Comparison of hybrid capture II, linear array, and a bead-based multiplex genotyping assay for detection of human papillomavirus in women with negative pap test results and atypical squamous cells of undetermined significance

Prevalence of human papillomavirus types in head and neck cancer sub-sites in the Indian population

Although a subset of head and neck cancers (HNC) has been associated worldwide with mucosal high-risk human papillomaviruses (HPV), information on the prevalence of HPV-positive HNC in India is limited. In this study, we examined the prevalence of 21 subtypes of HPV in sub-sites of HNC (n = 175) in the western region of India. Type-specific multiplex genotyping assay was conducted at the Centre for Cancer Epidemiology, Tata Memorial Centre, to determine the prevalence of HPV subtypes. The HPV prevalence was observed to be 28.43%, 41.67%, 38.89% and 15.79% in the oral cavity, oropharynx, hypopharynx and larynx tumour tissues, respectively. The HPV 16 genotype was most common in all HNC tumour tissues (30.29%), followed by HPV 58 (0.57%).

Acquisition, prevalence and clearance of type-specific human papillomavirus infections in young sexually active Indian women: A community-based multicentric cohort study

In context of the ongoing multi-centric HPV vaccine study in India, unvaccinated married women (N = 1484) aged 18-23 years were recruited in 2012-2015 as age-matched controls to the vaccinated women and followed up yearly. We assess type-specific prevalence, natural history and potential determinants of human papillomavirus (HPV) infection in these unvaccinated women. Cervical samples were collected yearly for at least four consecutive years. A Multiplex Type-Specific E7-Based polymerase chain reaction assay was used to detect 21 HPV types. HPV prevalence was 36.4% during 6 years. Most common HPV types were 16 (6.5%) and 31 (6.1%). Highest persistence were observed for HPV 35 (62.5%) and 52 (25%). New HPV acquisition rate was 5.6/1000 person-months of observation (PMO), highest for HPV 16 (1.1/1000 PMO). Type-specific clearance rates ranged between 2.9-5.5/100 PMO. HPV 16 and/or 18 infections were 41% (95% CI 4-63%) lower among women with 2-<3 years between marriage and first cervical sample collection compared to those with <2 years. HPV prevalence and acquisition rates in young Indian women were lower than their Western counterparts. HPV 16 infections being most common shows the importance and potential impact of HPV vaccination in India. Women with 2-3 years exposure had reduced risk possibly due to higher infections clearance.

Development and validation of a protocol for optimizing the use of paraffin blocks in molecular epidemiological studies: The example from the HPV-AHEAD study

Worldwide use of formalin-fixed paraffin-embedded blocks (FFPE) is extensive in diagnosis and research. Yet, there is a lack of optimized/standardized protocols to process the blocks and verify the quality and presence of the targeted tissue. In the context of an international study on head and neck cancer (HNC)-HPV-AHEAD, a standardized protocol for optimizing the use of FFPEs in molecular epidemiology was developed and validated. First, a protocol for sectioning the FFPE was developed to prevent cross-contamination and distributed between participating centers. Before processing blocks, all sectioning centers underwent a quality control to guarantee a satisfactory training process. The first and last sections of the FFPEs were used for histopathological assessment. A consensus histopathology evaluation form was developed by an international panel of pathologists and evaluated for four indicators in a pilot analysis in order to validate it: 1) presence/type of tumor tissue, 2) identification of other tissue components that could affect the molecular diagnosis and 3) quality of the tissue. No HPV DNA was found in sections from empty FFPE generated in any histology laboratories of HPV-AHEAD consortium and all centers passed quality assurance for processing after quality control. The pilot analysis to validate the histopathology form included 355 HNC cases. The form was filled by six pathologists and each case was randomly assigned to two of them. Most samples (86%) were considered satisfactory. Presence of >50% of invasive carcinoma was observed in all sections of 66% of cases. Substantial necrosis (>50%) was present in <2% of samples. The concordance for the indicators targeted to validate the histopathology form was very high (kappa > 0.85) between first and last sections and fair to high between pathologists (kappa/pabak 0.21-0.72). The protocol allowed to correctly process without signs of contamination all FFPE of the study. The histopathology evaluation of the cases assured the presence of the targeted tissue, identified the presence of other tissues that could disturb the molecular diagnosis and allowed the assessment of tissue quality.

