Investigation On The High-risk HPV Infection And Subtype Distribution Of The Women Sufferers In Chang’an District Of Xi’an City

Background: Cervical cancer is the most common malignant tumor in China andwhich occurs generally during the women over35years old and reaches the peakduring the woman about45-49years old, and in recent years, the illness began toappear in the younger women sufferers. The early detection and effectivetreatment of the cervical cancer may not only protect the health of the sufferersbut save the lives of the patients.In2004, WHO announced that: the current studies show that the high-riskHPV persistent infection is the leading cause for the cervical intraepithelialneoplasia which may further lead to the cervical cancer. In2006, the “EuropeanResearch Organization On Genital Infection and Neoplasia (EUROGIN)”proposed a screening program for the cervical cancer: the Human PapillomaVirus (HPV) gene detection shall be the first choice for screening the cervicalcancer. The Consensus Guidelines for the Management of Women withAbnormal Cervical Cancer Screening Tests issued by the American Society for Colposcopy and Cervical Pathology (ASCCP) clearly indicated that: the womenof30years old shall be subject to the HPV gene subtype detection.International Agency for Research on Cancer of World Health Organizationhas drawn a conclusion that screening period can be extended because of HPVtest’s high sensibility and high negative predicted value. There are enoughevidences showing that HPV test can effectively reduce the morbidity andmortality of cervical cancer. Thus, it can be seen that screening of high-risk HPVis significant to the prevention and treatment of cervical cancer.HPV family has multiple subtypes with about over120kinds in accordancewith the present statistics. Most HPV have no obvious harm on human beings andthey just emerge as one-time infection. Around30kinds of HPV can causegenital tract infection. Among them, more than20kinds relate to thetumorigenesis[1].According to the relation between HPV subtypes and danger ranks of thecervical cancer, it is artificially divided into two types, that is, low-risk type andhigh-risk type. Low-risk HPV (HPV6, HPV11, HPV40, HPV42, HPV44, HPV61,etc.) has no clear relation with the emergence of cervical cancer. It generallycauses some benign pathological changes, for example, genital warts. High-riskPHV has near20decided kinds, including the subtypes of HPV16, HPV18,HPV26, HPV31, HPV33, HPV35, HPV39, HPV45, HPV51, HPV52, HPV55,HPV56, HPV58, HPV59, HPV66, HPV68, HPV82, HPV83, etc. Long-termcontinuous infection can lead to precancerous lesions of genital tract andinfiltrating cancer, for example, cervical epithelial tumor-like lesion and cervicalcancer. Continuous infection of high-risk HPV is the main cause for cervicalprecancerous lesion and cervical cancer, which has been accepted by the public[2]. Infections caused by HPV subtypes are obviously different in varied regions.Many clinical researches show that the commonest subtypes of HPV16, HPV18,HPV56and PHV58have different infection rates among different regions.Cervical cancer caused by HPV52and HPV58have a higher proportion in Asiathan that in African and western countries.All over the world, the morbidity of cervical cancer in China has always stayedat a higher level. In recent years, the morbidity is under the trend of increase.Xi’an is located in the northwest China. The areas around the city are the placesthat have the highest morbidity of cervical cancer in China with their differentfeatures. From the perspective of the protection and treatment of cervical cancer,making clear the distribution and infection proportion of HPV infection subtypesin this region is very important for the screening, prevention and treatment ofcervical precancerous lesion and cervical cancer.Objective：To invest and grasp the conditions of high-risk HPV infection and ofsubtype distribution of the women sufferers in Chang’an District, Xi’an City, andto indirectly reflect HPV infection of women in Chang’an District, Xi’an City. Toinvest distribution of the people who has high-risk HPV infection, and clear thesituation that patients with precancerous lesions of uterine cervix and cervicalcancer to be infected with high-rick HPV in this region, so as to provide clinicalevidence for prevention of future precancerous lesions of uterine cervix andcervical cancer as well as provide data for large-scale HPV infection census inShaanxi Province and Xi’an City, and offer reference for selection of HPVvaccine in this region.Methods: Select the women to visit doctor and make physical examination atXi’an Aerospace General Hospital, Chang’an District Hospital, Chang’an DistrictMaternal and Child Care Service Hospital and521Hospital from September, 2010to February,2012at Chang’an District, Xi’an City‘the baseline for theabove