Efficacy of a bivalent HPV 16/18 vaccine against anal HPV 16/18 infection among young women: a nested analysis within the Costa Rica Vaccine Trial

Prospects for prevention of HPV-driven oropharynx cancer

Prevention of HPV-associated cancers can take two forms-one through prevention of infection via prophylactic HPV vaccination, and one through interruption of disease progression through early identification (i.e.: screening) and treatment. Primary prevention via vaccination seems promising, as a proof-of-principal study demonstrated high vaccine efficacy against one-time detection of oral HPV16/18 infection. In addition to the direct benefit of vaccination, indirect protection from reduced genital HPV infection should also reduce oral HPV exposure at the individual level. Yet, for the current unvaccinated cohorts who will bear the burden of non-cervical HPV-associated cancers for the foreseeable future, no secondary prevention opportunities exist, as the field has not yet validated any screening methods for non-cervical HPV associated cancers. Serum HPV16 E6 antibody data suggest that this test might one day be able to detect many of the at-risk patients prior to tumor development. For any biomarker that proves valid and reliable, transitioning into clinical practice will require additional research focused on (1) diagnostics, (2) effective intervention, and (3) observed reductions in cancer mortality.

Reduced prevalence of oral human papillomavirus (HPV) 4 years after bivalent HPV vaccination in a randomized clinical trial in Costa Rica

Background

Human papillomavirus (HPV) infection, particularly with type 16, causes a growing fraction of oropharyngeal cancers, whose incidence is increasing, mainly in developed countries. In a double-blind controlled trial conducted to investigate vaccine efficacy (VE) of the bivalent HPV 16/18 vaccine against cervical infections and lesions, we estimated VE against prevalent oral HPV infections 4 years after vaccination.

Methods and Findings

A total of 7,466 women 18–25 years old were randomized (1∶1) to receive the HPV16/18 vaccine or hepatitis A vaccine as control. At the final blinded 4-year study visit, 5,840 participants provided oral specimens (91·9% of eligible women) to evaluate VE against oral infections. Our primary analysis evaluated prevalent oral HPV infection among all vaccinated women with oral and cervical HPV results. Corresponding VE against prevalent cervical HPV16/18 infection was calculated for comparison. Oral prevalence of identifiable mucosal HPV was relatively low (1·7%). Approximately four years after vaccination, there were 15 prevalent HPV16/18 infections in the control group and one in the vaccine group, for an estimated VE of 93·3% (95% CI = 63% to 100%). Corresponding efficacy against prevalent cervical HPV16/18 infection for the same cohort at the same visit was 72·0% (95% CI = 63% to 79%) (p versus oral VE = 0·04). There was no statistically significant protection against other oral HPV infections, though power was limited for these analyses.

Conclusions

HPV prevalence four years after vaccination with the ASO4-adjuvanted HPV16/18 vaccine was much lower among women in the vaccine arm compared to the control arm, suggesting that the vaccine affords strong protection against oral HPV16/18 infection, with potentially important implications for prevention of increasingly common HPV-associated oropharyngeal cancer.

ClinicalTrials.gov, Registry number NCT00128661

Risk of human papillomavirus-related cancers among kidney transplant recipients and patients receiving chronic dialysis--an observational cohort study

Background

Individuals with end-stage renal disease (ESRD) have excess risk of various cancer types. However, the total burden of human papillomavirus-related cancers remains unknown.

Methods

We performed a nationwide observational cohort study during 1994–2010.

For each person with ESRD, we sampled 19 population controls (without ESRD) matched on age, gender and municipality. Participants were followed until first diagnosis of human papillomavirus-related cancer, death, emigration, or 31 December 2010, whichever came first.

Human papillomavirus-related cancers were extracted from Danish medical administrative databases. We considered cancers of the cervix, vulva, vagina, penis, anus, and subsets of head and neck cancers as human papillomavirus-related. We calculated incidence rates of human papillomavirus-related cancer and used Poisson regression to identify risk factors for human papillomavirus-related cancer.

Results

Among 12,293 persons with ESRD and 229,524 population controls we identified 62 and 798 human papillomavirus-related cancers, respectively. Incidence rates of human papillomavirus-related- cancer were 102 per 100,000 person-years (95% confidence interval [CI]; 79.5-131) among persons with ESRD and 40.8 per 100,000 person-years (95% CI; 38.1-43.7) among population controls. ESRD patients had 4.54 (95% CI, 2.48-8.31) fold increased risk of anal cancer and 5.81 fold (95% CI; 3.36-10.1) increased risk of vulvovaginal cancer. Adjusted for age, comorbidity, and sex, ESRD patients had 2.41 (95% CI; 1.83-3.16) fold increased risk of any human papillomavirus-related cancer compared with population controls. Compared with dialysis patients renal transplant recipients had an age-adjusted non-significant 1.53 (95% CI, 0.91-2.58) fold higher risk of human papillomavirus-related cancer.

Conclusions

Persons with ESRD have excess risk of potentially vaccine-preventable human papillomavirus-related cancers.

Clinical trials of human papillomavirus vaccines and beyond

Human papillomavirus (HPV) is the most common sexually transmitted infectious agent; its 14 oncogenic types are causally associated with 5-10% of all cancers. The major structural HPV protein self-assembles into immunogenic virus-like particles. Two licensed HPV vaccines--the bivalent vaccine comprising HPV types 16 and 18, and the quadrivalent vaccine comprising HPV types 6, 11, 16 and 18--have proven to be safe and efficacious against 6-month-persistent cervical infections of HPV16 and HPV18 and associated precancerous lesions, and both have efficacies of 90-100%. Among baseline HPV-negative adolescent females, vaccine efficacies against the immediate precursor of cervical cancer (intraepithelial neoplasia grade 3) irrespective of HPV type are 93.2% and 43.0% for the bivalent and quadrivalent vaccines, respectively. The quadrivalent vaccine is efficacious (>75% vaccine efficacy) against any of the more-severe precursors of vulval, vaginal and anal cancers. A strong increase in vaccine efficacy with increasing severity of the precancerous lesion is explained by accumulation of the most-oncogenic HPV types 16 and 18 in these lesions. Therefore, prophylactic HPV vaccination will exceed the best results from screening for cancer. With the extremely efficacious prophylactic HPV vaccines, the focus of organized intervention (vaccination and screening) programmes should, however, shift from reducing the HPV disease burden to controlling the prevalence of oncogenic HPV (and nononcogenic HPV) types. Eradication of the major oncogenic HPV types should be pursued.

