A comparison of early (E7) and late (L1) primer-mediated amplification of papillomaviral DNA in cervical neoplasia

Updates in the cause of sinonasal inverted papilloma and malignant transformation to squamous cell carcinoma

PURPOSE OF REVIEW

The purpose of this study was to give an overview of recently published articles investigating the cause of inverted papilloma and possible mechanisms mediating malignant transformation into squamous cell carcinoma (SCCa).

RECENT FINDINGS

Inverted papilloma is a sinonasal tumour that is benign in nature, but has a tendency for local invasion, recurrence and malignant degeneration. Its pathogenesis has not been elucidated and the etiological role for human papillomavirus virus (HPV) has been controversial. Recent reports have varied in detection method (mRNA ISH, DNA ISH and PCR amplification of highly conserved regions of the viral genome), ranging from 0 to 100%. Advances in meta-genomics have permitted detection of HPV viral signatures that were previously cost-prohibitive, and there appears to be a potential role for both low-risk and high-risk in the cause of the disease. Activating EGFR mutations have also been identified to be correlated with malignant transformation, which may be exclusive of HPV infection. Furthermore, more comprehensive approaches in detecting genomic markers have been reported, with HOX-related genes and epithelial-mesenchymal-transition-related gene sets appear to be differentially upregulated.

SUMMARY

Sinonasal inverted papilloma is a diverse disease that is predominantly benign, but it harbours the potential for malignant degeneration in the SCCa with cause yet to be elucidated. Current evidence supports a potential role for high-risk HPV in a subset of SCCa, with the role of low-risk HPV yet to be defined. Historic studies of individual and small groups of molecular markers have not consistently adequate characterize signalling pathways underpinning the oncogenesis, and comprehensive genomic studies are needed to better understand the disease.

Comparison of Polymerase Chain Reaction and Immunohistochemistry Assays for Analysing Human Papillomavirus Infection in Oral Squamous Cell Carcinoma

INTRODUCTION

Polymerase Chain Reaction (PCR) and Immunohistochemistry (IHC) are two well-known techniques used for the diagnoses of genetic diseases, tumours and different pathogens. PCR basically amplify regions of DNA within a single molecule which may have etiologic significance, it is a method for in vitro amplification of specific DNA or RNA sequences, whereas IHC is used to verify tissue constituents (the antigens) with the utilization of specific antibodies that can be visualized through staining.

AIM

To compare and analyse PCR and IHC for their sensitivity to detect Human Papillomavirus (HPV) in Oral Squamous Cell Carcinoma (OSCC).

MATERIALS AND METHODS

This study was based on samples retrospectively collected from 47 patients with primary OSCC who were diagnosed and treated at The Aga Khan University Hospital, Karachi, Pakistan, during the period of January 2010 to December 2013. Inclusion criteria were complete clinicopathologic data, adequate clinical follow up and availability of sufficient paraffin- embedded tumour material. HPV general and type specific 16 and 18 were investigated by means of PCR. HPV immunoreactivity was further investigated by means of IHC.

RESULTS

Among the 47 evaluated patients, 32 (68.1%) were male and 15 (31.9%) were female, PCR detected the presence of HPV in 32 (68.1%) patients while IHC showed no positive test results. p53 was positive in 32 (68.1%) patients and negative in 15 (31.9%). HPV type 16 being most prevalent showing positivity in 27 (57.4%) patients whereas, type 18 was positive in only 1 (2.1%) patient.

CONCLUSION

We concluded that PCR is more sensitive and reliable when diagnosing and detecting HPV for OSCC rather than IHC as results from IHC were all negative and insignificant, hence PCR should be the first initial diagnostic test for detecting HPV due to its better sensitivity and successful detection of HPV.

Human papillomavirus and head and neck carcinomas: focus on evidence in the babel of published data

