Systematic review of human papillomavirus prevalence in invasive penile cancer

The predicted impact of HPV vaccination on male infections and male HPV-related cancers in Australia

Australia implemented a National HPV Vaccination Program in 2007, with routine vaccination of 12-13 year old females and catch-up in females aged 13-26 years to 2009. The aim of this study was to estimate the impact of the current female-only national vaccination program on males, and then to estimate the incremental benefits to males from being included in the program. We used preliminary data to estimate vaccination coverage in females. We then fitted a dynamic model of sexual behaviour and HPV transmission in Australia to local data on female pre-vaccination age-specific HPV prevalence, predicted the corresponding pre-vaccination prevalence in males due to heterosexual transmission, and modelled the short and long term impact of female-only versus female-and-male vaccination programs. The estimated 3-dose female coverage rates were 78% (range 70-80%) for ongoing coverage in 12-13 year old girls; and from 74% (range 70-80%) in 14 year olds, to 25% (range 15-35%) for women aged 26 years old in 2007. The median estimate for age-standardised pre-vaccination HPV 16 prevalence in females and males aged 15-59 years was 3.2% (95% range: 2.4-4.1%) and 3.1% (95% range: 2.2-4.2%), respectively. The current program in females is predicted to result in a 68% reduction in male HPV 16 infections by 2050, leading to an estimated long term reduction of 14% in rates of cancers of the head, neck and anogenital area. The estimated proportion of the maximum possible vaccine-conferred benefit to males from a female-and-male program which will be achieved by female-only vaccination is 73% (range in probabilistic sensitivity analysis: 53-78%). In conclusion, up to three-quarters of the maximum possible vaccination-conferred benefit to males due to reduced heterosexual transmission will be achieved by the existing female-only program.

[AIDS Study Group/Spanish AIDS Consensus Plan Document on sexually transmitted infections in HIV-infected patients]

Sexually transmitted infections (STI) are a major public health problem. Considering their high morbidity and potential short and long term after effects, physicians must have enough knowledge on the management of these infections for a correct prevention, diagnosis and treatment. HIV infection is associated with STI, not only because they share route of transmission, but also because they lead to an increased risk of HIV transmission. In this article, we summarise the updated clinical practice guidelines, for the evaluation, management and prevention of STI in HIV-infected patients, from a panel of experts in HIV, dermatologists, proctologic surgeons, and microbiologists on behalf of the Spanish AIDS Study Group (GESIDA) and the National AIDS Plan (PNS).

Alternative HER/PTEN/Akt pathway activation in HPV positive and negative penile carcinomas

Background

The pathogenesis of penile squamous cell carcinoma (PSCC) is not well understood, though risk factors include human papillomavirus (HPV). Disruption of HER/PTEN/Akt pathway is present in many cancers; however there is little information on its function in PSCC. We investigated HER family receptors and phosphatase and tension homolog (PTEN) in HPV-positive and negative PSCC and its impact on Akt activation using immunohistochemistry and fluorescent in situ hybridisation (FISH).

Methodology/Principal Findings

148 PSCCs were microarrayed and immunostained for phosphorylated EGFR (pEGFR), HER2, HER3, HER4, phosphorylated Akt (pAkt), Akt1 and PTEN proteins. EGFR and PTEN gene status were also evaluated using FISH. HPV presence was assessed by PCR. pEGFR expression was detected significantly less frequently in HPV-positive than HPV-negative tumours (p = 0.0143). Conversely, HER3 expression was significantly more common in HPV-positive cases (p = 0.0128). HER4, pAkt, Akt and PTEN protein expression were not related to HPV. HER3 (p = 0.0054) and HER4 (p = 0.0002) receptors significantly correlated with cytoplasmic Akt1 immunostaining. All three proteins positively correlated with tumour grade (HER3, p = 0.0029; HER4, p = 0.0118; Akt1, p = 0.0001). pEGFR expression correlated with pAkt but not with tumour grade or stage. There was no EGFR gene amplification. HER2 was not detected. PTEN protein expression was reduced or absent in 62% of tumours but PTEN gene copy loss was present only in 4% of PSCCs.