Human papillomavirus vaccination: current indications and future directions

Human papillomavirus (HPV) is one of the most common sexually transmitted infections affecting both men and women worldwide. The development of the prophylactic HPV vaccines is a significant pharmaceutical innovation with potential to reduce HPV-related morbidity. However, barriers to the universal use and acceptability of the HPV vaccines continue to exist in both economically privileged and disadvantaged countries. It may be decades before the impact of preventive vaccines on HPV-related diseases caused by the considerable burden of HPV infections will be seen. Collaborative efforts must continue to promote vaccine implementation.

HPV vaccination and cervical cancer

Cervical cancer is the third most common cancer in women worldwide and often affects women under 40 years with young families. Vaccination against the human papillomavirus (HPV) is a major advance, since it offers primary prevention against the infectious agent that is the main cause of the disease. Two prophylactic vaccines have shown great promise in clinical trials. One of these (Gardasil(®)) contains all four HPV types, offering protection against genital warts (types 6 and 11) as well as cervical cancer (types 16 and 18). The other (Cervarix(®)) contains types 16 and 18, targeting cervical cancer alone, but also has a degree of cross-protection against types 31 and 45, which could significantly increase the level of protection. Adolescent girls remain the primary target of vaccination programmes, but the issues of vaccinating boys and older women are increasingly debated.

[The first vaccine against cancer: the human papillomavirus vaccine]

The last 20 years is one of the most remarkable periods in the fight against cancer, with the realization that some human papillomaviruses are causally related to cancer and with the development of the vaccine against human papillomavirus infections. This is a historical event in medicine and the prophylactic human papillomavirus vaccines have provided powerful tools for primary prevention of cervical cancer and other human papillomavirus-associated diseases. This is very important as human papillomavirus infection is probably the most common sexually transmitted infection worldwide, and over one million women develop associated cancer yearly, which is about 5% of all female cancers, and half of them die of their disease. Cancers associated with oncogenic human papillomaviruses, mostly HPV16 and 18, include cervical cancer (100%), anal cancer (95%), vulvar cancer (40%), vaginal cancer (60%), penile cancer (40%), and oro-pharingeal cancers (65%). In addition, pre-cancers such as genital warts and the rare recurrent respiratory papillomatosis are also preventable by vaccination. Currently, the human papillomavirus vaccines have the potential to significantly reduce the burden of human papillomavirus associated conditions, including prevention of up to 70% of cervical cancers. Two prophylactic human papillomavirus vaccines are currently available worldwide: a bivalent vaccine (types 16 and 18), and a quadrivalent vaccine (types 6, 11, 16, and 18). Randomized controlled trials conducted on several continents during the last 10 years have demonstrated that these vaccines are safe without serious side effects; they are highly immunogenic and efficacious in preventing incident and persistent vaccine-type human papillomavirus infections, high grade cervical, vulvar and vaginal intraepithelial neoplasia and so on. In addition, the quadrivalent vaccine has been shown to prevent genital warts in women and men. The vaccine is most effective when given to human papillomavirus naive girls. The human papillomavirus vaccines have been incorporated into national immunization programs in 22 European countries. Routine vaccination is recommended for girls aged between 9 and 13 years and catch-up vaccination for females between 13 and 25 years of age. There is no excuse not to incorporate the vaccines into the Hungarian national immunization program. Albeit vaccination is expensive, it is cost-effective in the long run definitely. Anyway, vaccination is a matter of the specialty and the national health program, but not of business. We all are obliged to prevent human suffering.

L2, the minor capsid protein of papillomavirus

The capsid protein L2 plays major roles in both papillomavirus assembly and the infectious process. While L1 forms the majority of the capsid and can self-assemble into empty virus-like particles (VLPs), L2 is a minor capsid component and lacks the capacity to form VLPs. However, L2 co-assembles with L1 into VLPs, enhancing their assembly. L2 also facilitates encapsidation of the ∼8 kbp circular and nucleosome-bound viral genome during assembly of the non-enveloped T=7d virions in the nucleus of terminally differentiated epithelial cells, although, like L1, L2 is not detectably expressed in infected basal cells. With respect to infection, L2 is not required for particles to bind to and enter cells. However L2 must be cleaved by furin for endosome escape. L2 then travels with the viral genome to the nucleus, wherein it accumulates at ND-10 domains. Here, we provide an overview of the biology of L2.

Incidence of potentially human papillomavirus-related neoplasms in the United States, 1978 to 2007

BACKGROUND

Population-based studies comprehensively describing incidence patterns of human papillomavirus (HPV)-related preinvasive and invasive neoplasms prior to widespread HPV vaccination are sparse.

METHODS

Age-adjusted incidence rates (IRs), IR ratios (IRRs), and annual percent changes (APCs) in IRs were calculated for potentially HPV-related tumors diagnosed in the Surveillance, Epidemiology and End Results (SEER) Program during 1978 through 2007.

RESULTS

Overall IRs for preinvasive tumors were significantly higher than for invasive squamous cell tumors of cervix (IRR = 3.42), vulva (IRR = 1.87), and vagina (IRR = 1.19) and significantly lower for adenomatous cervical tumors (IRR = 0.43), and squamous cell tumors of penis (IRR = 0.64), anus (males, IRR = 0.53; females, IRR = 0.14), and head and neck (H&N) (males, IRR = 0.01; females, IRR = 0.02). Incidence of preinvasive squamous tumors of cervix, vagina, and penis rose rapidly over time and decreased for invasive neoplasms. The most rapid increases occurred for preinvasive (males, APC = 16.0; females, APC = 7.3) and invasive anal tumors (males, APC = 3.6; females, APC = 2.3). IR patterns were generally similar among evaluable racial/ethnic groups, with the exception of H&N invasive tumor IRs which increased exclusively among white males.