Human papillomavirus (HPV)-associated squamous cell carcinoma of the oropharynx is a well-defined entity mostly affecting young to middle-aged male non-smokers. It is generally associated with a favourable outcome, and for this reason a less intensive therapeutic approach has been proposed for this subset of patients. The incidence of HPV-associated oropharyngeal cancers is rapidly increasing in most Western countries, but detailed epidemiological data are not available for the Italian population. Furthermore, among other head and neck regions, a smaller proportion of oral high-grade dysplasia and cancers seems to depend on HPV infection, whereas its role in laryngeal cancer is recognised as less relevant. HPV-dependent neoplastic transformation depends on the expression of viral oncogenes in the infected host cell that can only be directly documented through viral oncogene mRNA identification. The consensus on how to classify these patients from clinical and laboratory diagnostic points of view is still limited, with different approaches based on one or more diagnostic techniques including p16 immunostaining, in situ hybridisation and polymerase chain reation (PCR) amplification of viral DNA. The possibility of early diagnosis relying on the identification of HPV infection in oral and oropharyngeal exfoliated cells has so far provided unsatisfactory results, although viral persistence after treatment has been associated with risk of recurrence. Presently, sufficient data are not available to document the natural history and progression from tonsillar HPV infection to oropharyngeal cancer development, and to clearly define the modality of transmission and risk exposure, among which sexual behaviours appear to play a relevant role. The diffusion of HPV vaccination and its administration to both genders will undoubtedly dramatically modify the epidemiology of HPV-related head and neck cancers in the coming years.

E1 detection as prognosticator in human papillomavirus-positive head and neck cancers

PURPOSE

HPV-related locally advanced head and neck cancers (LA-HNCs) show a good prognosis. This study aimed to investigate the HPV prevalence in LA-HNCs and compare the prognostic value of E1, E6 and L1 genomic viral fragments and p16, individually and in combination, in order to find the best prognosticator in terms of overall survival (OS) and progression-free survival (PFS).

PATIENTS AND METHODS

HPV16 was searched in 255 LA-HNC formalin-fixed paraffin-embedded tumor tissues, 89 oropharyngeal cancers (OPCs), and 166 non-OPCs by DNA-PCR with 3 primer pairs. p16 was analyzed by immunohistochemistry in 235 patients.

RESULTS

The prevalence of positive samples decreased constantly from E6 to L1 and E1 in both OPCs and non-OPCs. Each LA-HNC patient highlighted variable positivity for each fragment. OPCs showed a higher prevalence of positive samples compared to non-OPCs.Positive coexistence of all the fragments was more common in OPCs (31.5%) than non-OPCs (4.2%), and E1 detection was always associated with E6 and L1. E1-positive OPCs showed improved OS (p = 0.012) and PFS (p = 0.036), while L1- or E6-positive ones did not. p16-positive patients were more prevalent in the OPC (29.8%) than the non-OPC group (7.3%) (p<0.0001) and its prognostic value was not superior to that of E1. However, the multivariate Cox analysis which included E1, L1, E6 status and p16 expression did not show a significant p value.

CONCLUSIONS

Though HPV16 positivity measured by DNA-PCR was higher for L1 and E6, they performed weakly as prognosticators; E1 might become a strong prognostic marker for OS and PFS in OPCs.

Circulation of human papillomavirus (HPV) genotypes in women from Córdoba, Argentina, with squamous intraepithelial lesions

Human papillomavirus (HPV) can induce a wide spectrum of squamous intraepithelial lesions (SIL) of varying severity. The aim of the present study was to establish the frequency of HPV infection and identify the genotypes circulating in women from Córdoba, Argentina, in relation to age and cytology. A total of 186 women, between 18 and 65 years old, with antecedents of SIL, underwent a pelvic examination and had cervical cells collected for cytology and HPV DNA detection. Ninety-six samples (51.6%) were positive for HPV detection, and sixty-three (65.6%) of them showed the presence of at least one HR-HPV. Low- and high-grade SIL showed significant association in patients younger than 35 years of age. We found 18 different genotypes, with a greater presence of HR-HPV. Genotypes 16 and 6 were the most frequent. Seven (7.3%) multiple infections, 85.7% of which had at least one HR-HPV, were detected. The detection of a large number of different HPV genotypes is a warning sign. It is thus necessary to strengthen the monitoring of the circulation of high-risk genotypes, currently less prevalent in intraepithelial lesions, as a control measure for the possible impact of the implementation of vaccines against genotypes 16 and 18.

