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

Human papillomavirus (HPV) in head and neck cancer

The term "head and neck cancer" has been widely adopted in the recent literature, to include the lesions at several anatomic sites: the lip, oral cavity, nose and para-nasal sinuses, naso-pharynx, oro-pharynx, hypo-pharynx, and larynx. In this communication, the data on human papillomavirus (HPV) involvement in oral, oro-pharyngeal, sino-nasal, and laryngeal carcinomas are reviewed. Our group was the first to present evidence on the involvement of HPV infections in both laryngeal and oral carcinogenesis, prompted by the discovery of morphological similarities between oral and cervical squamous cell lesions. The latest meta-analyses of the epidemiological studies as well as the multi-centre case-control studies have confirmed HPV as an independent risk factor for oral cancer, with a range of odds ratios (OR) between 3.7 and 5.4. Until 2002, 4768 oral carcinomas have been analysed for HPV DNA, and 22% were reported to contain HPV by any of the detection techniques. Of all non-genital cancers, tonsillar carcinomas appear to have the highest prevalence of HPV. By the end of 2002, 422 cases of tonsillar carcinoma have been analyzed for the presence of HPV DNA, with the overall detection rate of 51%. HPV 16 is the most prevalent HPV type found in 84% of HPV DNA-positive tumours. HPV seems to be mainly episomal in tonsillar carcinomas, but the significance of this observation is still obscure. Interestingly, patients with HPV 16-positive tumours seem to have a better overall- and disease-specific survival, as compared with the HPV-negative group. To date, 1041 sino-nasal papillomas have been analysed for HPV and 347 (33%) cases have been positive, whereas of the 322 sino-nasal carcinomas analysed so far, 70 (22%) have been positive for any HPV type. Laryngeal squamous cell papilloma and recurrent respiratory papillomatosis (RRP) are well-established HPV-induced tumours, whereas the role of HPV in laryngeal carcinomatosis remains controversial. The molecular mechanisms of HPV-associated carcinogenesis of the head and neck require further study.

Oral cancer; the evidence for sexual transmission

The incidence of oral cancer amongst young adults is increasing in many European and high incidence countries. Most oral cancer is aetiologically linked to the use of tobacco and/or alcohol but nearly two decades ago, we produced the first evidence for the presence of viral nucleic acids in oral squamous cell carcinoma (OSCC) tissues, hypothesising that there may be a viral involvement in at least some OSCC. Subsequently, human papillomaviruses (HPV) in particular have been implicated in OSCC. Antibody responses to HPV are seen and HPV-DNA detected in tumours by us and many others, the virus being mainly HPV-16, the genotype associated with ano-genital cancer. Recent studies have indicated that HPV may be aetiologically important particularly in some types of oropharyngeal cancer, at least in tonsillar carcinogenesis, and may represent an alternative pathway in carcinogenesis to the established factors of tobacco and alcohol. Studies of patients with OSCC have suggested possible sexual transmission of HPV.

Females with paired occurrence of cancers in the UADT and genital region have a higher frequency of either Glutathione S-transferase M1/T1 null genotype

Upper Aero digestive Tract (UADT) is the commonest site for the development of second cancer in females after primary cervical cancer. Glutathione S-transferase (GSTM1 and / or T1) null genotype modulates the risk of developing UADT cancer (primary as well as second cancer). The aim of this study was to evaluate the difference in GST null genotype frequencies in females with paired cancers in the UADT and genital region as compared to females with paired cancers in the UADT and non-genital region. Forty-nine females with a cancer in the UADT and another cancer (at all sites-genital and non-genital) were identified from a database of patients with multiple primary neoplasms and were analyzed for the GSTM1 and T1 genotype in addition to known factors such as age, tobacco habits, alcohol habits and family history of cancer. Frequencies of GSTM1 null, GSTT1 null, and either GSTM1/T1 null were higher in females with paired occurrence of cancer in the UADT and genital site (54%, 33% and 75% respectively) in comparison to females with paired occurrence of cancer in the UADT and non-genital sites (22%, 6% and 24% respectively). The significantly higher inherited frequency of either GSTM1/T1 null genotype in females with a paired occurrence of cancers in UADT and genital region (p = 0.01), suggests that these females are more susceptible to damage by carcinogens as compared to females who have UADT cancers in association with cancers at non-genital sites.