Conclusions/Significance

EGFR, HER3 and HER4 but not HER2 are associated with penile carcinogenesis. HPV-negative tumours tend to express significantly more pEGFR than HPV-positive cancers and this expression correlates with pAkt protein, indicating EGFR as an upstream regulator of Akt signalling in PSCC. Conversely, HER3 expression is significantly more common in HPV-positive cases and positively correlates with cytoplasmic Akt1 expression. HER4 and PTEN protein expression are not related to HPV infection. Our results suggest that PSCC patients could benefit from therapies developed to target HER receptors.

Equine penile squamous cell carcinomas are associated with the presence of equine papillomavirus type 2 DNA sequences

Forty cases of equine penile disease were screened with polymerase chain reaction for the presence of papillomaviral DNA. Cases consisted of 20 squamous cell carcinomas (average age of horse, 23.9 years) and 20 non-squamous cell carcinoma diseases (average age of horse, 13.3 years). All horses but one originated from the Northeastern United States. Breeds were not recorded. As based on MY09/MY11 consensus primers, DNA sequences from equine papillomavirus type 2 were amplified from 9 of 20 horses (45%) with penile squamous cell carcinoma and only 1 of 20 horses (5%) with non-squamous cell carcinoma penile disease. Equine papillomavirus type 2 DNA was the only papillomaviral DNA amplified from any of the 40 horses. Tissues from the 10 horses in which papillomaviral DNA was detected by polymerase chain reaction were also screened with in situ hybridization and immunohistochemistry. The presence of papillomavirus was demonstrated in a subset of these by in situ hybridization (6 of 10) and immunohistochemistry (1 of 10). This report describes a possible association between equine penile squamous cell carcinomas and equine papillomavirus type 2. This study is also the first report of equine papillomavirus type 2 infection in North American horses.

Cancers attributable to human papillomavirus infection

Although the human papillomavirus (HPV) vaccine was introduced primarily as a cervical cancer prevention vaccine, HPV has a causal role in several types of cancer. This article reviews the epidemiological evidence for the role of HPV in human cancer, and describes Australian trends in these cancers. HPV is a necessary cause of cervical cancer. The currently vaccine-preventable subtypes of HPV 16 and 18 are responsible for ~70% of cervical cancer. The introduction of an organised Pap smear program in Australia led to a steep decline in incidence over the past decades. HPV can be detected in ~40% and 70% of vulval and vaginal cancers respectively. Rates of these cancers have been stable over the past 20 years. The prevalence of HPV in penile cancer is ~50% and incidence has not recently changed. For anal cancer, ~85% of cases are HPV positive, and incidence has increased significantly in both men and women over the past 20 years. In the oral cavity, ~35% of oropharyngeal cancers and ~25% of other oral cavity cancers are HPV positive. The incidence of HPV-related oral cavity and oropharyngeal cancers is increasing, whereas incidence at HPV-unrelated sites is decreasing. Overall, 1154 HPV-related cancer cases were potentially preventable by vaccination. If HPV-related cancers at non-cervical sites are prevented by vaccination, then a similar number of cancer cases will be prevented as in the cervix. However, almost one-quarter of the potentially preventable cancer cases are in men, who are not included in the current national immunisation program.

Human papillomavirus prevalence, distribution and correlation to histopathological parameters in a large Swedish cohort of men with penile carcinoma

OBJECTIVE

• To analyse the overall and type-specific human papillomavirus (HPV) prevalence and distribution in penile carcinoma and determine the correlation to histopathological parameters.

PATIENTS AND METHODS

• In this retrospective study, we analysed HPV status in 241 patients with penile carcinoma, treated at Örebro University Hospital, Örebro, Sweden, between 1984 and 2008. Age and date at diagnosis was recorded. • The tumour specimens were categorized according to the UICC 2002 TNM classification. A subset of patients was operatively staged with regard to lymph node status. • A commercially available Real Time PCR was used to detect 13 different types of HPV (6,11,16,18,31,33,35,45,51,52,56,58 and 59).