selection: the women who age at18-65, have been married or have hadsexual life more than1year, have no history of conization of cervix orhysterectomy, are not pregnant currently, and have no history of immunologicaldisease or oral immunosuppressor.20,491cases have been checked, such asroutine TCT, application of TBS classification diagnostic criteria and applicationof the second generation Hybrid Capture (HC2) technology for screening ofhigh-rick HPV. High-risk HPV subtype examination has been applied on positivepatients by flexible multi-analyte profiling technology. The investigation wasmade to study the women visit the doctor for women high-risk HPV infection rateand distribution of subtypes in Chang’an District, Xi’an City. At the same time,choose500cases of abnormal TCT examination, all patients received routinecolposcopic examination and biopsy, and then the patients shall be divided intofive groups according to the biopsy Results:Cervicitis, CINI, CINII, CINIII andinfiltrating cancer, so as to count high-risk HPV infection and subtypedistribution of each group.Results: High-risk HPV infection rate of women who visited the doctors inChang’an District, Xi’an City is23.56%, high-risk HPV infection rate of womenwith cervical lesions is47.60%. High-risk HPV subtypes with higher frequencyare HPV16, HPV18, HPV31, HPV33, HPV56and HPV58. The distribution ofHPV high-risk subtype of the women who visited doctors and the distribution ofthe women who have cervical lesions in Chang’an District, Xi’an City have nodifference. Some patients with cervical cancer and CINⅡ~Ⅲ can be diagnosedwith multiple high-risk HPV. Position rate for CINⅠ、CINⅡ~Ⅲ in cervicalintraepithelial neoplasia and high-risk HPV infection patients with cervicalcancer is significantly higher than that of patients with cervicitis; the high-risk HPV infection rate of women under35years old is higher than that of those over35; high-risk HPV infection rate of women in rural is higher than that of those incity; and infection rate in middle and low income group is higher than that ofhigh income group. At the same time, the infection rate of high-risk HPV ishigher in women who have multiple sex partners who did not use condoms, earlymarried and prolific women. With application of card examination, P＜0.05, thedifference has great statistical significance.Conclusion: The high-risk HPV infection rate of women from Xi’an Chang’anDistrict is23.56%, which basically conforms to the high-risk HPV infection rateof normal people reported in China. The high-risk HPV infection rate of womenwith pathology of cervical uteri is47.60%, which is greatly higher than that ofwomen in Xi’an Chang’an District. It can be seen that, screening for high-riskHPV is helpful to make a diagnosis and give treatment for precancerous lesionsof cervical cancer and cervical cancer[3]. The subtype of HPV16,18,31,33,56,58, etc. which the women from Xi’an Chang’an District are suffering from iscomparatively high, and the distributions of subtype16and18are basicallyconsistent when the investigation findings are compared with the world rangedistribution of HPV, but subtypes of HPV33,56and58are comparatively highin local district. The subtypes of HPV18,31and56in local district are relativelyhigher compared with the HPV infection condition in Asia. Compared with thehigh-risk HPV infection in domestic, the subtypes of HPV31,33and56arehigher as well which might be the characteristic of high-risk HPV infection inXi’an Chang’an District. Being clear about the distribution of local HPVinfection rate and the subtype can provide the future prevention and cure of theprecancerous lesions of uterine cervix and cervical cancer with clinicalfoundation and also provide a reliable foundation for researching and making pointed genetic vaccine for researchers. Though the detection on high-risk HPVof the women who went to gynae in Chang’an District, it can indirectly reflect thelocal high-risk HPV infection condition that provides the reference for theselection of HPV vaccine.According to the investigation findings, the high-risk HPV infection rate ofwomen from Xi’an Chang’an District is relatively high among rural women andpeople with low income, early married, proliferation and with frequent sexual life.From the view of the prevention of cervical cancer, we should strengthen thecervical cancer screening among those groups of women, on the one hand,strengthen the communication and education of women cancer prevention andpersonal health to make them understand the dangerous elements and early signalof cervical cancer and nip in the bud. On the other hand, prepare a scientific andreliable screening method such as our plan of current high-risk HPV screeningtogether with the inspection of liquid based cytology, to reach early diagnose andtreatment and reduce the incidence of disease of cervical cancer and death rate.