Detection of various types of human papillomavirus DNA, mainly belonging to the cutaneous-group, more frequently in normal tissue than in squamous cell carcinomas of the lip

BACKGROUND

Mucosal high-risk human papillomaviruses (HPVs), such as type 16, are detectable in oral cancers, especially of the oropharynx and tonsils, and there is evidence that they play a pathogenetic role in some cases. However, information is limited about their significance for cancers of the vermilion of the lip.

OBJECTIVE

To determine the detection rate, types and localization of HPVs in squamous cell carcinomas (SCCs) of the lip.

METHODS

Nested PCR for cutaneous HPVs, including epidermodysplasia verruciformis-related HPV (EV-HPV), and single PCR for mucosal HPVs, were conducted for a total of 27 SCCs and normal samples from 30 individuals. Tyramide-based in situ hybridization (ISH) was also applied.

RESULTS

Various types of HPVs were detected, particularly from normal individuals. Among the kinds of the HPV types detected in this study, half were found by PCR using a primer pair, which we newly designed. The prevalence of HPV was 5 out of 27 SCCs (ca. 18%) and 10 out of 30 normal individuals (ca. 33%). They were the entire cutaneous-group except for two, from one SCC and one normal individual.

CONCLUSION

On the surface of the normal lip various types of mainly cutaneous-group HPVs may be present, but there does not appear to be any obvious association with SCCs developing in this site.

Gender difference in human papillomarvirus infection for non-small cell lung cancer in Taiwan

Our previous reports have indicated that high risk human papillomarvirus (HPV) 16/18 were much more frequently detected in lung tumors of female patients as compared to that of male patients and HPV 16/18 in lung tumors were evolutionally correlated with those in blood circulation. In the other hand, it is well known that HPV 6/11 are frequently associated with upper aerodigestive and respiratory diseases. HPV 6/11 DNA were detected in lung tumors by nested PCR and in situ hybridization to investigate if any difference in prevalent types of HPV exists between genders. Our data showed that HPV 6 infection was detected in 28.4% (40 of 141) lung tumors, which was significantly higher than that in non-cancer controls (1.7%, 1 of 60; P < 0.0001), however, such high prevalence was not observed for HPV 11. Among studied clinico-pathological parameters, HPV 6 infection was significantly related with gender (P = 0.002) and smoking status (P = 0.014). After being stratified by gender and smoking status, HPV 6 infection rate in lung tumors of non-smoking male patients was much higher than that in non-smoking female patients (33.3% versus 11.1%; P = 0.023), but no difference between smoking and non-smoking male patients (38.1% versus 33.3%). With adjustments for age, tumor type, and tumor stage, smoking male lung cancer patients had a much higher OR value (OR, 7.35; 95%CI, 2.11-25.58) for HPV 6 infection compared with 3.93 (95% CI, 1.17-13.12) of non-smoking male patients. Moreover, a higher prevalence of HPV 6 was detected in lung tumors of smoking male patients with early tumor stage than those with advanced stages (P = 0.008), but not in non-smoking male and female patients. A higher prevalence of HPV 6 in male lung cancer patients, as compared with female lung cancer patients, indicating not only different HPV infection routes for different genders, but also that HPV 6 infections may act as a prospective early risk marker of lung cancer for smoking male patients in Taiwan.

Épidémiologie des carcinomes des voies aérodigestives supérieures

Head and neck carcinomas, i.e. oral cavity, pharynx and larynx cancers, are frequent among men in France. They are mostly squamous-cell carcinomas. The main risk factors are alcohol and tobacco, and their effects are multiplicative. In France, alcohol and tobacco consumptions are decreasing in the male population leading to decrease in head and neck carcinoma incidence and mortality. The best way to prevent head and neck carcinoma is the reduction of alcohol and tobacco consumption.

Profiling early head and neck cancer

Head and neck squamous-cell carcinoma (HNSCC) is the sixth most common cancer worldwide and, disappointingly, survival rates are not improving. Moreover, HNSCC has a severe impact on the quality of life of patients and survivors, and the significant morbidity subsequent to treatment often mandates long-term multidisciplinary care, which places significant financial pressures on the treating institution. Therefore, prevention and early diagnosis of high-risk pre-malignant lesions are high priorities for reducing deaths due to head and neck cancer. Recent advances have begun to elucidate the different aetiologies of HNSCCs in relation to previous pre-malignancies and to identify which pre-malignant lesions are likely to progress to malignancy.