RESULTS

• We excluded 25 patients due to low DNA quality. Of the remaining 216, 179 (82.9%) tumour specimens were HPV infected. The majority of cases positive for HPV (70.4%) were infected by a single-type. The most frequent type was HPV 16 followed by HPV 18. • No significant association between HPV status and pathological tumour stage, grade or lymph node status was found.

CONCLUSION

• The HPV prevalence found is higher than in most other studies, further strengthening HPV as an etiological agent in penile carcinoma. Furthermore, the high prevalence of HPV 16 and 18 raises the question of what potential impact current HPV vaccines that target these specific HPV types might have on penile carcinoma. No significant association between HPV status and histopathological parameters was found in the present study. Additional investigations are needed to draw final conclusions on the prognostic value of HPV status in penile carcinoma.

Human papillomavirus vaccines: current status and future prospects

Worldwide, cervical cancer is the second most common cancer of women. Less-developed countries bear the greatest burden in terms of morbidity and mortality, largely due to the lack of organized screening programmes. Cervical cancer is the first cancer shown to be caused solely by virological agents: oncogenic genotypes of human papillomavirus (HPV). Two recently developed prophylactic cervical cancer vaccines, which are based on viral-like particle (VLP) technology of HPV, have the capacity to diminish a large proportion of cervical cancer cases worldwide. However, to be successful public health tools, they need to be widely implemented to the appropriate target population, preferably prior to first sexual intercourse. To increase vaccination coverage, national programmes in some countries have also included catch-up vaccination, for a limited time period, to young adult women aged up to 26 years. Despite the excellent efficacy for high-grade dysplasia due to vaccine-related HPV types (near to 100%) and immunogenicity induced against the HPV types 16 and 18 in females naive to those HPV types pre-vaccination, some form of cervical precancer screening will still be necessary. Immunity to HPV is primarily type specific, and thus protection induced by the current generation of vaccines, based on a limited number of HPV VLP types, cannot provide complete protection against all oncogenic HPV types. Both these vaccines translate to protection of cervical cancer in the order of 70-75%, which represents the percentage of invasive cancers attributable to HPV-16 and -18. Challenges to ensuring the successful control of this largely preventable disease include endorsement by governments and policy makers, affordable prices, education at all levels, overcoming barriers to vaccination and continued adherence to screening programmes.

Trends in survival of patients diagnosed with male genital cancers in the Nordic countries 1964-2003 followed up until the end of 2006

BACKGROUND

Prostate, testicular and penile cancer constitute about one-third of the cancer incidence burden among Nordic males, but less than one-fifth of the corresponding mortality. The aim of this study is to describe and interpret trends in relative survival and excess mortality in the five Nordic populations.

MATERIAL AND METHODS

Age-standardised incidence and mortality rates, 5-year relative survival, and excess mortality rates for varying follow-up periods are presented, as are age-specific 5-year relative survival by country, sex and 5-year diagnostic period.

RESULTS

The vast majority of male genital cancer incident cases and deaths are prostate cancers, with 5-year and 10-year survival trends resembling the diagnostic-led increasing incidence over the past 25 years. Five-year prostate cancer survival is estimated at 53% in Denmark compared to 78% or above in the other Nordic populations for patients diagnosed 1999-2003. Excess mortality has declined over time, with Denmark having a greater excess of deaths compared to the other countries, irrespective of time of diagnosis. Concomitant with the declines in testicular cancer mortality, testicular cancer survival has increased since the 1970s in each Nordic country. Men diagnosed with testicular cancer in recent decades have had, on average, a continually better prognosis with time, with relative 5-year survival for patients diagnosed 1999-2003 ranging from 88% in Finland to 94% in Sweden. For the few patients diagnosed with cancer of the penis and other male genital organs, survival trends have been rather stable over time, with recent 5-year relative survival estimates ranging from 62% in Finland to 80% in Norway.

CONCLUSIONS

There are intriguing country-specific and temporal variations in male genital cancer survival in the Nordic countries. Prognosis varies widely by cancer site and relates to both changing diagnostic and clinical practices. The increasing PSA detection and biopsy makes interpretation of the prostate cancer survival trends particularly difficult.

