPV vaccine was well-tolerated with a similar safety profile to 4vHPV vaccine. The switch to 9vHPV vaccine and a 2-dose schedule is anticipated to improve public acceptability of the program and reduce HPV-related disease in the long-term.

Co-prevalence of human Papillomaviruses (HPV) and Epstein-Barr virus (EBV) in healthy blood donors from diverse nationalities in Qatar

BACKGROUND

Infections by both human oncoviruses, human Papillomaviruses (HPV) and Epstein-Barr virus (EBV) are very common in the adult human population and are associated with various malignancies. While HPV is generally transmitted sexually or via skin-to-skin contact, EBV is frequently transmitted by oral secretions, blood transfusions and organ transplants. This study aims to determine the prevalence and circulating genotypes of HPV and EBV in healthy blood donors in Qatar.

METHODS

We explored the co-prevalence of high-risk HPVs and EBV in 378 males and only 7 females blood donors of different nationalities (mainly from Qatar, Egypt, Syria, Jordan, Pakistan, and India) residing in Qatar, using polymerase chain reaction (PCR). DNA was extracted from the buffy coat and genotyping was performed using PCR and nested-PCR targeting E6 and E7 as well as LMP-1 of HPV and EBV, respectively.

RESULTS

We found that from the total number of 385 cases of healthy blood donors studied, 54.8% and 61% of the samples are HPVs and EBV positive, respectively. Additionally, our data revealed that the co-presence of both high-risk HPVs and EBV is 40.4% of the total samples. More significantly, this study pointed out for the first time that the most frequent high-risk HPV types in Qatar are 59 (54.8%), 31 (53.7%), 52 (49.1%), 51 (48.6%), 58 (47%) and 35 (45.5%), while the most commonly expressed low-risk HPV types are 53 (50.6%), 11 (45.5), 73 (41.7%) and 6 (41.3%), with all the cases showing multiple HPVs infection.

CONCLUSION

In this study, we demonstrated for the first time that HPV and EBV are commonly co-present in healthy blood donors in Qatar. On the other hand, it is important to highlight that these oncoviruses can also be co-present in several types of human cancers where they can cooperate in the initiation and/or progression of these cancers. Therefore, more studies regarding the co-presence of these oncoviruses and their interaction are necessary to understand their cooperative role in human diseases.

Estimates of the incidence of infection-related cancers in Italy and Italian regions in 2018

Introduction

Chronic infections and infestations represent one of the leading causes of cancer. Eleven agents have been categorized by the International Agency for Research on Cancer (IARC) in Group 1, 3 in Group 2A and 4 in Group 2B. We previously estimated that the incidence of cancers associated with infectious agents accounted for the 8.5% of new cancer cases diagnosed in Italy in 2014.

Methods

In the present study we evaluated the incidence of cancer in Italy and in the 20 Italian regions in 2018, based on the data of Cancer Registries, and calculated the fraction attributable to infectious agents.

Results

Cancers of infectious origin contributed to the overall burden of cancer in Italy with more than 27,000 yearly cases, the 92% of which was attributable to Helicobacter pylori, human papillomaviruses, and hepatitis B and C viruses. With the exception of papillomavirus-related cancers, the incidence of cancers of infectious origin was higher in males (16,000 cases) than in females (11,000 cases). There were regional and geographical variations of cancers depending on the type of cancer and on the gender. Nevertheless, the overall figures were rather similar, the infection-related cancers accounting for the 7.2, 7.6, and 7.1% of all cancers in Northern, Central, and Southern Italy, respectively.

Conclusions

The estimate of the incidence of cancers attributable to infectious agents in Italy in 2018 (7.3% of all cancer cases) is approximately half of the worldwide burden, which has been estimated by IARC to be the 15.4% of all cancer cases in 2012.

The impact of 10 years of human papillomavirus (HPV) vaccination in Australia: what additional disease burden will a nonavalent vaccine prevent?

Background: A National human papilloma virus (HPV) Vaccination Programme for the prevention of HPV infection and associated disease using the quadrivalent HPV vaccine (4vHPV) has been funded and implemented in Australia since 2007, initially for girls only and extended to boys in 2013, with uptake rates among the highest observed worldwide. Aim: We report on the impact of this national programme on HPV prevalence and associated disease burden and estimate the potential impact of adopting a nonavalent HPV (9vHPV) vaccine. Methods: We performed a non-systematic literature review of studies measuring the burden of HPV-associated disease and infection in Australia before and after introduction of HPV vaccination. We also included key national reports with estimates of HPV-related disease burden. Results: Substantial declines in high-grade cervical disease and genital warts among vaccine-eligible women have been observed. Reductions in genital warts incidence and HPV prevalence among heterosexual men of similar age were observed before introduction of the male vaccination programme, indicating a substantial herd effect. 9vHPV vaccine is expected to prevent up to 90% of cervical and 96% of anal cancers. Of an estimated 1,544 HPV-associated cancers in 2012, 1,242 would have been preventable by the 4vHPV vaccine and an additional 187 anogenital cancers by the 9vHPV vaccine. Conclusions: Vaccination using 4vHPV vaccine has had a large demonstrable impact on HPV-related disease in Australia. A switch to 9vHPV could further reduce the HPV-associated cancer burden. With continued high coverage among both males and females, elimination of vaccine-type HPV disease seems achievable in Australia.