CONCLUSIONS

Contrary to the opposing trends of preinvasive and invasive squamous tumors of cervix, vagina, and penis, preinvasive and invasive anal tumor IRs increased significantly over time by sex, age, and racial/ethnic groups. Successful HPV vaccination programs are needed to measurably reduce incidence of HPV-related neoplasms in the future, particularly for cancer sites with rising incidence rates for which effective screening modalities are limited. Cancer 2013;119:2291-2299. © 2013 American Cancer Society.

Clinical update: colon, rectal, and anal cancers

OBJECTIVES

To present an updated review of the incidence, risk factors, staging, diagnosis, and treatment of colon, rectal, and anal cancers, as well as nursing care associated with managing patients diagnosed with these malignancies.

DATA SOURCES

Published research reports, epidemiologic data, published patient management guidelines, and institution-based clinical tools.

CONCLUSION

While significant advances in the management of colon, rectal, and anal cancers in the past decade have extended patient survival, there remain some unanswered questions. Further clinical and molecular research will help individualize patient care, refining current therapeutic strategies and treatment decision-making aids while minimizing symptoms of disease and treatment.

IMPLICATIONS FOR NURSING PRACTICE

Nurses need to be familiar with risk factors, disease course, and current and emerging therapies to assist patients with treatment decision-making, and to anticipate and intervene in managing disease and treatment-induced problems. Early identification and management of distressing symptoms can help to avoid life-threatening effects and promote patient adherence to prescribed therapies; timely patient/family education may minimize anxiety and promote self-management.

A comparative analysis of the epidemiological impact and disease cost-savings of HPV vaccines in France

The aim was to compare the epidemiological and economic impact of 16/18 bivalent and 6/11/16/18 quadrivalent HPV vaccination in France, considering differences in licensed outcomes, protection against non-vaccine HPV types and prevention of HPV-6/11-related diseases.

The differential impact of the two vaccines was evaluated using a published model adapted to the French setting. The target population was females aged 14–23 y and the time horizon was 100 y. A total of eight different scenarios compared vaccination impact in terms of reduction in HPV-16/18-associated carcinomas (cervical, vulvar, vaginal, anal, penile and head and neck), HPV-6/11-related genital warts and recurrent respiratory papillomatosis, and incremental reduction in cervical cancer due to potential cross-protection.

Quadrivalent vaccine was associated with total discounted cost savings ranging from EUR 544–1,020 million vs. EUR 177–538 million with the bivalent vaccination (100-y time horizon). Genital wart prevention thanks to quadrivalent HPV vaccination accounted for EUR 306–380 million savings (37–56% of costs saved). In contrast, the maximal assumed cross-protection against cervical cancer resulted in EUR 13–33 million savings (4%). Prevention of vulvar, vaginal and anal cancers accounted for additional EUR 71–89 million savings (13%).

In France, the quadrivalent HPV vaccination would result in significant incremental epidemiological and economic benefits vs. the bivalent vaccination, driven primarily by prevention of genital. The present analysis is the first in the French setting to consider the impact of HPV vaccination on all HPV diseases and non-vaccine types.

Laboratory management of cervical intraepithelial neoplasia: proposing a new paradigm

Since the discovery of human papillomavirus (HPV) type 16 in early 80s, the link between HPV and cervical cancer has been established with certainty, a function of the discovery and cloning of a range of HPV types associated with both cancer precursors (cervical intraepithelial neoplasia or CIN) and carcinomas and extensive epidemiologic, clinical, pathologic, and experimental data. These accumulated results have culminated in new paradigms of cancer prevention through screening and triage. Despite this, the management of women with CIN is still suboptimal and the overtreatment of these conditions still occurs, largely due to the lack of clarity regarding which precancerous lesions are most likely to progress in grade. Recently, a discrete population of cuboidal cells was discovered at the cervical squamocolumnar junction, the anatomic site where the large majority of HPV-related (pre)neoplastic lesions develop. These cells seem to be embryonic in nature and participate both in benign metaplasias and the initial phase of precancer development. This review summarizes the historical evolution of precursor management, assesses the potential role of this and other discoveries in segregating lower from higher-risk precursors, and examines their potential impact on the management of women with real or potential cervical cancer precursors.

A human papilloma virus testing algorithm comprising a combination of the L1 broad-spectrum SPF10 PCR assay and a novel E6 high-risk multiplex type-specific genotyping PCR assay

Human papillomavirus (HPV) epidemiological and vaccine studies require highly sensitive HPV detection and genotyping systems. To improve HPV detection by PCR, the broad-spectrum L1-based SPF10 PCR DNA enzyme immunoassay (DEIA) LiPA system and a novel E6-based multiplex type-specific system (MPTS123) that uses Luminex xMAP technology were combined into a new testing algorithm. To evaluate this algorithm, cervical swabs (n = 860) and cervical biopsy specimens (n = 355) were tested, with a focus on HPV types detected by the MPTS123 assay (types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 6, and 11). Among the HPV-positive samples, identifications of individual HPV genotypes were compared. When all MPTS123 targeted genotypes were considered together, good overall agreement was found (κ = 0.801, 95% confidence interval [CI], 0.784 to 0.818) with identification by SPF10 LiPA, but significantly more genotypes (P < 0.0001) were identified by the MPTS123 PCR Luminex assay, especially for HPV types 16, 35, 39, 45, 58, and 59. An alternative type-specific assay was evaluated that is based on detection of a limited number of HPV genotypes by type-specific PCR and a reverse hybridization assay (MPTS12 RHA). This assay showed results similar to those of the expanded MPTS123 Luminex assay. These results confirm the fact that broad-spectrum PCRs are hampered by type competition when multiple HPV genotypes are present in the same sample. Therefore, a testing algorithm combining the broad-spectrum PCR and a range of type-specific PCRs can offer a highly accurate method for the analysis of HPV infections and diminish the rate of false-negative results and may be particularly useful for epidemiological and vaccine studies.