A discrete population of squamocolumnar junction cells implicated in the pathogenesis of cervical cancer

Infection by carcinogenic human papillomaviruses (HPV) results in precancers [cervical intraepithelial neoplasia (CIN)] and cancers near the ectoendocervical squamocolumnar (SC) junction of the cervix. However, the specific cells targeted by HPV have not been identified and the cellular origin of cervical cancer remains elusive. In this study, we uncovered a discrete population of SC junctional cells with unique morphology and gene-expression profile. We also demonstrated that the selected junctional biomarkers were expressed by a high percentage of high-grade CIN and cervical cancers associated with carcinogenic HPVs but rarely in ectocervical/transformation zone CINs or those associated with noncarcinogenic HPVs. That the original SC junction immunophenotype was not regenerated at new SC junctions following excision, not induced by expression of viral oncoproteins in foreskin keratinocytes, and not seen in HPV-related precursors of the vagina, vulva, and penis further support the notion that junctional cells are the source of cervical cancer. Taken together, our findings suggest that carcinogenic HPV-related CINs and cervical cancers are linked to a small, discrete cell population that localizes to the SC junction of the cervix, expresses a unique gene expression signature, and is not regenerated after excision. The findings in this study uncover a potential target for cervical cancer prevention, provide insight into the risk assessment of cervical lesions, and establish a model for elucidating the pathway to cervical cancer following carcinogenic HPV infection.

Ancillary studies in determining human papillomavirus status of squamous cell carcinoma of the oropharynx: a review

Squamous cell carcinoma (SCC) of the oral cavity and pharynx represents the sixth most common form of malignancy worldwide. A significant proportion of these cases are related to human papillomavirus (HPV) infection. In general, HPV-associated SCC is more commonly nonkeratinizing and poorly differentiated, whereas non-HPV-associated SCC is typically keratinizing and moderately differentiated. Nevertheless, significant overlap in morphology is seen between these two forms of SCC. The purpose of this paper is to highlight the utility of ancillary studies in the establishment of HPV status of oropharyngeal SCC, including p16 immunohistochemistry, high-risk HPV in situ hybridization, polymerase chain reaction, and newer HPV detection modalities.

Distribution patterns of infection with multiple types of human papillomaviruses and their association with risk factors

BACKGROUND

Infection with multiple types of human papillomavirus (HPV) is one of the main risk factors associated with the development of cervical lesions. In this study, cervical samples collected from 1,810 women with diverse sociocultural backgrounds, who attended to their cervical screening program in different geographical regions of Colombia, were examined for the presence of cervical lesions and HPV by Papanicolau testing and DNA PCR detection, respectively.

PRINCIPAL FINDINGS

The negative binomial distribution model used in this study showed differences between the observed and expected values within some risk factor categories analyzed. Particularly in the case of single infection and coinfection with more than 4 HPV types, observed frequencies were smaller than expected, while the number of women infected with 2 to 4 viral types were higher than expected. Data analysis according to a negative binomial regression showed an increase in the risk of acquiring more HPV types in women who were of indigenous ethnicity (+37.8%), while this risk decreased in women who had given birth more than 4 times (-31.1%), or were of mestizo (-24.6%) or black (-40.9%) ethnicity.

CONCLUSIONS

According to a theoretical probability distribution, the observed number of women having either a single infection or more than 4 viral types was smaller than expected, while for those infected with 2-4 HPV types it was larger than expected. Taking into account that this study showed a higher HPV coinfection rate in the indigenous ethnicity, the role of underlying factors should be assessed in detail in future studies.

Polymerase chain reaction detection of HPV in squamous carcinoma of the oropharynx

Human papillomavirus (HPV) testing is routinely performed on oropharyngeal carcinomas. We compared the Access Genetics (Minneapolis, MN) polymerase chain reaction (PCR) assay (AGPCR), DNA-DNA in situ hybridization (ISH; Ventana, Tucson, AZ), and HPV-16 E7 PCR amplification in consecutively accessioned oropharyngeal cancers. We tested 126 cases by both PCR methods; 102 were positive by either for a maximum positive rate (MPR) of 81.0%. Relative to the MPR, the sensitivities of AGPCR and E7 PCR were 90.2% and 72.5%, respectively. Of 17 AGPCR+ cases tested by ISH, 14/14 unequivocally positive/negative were concordant. All cases (97/97) positive by either PCR assay were positive for p16. There was no relationship between level of histologic differentiation and HPV status. ISH and AGPCR have comparable performance for the detection of HPV in oropharyngeal carcinomas. PCR is a suitable and economical assay that is comparable to ISH in sensitivity and may provide logistical advantages relative to ISH for assessing HPV status in oropharyngeal malignancies. However, it is imperative that appropriate sensitivity controls be in place for such assays.