Cancers attributable to infections in Canada

Infections are estimated to cause approximately 15% of the world's cancers with large geographic variations. Yet, Canadian estimates for specific cancer-causing infections are not available. To estimate the number of infection-associated cancers diagnosed among Canadian adults in 2015, we calculated population attributable risks (PARs) and the number of attributable cases for seven carcinogenic infections and their 20 associated cancers. A systematic literature search was performed for each infection to obtain data on infection prevalence in the population and the relative risk or odds ratio associated with the cancer it causes. When mechanistic evidence suggested that detection of a given infection within cancer tissue was sufficient to attribute the cancer to the infection, prevalence among cancer cases was used to approximate the PAR. Data from 61 studies formed the basis of our analyses. The estimated number of infection-attributable cancer cases for 2015 was: 3828 for human papillomavirus (HPV), 2052 for Helicobacter pylori, 578 for Epstein-Barr virus, 509 for hepatitis B and C viruses (HBV, HCV), 100 for human herpesvirus type 8, and 30 cases for human T-cell lymphotropic virus type 1. These seven infections were responsible for 3.7% of cancers diagnosed among Canadian adults in 2015; 3.5% among men and 4.0% among women. The infections with the highest number of attributable cases are largely preventable or treatable through vaccination (HBV and HPV), antibiotic therapy (H. pylori), or a combination of interventions (HCV), thereby representing an important target for reducing the infection-caused cancer burden among Canadians.

Management of ASC-US/HPV positive post-menopausal woman

BACKGROUND

The aim of our study was to determine which diagnostic course is best to identify women at risk of CIN2+ among post-menopausal women with cytological diagnosis of ASCUS METHODS: We selected women who had been post-menopausal for at least one year , and who had completed the entire diagnostic-therapeutic course that they had undertaken. The sample was divided into two arms: in the first arm, we considered 146 ASCUS positive women who had undergone the HPV test, colposcopy and then underwent more detailed diagnostics by means of LEEP or a scraping of the cervical canal. The second arm was made up of 124 ASCUS positive women who had undergone a vaginal administration of estriolo, the HPV test and colposcopy. Estriol was administered for 5 weeks: the first week one vaginal suppository every evening, the other four weeks the administration was twice a week. Then, the patients underwent colposcopy. In cases of positivity a biopsy was carried out, the patients positive for CIN2+ at the biopsy underwent excisional therapy using LEEP and were followed up. The patients, who were negative at colposcopy or with histological diagnosis of CIN1, were examined again at 1 year.

RESULTS

In the first arm the HPV test had an SE of 94%, an SP of 68%, NPV of 99%, and PPV of 28%. The PPV is very low because of the elevated percentage of false positives that the HPV test gave (71%). In the second arm the HPV test maintained its high SE (100%), an SP of 74%, a NPV of 100%, and a PPV of 43%. The use of estrogen increased the specificity of the test.

CONCLUSION

It is important to say that the second arm indicates the use of local estrogen therapy only for ASCUS/HPV positive postmenopausal women. Therefore, the HPV test should be used as the first diagnostic possibility in cases of ASCUS in post-menopausal women, associating local estrogen therapy only with HPV positive women.

Fraction and incidence of liver cancer attributable to hepatitis B and C viruses worldwide

High-quality data on liver cancers by probable cause are scarce in many regions of the world. The United Nations recently set a goal of eliminating viral hepatitis as a major public health threat by 2030. We aimed to estimate the number of new cases of cancers attributable to hepatitis B virus (HBV) and hepatitis C virus (HCV) at a global, regional and country level, and by development status. We used data on the prevalence of HBV and HCV in hepatocellular carcinoma from a systematic review including 119,000 cases in 260 studies covering 50 countries. A statistical model was constructed to extrapolate empirical data to countries without prevalence data. Country-specific numbers of liver cancer cases attributable to HBV and HCV were calculated using data from GLOBOCAN 2012. Globally, 770,000 cases of liver cancer occurred worldwide in 2012, of which 56% (95% CI: 52-60) were attributable to HBV and 20% (95% CI: 18-22) to HCV. Currently, HBV causes approximately two out of three cases of liver cancer in less developed countries but one in four cases in more developed countries and shows a much higher degree of geographical aggregation in Eastern Asia and sub-Saharan Africa than HCV. These estimates help set priorities for liver cancer prevention. High-coverage HBV vaccination will be transformational in HBV-endemic countries but the prevention of HCV transmission and the treatment of chronic carriers of both viruses requires new scalable solutions.