Prevalence and risk factors of human papillomavirus infection by penile site in uncircumcised Kenyan men

Human papillomavirus (HPV) prevalence was estimated from 2,705 sexually active, uncircumcised, human immunodeficiency virus seronegative men aged 17-28 years in Kisumu, Kenya. HPV prevalence was 51.1% (95% confidence interval: 49.2-53.0%) in penile cells from the glans/coronal sulcus and/or shaft. HPV prevalence varied by anatomical site, with 46.5% positivity in the glans/coronal sulcus compared with 19.1% in the shaft (p < 0.0001). High-risk HPV was detected in 31.2% of glans and 12.3% of shaft samples (p < 0.0001). HPV16 was the most common type and 29.2% of men were infected with more than one HPV type. Risk factors for HPV infection included presence of C. trachomatis, N. gonorrhea, self-reported sexually transmitted infections, and less frequent bathing. Lifetime number of sexual partners and herpes simplex virus type-2 seropositivity were also marginally associated with HPV infection.

Comparison of Subtypes of Penile Squamous Cell Carcinoma From High and Low Incidence Geographical Regions

There is a worldwide geographical variation in the incidence of penile squamous cell carcinoma (PSCC); some subtypes are HPV-related (warty, basaloid) while others (keratinizing variants) are not. The aims of this study were to compare the distribution of different histological subtypes of PSCC from regions of low (Paraguay, 144 cases) and high (USA, 157 cases) incidence and to identify and compare tumors with and without warty and/or basaloid morphology. The distribution of subtypes in the Paraguayan and the American series was: usual, 49.3 and 46.5%; verrucous, 8.3 and 7.6%; papillary NOS, 7.6 and 5.7%; warty, 6.9 and 8.3%; basaloid, 4.2 and 7.0%; sarcomatoid, 0.7 and 0.6%; adenosquamous, 3.5 and 0.6%; and mixed, 19.4 and 23.6%, respectively. The distribution of mixed PSCC was: warty-basaloid, 50.0 and 59.5%; usual-verrucous, 21.4 and 21.6%; usual-warty, 14.3 and 8.1%; usual-basaloid, 7.1 and 0.0%; usual-papillary, 3.6 and 5.4%; and others, 3.6 and 5.4%, respectively. In conclusion, we found no geographical difference in the incidence of histological subtypes ( p = 0.6501), mixed PSCC ( p = 0.5937) or HPV-related tumors ( p = 0.2505). Geographical variation may be the result of staging variation at clinical presentation or of pathological diagnosis. The identification of similar histological subtypes in both series validates this classification approach for penile cancer. The tendency for typical SCC to mix with verrucous and papillary carcinomas and of the basaloid to preferentially mix with benign condyloma and condylomatous (warty) carcinomas would support the hypothesis of the existence of an etiologically different dual population of penile tumors.

Evaluating the impact of human papillomavirus vaccines

While two prophylactic HPV vaccines have been proven notably efficacious in clinical trials, the effectiveness of these vaccines at the population level remains to be evaluated. To lay the foundation for understanding the strengths and limitations of different endpoints for future effectiveness research, we present a comprehensive review of HPV-related clinical outcomes, including: (i) HPV type-specific positivity and persistence, (ii) Pap diagnoses (ASC-US, LSIL, and HSIL), (iii) histologic cervical cancer precursor lesions (i.e., CIN1, CIN2, and CIN3), (iv) invasive cervical cancer (ICC), (v) anogenital warts, (vi) recurrent respiratory papillomatosis (RRP), and (vii) other HPV-associated cancers (vulvar, vaginal, anal, penile, and oropharyngeal). While research on the vaccines' effects on these HPV clinical outcomes in the general population is presently limited, numerous large trials will soon be completed, making a priori discussion of these potential outcomes especially urgent. Furthermore, population level systems to track HPV-associated clinical outcomes may need to be developed for HPV vaccine effectiveness evaluation.