Differentiated vulvar intraepithelial neoplasia contains Tp53 mutations and is genetically linked to vulvar squamous cell carcinoma

Differentiated vulvar intraepithelial neoplasia is a unique precursor to vulvar squamous cell carcinoma that is typically HPV-negative and frequently associated with nuclear p53 staining. These features imply a mode of pathogenesis involving somatic mutations. However, the genetic relationship of differentiated vulvar intraepithelial neoplasm and vulvar squamous cell carcinoma and the role of Tp53 mutations in this process have not been resolved. We analyzed 11 differentiated vulvar intraepithelial neoplasms and 6 associated vulvar squamous cell carcinomas. Sections were stained for p53 and p63 and DNA from multiple epithelial sites, representing normal control tissues (n=10), differentiated vulvar intraepithelial neoplasias (n=18), and vulvar squamous cell carcinomas (n=6), were obtained by laser capture microdissection, and sequenced for exons 2-11 of Tp53. Six of 10 cases contained at least one Tp53 mutation-positive differentiated vulvar intraepithelial neoplasia focus; 4 strongly p53 immuno-positive and 2 negative. Staining for p53 and p63 co-localized, targeting the immature epithelium, but surface epithelium was Tp53 mutation-positive. Four of five vulvar squamous cell carcinomas were Tp53 mutation-positive; two shared identical Tp53 mutation with adjacent differentiated vulvar intraepithelial neoplasia. Disparate foci of differentiated vulvar intraepithelial neoplasia often showed different mutations consistent with multiple neoplastic clones. Differentiated vulvar intraepithelial neoplasia is, with few exceptions, associated with Tp53 mutations and will be p53 immunopositive when missense mutations (versus some nonsense and all deletion mutations) are present. Multiple Tp53 mutations in different sites supports the presence of multiple independent genetic events, but shared Tp53 mutations in both differentiated vulvar intraepithelial neoplasia and vulvar squamous cell carcinoma support a genetic relationship between the two. The confinement of p53 staining to immature cell nuclei is consistent with maturation-dependent degradation of mutant p53 protein.

A novel method of HPV genotyping using Hybrid Capture sample preparation method combined with GP5+/6+ PCR and multiplex detection on Luminex XMAP

A novel DNA detection assay comprising Hybrid Capture sample preparation, GP5+/6+ PCR with modifications and Luminex 100 detection was developed and applied to genotyping of human papillomavirus (HPV) in cervical samples. Target-specific sample preparation was performed using magnetic beads conjugated with Hybrid Capture (HC) antibody. DNA-RNA hybrids were formed between DNA target and RNA probes and captured on HC-beads. DNA on magnetic beads was amplified without elution using consensus GP5+/6+ PCR and then genotyped on Luminex beads using hybridization probes for the 17 high-risk HPV types 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73, 82 and an internal control. This new sequence-specific Hybrid Capture sample preparation is fast, efficient and allows direct HPV genotyping by PCR. Compared to traditional non-sequence-specific sample preparation methods, HC sample preparation demonstrated slightly better detection of multiple HPV infections. The clinical utility of this method was demonstrated on cervical samples positive for HR HPV by the Hybrid Capture 2 (hc2) screening assay.

The role of the human papillomavirus in the pathogenesis of Schneiderian inverted papillomas: an analytic overview of the evidence

BACKGROUND

Evidence of an etiological role for human papillomavirus (HPV) in Schneiderian inverted papillomas IP arose in the late 1980's; yet almost three decades later, the association between HPV and IP has yet to be universally accepted. This is probably due to the disparate HPV detection rates in IP reported in the literature. We analyzed the weight of published data in order to address the following questions: why do the HPV detection rates in IP vary so greatly? What is the relationship between low-risk (LR) and high-risk (HR) HPV types and HPV detection rates in IP? Is there a relationship between the presence and type of HPV in IP and recurrence and malignant progression?

MATERIALS AND METHODS

A search using the Pubmed search engine was performed to identify studies published in English from 01/87 through 12/06 using the MeSH terms ''HPV'' and ''Inverted", "Exophytic", "Oncocytic Schneiderian" or "Fungiform papilloma''. Data was abstracted from publications including histology, HPV target, HPV type, method of detection, etc. HPV results were stratified by histology and other variables. Tests for heterogeneity (between-study variability) were conducted, and weighted prevalence (WP) estimates and 95% confidence intervals (CI) were calculated using a random-effects inverse-variance model stratified on study. The association between HPV IP recurrence was estimated by random-effects inverse-variance weighted odds ratio (OR).

