Detection of human papillomavirus in laryngeal squamous dysplasia and carcinoma. An in situ hybridization and signal amplification study

Nonkeratinizing Squamous Cell Carcinoma In Situ of the Upper Aerodigestive Tract: An HPV-Related Entity

The clinical and pathologic characteristics of human papillomavirus (HPV)-related premalignant lesions in the upper aerodigestive tract have not been adequately studied. There are a few reports of oral cavity HPV-related severe dysplasia with unique morphology (prominent apoptosis/karyorrhexis imparting a 'bowenoid' appearance) and a single case report of HPV-related squamous cell carcinoma in situ with nonkeratinizing histology distinct from the 'bowenoid' pattern that extensively involved the upper aerodigestive tract. The aim of this study was to characterize the morphologic and clinical features of HPV-related severe dysplasia/carcinoma in situ. All cases of upper aerodigestive tract severe dysplasia/carcinoma in situ (111 cases from 98 patients) at Washington University from July 2012 to March 2015 were categorized into histologic types: keratinizing, nonkeratinizing, mixed or 'bowenoid'. There were 83 (85 %) patients with keratinizing, 3 (3 %) nonkeratinizing and 12 (12 %) mixed patterns. The previously reported 'bowenoid' morphology was not identified. All 3 (100 %) nonkeratinizing and 6 (50 %) mixed cases were p16 and HPV RNA in situ hybridization (RNA ISH) positive (100 % concordance between p16 and RNA ISH). Only 2 of 73 keratinizing cases were p16 positive, 1 of which was also HPV RNA ISH positive (1.4 % of keratinizing cases HPV-related). Thus, nonkeratinizing morphology was a strong predictor of transcriptionally-active HPV in severe dysplasia/carcinoma in situ. HPV-related cases most commonly occurred in the floor of mouth and were frequently extensive (≥4 cm) or unresectable.

Laryngeal Squamous Intraepithelial Lesions: An Updated Review on Etiology, Classification, Molecular Changes, and Treatment

Laryngeal carcinogenesis is a multistep process, characterized by an accumulation of genetic changes associated with architectural and cytologic alterations, ranging from squamous hyperplasia to carcinoma in situ and encompassed by the terminology of squamous intraepithelial lesions (SILs). The etiology, classification, genetic changes, and malignant progression of these lesions are reviewed. Tobacco remains the principal etiological factor with gastroesophageal reflux disease recently considered as a possible factor. In contrast, there is little evidence that microbiological agents, especially human papillomavirus infection, are frequently involved in laryngeal carcinogenesis and probably <10% of SILs are driven by biologically active human papillomavirus infection. Light microscopy, despite a degree of subjectivity, remains the mainstay of accurate diagnosis, prognosis, and guidance for a patient's treatment. The currently used classifications, the dysplasia system, squamous intraepithelial neoplasia, and the Ljubljana classification, reflect different standpoints on this important topic. The modified Ljubljana classification, with good interobserver agreement, could be considered as a proposal for a unified classification of laryngeal SILs. This review also briefly discusses recently discovered genetic changes, such as CDKN2A and CTNNB1 genes, and chromosome instability of chromosomes 1 and 7; however, none of these can at present improve histologic diagnosis. Malignant progression of precursor lesions varies from 2% to 74%, according to different studies. Cold-steel microinstruments, CO2 laser, and radiotherapy are used to treat the different grades of precursor lesions. There is as yet no worldwide agreement on the treatment of high-grade lesions and carcinoma in situ.

Role of Human Papillomavirus in the Pathogenesis of Laryngeal Dysplasia

Objective

A synergistic effect between smoking and alcohol intake is the major cause of premalignant and malignant lesions of the larynx, but the risk factors and pathogenesis of the neoplastic transformation in nonsmokers remain poorly defined. The aim of this retrospective study is to establish the relationship between smoking habits and human papillomavirus (HPV) infection in laryngeal dysplasia.

Study Design

Cross-sectional study.

Setting

Academic university hospital.

Subjects and Methods

HPV DNA was amplified from 30 paraffin-embedded laryngeal dysplasia tissue specimens by the polymerase chain reaction using 2 groups of different consensus primers (MYO9/MY11 and LCRF1-4, E7R1-4). Fifteen samples were taken from smokers and 15 from nonsmokers.

Results

The present investigation failed to demonstrate the HPV genome in all samples of laryngeal precancerous lesions, whereas HPV was detected in 4 laryngeal papilloma samples used as control to confirm the reliability of our method on paraffin-embedded samples.