Repetibilidade e reprodutibilidade de um manual de exercícios físicos domiciliares

RESUMO Verificou-se a reprodutibilidade e repetibilidade de um manual de exercícios físicos domiciliares em diferentes níveis de escolaridade em idosas com câncer de mama. Estudo seccional realizado entre agosto e novembro de 2016 no Instituto de Medicina Integral Professor Fernando Figueira (Imip), região metropolitana de Recife, Pernambuco. Vinte e duas idosas (idade 66.2±3.5 anos) diagnosticadas com câncer de mama em uso de hormonioterapia receberam um manual instrucional composto por 12 exercícios, a serem realizados de forma autônoma e independente em domicílio para melhoria das aptidões físicas. O manual foi entregue na primeira consulta e após seis semanas verificou-se sua reprodutibilidade por meio da avaliação de concordância em “certo” ou “errado” dos movimentos por um profissional de educação física e um fisioterapeuta. Os resultados foram analisados pelo coeficiente kappa de Cohen (k). Verificou-se uma relação interavaliadores de concordância “quase perfeita” (superior a 0,88) entre todos os 12 exercícios. Considerando a execução “certa” dos movimentos, verificou-se que seis exercícios apresentaram concordância interavaliadores com variação entre 68,2% e 90,9%; por outro lado, quando considerada a execução “errada”, observou-se variação entre 54,4% e 68,2%. Além disso, dois exercícios resultaram em 50% para “certo” e “errado”. Quanto ao nível de escolaridade, apenas o exercício 6 apresentou significância estatística (p-valor=0,03). O manual de exercícios físicos domiciliares parece ser reprodutível em idosas com câncer de mama em todos os níveis de escolaridade, para melhorar a aptidão física e promover o autocuidado funcional.

The Role of Epstein-Barr Virus in Cervical Cancer: A Brief Update

Epstein–Barr virus (EBV) belongs to the group of gamma-herpes viruses and was the first recognized human oncovirus. EBV is responsible for infectious mononucleosis and multiple lymphoid and epithelial malignancies including B-cell lymphomas (Burkitt lymphoma, Hodgkin lymphoma, and post-transplant lymphoproliferative disorder), various T-cell/NK lymphoproliferative disorders, nasopharyngeal carcinoma, and gastric carcinoma, respectively. In addition, the presence of EBV has been documented in other cancers including breast, prostate, oral, and salivary gland carcinomas. The presence and role of EBV in cervical cancer and its precursor lesions (CIN) have also been described, but the results from the literature are inconsistent, and the causal role of EBV in cervical cancer pathogenesis has not been established yet. In the present review, we briefly surveyed and critically appraised the current literature on EBV in cervical cancer and its variants (lymphoepithelioma-like carcinoma) as well as its precursor lesions (CIN). In addition, we discussed the possible interactions between EBV and human papilloma virus as well as between EBV and immune checkpoint regulators (PD-L1). Though further studies are needed, the available data suggest a possible causal relationship between EBV and cervical cancer pathogenesis.

New cancer cases in France in 2015 attributable to infectious agents: a systematic review and meta-analysis

To provide an assessment of the burden of cancer in France in 2015 attributable to infectious agents. A systematic literature review in French representative cancer cases series was undertaken of the prevalence of infectious agents with the major associated cancer types. PubMed was searched for original studies published up to September 2016; random-effects meta-analyses were performed. Cancer incidence data were obtained from the French Cancer Registries Network, thereby allowing the calculation of national incidence estimates. The number of new cancer cases attributable to infectious agents was calculated using population-attributable fractions according to published methods. Of the 352,000 new cancer cases in France in 2015, 14,336 (4.1% of all new cancer cases) were attributable to infectious agents. The largest contributors were human papillomavirus (HPV) and Helicobacter pylori, responsible for 6333 and 4406 new cancer cases (1.8 and 1.3% of all new cancer cases) respectively. Infectious agents caused a non-negligible number of new cancer cases in France in 2015. Most of these cancers were preventable. The expansion of vaccination (i.e., for hepatitis B virus and HPV) and screen-and-treat programs (for HPV and hepatitis C virus, and possibly for H. pylori) could greatly reduce this cancer burden.

Cancer incidence in Germany attributable to human papillomavirus in 2013

BACKGROUND

It is estimated that a total of 120,000 new cancer cases in men and in women in more developed countries could be avoided if exposure to HPV was prevented. We used the nationwide pool of German population-based cancer registry data to estimate the burden of HPV-attributable cancer in this population for the year 2013.