RESULTS

Weighted estimates revealed similar detection rates across detection methods, 26.8% (95%CI 16.4-37.2%) by ISH, 25.2% (95%CI 14.7-35.6%) by consensus PCR, and 23.6% (95%CI 12.2-35.0%) by type-specific PCR. A preponderance of HPV 6/11 is found in IP as compared to HPV 16/18; the overall unadjusted ratio of LR to high-risk HR HPV types is 2.8:1 The HPV detection rates significantly increase (Wald t-test P < 0.02) in IPs with high-grade dysplasia (WP 55.8%, 95%CI 30.5-81.0%) and carcinoma (WP 55.1%, 95%CI 37.0-73.2%) as compared to IPs with no dysplasia or mild dysplasia (WP 22.3%, 95%CI 15.9-28.6%). Furthermore, the preponderance of LR HPV in benign IP (ratio LR/HR = 4.8:1) shifts in dysplastic and malignant IP. The LR/HR ratio is 1.1:1 for IPs with high-grade dysplasias, this ratio is inverted to favor HR HPV (1:2.4) for malignant IP. Recurrences developed in 44 of 236 patients; HPV was detected in 27 of 44 IPs (WP 57.9%, 95%CI 31.6-84.2%) that developed recurrences and in 24 of 192 IPs (WP 9.7%, 95%CI 4.4-15.0%) that did not develop recurrence. The presence of HPV was significantly associated with the likelihood of developing recurrence (weighted OR of 10.2, 95%CI 3.2-32.8).

CONCLUSIONS

We hypothesize that LR HPV may induce IP formation, and then are lost as infected cells are shed, as a "hit and run" phenomenon. HPV detection rates increase in dysplastic IP and SCC-ex-IP with increasing ratio of HR to LR HPV types, compared to nondysplastic IP. We believe that one explanation for the variation in HPV detection rates between different studies may be the actual histologic composition of the cohort. That is, if one series contains a higher frequency of dysplastic and malignant IP, it may have a higher detection rate than another series which contains only nondysplastic IP. We hypothesize that the higher rates of HPV detection in dysplastic and malignant IP may be related to HPV integration. The implication of this is that HPV sub-type testing may identify patients at risk for recurrence, or progression to dysplasia and malignancy, and thus may impact surveillance protocols.

Presence of E6 and E7 mRNA from human papillomavirus types 16, 18, 31, 33, and 45 in the majority of cervical carcinomas

The oncogenic potential of the human papillomavirus (HPV) early genes E6 and E7 is well established and a source of interest with regard to HPV testing for cervical carcinoma. Here we present a study performed with 204 histologically confirmed invasive cervical squamous cell carcinomas (SCCs) in which we evaluated the HPV E6 and E7 mRNA detection assay PreTect HPV-Proofer for detection of high-risk HPV types 16, 18, 31, 33, and 45. For further evaluation, detection of E6 and E7 mRNA from HPV types 35, 52, and 58 by real-time multiplex nucleic acid sequence-based amplification was also included. For comparison and to assess the overall prevalence of various HPV types, samples were also tested for HPV DNA by both consensus and type-specific PCR, reverse line blotting, sequencing, and in situ hybridization. The overall prevalence of HPV was 97%. HPV E6 and E7 transcripts were detected in 188 of 204 (92%) biopsy specimens, of which 181 contained one of the following HPV types: 16, 18, 31, 33, or 45. Consensus PCR and type-specific PCR detected HPV in 187 of 204 and 188 of 204 (92%) specimens, respectively. In conclusion, this study verifies the presence of HPV E6 and E7 mRNA in SCCs and demonstrates that HPV infections among Norwegian women with SCCs are limited mainly to the five high-risk types, 16, 18, 31, 33, and 45. This, together with the fact that PreTect HPV-Proofer detects the HPV oncogenic transcripts, suggests that the assay is a valuable approach in the field of HPV detection in cervical carcinoma.