Conclusions

Although the small number of cases in our series limits the power of our statistical analysis, the absence of viral genomes in the specimens analyzed in this study suggests the lack of a relationship between HPV infection and laryngeal dysplasia in smokers as well as in nonsmokers.

Extensive HPV-related carcinoma in situ of the upper aerodigestive tract with 'nonkeratinizing' histologic features

Over the past several decades, it has become clear that human papillomavirus (HPV) is important for the development and progression of many head and neck squamous cell carcinomas, particularly those arising in the oropharyngeal tonsillar crypts. Yet, our understanding of HPV's role in premalignant squamous lesions remains relatively poor. This is in part because premalignant lesions of the oropharyngeal tonsillar crypt tissue, where most HPV-related carcinomas arise, are difficult if not impossible to identify. Recent evidence does suggest a role for HPV in a subset of premalignant lesions of the surface epithelium, especially the oral cavity, despite the rarity of HPV-related invasive squamous cell carcinomas at this site. Furthermore, these HPV-related oral cavity dysplasias appear to have unique, bowenoid histologic features described as 'basaloid' with full-thickness loss of squamous maturation, mitotic figures and apoptosis throughout. Here, we present a unique case of an HPV-related premalignant lesion (squamous cell carcinoma in situ) extensively involving the surface epithelium of the oral cavity, oropharynx and larynx that had 'nonkeratinizing' histologic features typical of HPV-related invasive squamous cell carcinoma. This case was strongly p16 positive by immunohistochemistry and harbored transcriptionally active HPV as demonstrated by E6/E7 RNA in situ hybridization. Furthermore, the patient had an excellent response to radiation treatment.

P16(INK4A) immunostaining is a strong indicator for high-risk-HPV-associated oropharyngeal carcinomas and dysplasias, but is unreliable to predict low-risk-HPV-infection in head and neck papillomas and laryngeal dysplasias

Human papillomavirus (HPV) is a risk factor for the development of benign and malignant mucosal head and neck lesions. P16(INK4A) is often used as a surrogate marker for HPV-infection, although there is still controversy with respect its reliability. Our aim was to determine if p16(INK4A) overexpression can accurately predict both high-risk and low-risk-HPV-presence in (pre)malignant and benign head and neck lesions. P16(INK4A) immunohistochemistry was performed on paraffin-embedded tissue sections of 162 oropharyngeal squamous cell carcinomas (OPSCC), 14 tonsillar and 23 laryngeal dysplasias, and 20 tonsillar and 27 laryngeal papillomas. PCR, enzyme-immunoassay and FISH analysis were used to assess HPV-presence and type. Of the 162 OPSCC and 14 tonsillar dysplasias, 51 (31%) and 10 (71%) were HPV16-positive, respectively. All tonsillar papillomas were HPV-negative and four laryngeal dysplasias and 26 laryngeal papillomas were positive for HPV6 or -11. P16(INK4A) immunohistochemistry revealed a strong nuclear and cytoplasmic staining in 50 out of 51 HPV16-positive and 5 out of 111 HPV-negative OPSCC (p < 0.0001) and in all HPV16-positive tonsillar dysplasias, whereas highly variable staining patterns were detected in the papillomas and laryngeal dysplasias, irrespective of the HPV-status. In addition, the latter lesions generally showed a higher nuclear than cytoplasmic p16(INK4A) immunostaining intensity. In conclusion, our data show that strong nuclear and cytoplasmic p16(INK4A) overexpression is a reliable surrogate indicator for HPV16 in OPSCC and (adjacent) dysplasias. For HPV6 or -11-positive and HPV-negative benign and premalignant lesions of the tonsil and larynx, however, p16(INK4A) immunostaining is highly variable and cannot be recommended to predict HPV-presence.

Association between human papillomavirus infection and laryngeal squamous cell carcinoma

The aim of this study was to compare the prevalence of human papillomavirus (HPV) infection in laryngeal squamous cell carcinoma using two methods: PCR-DNA enzyme immunoassay (PCR/DEIA) and immunohistochemistry (IHC) for detection of HPV in specimens of laryngeal squamous cell carcinoma and to correlate the presence of HPV with the epidemiological and clinicopathological features of recurrence and survival. HPV DNA was amplified from 93 paraffin-embedded laryngeal squamous cell carcinoma tissue specimens by the short PCR fragment (SPF 10) primer set using PCR/DNA method. HPV detection using monoclonal anti-human papilloma virus antibodies Clone K1H8 for IHC reaction was performed on 130 specimens. HPV was identified in 35.5% of patients with laryngeal squamous cell carcinoma using PCR/DEIA and 27.7% using IHC. There was no statistically significant association between the presence of HPV and the epidemiological and clinicopathological features and recurrence. There was no statistically significant association between the presence of HPV and overall survival nor disease specific survival. Statistically significant correlation between HPV detection using PCR/DEIA technique and IHC technique was found. The presence of HPV infection in 27.7% and 38.9% of the patients suggests a possible role in the etiology of laryngeal squamous cell carcinoma. The SPF(10) PCR/DEIA technique is the most accurate method for detection of HPV in laryngeal squamous cell carcinoma.