Comparison of the analytical and clinical performance of five tests for the detection of human papillomavirus genital infection

HPV-based screening provides greater protection against cervical cancer (CC) than cytology-based strategies. Currently, several molecular diagnostic assays for the detection of human papillomavirus (HPV) are available. In this study, we analyzed 5 different HPV testing and genotyping techniques (Hybrid Capture 2 [HC2; Qiagen, Hilden, Germany], AnyplexTMII HPV28 [Anyplex; Seegene, Seoul, Korea], Linear Array [Roche, Branchburg, NJ, USA], GP5+/6+ PCR-EIA-RH [Labo Bio-medical Products, Rijswijk, The Netherlands] and CLART2 [Genomica, Madrid, Spain]) in 295 women referred to the hospital Colposcopy Clinic from 2007 to 2008 due to positive HPV test results or an abnormal Pap test. DNA extraction for HPV genotyping was performed in cervical sample specimens after Pap test and HPV detection by HC2. The inclusion criteria were: (1) adequate cervical sampling with sufficient material for the Pap test and HPV detection and genotyping, and (2) colposcopically-directed biopsy and/or endocervical curettage. HC2 showed the highest sensitivity for high-grade squamous intraepithelial lesion and CC (HSIL+) detection (96.1%), but all the HPV genotyping tests showed a higher specificity. (Anyplex 86.8%; Linear Array 86.0%; GP5+/6+ 78.8%; CLART2 76.5%). The agreement between HC2 results and the other techniques was similar: 82.4%, kappa=0.650 for Anyplex; 83.4%, kappa=0.670 for Linear Array, 79.93%, kappa=0.609 for GP5+/6+ and 82.4%, kappa=0.654 for CLART2. HPV 16 and/or 18 infection was a risk factor for underlying HSIL+ in the univariate analysis. Anyplex showed the highest risk of underlying HSIL+ after positive HPV 16 and/or 18 tests (OR 31.1; 95% CI 12.1-80.0).

Chlamydia trachomatis and HPV co-infections in HIV negative men from a multi-ethnic area of Northern Italy at high prevalence of cervical malignancies

Chlamydia trachomatis and HPV coinfections in the male population are often a disregarded issue. We performed a study to evaluate the prevalence of such infections in heterosexual HIV negative men from a Northern Italy multi-ethnic area at high prevalence for cervical malignancies. Urethral swabs (US) or first-voided urine were evaluated retrospectively from 1317 patients attending Sexually Transmitted Infections (STI) clinic and from 3388 outpatients attending private clinics. Informations about participants' demographic characteristics and attributes of C. trachomatis, including chronic infection, and HPV genotypes testing, were collected. Exact Fisher test, bivariate, and multivariate logistic regressions were carried out. The prevalence of C. trachomatis was 1.7% in the outpatients and 16.9% in the STI group (P < 0.0001) in which the highest frequency was observed in men of age ≤25 years. Among patients with C. trachomatis, asymptomatic HPV co-infection was detected in 33% of men from the STI clinic and in 2% of the outpatients. Out of all coinfections, 56% were due to single HPV, with a prevalence of 73% in young STI men. The distribution of HPV genotypes confirmed the increased circulation of LR-HPV42, HR-HPV51, HR-HPV52 and prHR-HPV82, and the decreasing of HR-HPV16. African nationalities and leucorrhea were significantly associated risk factors, while the regular condom use offered an effective protection. This study highlights the high prevalence of C. trachomatis and HPV asymptomatic co-infection in young HIV negative men attending the STI clinic, representing a reservoir of new HPV genotypes with potential oncogenic risk.

HPV genotypes distribution in Chlamydia trachomatis co-infection in a large cohort of women from north-east Italy