Enhanced detection and typing of human papillomavirus (HPV) DNA in anogenital samples with PGMY primers and the Linear array HPV genotyping test

The Roche PGMY primer-based research prototype line blot assay (PGMY-LB) is a convenient tool in epidemiological studies for the detection and typing of human papillomavirus (HPV) DNA. This assay has been optimized and is being commercialized as the Linear Array HPV genotyping test (LA-HPV). We assessed the agreement between LA-HPV and PGMY-LB for detection and typing of 37 HPV genotypes in 528 anogenital samples (236 anal, 146 physician-collected cervical, and 146 self-collected cervicovaginal swabs) obtained from human immunodeficiency virus-seropositive individuals (236 men and 146 women). HPV DNA was detected in 433 (82.0%) and 458 (86.7%) samples with PGMY-LB and LA-HPV (P = 0.047), respectively, for an excellent agreement of 93.8% (kappa = 0.76). Of the 17,094 HPV typing results, 16,562 (1,743 positive and 14,819 negative results) were concordant between tests (agreement = 96.9%; kappa = 0.76). The mean agreement between tests for each type was 96.4% +/- 2.4% (95% confidence interval [CI], 95.6% to 97.2%; range, 86% to 100%), for an excellent mean kappa value of 0.85 +/- 0.10 (95% CI, 0.82 to 0.87). However, detection rates for most HPV types were greater with LA-HPV. The mean number of types per sample detected by LA-HPV (4.2 +/- 3.4; 95% CI, 3.9 to 4.5; median, 3.0) was greater than that for PGMY-LB (3.4 +/- 3.0; 95% CI, 3.1 to 3.6; median, 2.0) (P < 0.001). The number of types detected in excess by LA-HPV in anal samples correlated with the number of types per sample (r = 0.49 +/- 0.06; P = 0.001) but not with patient age (r = 0.03 +/- 0.06; P = 0.57), CD4 cell counts (r = 0.06 +/- 0.06; P = 0.13), or the grade of anal disease (r = -0.11 +/- 0.06; P = 0.07). LA-HPV compared favorably with PGMY-LB but yielded higher detection rates for newer and well-known HPV types.

The borderline or weakly positive Hybrid Capture II HPV test: a statistical and comparative (PCR) analysis

OBJECTIVES

Recent studies have hypothesized that laboratory contamination may influence interpretation of Hybrid Capture II (HCII) human papillomavirus (HPV) detection assay values.

STUDY DESIGN

To test this hypothesis, 572 consecutive HCII samples were statistically evaluated to test the null hypothesis that cross-well contamination was not present. In addition, 874 consecutive paired samples from patients followed by both HCII and polymerase chain reaction (PCR) analysis were compared.

RESULTS

A Kendall's tau measure of association among adjacent wells yielded a P value of .016, rejecting the null hypothesis of no contamination. Analysis of relative light unit values between 0.8 and 1.5 rejected the null hypothesis at P=.077. Moreover, PCR positivity was significantly higher for samples with HCII values above 1.5 vs 0.8 to 1.5 (P=.001).

CONCLUSION

Cross-well contamination of samples occurs during processing, and may influence interpretation of some borderline positives. The proportion of cases at risk is low (<3%). Nevertheless, this information may be germane to the interpretation and reporting of marginally positive HCII test values.

ZYC101a for treatment of high-grade cervical intraepithelial neoplasia: a randomized controlled trial

OBJECTIVE

The objective of this study was to assess the safety and efficacy of a novel therapeutic, ZYC101a, for the treatment of women with histologically confirmed cervical intraepithelial neoplasia (CIN) 2/3. ZYC101a contains plasmid-DNA-encoding fragments derived from the E6 and E7 proteins of human papillomavirus (HPV) 16 and 18, and is formulated within small biodegradable microparticles.

METHODS

A multicenter, double-blind, randomized, placebo-controlled trial was conducted in a group of women with biopsy-confirmed CIN 2/3. Subjects were randomized to 3 intramuscular doses of either placebo or ZYC101a (100 or 200 microg). Six months after the first injection, subjects underwent cervical conization. The primary endpoint for this study was histologically confirmed resolution of CIN 2/3. A total of 161 subjects were randomized, dosed, and evaluated for safety. After central pathology review, 127 subjects were evaluable for efficacy.

RESULTS

The most common adverse events were related to the injection site, were mild to moderate, and did not worsen at later treatments. The proportion of subjects who resolved was higher in the ZYC101a groups compared to placebo (43% versus 27%), but the difference was not statistically significant (P =.12). In a prospectively defined population of women younger than 25 years (n = 43), resolution was significantly higher in the combined ZYC101a groups compared to placebo (70% versus 23%; P =.007). ZYC101a activity was not restricted to HPV-16-or HPV-18-positive lesions.