The role of human papillomavirus in nongenital cancers

Human papillomavirus (HPV), one of the most common sexually transmitted diseases worldwide, has an established role in the pathogenesis of genital malignancies such as cervical cancer. The virus has also been implicated in the oncogenesis of nongenital cancers including head and neck malignancies (specifically oropharyngeal cancers) as well as anal cancer. There is less clarity regarding its role in lung and esophageal cancers. Worldwide, the incidence and prevalence of HPV-associated oropharyngeal cancer has been increasing over time. These patients have improved outcomes compared with those with HPV-negative oropharyngeal cancers, and there is continued interest in designing treatments specifically for this HPV-positive subgroup. Clinicians continue to gain an understanding of HPV in anal cancers and the risk factors associated with infection and progression to malignancy. This has potential implications for the eventual screening of high-risk groups. While HPV vaccination is currently approved for the prevention of cervical cancer, it also has potential in the prevention of all HPV-associated malignancies. In this review, current understanding of the role of HPV in nongenital cancers is discussed, as well as future implications for treatment and prevention.

A review of clinical trials of human papillomavirus prophylactic vaccines

End of study analyses of the phase III trials of prophylactic human papillomavirus (HPV) virus-like particle (VLP) vaccines in young women are now largely completed. Two distinct vaccines were evaluated, Gardasil(®) (Merck & Co., Whitehouse Station, NJ USA) a quadrivalent vaccine containing VLPs of types 6, 11, 16 and 18 and Cervarix(®) (GlaxoSmithKline Biologicals, Rixensart, Belgium), a bivalent vaccine containing VLPs of types 16 and 18. Both vaccines exhibited excellent safety and immunogenicity profiles. The vaccines also demonstrated remarkably high and similar efficacy against the vaccine-targeted types for a range of cervical endpoints from persistent infection to cervical intraepithelial neoplasia grade 3 (CIN3) in women naïve to the corresponding type at the time of vaccination. However, protection from incident infection or disease from non-vaccine types was restricted, and the vaccines had no effect on prevalent infection or disease. Gardasil(®) also demonstrated strong protection against genital warts and vulvar/vaginal neoplasia associated with the vaccine types. In other trials, Gardasil(®) protected mid-adult women from incident infection and CIN caused by the vaccine types and protected men for incident infection, genital warts and anal intraepithelial neoplasia by the vaccine types. Cervarix(®) protected against vaccine-targeted anal infections in women in an end of study evaluation. For practical reasons, efficacy studies have not been conducted in the primary target populations of current vaccination programs, adolescent girls and boys. However, immunogenicity bridging studies demonstrating excellent safety and strong immune responses in adolescence, coupled with the documentation of durable antibody responses and protection in young adults, leads to an optimistic projection of the effectiveness of the vaccines in adolescent vaccination programs. Taken together, the excellent clinical trial results strongly support the potential of the vaccines as high value public health interventions and justify their widespread implementation to prevent anogenital HPV infections and their associated neoplasia. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Human papillomavirus vaccines: where do they fit in HIV-infected individuals?

Human papillomavirus (HPV) is the etiological agent for cervical cancer and a large majority of anal cancers worldwide. In 2006 two preventive vaccines against the HPV were approved by the US Food and Drug Administration and have since been approved in over 100 countries. HIV-infected populations are at an increased risk for HPV-related cancers. None of the efficacy trials for these vaccines included HIV-infected populations. However, studies in HIV-infected children and adult men show that the vaccine is safe and highly immunogenic. Studies evaluating the vaccine in HIV-infected women are in progress. Based on these studies, the American Council on Immunization Practices recommends HPV vaccination for all HIV-infected children and young adults up to age 26 years. HPV vaccine policies in resource-limited countries, many of which have a high prevalence of HIV infection, are still being developed. Future studies should examine the role of HPV vaccination for older HIV-infected adults who likely have ongoing HPV infection.

EUROGIN 2011 roadmap on prevention and treatment of HPV-related disease

The EUROGIN 2011 roadmap reviews the current burden of human papillomavirus (HPV)-related morbidity, as well as the evidence and potential practice recommendations regarding primary and secondary prevention and treatment of cancers and other disease associated with HPV infection. HPV infection causes ~600,000 cases of cancer of the cervix, vulva, vagina, anus and oropharynx annually, as well as benign diseases such as genital warts and recurrent respiratory papillomatosis. Whereas the incidence of cervical cancer has been decreasing over recent decades, the incidence of anal and oropharyngeal carcinoma, for which there are no effective screening programs, has been rising over the last couple of decades. Randomized trials have demonstrated improved efficacy of HPV-based compared to cytology-based cervical cancer screening. Defining the best algorithms to triage HPV-positive women, age ranges and screening intervals are priorities for pooled analyses and further research, whereas feasibility questions can be addressed through screening programs. HPV vaccination will reduce the burden of cervical precancer and probably also of invasive cervical and other HPV-related disease in women. Recent trials demonstrated that prophylactic vaccination also protects against anogenital HPV infection, anogenital intraepithelial lesions and warts associated with vaccine types, in males; and anal HPV infection and anal intraepithelial neoplasia in MSM. HPV-related oropharyngeal cancer could be treated less aggressively because of better survival compared to cancers of the oropharynx unrelated to HPV. Key findings in the field of cervical cancer prevention should now be translated in cost-effective strategies, following an organized approach integrating primary and secondary prevention, according to scientific evidence but adapted to the local situation with particular attention to regions with the highest burden of disease.