Human papillomavirus in head and neck cancer: Molecular biology and clinicopathological correlations

Human papillomaviruses are known to cause cancers of the cervix and other anogenital tract sites. Epidemiologic and molecular pathology studies have also suggested that HPV infection may be associated with cancers of the head and neck. Modes of transmission of HPV infection in the head and neck region have not been fully resolved; however, perinatal transmission and an association between sexual behavior and risk for HPV-positive cancers have been presented. Among the HPV types infecting the mucosa, high-risk, intermediate-risk and low-risk genotypes are defined, depending on their presence in carcinoma or precursor lesions. The phylogenic groups of HPVs also showed a definite correlation with the morphology of head and neck tumors. The groups A6, A7, and A9 include viruses that are frequently demonstrated in basaloid and verrucosus squamous cell carcinomas known to associate with HPV infection. Integration of HPV DNA into the host cell genome occurs early in cancer development and is an important event in malignant transformation. There is a trend for patients with HPV-positive tumors to be nondrinkers or light drinkers, the majority of these patients are females, and the median age is lower than in the case of HPV-negative tumors, but this latter difference was not always statistically significant. In the Kaplan-Meier survival model, the HPV-positive verrucous and basaloid squamous cell carcinomas showed better survival rates than the HPV-negative typical squamous cell carcinomas. An increased radiocurability of HPV-positive head and neck squamous cell carcinoma (HNSCC) has also been demonstrated.

The epidemiology of laryngeal cancer in Brazil

The city of São Paulo exhibits one of the highest incidences of laryngeal cancer in world and Brazil presents remarkable occurrence, compared with other Latin American countries. Around 8,000 new cases and 3,000 deaths by laryngeal cancer occur annually in the Brazilian population. In the city of São Paulo, incidence rates for laryngeal cancer among males have been decreasing since the late 1980s while, among females, the rates have shown a stable trend. This phenomenon is probably the expression of changes in gender behavior related to tobacco smoking. Several risk factors are involved in the genesis of laryngeal cancer. The most important are tobacco smoking and alcohol intake, but occupational hazards have also been associated with the disease, such as asbestos, strong inorganic acids, cement dust and free crystalline silica. Additionally, salted meat and total fat intake have been linked to elevated risk of laryngeal cancer. Conversely, several studies have confirmed that fruits, raw leaf vegetables and legumes protect against this cancer. Some researchers have postulated a possible association between laryngeal squamous cell carcinoma and human papilloma virus (HPV), but this is not universally accepted. Gastroesophageal reflux disease is weakly, but consistently correlated with laryngeal cancer. Familial cancer clusters, particularly of head and neck tumors, seem to increase the risk of laryngeal cancer. Some genetic polymorphisms, such as of genes that code for xenobiotic-metabolizing enzymes, have shown elevated risk for laryngeal cancer according to recent studies. Public health policies regarding the control of tobacco smoking and alcohol consumption, and also surveillance of carcinogen exposure in occupational settings, could have an impact on laryngeal cancer. No proposals for screening have been recommended for laryngeal cancer, but one diagnostic goal should be to avoid treatment delay when suspected symptoms have been observed.

Low prevalence of HPV infection and its natural history in normal oral mucosa among volunteers on Miyako Island, Japan

OBJECTIVE

To investigate the prevalence of human papillomavirus (HPV) infection in normal oral mucosa, and to observe the natural history in the oral cavity in oral swab samples collected from healthy volunteers on Miyako Island, Okinawa, Japan.

STUDY DESIGN

The prevalence of HPV infection in oral buccal mucosa cell scrapes collected between 2000 and 2002 from a cohort of 668 healthy volunteers was determined. HPV DNA was detected by consensus polymerase chain reaction (PCR) using MY09/MY11 primers followed by direct cycle sequencing. Just over 2 years later the HPV-positive participants were reevaluated.

RESULTS

Of the 668 subjects, 662 samples were analyzed for HPV. HPV DNA was detected in 4 (0.6%) specimens. HPV type 16 (HPV16), HPV53, and HPV71, mucosal types, and HPV12, a cutaneous type, were all identified by direct sequencing. In the follow-up survey, the HPV71- and HPV12-positive participants again tested positive, while HPV DNA was not detected in the HPV16- and HPV53-positive participants.

CONCLUSION

The results of this study among healthy individuals from Miyako Island suggest that oral HPV infection is uncommon. In this cohort, HPV71 and HPV12 were persistent, while HPV16 and HPV53 were transient in normal oral mucosa.