CONCLUSIONS

ZYC101a was shown to be well tolerated in all patients and to promote the resolution of CIN 2/3 in women younger than 25 years.

LEVEL OF EVIDENCE

I

The significance of the Papanicolaou smear diagnosis of low-grade squamous intraepithelial lesion cannot exclude high-grade squamous intraepithelial lesion

BACKGROUND

Cervical cytologic specimens that show a low-grade squamous intraepithelial lesion (LSIL) occasionally contain a few cells that are suspicious for, but not diagnostic of, a high-grade squamous intraepithelial lesion (HSIL). In such cases, a diagnosis of LSIL cannot exclude HSIL is rendered. The objective of the current study was to assess the positive predictive value (PPV) for HSIL in follow-up cervical biopsies for these cases.

METHODS

One hundred forty-four women with a Papanicolaou (Pap) diagnosis of LSIL cannot exclude HSIL and their follow-up cervical biopsies were reviewed. Results were compared with a control group of 155 women with a Pap diagnosis of LSIL. A subset of biopsies was tested and typed for human papillomavirus (HPV) DNA by polymerase chain reaction amplification using consensus primers followed by restriction fragment length polymorphism analysis. HPVs were scored as low-risk or high-risk types.

RESULTS

Women with LSIL cannot exclude HSIL had a higher incidence of HSIL (PPV = 29%) on follow-up cervical biopsy than the control group (PPV = 15%, P < 0.01). In addition, SIL, indeterminate grade was diagnosed in 10% of cervical biopsies in the study group as compared with 4% in controls. Review of Pap smears from the study group showed that there were 3 types of cells suspicious for a high-grade lesion: atypical squamous metaplastic cells (62%), atypical keratinized cells (20%), and dysplastic cells of borderline nuclear-to-cytoplasm ratio (18%). HPV analysis confirmed the presence of high-risk HPV types in the study cases with high-grade cervical biopsies.

CONCLUSIONS

Women with a Pap diagnosis of LSIL cannot exclude HSIL appear to be more likely to harbor a high-grade lesion than those diagnosed with LSIL alone. Its use appears warranted. Women with this diagnosis merit appropriate clinical follow-up to exclude HSIL.

HPV16 and HPV18 in genital tumors: Significantly different levels of viral integration and correlation to tumor invasiveness

The integration of the high-risk HPV16 and HPV18 types into the cell genome is considered an important step in malignant transformation. The relationship between the physical status of the virus and clinical/pathological parameters was studied by type-specific and multiplex PCR for E6, E2, and E1 sequences in 86 genital tumors from different sites, consisting of 69 invasive carcinomas (including 5 microinvasive carcinomas), 9 carcinomas in situ, 6 severe dysplasias, and 2 moderate dysplasias. Forty tumors contained HPV16 (46.6%), 7 HPV18 (8.1%), and 39 both viruses (45.3%). HPV16 DNA was found either as pure integrant (35.4%), or pure episome (36.7%), or a mixture of both (27.8%). Conversely, all 46 lesions containing HPV18 showed pure integrated forms. The physical status of both types was not related to the tumor site, the tumor/node/metastasis stage, or the histological differentiation grade of the invasive carcinomas. HPV16 integration was significantly associated with invasiveness. Interestingly, in double infections when HPV16 coexisted with HPV18, its genome was found more frequently in episomal form than in single infections where, conversely, it was mostly integrated (P < 0.0001), suggesting a sort of competition for cell integration sites. The complete HPV18 integration, even in pre-neoplastic lesions, indicates a different behavior in genital transformation compared with HPV16 and may reflect a major aggressiveness of this viral type. In conclusion, virus typing in conjunction with the evaluation of the integration status may provide a better prognostic evaluation together with an improved diagnosis.

Use of PGMY primers in L1 consensus PCR improves detection of human papillomavirus DNA in genital samples