EUROGIN 2011 roadmap on prevention and treatment of HPV-related disease

The EUROGIN 2011 roadmap reviews the current burden of human papillomavirus (HPV)-related morbidity, as well as the evidence and potential practice recommendations regarding primary and secondary prevention and treatment of cancers and other disease associated with HPV infection. HPV infection causes ~600,000 cases of cancer of the cervix, vulva, vagina, anus and oropharynx annually, as well as benign diseases such as genital warts and recurrent respiratory papillomatosis. Whereas the incidence of cervical cancer has been decreasing over recent decades, the incidence of anal and oropharyngeal carcinoma, for which there are no effective screening programs, has been rising over the last couple of decades. Randomized trials have demonstrated improved efficacy of HPV-based compared to cytology-based cervical cancer screening. Defining the best algorithms to triage HPV-positive women, age ranges and screening intervals are priorities for pooled analyses and further research, whereas feasibility questions can be addressed through screening programs. HPV vaccination will reduce the burden of cervical precancer and probably also of invasive cervical and other HPV-related disease in women. Recent trials demonstrated that prophylactic vaccination also protects against anogenital HPV infection, anogenital intraepithelial lesions and warts associated with vaccine types, in males; and anal HPV infection and anal intraepithelial neoplasia in MSM. HPV-related oropharyngeal cancer could be treated less aggressively because of better survival compared to cancers of the oropharynx unrelated to HPV. Key findings in the field of cervical cancer prevention should now be translated in cost-effective strategies, following an organized approach integrating primary and secondary prevention, according to scientific evidence but adapted to the local situation with particular attention to regions with the highest burden of disease.

Impact of the HIV epidemic on the incidence rates of anal cancer in the United States

BACKGROUND

The risk of anal cancer is substantially increased in HIV-infected individuals. Thus, the HIV epidemic may have influenced the increasing anal cancer trends in the United States. We estimated the impact of the HIV epidemic on trends in anal cancer incidence in the United States during 1980-2005.

METHODS

Data on anal cancer cases with and without AIDS were obtained from the HIV/AIDS Cancer Match Study. The number of HIV-infected anal cancer cases without AIDS was estimated from the number of anal cancers occurring before diagnosis of AIDS. The proportion of anal cancer cases with HIV infection in the general population was calculated. We estimated temporal trends in the incidence rates of anal cancer in the general population overall and after exclusion of HIV-infected cancer cases by calculating annual percent changes and 95% confidence intervals (CIs) using a Joinpoint log-linear model. All incidence rates were standardized to the 2000 US population by age, sex, and race.

RESULTS

During 1980-2005, of the 20 533 estimated anal cancer cases, 1665 (8.1%) were HIV-infected. During 2001-2005, the proportion of anal cancer cases with HIV infection was the highest-1.2% (95% CI = 0.93 to 1.4%) among females and 28.4% (95% CI = 26.6 to 29.4%) among males. During 1980-2005, HIV infection did not have an impact on the trends in anal cancer among females (incidence rates increased by 3.3% [95% CI = 3.0 to 3.7%] annually overall, and by 3.3% [95% CI = 2.9 to 3.6%] annually without HIV-infected anal cancer cases) but had a strong impact on the trends in anal cancer among males (incidence rates increased by 3.4% [95% CI = 2.9 to 3.9%] annually overall, and by 1.7% [95% CI = 1.2 to 2.3%] annually without HIV infection).

CONCLUSION

During 1980-2005, the increasing anal cancer incidence rates in the United States were strongly influenced by the HIV epidemic in males but were independent of HIV infection in females.

Diagnosis, treatment, and prevention of anal cancer

Rare in the general population, anal cancer has reached epidemic proportions among HIV-infected men who have sex with men (MSM). These cancers are human papillomavirus (HPV)-associated, usually HPV type16, and are analogous to cervical cancer. At present, the rates of anal cancer in this group are 10-fold higher than that of cervical cancer occurring in women in the general population. Although there are no national guidelines for screening for anal intraepithelial dysplasia (AIN), many large HIV clinics are now performing anal cytologic screening in their at-risk patients. This paper outlines the current approach to screening for AIN and its management.

Epidemiology of cervical cancer in Colombia

Worldwide, cervical cancer is the third most common cancer in women, and the first or second most common in developing countries. Cervical cancer remains in Colombia the first cause of cancer mortality and the second cause of cancer incidence among women, despite the existence of screening programs during the last 3 decades. Bucaramanga, Manizales and Cali reported rates around 20 per 100,000and Pasto 27 per 100,000. The Cali cancer registry has reported a progressive decrease in the age standardized incidence and mortality rates of cervical cancer over the past 40 years. Reasons for the decline in incidence and mortality of cervical cancer are multiple and probably include: improvement in socio-economic conditions, decrease in parity rates and some effect of screening programs. Human papilloma Virus is the main cause of cervical cancer, HPV natural history studies have now revealed that HPVs are the commonest of the sexually transmitted infections in most populations. Most HPV exposures result in spontaneous clearance without clinical manifestations and only a small fraction of the infected persons, known as chronic or persistent carriers, will retain the virus and progress to precancerous and cancer. HPV 16 and 18 account for 70% of cervical cancer and the 8 most common types. (HPV 16, 18, 45, 33, 31, 52, 58 and 35) account for about 90% of cervical cancer. Case-control studies also allowed the identification of the following cofactors that acting together with HPV increase the risk of progression from HPV persistent infection to cervical cancer: tobacco, high parity, long term use of oral contraceptives and past infections with herpes simplex type 2 and Chlamydia trachomatis. The demonstration that infection with certain types of human papillomavirus (HPV) is not only the main cause but also a necessary cause of cervical cancer has led to great advances in the prevention of this disease on two fronts: (i) Primary prevention by the use of prophylactic HPV vaccines; and (ii) secondary prevention by increasing the accuracy of cervical cancer screening.