Human papillomavirus (HPV) and Chlamydia trachomatis are pathogens with oncogenic potential associated with persistent infections. Epidemiological data on C. trachomatis infection status, C. trachomatis/HPV co-infection and the relationship between HPV genotypes in Italian women are only preliminary. The aim of the present study was to characterize the relationship between HPV genotypes and C. trachomatis in an extending cohort of asymptomatic immunocompetent women from an area of north-east Italy. A retrospective study was conducted using Luminex technology on cervical swabs from asymptomatic immunocompetent women, comprising 921 attending the prevention centre for the Cervical Cancer Program and 6214 who had been referred to the Sexually Transmitted Infections Center, with clinical indications of HPV and C. trachomatis infections. A quantitative real-time PCR was performed to assess chronic C. trachomatis infection by heat-shock protein 60 (Hsp60) gene expression. The overall prevalence of the investigated pathogens was 39 % (359/921) for HPV and 4 % (251/6214) for C. trachomatis. The Hsp60 gene was detected in 57 % of the women infected with C. trachomatis. HPV co-infection was present in 58 % of C. trachomatis-infected women. A high prevalence of co-infection was found in women with chronic C. trachomatis infection (68 %, P = 0.0002), especially in women ≤ 25 years (72 %) where HPV multiple infections were found in 78 % (P = 0.022). HPV genotype distribution showed that uncommon low-risk genotypes were associated with C. trachomatis. These results indicate a high frequency of co-detection of multiple HPV genotypes in chronically infected young women and suggest that the expression of the C. trachomatis Hsp60 gene may favour HPV infection.

Association Study between Cervical Lesions and Single or Multiple Vaccine-Target and Non-Vaccine Target Human Papillomavirus (HPV) Types in Women from Northeastern Brazil

We performed an association between high-grade squamous intraepithelial lesions (HSIL), low-grade squamous intraepithelial lesions (LSIL) and single or multiple vaccine-target as well as non-vaccine target Human papillomavirus (HPV) types. Using bead-based HPV genotyping, 594 gynecological samples were genotyped. An association between squamous intraepithelial lesion (SIL) and presence of HPV16, 18, 31, 58 and 56 types were calculated. The risk was estimated by using odds ratio (OR) and 95% of confidence intervals (CI). A total of 370 (62.3%) women were HPV positive. Among these, 157 (42.7%) presented a single HPV infection, and 212 (57.3%) were infected by more than one HPV type. HPV31 was the most prevalent genotype, regardless single and multiple HPV infections. Single infection with HPV31 was associated with LSIL (OR=2.32; 95%CI: 1.01 to 5.32; p=0.04); HPV31 was also associated with LSIL (OR=3.28; 95%CI: 1.74 to 6.19; p= 0.0002) and HSIL (OR=3.82; 95%CI: 2.10 to 6.97; p<0.001) in multiple HPV infections. Risk to harbor cervical lesions was observed in multiple HPV infections with regard to the HPV56 (OR=5.39; 95%CI: 2.44 to 11.90; p<0.001for LSIL; OR=5.37; 95%CI: 2.71 to 10.69; p<0.001) and HPV58 (OR=3.29; 95%CI: 1.34 to 8.09; p=0.0091 for LSIL; OR=3.55; 95%CI: 1.56 to 8.11; p=0.0026) genotypes. In addition, women coinfected with HPV16/31/56 types had 6 and 5-fold increased risk of HSIL (OR=6.46; 95%CI: 1.89 to 22.09; p=0.002) and LSIL (OR=5.22; 95%CI: 1.10 to 24.70; p=0.03), respectively. Multiple HPV infections without HPV16/18 has 2-fold increased risk of HSIL (OR=2.57; 95%CI: 1.41 to 4.70; p=0.002) and LSIL OR=2.03; 95%CI: 1.08 to 3.79; p=0.02). The results of this study suggest that single and multiple vaccine target as well as non-vaccine target HPV types are associated with LSIL and HSIL. These finding should be taken into consideration in the design of HPV vaccination strategies.

How to best measure the effectiveness of male human papillomavirus vaccine programmes?

In many countries now, vaccination of young adolescent girls with prophylactic human papillomavirus (HPV) vaccines has been rolled out as a public health programme. In countries where coverage has been high, this has led to dramatic reductions in cervical high-grade precancerous lesions, as well as genital warts. A reduction in circulating vaccine-related HPV types has also been demonstrated. With the introduction of gender-neutral approaches incorporating universal vaccination of pre-adolescent boys in some countries, implementation of post-vaccine monitoring will be critical to evaluate the incremental impact of male vaccination. In contrast to cervical screening programmes, population-wide screening for HPV infection or related disease in males is not recommended; hence real-time monitoring of HPV vaccine effectiveness in males will require dedicated surveillance strategies. Monitoring the prevalence of circulating genital HPV types using a sentinel surveillance model could offer a good surrogate marker of early vaccine effectiveness in males. However, such an approach requires careful consideration of the most appropriate anatomical sites from which to collect specimens, the best sampling methods and the most sensitive assays to use. Additionally, in assessing an accurate measure of the impact of HPV vaccination in the male population, the effect of herd protection will need to be assessed, as most male programmes will commence in the setting of established female programmes. This poses an interesting epidemiological challenge.