METHODS

Incident cases of cervical cancer, squamous cell carcinoma of the anus, oropharynx (OP), as well as of the vulva, vagina and penis were classified as potentially HPV-associated and identified from the nationwide cancer registry data-pool. We calculated the incidence and proportions of cancer with potentially HPV-associated morphologies. Estimation of the HPV-attributable incidence was based on prevalence-estimates of viral DNA in tumor cells in the respective sites, as provided from the international literature.

RESULTS

From the overall 15,936 incident cases of anogenital and OP cancers in 2013, 6239 female and 1358 male cancer cases were estimated to be attributable to HPV. The majority of HPV-attributable cases were contributed by cervical cancer (70.9% of female cancers) and oropharyngeal cancer (46.9% of male cancers).

CONCLUSIONS

Even if most HPV-attributable cases were contributed by cervical cancer, anogenital cancer at sites other than the cervix, and oropharyngeal cancer substantially contribute to the burden of HPV-associated cancer. Our nationwide cancer registry data-analyses provide the baseline for long-term population-based monitoring of vaccination-effects on cancer incidence in Germany.

Eradicating hepatitis C: The need for a public health response

Hepatitis C is a global public health issue affecting 150-170 million people worldwide, and over 227,000 Australians with an increasing morbidity resulting from the infection. The Australian Government funded access through the national health scheme to Direct Acting Antiviral (DAA) medication for all people with hepatitis C, regardless of disease staging or mode of transmission to eradicate hepatitis C in Australia. The availability of these drugs not only alters the end result of hepatitis C treatment from that of sustained viral response to cure, but necessitates a refocusing of the public health response to hepatitis C. This project, conducted prior to this funding announcement, interviewed key stakeholders in Australia to investigate the potential impact of DAAs on individuals with hepatitis C and their public health implications. The findings include that while DAAs are revolutionary, there remains essential barriers to their uptake including stigma and discrimination, and a lack of attention to the systematic implementation of the cure.

Cancers in Australia in 2010 attributable to modifiable factors: introduction and overview

OBJECTIVE

To describe the approach underpinning a national project to estimate the numbers and proportions of cancers occurring in Australia in 2010 that are attributable to modifiable causal factors.

METHODS

We estimated the population attributable fraction (PAF) (or prevented fraction) of cancers associated with exposure to causal (or preventive) factors using standard formulae. Where possible, we also estimated the potential impact on cancer incidence resulting from changes in prevalence of exposure. Analyses were restricted to factors declared causal by international agencies: tobacco smoke; alcohol; solar radiation; infectious agents; obesity; insufficient physical activity; insufficient intakes of fruits, vegetables and fibre; red and processed meat; menopausal hormone therapy (MHT); oral contraceptive pill (OCP); and insufficient breast feeding. Separately, we estimated numbers of cancers prevented by: aspirin; sunscreen; MHT; and OCP use. We discuss assumptions pertaining to latent periods between exposure and cancer onset, choices of prevalence data and risk estimates, and approaches to sensitivity analyses.

RESULTS

Numbers and population attributable fractions of cancer are presented in accompanying papers.

CONCLUSIONS

This is the first systematic assessment of population attributable fractions of cancer in Australia.

Cancers in Australia in 2010 attributable to modifiable factors: summary and conclusions

OBJECTIVE

To estimate the numbers and proportions of cancers occurring in Australia in 2010 attributable to modifiable causal factors.

METHODS

We estimated the population attributable fraction (PAF) of cancers associated with exposure to 13 causal factors using standard formulae incorporating exposure prevalence and relative risk data. We also calculated the potential impact of changing exposure to some factors.

RESULTS

A total of 32% of all cancers diagnosed in Australia in 2010 (excluding keratinocyte cancers) were attributable to the 13 factors assessed (men 33%; women 31%). Leading factors were tobacco smoke (PAF all cancers: 13.4%), solar radiation (6.2%), inadequate diet (6.1%) and overweight/obesity (3.4%). Factors conferring highest PAFs differed by sex: highest PAFs for men were tobacco smoke (15.8%), solar radiation (7.1%) and alcohol (3.0%); while highest PAFs for women were tobacco smoke (10.1%), solar radiation (5.0%) and overweight/obesity (4.5%). Sites with the highest counts of potentially preventable cancers were lung (8,569), colorectal (7,404), melanoma of the skin (7,220) and breast (3,233).

CONCLUSIONS

At least one in three cancers in Australia is attributable to exposure to known modifiable factors.

IMPLICATIONS

Up to 37,000 cancers could be prevented in Australia each year if the population avoided exposure to 13 common factors known or strongly suspected to cause cancer.