Human Papillomavirus Type-distribution And The Risk Factors Of Its Infection In384Cases Of Cervical Leision In Henna Provence

Background and ObjectiveCervical cancer is more common cancer in women. High risk human papillomavirus infection is the main reason for this disease. In recent years, along with the greatly enhance of its biology and epidemiology, HPV as primary pathogenic agent for the cervical intraepithelial lesions have been widely accepted. HPV is a highly variabl non-enveloped, icosahedral DNA virus that replicates in the nucleus of squamous epithelial cells.The viral particles consis of8000bp. It is a double-sranded circular DNA molecule. Depending on their potential to induce invasivecancer, genital HPV types were classified into high-risk types and low-risk types.Based on Munoz’s recent reseach, HPV types16,18,31,33,35,39,45,51,52,56,58,59,68,73, and82have been classified as high risk HPV (HR-HPV) and HPV26,53and66as potentially high risk HPV(probably HR-HPV), whereas HPV6,11,40,42,43,44,54,61,70,72,81and89are classified as low risk HPV(LR-HPV).HR-HPV are significantly associated with high grade cervical lesions, LR-HPV main associated with genital wart and low grade cervical lesions. Epidemiological data shows:some specific types can result in invasive cervical cancer or can cause persisting infection to induce to malignancy. Even, some types with potential carcinogenicity can be used as prediction indicator for progression of cervical lesion in the early stage. So, it is important to identify HPV gene types for next administration and treat of this disease. Though HPV16/18is the most common type worldwide, some evidence shows other types also have strong carcinogenicity and the genetypes have regional differences.So, it has great significations to indentify HPV genotype in certain region.In recent20years, cervical cancer prevention and control measures has been greatly improved, now the prevention of the cervical cancer is gradually developing from secondary prevention to the early primary prevention. That is from early treatment to prevent HPV infection. So the detecting of HPV genotype can provide the bases for the vaccine. Currently, there are two available vaccines:one is quadrivalent consist of HPV16,18,6,11, the other is a bivalent vaccine consist of HPV16,18.These two vaccines were invented according to the Europe HPV genotype epidemiological information, and the cross prevention of these vaccines is limited. AS the HPV genotypes have the distribution difference, the vaccine invention should consider the distribution difference of HPV. To assess the association between HPV genotypes and cervical lesion and the benefit of the vaccines, it is necessary to test the genotype in difference district.China is a vast country with a large population, there must be different HPV types in different area. We don’t know the the prevalent genotypes of HPV in Henan Province now, so this research on HPV genotypes in Henan province can give the Henan even China the data of HPV infection and provide the basis for the vaccine invention.It is necessary to have a persistent infection of the cervix with a high-risk or oncogenic HPV (hrHPV) virus to develop cervical cancer. But it is not sufficient; other associated co-factors are required as well. These co-factors may improve either HPV persistent infection or the progression of cervical leision after HPV infection. Beause the HPV genetypes has the region difference, the risk factors of HPV infection was also different in different area. Though there is more risk factors report about cervical cancer, the risk factors in Henan have not been reported. This reseach on risk factors of HPV infection in Henan province can give the Henan the data on preventing the cervical cancer and provide the basis for valuating the vaccine effect. Materials and method1Objects524cases conducted the specific Thinprep cell test (TCT) detection from August2009to April2011in our hospital were selected to conducted HPV genetypes detection. These samples contain108cases of Negative for Intraepithelial Lesion or Malignancy (NILM),105cases of Atypical Squamous Cells of Undetermined Signification (ASCUS),126cases of Low-grade squamous Intraepithelial Lesion (LSIL),101cases of High-grade squamous Intraepithelial Lesion (HSIL) and84cases of Squamous Cells cancer (SCC). The residual liquid specimens were collected for testing HPV genetypes. Meanwhile, the questionnaire of the risk factors of HPV infection and information consent form should be filled in by the patients who joined in our