Understanding and learning from the success of prophylactic human papillomavirus vaccines

An estimated 5% of human cancers are caused by human papillomavirus (HPV) infections, and most of these cancers are of the cervix. Two prophylactic HPV vaccines that target the two most oncogenic virus types, HPV16 and HPV18, are now commercially available. In controlled clinical trials, the vaccines proved to be effective at preventing incident anogenital infection and the associated neoplastic disease that is induced by these virus types. Here, we highlight the specific aspects of HPV biology and vaccine composition that are likely to contribute to the efficacy of these vaccines, and we discuss how these particular features might or might not be relevant for the development of effective vaccines against other sexually transmitted viruses such as HIV and herpes simplex virus (HSV).

Prevalence of and risk factors for anal human papillomavirus infection among young healthy women in Costa Rica

BACKGROUND

Anal cancer is caused by human papillomavirus (HPV), yet little is known about anal HPV infection among healthy young women.

METHODS

A total of 2017 sexually active women in the control arm of an HPV-16/18 vaccine trial had a single anal specimen collected by a clinician at the 4-year study visit. Samples were tested for HPV by SPF(10) PCR/DEIA/LiPA(25), version 1.

RESULTS

A total of 4% of women had HPV-16, 22% had oncogenic HPV, and 31% had any HPV detected in an anal specimen. The prevalence of anal HPV was higher among women who reported anal intercourse, compared with those who did not (43.4% vs 28.4%; P< .001). Among women who reported anal intercourse, cervical HPV (adjusted odds ratio [aOR], 5.3 [95% confidence interval {CI}, 3.4-8.2]), number of sex partners (aOR, 2.2 [95% CI, 1.1-4.6] for ≥ 4 partners), and number of anal intercourse partners (aOR, 1.9 [95% CI, 1.1-3.3] for ≥ 2 partners) were independent risk factors for anal HPV detection. Among women who reported no anal intercourse, cervical HPV (aOR, 4.7 [95% CI, 3.7-5.9]), number of sex partners (aOR, 2.4 [95% CI, 1.7-3.4] for ≥ 4 partners), and report of anal fissures (aOR, 2.3 [95% CI, 1.1-4.8]) were associated with an increased odds of anal HPV detection.

CONCLUSION

Anal HPV is common among young women, even those who report no anal sex, and was associated with cervical HPV infection. Anal fissures in women who report never having had anal intercourse may facilitate HPV exposure.

CLINICAL TRIALS REGISTRATION

NCT00128661.

Epidemiology and clinical aspects of HPV in head and neck cancers

Human papillomavirus (HPV) infection is now established as a major etiologic factor for oropharyngeal cancers. Case-control studies conducted around the world show strong and consistent associations of markers of HPV exposure with risk of oropharyngeal cancers (range of odds ratios [OR] for oral oncogenic HPV infections = 3.6-230.0, ORs for HPV16 L1 antibodies = 2.3-182.0, and ORs for HPV16 E6/E7 antibodies = 9.2-231.0. HPV-positive oropharyngeal cancers are epidemiologically distinct from HPV-negative ones, and are characterized by younger age at onset, male predominance, and strong association with sexual behaviors. Importantly, HPV-positive oropharyngeal cancer patients have substantially improved outcomes (28-80 % reductions in the risk of death) than HPV-negative patients. Given the superior survival, younger age, and good performance status of HPV-positive oropharyngeal cancer patients, de-intensified therapies are currently being considered for this group of patients. Recent analyses of cancer registry data show dramatic increases in incidence of oropharyngeal cancers during the past 15-20 years in several parts of the world, highlighting the need for prevention strategies. If proven efficacious, currently available prophylactic HPV vaccines hold great promise for primary prevention of HPV-associated oropharyngeal cancers.

Anal human papillomavirus DNA in women at a colposcopy clinic

OBJECTIVES

To describe the type-specific prevalence of anal and cervical human papillomavirus (HPV) infections and the cytology in HIV-negative women without a history of cervical cancer, attending a colposcopy clinic. To examine if an HPV positive anal smear is related to anal pathology and consequently indicative for further examinations (high resolution anoscopy, anal biopsy).

STUDY DESIGN

From 149 consecutive women an anal swab and a cervical swab were taken, using the Cervex-Brush. The presence of 18 different HPV genotypes was determined using TaqMan-based real-time quantitative PCR targeting type-specific sequences of viral genes. From the fluid containing the cellular material, a liquid-based cytology sample was prepared of both collections with the robotic BD PrepStain Slide Processor. All slides were pre-screened by BD FocalPoint system and categorized from quintiles 1 to 5 and afterwards screened using targeted microscopic interpretation of selected suspicious fields using FocalPoint guided screening review stations. The 2001 Bethesda System Terminology was used for the anal slides.

RESULTS

Ninety-six anal samples and all 149 cervical samples were adequate. Overall presence of HPV in the anus was 56.3% and in the cervix 53.7%. Overall, cytological abnormalities were found in 10.8% of anal smears and in 32.8% of cervical smears. HPV genotypes were identified in 47 samples on both sites: partial or complete concordance was found in 85.1%. HPV types 6, 16 and 18 were found in 27.9% and in 26.6% of the anal and cervical samples, respectively. The top three HPV types in the anus were 16, 51 and 39; in the cervix 16, 39, 51 and 56 (a shared 3(rd) place). HPV type 11 was not found.

CONCLUSIONS

The presence of HPV genotypes is clearly multifocal in this study population of women attending a colposcopy clinic, with high concordance of genotypes. The number of anal HPV infections is high. Although cytological abnormalities are rare, the presence of HPV may lead to anal lesions later in life. From this perspective, complementary medical history and clinical examination of the anal region are advised.