The novel PGMY L1 consensus primer pair is more sensitive than the MY09 and MY11 primer mix for detection and typing with PCR of human papillomavirus (HPV) DNA in genital specimens. We assessed the diagnostic yield of PGMY primers for the detection and typing of HPV by comparing the results obtained with PGMY09/PGMY11 and MY09/MY11/HMB01 on 299 genital samples. Amplicons generated with PGMY primers were typed with the line blot assay (PGMY-line blot), while HPV amplicons obtained with the degenerate primer pool MY09/MY11/HMB01 were detected with type-specific radiolabeled probes in a dot blot assay (standard consensus PCR test). Cervicovaginal lavage samples (N = 272) and cervical scrape samples (N = 27) were tested in parallel with both PCR tests. The PGMY-line blot test detected the presence of HPV DNA more frequently than the standard consensus PCR assay. The concordance for HPV typing between the two assays was 84.3% (214 of 255 samples), for a good kappa value of 0.69. Of the 177 samples containing HPV DNA by at least one method, 40 samples contained at least one HPV type detected only with PGMY-line blot, whereas positivity exclusively with the standard consensus PCR test was found for only 7 samples (P < 0.001). HPV types 45 and 52 were especially more frequently detected with PGMY than MY primers. However, most HPV types were better amplified with PGMY primers, including HPV-16. Samples with discordant results between the two PCR assays more frequently contained multiple HPV types. Studies using PGMY instead of MY primers have the potential to report higher detection rates of HPV infection not only for newer HPV types but also for well-known genital types.

Allelic imbalance in lichen sclerosus, hyperplasia, and intraepithelial neoplasia of the vulva

BACKGROUND

Few studies have addressed in detail the genetic alterations that occur in vulvar squamous carcinomas (VSCC) and their precursor lesions. In a previous study, we determined the most common chromosomal loci for allelic imbalance (AI) in HPV-positive and -negative VSCCs. The present study was designed to determine whether AI and the microsatellite instability phenotype (MIN) were present in epithelial lesions known to be associated with VSCC.

DESIGN

Fifty-seven epithelial loci were analyzed, including HPV-positive (classic) and -negative (differentiated) vulvar intraepithelial neoplasms (VINs), lichen sclerosus (LS), and nonatypical hyperplasias. Thirty-one epithelial loci (55%) were obtained from patients with associated invasive vulvar carcinoma. HPV status was determined by polymerase chain reaction analysis. AI and MIN were determined by comparisons of microdissected target tissues with stromal controls, targeting 11 chromosomal loci.

RESULTS

AI was identified in all epithelial categories, involving at least one chromosomal locus in 67, 53, 50, and 43% of classic VIN, differentiated VIN, hyperplasia, and LS. MIN was infrequent (10-13%), but confined to HPV-negative epithelial changes. HPV-positive lesions generally scored for AI more frequently, but certain loci scored nearly equally in both HPV-positive and -negative lesions, including 8p, 11q, and 17p. There were no differences in frequency of AI between epithelia with and without associated invasive carcinoma.

CONCLUSIONS

The presence of allelic imbalance in vulvar hyperplasia and LS supports the hypothesis that these alterations are at greater risk for neoplasia despite the absence of conspicuous cellular atypia. A model is proposed in which these changes represent monoclonal expansion and are at empirically greater risk for subsequent "critical events" leading to morphologic atypia (VIN). The possibility that these early genetic changes influence both HPV-positive and -negative pathways merits further study.

Low prevalence of human papillomavirus infection in esophageal squamous cell carcinomas from North America: analysis by a highly sensitive and specific polymerase chain reaction-based approach

Several studies have documented the frequent occurrence of human papillomavirus (HPV) DNA in esophageal squamous cell carcinomas (ESCC) in patients from geographic regions where the incidence of this type of cancer is high, such as parts of China. However, the prevalence of HPV infection in ESCC in patients from low incidence geographic regions, such as North America, remains controversial. Therefore, this study evaluates the prevalence of HPV in ESCC in patients from North America, a region where the population is considered at low risk for the development of this neoplasm. ESCCs in 51 patients from three North American cities were analyzed for the presence of HPV DNA by a highly sensitive and specific polymerase chain reaction (PCR) method. Tumor DNA was extracted from formalin-fixed, paraffin-embedded tissue specimens and assayed by PCR using an L1 HPV consensus sequence primer, as well as HPV 16 and HPV 18 E7 region primers. The use of consensus primers to the L1 region allows for detection of most known HPV types and many novel HPV types. Appropriately sized reaction products were analyzed by restriction fragment length polymorphism (RFLP) to confirm the presence and type of HPV, and to exclude products produced by amplification of human DNA sequences. After complete analysis, only one case (2%) of ESCC was HPV DNA positive. This case was independently confirmed using L1 and E7 consensus primers as HPV type 16 and was the only case that tested positive with either assay. These results show that, in contrast to geographic regions where ESCC is prevalent, HPV infection occurs infrequently in association with ESCC in patients from North America.