VALUTAZIONE DELLA COMPRESENZA DEL PAPILLOMAVIRUS (HPV) IN SEDE ORALE E GENITALE IN DONNE CON CITOLOGIA CERVICALE POSITIVA E NEI RISPETTIVI PARTNER

Introduction/Objective The human papilloma viruses (HPVs) are DNA viruses associated with benign and malignant lesions. For gynaecologists, the carcinogenic potential and the necessity of HPV presence for the development of cancer has been understood for decades in relation to the cervix uteri, and for a large portion of other anogenital tumours. The HPVs have been studied in last decades also by many other different specialist due to its role in association with numerous different cancers in several tissues including Head and neck squamous cell cancer (HNSCC) and Oral Squamous Cell Carcinoma (OSCC). HNSCC accounts for more than 7 % of all human cancer types. Despite the development of new surgical techniques and the introduction of multidisciplinary treatments still almost half of the patients decease. For a long time period smoking and alcohol were the main risk factors contributing to HNSCC. Even if a decline in smoking has been registered from '70s till now, the incidence of OSCC is still rising. This might be explained by an increasing of HPV positive tumors. For this reason the women’s HPV-positive cervix is discussed to act as a virus reservoir. However, until today it remains unclear if the women’s HPV-positive cervix uteri really serves as a virus reservoir and if certain sexual practices are the cause for HPV transmission to the oropharynx. Data on genotype-specific concordance of oral-oral and genital-oral HPV infections among heterosexual couples are key to understand HPV transmission between partners. This study aimed at assessing the concurrence of oropharyngeal HPV infection, with relative genotyping, in women with cervical lesions and in their current stable sexual partners in an Italian population. Material and methods 105 female subjects with a positive PAP test were enrolled in this study. Complete datas, cervical brush, oral swab, oral rinse and urine (only male) samples were collected from 44 women and 28 men. Demographic and behavior data were obtained through a structured questionnaire. HPV-DNA amplification was performed by polymerase chain reaction assay (PCR) using both primers MY09/MY11 and FAP59/64. HPV genotyping has been performed with Sanger technique and each sequence compared with the Finch software and "The PapillomaVirus Episteme" (PaVE) database. Positive samples have been analyzed also with the Inno-Lipa Genotyping Extra kit in order to have an higher accuracy in case of multiple genotype infections. Different variables were considered for the statistical analyses: gender, age, number of partners, oral sex, alcohol consumption per week, lesions etc. The effect of the variables on the HPV infection status was assessed, by fitting a generalized model, using the GLM (General Linear Model) function in R software. The family “binomial” was used for the description of the error distribution and link function. The function fisher test was used to perform Fisher’s exact test as a verification test. The model was tested using the maximum likelihood to evaluate the effect of the inclusion of each parameter to the model. As a supplementary analysis, the correlations were calculated between all parameters. Results 86% of cervical samples were HPV-positive. Different genotypes have been isolated (i.g. 6, 66, 39, 16, 31, 56, 42, 58, 114, 59, 61, 68, 45, 35, 33 e 53, 89, 114). 20% of the oral samples were positive in the female group and 25% in the male one. Only one sample of urine was positive and the same HPV genotype has been found in the cervical brush of his female partner. No other specific genotype concordance has been found between female and male couples. The regression of the variables against the total infection status highlighted three significant factors: gender, oral sex and alcohol (p value: 0,000224, 0.0119 and 0.0362 respectively). This finding shows that males and females are different in what concerns the HPV infection; the oral sex is associated with HPV infection and third that alcohol consumption seems to have a negative effect on HPV infection status. Other variables such as the number of partners, number of sexual rapports, age or use of bird controls pills do not seems to be significant. The regression of the variables against the oral infection status shows that gender is a significant factor (p value 0.04517) but not oral sex and alcohol. Age and smoking although not significant show a trend close to significance (p value 0.0885 and 0.0901 respectively). Moreover, the analyses highlighted that oral sex and alcohol are significant factors for the cervical infections (p value 0.0492 and 0.0229 respectively). The number of partners, the use of bird control pills, smoking and age seem do not to have an effect on cervical infections. As a second step, we divided the data into males samples and females samples. Subsequently, we did two regressions using the two datasets subsets. We found that oral sex is highly significant in women but only suggestively significant in men for HPV infection. In our study oral sex was about three times more common in men than in women. Moreover, in men the number of the partners and the number of sexual rapport seem to have an effect on oral HPV infection (p value 0,0514 and 0,08 with a trend close to significance respectively). As the sample size is relatively low we checked and confirmed the significance of the oral sex and alcohol association using the Fisher exact test. We calculated also the correlations between all the parameters which gives some important biological considerations. Correlation between oral sex and cervical infection was significant (p value 0.04001). Conclusions The limited data suggest that among sexual partners in Italy, HPV transmission to the oropharynx by oral–genital sex or by autoinoculation is a rare event with low HPV concordance. An interesting result is that an asymptomatic HPV infection was common in both spouses while genotype-specific concordance was low. The presence of the virus in both male and female oral mucosa was detected in over 20% of the subjects suggesting an important presence of the virus even if the direct correlation with the cervical infection is still not clear. The presence of the virus in the urine of the male partners was detected only in one case suggesting a low transmission of the virus from the cervical site to the male genital mucosa. Alcohol consumption, oral sex practice and higher number of sexual partners seems to be associated with the presence of the virus.