High prevalence of hpv multiple genotypes in women with persistent chlamydia trachomatis infection

BACKGROUND

Chlamydia trachomatis interaction with HR-HPV types has highlighted a central role in cervical cancer development. The aim of this study was to investigate HPV prevalence and genotypes distribution in women at risk for C. trachomatis infection and negative for intraepithelial lesion or malignancy.

METHODS

1071 cervical swabs were tested for C. trachomatis by Real Time PCR and genotyping by ompA gene sequencing. Additionally, a quantitative Real time-PCR was performed to assess the expression of the C. trachomatis Hsp60-encoding gene (Ct604 portion), linked to a persistent status of infection. HPV infection and genotypes was investigated in C. trachomatis positive women using Luminex technology.

RESULTS

C. trachomatis infection was detected in 53 out of 1071 (4.5%) samples, of which the 53% resulted positive for Hsp60 gene expression. The overall prevalence of HPV infection in C. trachomatis positive samples was of 60.4% (32/53): in 37.5% of samples was present a single genotype, while multiple genotypes infections were found in the 62.5% of them. Among women with a C. trachomatis chronic infection, 68% were HPV co-infected and the 79% showed multiple genotypes. Should be noted that levels of C. trachomatis Hsp60 expression in HPV co-infected women were significantly lower compared to women infected only with C. trachomatis. The C. trachomatis serotype F was found in the majority of samples, independently of HPV infection.

CONCLUSIONS

A high prevalence of HPV multiple infections have been found in young women affected with a C. trachomatis chronic infection. These observations suggested that the expression of CHSP60-1, interfering with both apoptotic and cellular senescence pathways, may promote a favourable local microenvironment for HPV infection.

HPV and Chlamydia trachomatis co-detection in young asymptomatic women from high incidence area for cervical cancer

Chlamydia trachomatis causing chronic inflammatory diseases has investigated as possible human papillomavirus (HPV) cofactor in cervical cancer. The aim of this study is to evaluate the prevalence of Chlamydia trachomatis and HPV co-infection in different cohorts of asymptomatic women from a Northern Italy area at high incidence for cervical cancer. Cervical samples from 441 females were collected from Cervical Cancer Screening Program, Sexually Transmitted Infectious and Assisted Reproductive Technology centres. HPV and Chlamydia trachomatis were detected simultaneously and genotyped using a highly sensitive bead based assay. The overall prevalence of Chlamydia trachomatis was estimated 9.7%, in contrast with the reported national data of 2.3%, and co-infection with HPV was diagnosed in the 17% of the samples. In females ≤ 25 years of age, the infection reached a peak of 22% and co-infection with HPV of 45.8% (P < 0.001). Of note, in young females diagnosed with low grade cervical lesions, no significant difference between Chlamydia trachomatis and HPV distribution was observed, while differently, HPV co-infection was found significantly associated to the presence of intraepithelial lesions when compared to older females (20% vs. 1%; P < 0.001). In this study, the use of a high sensitive molecular technique exhibited higher analytical sensitivity than the referred assays for the diagnosis of Chlamydia trachomatis and HPV co-infection in asymptomatic females, leading to reduction of the potential to identify incorrectly the infection status. An active screening for timely treatment of Chlamydia trachomatis infection is suggested in young females to evaluate a possible decrease in incidence of pre-cancer intraepithelial lesions.

Clinical prediction based on HPV DNA testing by hybrid capture 2 (HC2) in combination with liquid-based cytology (LBC)

Primary screening by HPV DNA testing is an effective method for reducing cervical cancer and has proven more sensitive than cytology. To advance this approach, many molecular methods have been developed. Hybrid capture 2 provides semi-quantitative results in ratios of relative light units and positive cutoff values (RLU/ PC). Twenty-five thousand and five patients were included in this study to analyze the correlation between the ratio of RLU/PC and stage of cervical dysplasia. The results show that the RLU/PC ratios ranged from 0-3500 while almost normal cases, ASC-US and ASC-H, had values below 200. Of those samples negative for cytology markers, 94.6% were normal and their RLU/PC ratios were less than 4. With an RLU/PC ratio greater than 4 and less than or equal to 300, the percentages in all age groups were normal 53.6%, LSIL 20.2%, ASC-US 17.2%, HSIL 6.13%, ASC-H 2.72%, and AGC 0.11%, respectively. In contrast, 64.0% of samples with a RLU/ PC ratio greater than 300 and less than or equal to 3500 were LSIL. These results should contribute to cost effective cervical cancer management strategies. Further studies of associations with particular HPV genotypes would be useful to predict the risk of progression to cancer.