Collaboration and team science: from theory to practice

Interdisciplinary efforts are becoming more critical for scientific discovery and translational research efforts. Highly integrated and interactive research teams share a number of features that contribute to their success in developing and sustaining their efforts over time. Through analysis of in-depth interviews with members of highly successful research teams and others who did not meet their goals or ended because of conflicts, we identified key elements that are critical for team success and effectiveness. There is no debate that the scientific goal sits at the center of the collaborative effort. However, supporting features need to be in place to avoid the derailment of the team. Among the most important of these is trust: without trust, the team dynamic runs the risk of deteriorating over time. Other critical factors of which both leaders and participants need to be aware include developing a shared vision, strategically identifying team members and purposefully building the team, promoting disagreement while containing conflict, and setting clear expectations for sharing credit and authorship. Self-awareness and strong communication skills contribute greatly to effective leadership and management strategies of scientific teams. While all successful teams share the characteristic of effectively carrying out these activities, there is no single formula for execution with every leader exemplifying different strengths and weaknesses. Successful scientific collaborations have strong leaders who are self-aware and are mindful of the many elements critical for supporting the science at the center of the effort.

Collaboration and team science: from theory to practice

Interdisciplinary efforts are becoming more critical for scientific discovery and translational research efforts. Highly integrated and interactive research teams share a number of features that contribute to their success in developing and sustaining their efforts over time. Through analysis of in-depth interviews with members of highly successful research teams and others who did not meet their goals or ended because of conflicts, we identified key elements that are critical for team success and effectiveness. There is no debate that the scientific goal sits at the center of the collaborative effort. However, supporting features need to be in place to avoid the derailment of the team. Among the most important of these is trust: without trust, the team dynamic runs the risk of deteriorating over time. Other critical factors of which both leaders and participants need to be aware include developing a shared vision, strategically identifying team members and purposefully building the team, promoting disagreement while containing conflict, and setting clear expectations for sharing credit and authorship. Self-awareness and strong communication skills contribute greatly to effective leadership and management strategies of scientific teams. While all successful teams share the characteristic of effectively carrying out these activities, there is no single formula for execution with every leader exemplifying different strengths and weaknesses. Successful scientific collaborations have strong leaders who are self-aware and are mindful of the many elements critical for supporting the science at the center of the effort.

Cervical, anal and oral HPV in an adolescent inner-city health clinic providing free vaccinations

Objectives

Published human papillomavirus (HPV) vaccine trials indicate efficacy is strongest for those naive to the vaccine-types. However, few high-risk young women have been followed and cervical HPV has been the predominant outcome measure.

Methods

We collected cervical and anal swabs, as well as oral rinse specimens from 645 sexually active inner-city young females attending a large adolescent health-clinic in New York City that offers free care and HPV vaccination. Specimens were tested for HPV-DNA using a MY09/MY11-PCR system. Type-specific prevalence of HPV at each anatomic site was compared for individuals by vaccination dose using generalized estimating equation logistic regression models.

Results

The majority of subjects reported being of non-Caucasian (92%) and/or Hispanic ethnicity (61%). Median age was 18 years (range:14–20). All had practiced vaginal sex, a third (33%) practiced anal sex, and most (77%) had also engaged in oral sex. At enrollment, 21% had not received the vaccine and 51% had received three doses. Prevalent HPV infection at enrollment was detected in 54% of cervical, 42% of anal and 20% of oral specimens, with vaccine types present in 7%, 6% and 1% of specimens, respectively. Comparing prevalence for vaccine types, the detection of HPV in the cervix of vaccinated compared to unvaccinated adolescents was significantly reduced: HPV6/11 (odds ratio [OR] = 0.19, 95%CI:0.06–0.75), HPV16 (OR = 0.31, 95%CI:0.11–0.88) and HPV18 (OR = 0.14, 95%CI:0.03–0.75). For anal HPV, the risk of detecting vaccine types HPV6/11 (OR = 0.27, 95%CI:0.10–0.72) and HPV18(OR = 0.12, 95%CI:0.01–1.16) were significantly reduced for vaccinated adolescents however, the risk for HPV16 was not significantly decreased (OR = 0.63, 95%CI:0.18–2.20).

Conclusion

HPV Prevalence is extremely high in inner-city female adolescents. Administration of the HPV vaccine reduced the risk for cervical HPV; however continued follow-up is required to assess the protection for HPV at all sites in young women with high exposure.

Cancers that U.S. physicians believe the HPV vaccine prevents: findings from a physician survey, 2009

BACKGROUND

There is strong scientific evidence that human papillomavirus (HPV) vaccines, which protect against two oncogenic HPV types (16 and 18), can prevent cervical, vaginal, and vulvar cancers in women. In addition, recent research has established that the HPV vaccine can prevent anal cancer and has implied that it may also prevent oropharyngeal cancers.

METHODS

A 2009 web-based survey of 1500 physicians from four specialties (pediatricians, family practitioners, internists, and obstetrician-gynecologists) explored knowledge about which female cancers the HPV vaccine was effective in preventing. Physician characteristics associated with the belief that the HPV vaccine prevents cervical, vaginal, vulvar, anal, and other cancers were examined using logistic regression models.

RESULTS

Nearly all respondents (97.8%) identified cervical cancer as being prevented by the HPV vaccine; however, lower awareness that the vaccine prevents vaginal (23.8%), vulvar (27.8%), and anal cancer (28.4%) was found. Physician specialty was the most significant covariate identified, with obstetrician-gynecologists being more likely than other physicians to report that the HPV vaccine protected against vaginal (p<0.001), vulvar (p<0.001), and anal (p<0.001) cancers.

CONCLUSIONS

Physicians may benefit from educational efforts clarifying which noncervical cancers can be prevented by the HPV vaccine. Education is needed across all medical specialties, but it is particularly important for pediatricians and family practitioners, the physicians most likely to administer the HPV vaccine to young adolescents.

Risk of anal cancer in HIV-infected and HIV-uninfected individuals in North America

BACKGROUND

Anal cancer is one of the most common cancers affecting individuals infected with human immunodeficiency virus (HIV), although few have evaluated rates separately for men who have sex with men (MSM), other men, and women. There are also conflicting data regarding calendar trends.

METHODS

In a study involving 13 cohorts from North America with follow-up between 1996 and 2007, we compared anal cancer incidence rates among 34 189 HIV-infected (55% MSM, 19% other men, 26% women) and 114 260 HIV-uninfected individuals (90% men).