research and will conduct the HPV genetypes testing.2Methods2.1CytodiagnosisFirstly, the TCT brush was used to collect cervical exfoliated cells. Then the brush should be washed in dip and repeatedly in the TCT cells preservation liquid to assure that the cell can be wash down completely. Secondly, the ThinPrepR2000was used to make smears. Then these smears were fixed in95%alcohol. Thirdly, Papanicolaou staining was used to stain these fixed smears. Gums seal them after staining. Lastly, the smears were read under light microscope and diagnosed according to the TBS system when they were air dry.2.2The test of HPV genetypesFirstly, DNA was extracted from samples. Secondly, the DNA was PCR amplified. Lastly, the samples were tested with xMAP technology with Luminex200.2.2The questionnaire of risk factorsThe questionnaire and information consent form of HPV risk factors were made by trained professional person. Questionnaires were filled in by patients by voluntary principles. Questionnaire content includes:personal information, demography material, the history of releated disease, smoking history, reproductie history, history of contraception, sexual history and health habits, the results of cytology, pathology and HPV. 3Statistics analysisThe data obtained from the statistical analysis with SPSS17.0, the incidence of HPV infection among different cytology result were analysised with R x C column league table by the chi-square test or Fisher exact probability method, the significant level α was0.05; HPV infection risk factors were analysised by monovariate and multivariate non-conditional logistic analysis, the significant level α was0.05Results1The incidence of HPV genotype in each lesion of cervical cytopathology(1) The percent of each group:At last, only384cases were valid. There were84cases (21.9%) with Negative for Intraepithelial Lesion or Malignancy and300cases (78.1%) with cervical squamous intraepithelial lesion in these valid cases. There were80cases (20.8%) in ASCUS group,100cases (26.0%) in LSIL group,70cases (18.2%) in HSIL group and50cases (13.0%) in SCC group.(2) In all groups, there were300cases with HPV positive and the positive rate was78.1%(300/384). Single type was64.8%(249/384), multiple type was13.3%(51/384). High risk HPV was72.7%(279/384), low risk HPV was8.9%(34/384). The most common genotypes were HPV16,52,58,33,18.(3) In the NILM group, there were48cases with HPV positive and the incidence was57.1%. Single type was42.9%(36/84) and multiple type was14.3%(12/84).The most common genotypes were HPV16,6,52,58,31,39.(4) In ASCUS group, the incidence of HPV was72.5%(58/80). The single type rate was52.5%(42/80) and the multiple type rate was20.0%(16/80).The most common genotypes were HPV16,52,18,58.(5) In LSIL group, the incidence of HPV was84.0%(84/100). Single type was77.0%(77/100) and multiple type was7.0%(7/100). The most common genotypes were52,6,16,58.(6) In HSIL group, the incidence of HPV was88.6%(62/70) Single type was74.3%(52/70) and multiple type was14.3%(10/70). The genotypes were16,33,58,51. (7) In SCC group, the incidence of HPV was96.0%(48/50). Single type was84.0%(48/50), multiple type was12.0%(6/50). The genotypes were HPV16,18,58,33and52.2The risk factors of HPV infectionUnivariate Logistic regression analysis showed there were associations between risk factors for HR-HPV infection and education level, socio-economic state first marriage age, passive smoking, ever pregnant, artificial abortion, condom use, age at first intercourse and the number of sexual partner (P<0.05). The risk factors for HR-HPV infection included passive smoking, artificial abortion and the number of sexual partner(OR>1); Multivariate Logistic regression analysis showed lower socio-economic state, junior at first intercourse, passive smoking and artificial abortion were risk factors (P<0.05)Conclusion1. The incidence of HPV was increased when cervical lesion grade was up.2. The high risk and single genotypes were predominantly infected in different groups of cervical squamous intraepithelial lesion in Henan province.3. HPV16was the most frequent HPV genotypes in Henan province, then HPV52,58,33were more common and HPV18was less common in fourth place in all these cases in Henan province.4. HPV16were the most common genotypes in HSIL and SCC, then was HPV33, followed were HPV18,58in Henan province.5. The risk factors for HR-HPV infection included lower education lever, lower socio-economic income, passive smoking, artificial abortion, the younger first intercourse age and the number of sexual partner(OR>1).