Comprehensive analysis of HPV expression in laryngeal squamous cell carcinoma

Role of human papillomavirus (HPV) in laryngeal carcinoma remains controversial. The aim of this study is to evaluate the role of HPV in laryngeal squamous cell carcinoma by determining presence of markers of viral infection. HPV DNA and E6*I mRNA status was determined by type-specific E7 PCR bead-based multiplex genotyping and RT-PCR assays in laryngeal squamous cell carcinoma biopsy samples. p16(INK4a) and COX-2 expression was determined by immunohistochemistry. Four cases out of 32 (13%) were HPV DNA+: HPV 11 (n = 1), HPV 31 (n = 3), HPV 59 (n = 1). One double infection: HPV 11 and HPV 31. p16(INK4a) was overexpressed in three cases (9%) and COX-2 in 17 cases (53%). Two of four HPV DNA+ samples had E6*I mRNA for HPV 31 and overexpressed p16(INK4a) and COX-2. HPV appears to play an active role in a small subset of laryngeal squamous cell carcinoma. p16(INK4a) can be used as a surrogate marker of transcriptionally active HPV infection; COX-2 expression had no correlation with HPV DNA and/or RNA positivity.

Human Papillomavirus prevalence and probable first effects of vaccination in 20 to 25 year-old women in Germany: a population-based cross-sectional study via home-based self-sampling

Background

Estimates of Human Papillomavirus (HPV) prevalence in a population prior to and after HPV vaccine introduction are essential to evaluate the short-term impact of vaccination.

Methods

Between 2010 and 2012 we conducted a population-based cross-sectional study in Germany to determine HPV prevalence, genotype distribution and risk factors for HPV-infection in women aged 20-25 years. Women were recruited by a two-step cluster sampling approach. A home-based self-collection of cervicovaginal lavages was used. Specimens were analysed using a general primer GP5+/GP6+-based polymerase chain reaction and genotyped for 18 high-risk and 6 low-risk HPV- strains by Luminex-based multiplexed genotyping.

Results

Among 787 included women, 512 were not vaccinated against HPV. In the non-vaccinated population, HPV prevalence of any type was 38.1%, with HPV 16 (19.5%) being the most prevalent genotype. Prevalence of any high-risk type was 34.4%, and in 17.4% of all women, more than one genotype was identified. A higher number of lifetime sexual partners and low educational status were independently associated with HPV-infection. In 223 vaccinated women, prevalence of HPV 16/18 was significantly lower compared to non-vaccinated women (13.9% vs. 22.5%, p = 0.007). When stratifying by age groups, this difference was only significant in women aged 20-21 years, who at time of vaccination were on average younger and had less previous sexual contacts than women aged 22-25 years.

Conclusion

We demonstrate a high prevalence of high-risk HPV genotypes in non-vaccinated women living in Germany that can be potentially prevented by vaccination. Probable first vaccination effects on the HPV prevalence were observed in women who were vaccinated at younger age. This finding reinforces the recommendation to vaccinate girls in early adolescence.

Beta defensin-1 gene polymorphisms and susceptibility to atypical squamous cells of undetermined significance lesions in Italian gynecological patients