RESULTS

Among men, the unadjusted anal cancer incidence rates per 100 000 person-years were 131 for HIV-infected MSM, 46 for other HIV-infected men, and 2 for HIV-uninfected men, corresponding to demographically adjusted rate ratios (RRs) of 80.3 (95% confidence interval [CI], 42.7-151.1) for HIV-infected MSM and 26.7 (95% CI, 11.5-61.7) for other HIV-infected men compared with HIV-uninfected men. HIV-infected women had an anal cancer rate of 30/100 000 person-years, and no cases were observed for HIV-uninfected women. In a multivariable Poisson regression model, among HIV-infected individuals, the risk was higher for MSM compared with other men (RR, 3.3; 95% CI, 1.8-6.0), but no difference was observed comparing women with other men (RR, 1.0; 95% CI, 0.5-2.2). In comparison with the period 2000-2003, HIV-infected individuals had an adjusted RR of 0.5 (95% CI, .3-.9) in 1996-1999 and 0.9 (95% CI, .6-1.2) in 2004-2007.

CONCLUSIONS

Anal cancer rates were substantially higher for HIV-infected MSM, other men, and women compared with HIV-uninfected individuals, suggesting a need for universal prevention efforts. Rates increased after the early antiretroviral therapy era and then plateaued.

Time for a strategic research response to anal cancer

Anal cancer was until recently regarded as a rare cancer of little consequence. The articles in this special edition of Sexual Health clearly demonstrate that anal cancer is increasing in incidence and, in some populations, it has become an urgent public health priority. In this summary paper, we will review the data presented in this issue and elsewhere on the magnitude of the issue, the means of prevention and treatment, and suggest a way forward.

The epidemiology of anal human papillomavirus infection among women and men having sex with women

The goal of this review is to summarise epidemiological data that support an understanding of the natural history of anal human papillomavirus (HPV) among women and men having sex with women (MSW). HPV is a common infection of the anal canal among women and MSW. Although there have been a limited number of studies to date, both oncogenic and nononcogenic HPV genotypes commonly occur among these populations even when individuals do not report receptive anal sex. Genotype distribution is quite diverse, with recent studies typically detecting more than two dozen genotypes in the anal canal in samples of women and MSW. Factors most consistently associated with HPV in the anal canal among both women and MSW are lifetime number of sexual partners and detection of HPV at the genitals. The common finding of genotypic concordance between the genitals and anal canal in women and MSW, and the infectious nature of HPV, in addition to a limited number of studies offering empirical evidence of anal-to-genital self-inoculation and evidence of HPV hand carriage, may help explain the detection of HPV in the anal canal outside the context of receptive anal sex. HPV vaccination has been shown to reduce anal HPV infection among women and is also a promising prevention strategy among MSW.

Next Generation Cancer Protection: The Bivalent HPV Vaccine for Females

Nearly a half a million women throughout the world develop cervical cancer every year Parkin and Bray ("Chapter 2. The burden of HPVrelated cancers," Vaccine, vol. 24, no. 3, pp. S11-S25, 2006); 80% of these women are in countries without a quality-assured cytology screening program. It is in this setting that Cervarix could reduce the incidence of cervical cancer to about 9.5/100,000 women. New evidence indicates that this might be able to be accomplished with a single dose of Cervarix, a great advantage to public health implementation programs Kreimer et al. ("Proof-of-principle evaluation of the efficacy of fewer than three doses of a bivalent HPV16/18 vaccine, The Journal of the National Cancer Institute, vol. 103, no. 19, pp. 1444-1451, 2011). In countries with screening programs, adenocarcinoma is the most difficult to detect and treat with later-stage presentation and higher mortality Smith et al. ("The rising incidence of adenocarcinoma relative to squamous cell carcinoma of the uterine cervix in the United States-a 24-year population-based study," Gynecologic Oncology, vol. 78, no. 2, pp. 97-105, 2000) and Gunnell et al. ("A longitudinal Swedish study on screening for squamous cell carcinoma and adenocarcinoma: evidence of effectiveness and overtreatment," Cancer Epidemiology Biomarkers and Prevention, vol. 16, no. 12, pp. 2641-2648, 2007). With additional cross-protection to HPV 31, 33, and 45 and protection against HPV 16 and 18 lasting at least 9.4 years, Cervarix may reduce adenocarcinomas in screened populations by more than 90%. This paper will detail the evidence about the efficacy, immunogenicity, and safety of Cervarix in the studied populations contrasting public health goals with individual health options.

Comparing bivalent and quadrivalent human papillomavirus vaccines: economic evaluation based on transmission model

OBJECTIVES

To compare the effect and cost effectiveness of bivalent and quadrivalent human papillomavirus (HPV) vaccination, taking into account differences in licensure indications, protection against non-vaccine type disease, protection against disease related to HPV types 6 and 11, and reported long term immunogenicity.

DESIGN

A model of HPV transmission and disease previously used to inform UK vaccination policy, updated with recent evidence and expanded to include scenarios where the two vaccines differ in duration of protection, cross protection, and end points prevented.

SETTING

United Kingdom. Population Males and females aged 12-75 years.

MAIN OUTCOME MEASURE

Incremental cost effectiveness ratios for both vaccines and additional cost per dose for the quadrivalent vaccine to be equally cost effective as the bivalent vaccine.

RESULTS

The bivalent vaccine needs to be cheaper than the quadrivalent vaccine to be equally cost effective, mainly because of its lack of protection against anogenital warts. The price difference per dose ranges from a median of £19 (interquartile range £12-£27) to £35 (£27-£44) across scenarios about vaccine duration, cross protection, and end points prevented (assuming one quality adjusted life year (QALY) is valued at £30,000 and both vaccines can prevent all types of HPV related cancers).

CONCLUSIONS

The quadrivalent vaccine may have an advantage over the bivalent vaccine in reducing healthcare costs and QALYs lost. The bivalent vaccine may have an advantage in preventing death due to cancer. However, considerable uncertainty remains about the differential benefit of the two vaccines.