Human papillomavirus as a risk factor in oral carcinogenesis: a study using in situ hybridization with signal amplification

INTRODUCTION

It is still controversial whether human papillomavirus (HPV) can be considered a risk factor in oral carcinogenesis. The aim of this study was to detect HPV DNA in 50 cases diagnosed as oral leukoplakias, with different degrees of epithelial dysplasia, and as oral squamous cell carcinomas, using in situ hybridization with signal amplification (CSA-ISH).

METHODS

HPV DNA was assessed in paraffin sections using CSA-ISH with a wide-spectrum biotinylated DNA probe. In HPV-positive cases, genotyping with specific probes to HPV types 6/11, 16/18 and 31/33 was performed.

RESULTS

The overall prevalence of HPV infection was 24%, markedly higher than that found in the control group. Results showed a discrete proportional relationship in the indices found in leukoplakia with no dysplasia, leukoplakia with dysplasia, and squamous cell carcinoma, but this was not statistically significant. When separating the group of leukoplakia by degrees of dysplasia, this relation of proportion was not observed. In genotyping, HPV types 16/18 were the most prevalent, and types 6/11 were only found in groups of mild or no dysplasia.

CONCLUSION

The results suggest that HPV is not likely to play a role in the progression of malignant transformation in oral lesions. Nevertheless, the increased prevalence of HPV infection compared to normal oral mucosa and the fact that high-risk HPV types were the most frequently identified do not allow the exclusion of HPV as a risk factor in oral carcinogenesis.

Chapter 7: Human papillomavirus and cancer of the upper aerodigestive tract

We discuss current evidence of the role of human papillomavirus (HPV) in some cancers of the upper aerodigestive tract, including the oral cavity, the pharynx, and the larynx. Cancers of the oral cavity and the pharynx are associated mainly with tobacco and alcohol exposure, but there is evidence from case series, from case-control studies, and from cohort studies that HPV plays a role in a fraction of these cancers, particularly cancer in the oropharynx and tonsil. The HPV type most commonly associated with cancers in these locations is HPV 16. Laboratory evidence indicates that the virus is integrated and that HPV oncogenes are transcriptionally active in these tumors. Many aspects of the association remain to be investigated, including the epidemiology and natural history of HPV infection in the mouth, the role of cofactors, and the potential use of HPV testing and vaccines in the prevention of these tumors. An analogous role for the virus at other anatomic sites in the upper aerodigestive tract such as the larynx is less clear. The relationship between HPV infection and laryngeal cancer is of particular interest, given that recurrent respiratory papillomatosis is clearly caused by benign proliferative growths induced by HPV 6 or 11 infection of the laryngeal epithelium. Although HPV genomic DNA has been detected in a proportion of laryngeal cancers and despite the many efforts made during the last 15 years, there is not yet compelling evidence that HPV plays a substantial role in laryngeal cancer.

Current theories for the development of nonsmoking and nondrinking laryngeal carcinoma

The pivotal risk of smoking and alcohol in laryngeal cancer has meant that evidence for alternate cofactors has been indicative to date. A number of case series, however, contain a few patients who are life-long nondrinkers and nonsmokers and question what other cofactors may contribute. Gastroesophageal reflux disease makes a small but significant contribution to the causal development of laryngeal cancer; however, what remains to be understood is the mechanism of its action. Bile reflux appears to be an additional causative factor in achlorhydrics. After controlling for the effects of alcohol and tobacco, exposure to oncogenic types of human papilloma virus is associated with an increased risk of laryngeal carcinoma. Evidence does not support asbestos exposure itself as increasing the relative risk of laryngeal cancer. A dietary increase in vegetables and fruit may confer an advantage in reducing the laryngeal cancer incidence. Inherited differences in cell cycle control systems, DNA repair systems, and carcinogen-metabolizing enzymes can increase the risk for laryngeal cancer, but as yet, no causal mechanism has been demonstrated.