The role of the human beta-defensin 1 (hBD-1) in the susceptibility to the onset of the Atypical Squamous Cells of Undetermined Significance (ASCUS) lesion, in the presence or not of HPV infection, is still unknown. In the current study, the three functional single nucleotide polymorphisms (SNPs) -52G > A, -44C > G, and -20G > A at the 5' un-translated region (UTR) of DEFB1 gene, encoding hBD-1, were analyzed in ASCUS lesion gynecological patients and healthy women from the north-east of Italy (Trieste). Cervical samples from 249 European-Caucasian women were collected, screened for HPV and cytologically evaluated; DEFB1 genotyping has been performed by direct sequencing. No significant differences were found for -52G > A, -44C > G, and -20G > A SNPs allele and genotype frequencies between women with and without ASCUS lesions. DEFB1 minor haplotypes were significantly more frequent in ASCUS lesion positive than negative women, associating with an increased risk of this type of lesion. When women were stratified according to HPV infection status, significant differences in the distribution of -52G > A SNP genotype frequencies were found: the presence of the A allele in the homozygous genotype A/A associated with a lower risk of developing ASCUS lesions in HPV negative women. DEFB1 minor haplotypes were also associated with an increased risk of developing ASCUS lesions, being significantly more frequent in HPV negative women with lesions, than without lesions. Although these results highlight the possible involvement of DEFB1, further studies are needed to support the role of DEFB1 in the modulation of the susceptibility to ASCUS lesions.

Human papillomavirus infection in women in four regions of Senegal

Cervical cancer is the most frequent cancer among women in Senegal. However, there are few data concerning the human papillomavirus (HPV) types inducing neoplasia and cervical cancers and their prevalence in the general population of Senegal. The aim of this study is to determine the prevalence of HPV infection in Senegalese women aged 18 years and older in Dakar Region and three other regions. Cervical samples were collected from 498 women aged 18-80 years (mean, 42.1 years) in Dakar Region. Also, 438 samples were collected from three other regions: Thiès, Saint-Louis, and Louga. The samples were screened for 21 HPV genotypes using an HPV type-specific E7 PCR bead-based multiplex genotyping assay (TS-MPG). The prevalence of high risk (HR)-HPV in Dakar Region was 17.4%. HPV 52 (3.2%) was the most prevalent HPV type, followed by HPV 31 (3.0%) and HPV 16, 45, and 53 (all 2.8%). In the Thiès, Saint-Louis, and Louga Regions, the prevalence of HR-HPV was 23.2%, 13.1%, and 19.4%, respectively. The study revealed the specificity of HPV prevalence in Dakar Region and other regions of Senegal. The observed patterns show some differences compared with other regions of the world. These findings raise the possibility that, in addition to HPV 16 and HPV 18, other HPV types should be considered for a vaccination program in Senegal. However, additional studies to determine the HPV type distribution in cervical cancer specimens in Senegal are required to further corroborate this hypothesis.

Risk factors for cervical human papillomavirus infection and high-grade intraepithelial lesion in women aged 20 to 31 years in Germany

BACKGROUND

Persistent infection with high-risk human papillomaviruses (HPVs) can lead to cervical intraepithelial lesion and cervical cancer. Sexual behavior and smoking have been identified as risk factors for HPV infection. However, it is unclear which factors account for the persistence of HPV infection and for high-grade squamous intraepithelial lesions (HSIL). Therefore, we conducted a study to identify epidemiological risk factors for the following: (1) the presence of HPV among women without a recent diagnosis of HSIL and (2) HSIL.

MATERIALS AND METHODS

Participants aged 20 to 31 years were recruited at 2 study sites. All women received a cervical Papanicolaou test, were tested for HPV, and categorized into 1 of 3 different groups: The women of the first group had negative cytological test results and a negative HPV test result (HPV-negative group), and the women of the second group had negative cytological test result but positive HPV test result (HPV-positive group). The third group consisted of women with a diagnosis of HSIL (HSIL group). We first compared the HPV-negative group with the HPV-positive group, and then the HPV-positive group with the HSIL group.

RESULTS

One hundred forty-seven women were included: 53 women in the HPV-negative group, 46 women in the HPV-positive group, and 48 women in the HSIL group. Comparing the HPV-negative with the HPV-positive group, we found that more than 5 sexual partners during a lifetime were independently associated with cervical HPV infection, whereas the chance of being infected decreased with older age. Irregular condom use during one-night stands or smoking was associated with HPV infection only in univariable but not multivariable analysis. In contrast, older age and having had genital warts were independently associated with an HSIL diagnosis when comparing the HPV-positive group with the HSIL group.

DISCUSSION

Although the study was hampered by its relatively small sample size, our data suggest that main risk factors for the acquisition of HPV infection are a higher number of sexual partners and younger age, whereas older age and genital warts may be epidemiological cofactors in the development of HSIL.