***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Most squamous cell anal cancers and precancerous lesions are attributed to human papillomavirus ( HPV ) infection . By preventing HPV infection , quadrivalent HPV vaccine ( qHPV ) reduces risk of anal cancer/precancerous lesions in young men who have sex with men ( MSM ) without history of anal cancer/precancerous lesions . In our practice , many persons with history of precancerous anal lesions or high- grade anal intraepithelial neoplasia ( HGAIN ) have been vaccinated electively . We determined whether qHPV is effective at preventing recurrence of HGAIN . METHODS This nonconcurrent cohort study evaluated 202 patients with a history of previously treated HGAIN . Eighty-eight patients were vaccinated , and 114 patients were unvaccinated . We determined the recurrence rate of histologic HGAIN in vaccinated versus unvaccinated patients . RESULTS During 340.4 person-years follow-up , 12 ( 13.6 % ) vaccinated patients and 35 ( 30.7 % ) unvaccinated patients developed recurrent HGAIN . Multivariable hazards ratio ( HR ) analysis showed testing positive for oncogenic HPV genotypes within 8 months before study entry was associated with increased risk of recurrent HGAIN at 2 years after study entry ( HR 4.06 ; 95 % confidence interval [ CI ] , 1.58 - 10.40 ; P = .004 ) , and qHPV was associated with decreased risk of recurrent HGAIN ( HR .50 ; 95 % CI , .26-.98 ; P = .04 ) . Among patients infected with oncogenic HPV , qHPV was associated with decreased risk of recurrent HGAIN at 2 years after study entry ( HR .47 ; 95 % CI , .22 - 1.00 ; P = .05 ) . CONCLUSIONS qHPV significantly reduces HGAIN recurrence  among MSM and may be an effective posttreatment adjuvant form of therapy . A r and omized controlled trial is needed to confirm these results Background Treatment of women for high- grade cervical cancer precursors frequently results in clearance of the associated high-risk human papillomavirus ( hrHPV ) infection but the role of treatment among women without hrHPV is unknown . We investigated whether cervical cryotherapy reduces newly detected hrHPV infections among HIV-positive and HIV-negative women who were hrHPV negative when treated . Methods The impact of cryotherapy on newly detected hrHPV infections was examined among 612 women of known HIV serostatus , aged 35 to 65 years , who were negative for hrHPV DNA , and r and omized to either undergo cryotherapy ( n = 309 ) or not ( n = 303 ) . All women underwent repeat hrHPV DNA testing 6 , 12 , 24 , and 36 months later . Results Among 540 HIV-negative women , cryotherapy was associated with a significant reduction in newly detected hrHPV infections . Women in the cryotherapy group were 55 % less likely to have newly detected hrHPV than women in the control group ( 95 % CI 0.28 to 0.71 ) . This association was independent of the influence of changes in sexual behaviors following therapy ( adjusted hazards ratio ( HR ) = 0.49 , 95 % CI 0.29 to 0.81 ) . Among 72 HIV-positive women , similar reductions were not observed ( HR = 1.10 , 95 % CI 0.53 to 2.29 ) . Conclusions Cervical cryotherapy significantly reduced newly detected hrHPV infections among HIV-negative , but not HIV-positive women . These results raise intriguing questions about immunological responses and biological mechanisms underlying the apparent prophylactic benefits of cryotherapy Objectives To determine the effect of human papillomavirus ( HPV ) quadrivalent vaccine on the risk of developing subsequent disease after an excisional procedure for cervical intraepithelial neoplasia or diagnosis of genital warts , vulvar intraepithelial neoplasia , or vaginal intraepithelial neoplasia . Design Retrospective analysis of data from two international , double blind , placebo controlled , r and omised efficacy trials of quadrivalent HPV vaccine ( protocol 013 ( FUTURE I ) and protocol 015 ( FUTURE II ) ) . Setting Primary care centres and university or hospital associated health centres in 24 countries and territories around the world . Participants Among 17 622 women aged 15–26 years who underwent 1:1 r and omisation to vaccine or placebo , 2054 received cervical surgery or were diagnosed with genital warts , vulvar intraepithelial neoplasia , or vaginal intraepithelial neoplasia . Intervention Three doses of quadrivalent HPV vaccine or placebo at day 1 , month 2 , and month 6 . Main outcome measures Incidence of HPV related disease from 60 days after treatment or diagnosis , expressed as the number of women with an end point per 100 person years at risk . Results A total of 587 vaccine and 763 placebo recipients underwent cervical surgery . The incidence of any subsequent HPV related disease was 6.6 and 12.2 in vaccine and placebo recipients respectively ( 46.2 % reduction ( 95 % confidence interval 22.5 % to 63.2 % ) with vaccination ) . Vaccination was associated with a significant reduction in risk of any subsequent high grade disease of the cervix by 64.9 % ( 20.1 % to 86.3 % ) . A total of 229 vaccine recipients and 475 placebo recipients were diagnosed with genital warts , vulvar intraepithelial neoplasia , or vaginal intraepithelial neoplasia , and the incidence of any subsequent HPV related disease was 20.1 and 31.0 in vaccine and placebo recipients respectively ( 35.2 % reduction ( 13.8 % to 51.8 % ) ) . Conclusions Previous vaccination with quadrivalent HPV vaccine among women who had surgical treatment for HPV related disease significantly reduced the incidence of subsequent HPV related disease , including high grade disease . Trial registration s NCT00092521 and OBJECTIVE To compare the PCR detection rates of high risk human papillomavirus DNA in self-collected urine and cervical scrapes during follow-up of patients treated for HG-CIN by laser CO2 conization .  PATIENTS AND METHODS 52 women who su bmi tted to laser conization for HG-CIN were enrolled into this prospect i ve follow-up study receiving liquid-based cytology and HR-HPV testing by PCR assay on self-collected urine and cervical scrapes before and at 3 , 6 and 12 months after treatment . Diagnostic accuracy and predictive values for treatment failure were evaluated for both urinary and cervical HPV testing and follow-up cytology . RESULTS 3 cases ( 5.8 % ) of recurrent HG-CIN occurred during follow-up . Positive margins and HR-HPV persistence result ed to significant risk factors for recurrence ( p=0.01 ) . The overall concordance on HR-HPV detection between paired urine and cervical sample s was 96.6 % and discord trend between agreement rates during follow-up were excluded by overall fixed-effect index ( OR 1.03 ; 95 % CI 0.62 - 1.70 ) . No difference was observed comparing the three- and six-month cumulative sensitivity and NPV for recurrent disease of urinary and cervical HPV detections , with an increase of 5.6 % in specificity associated with urinary testing . CONCLUSIONS PCR detection of HR-HPV in paired urine and cervical sample s during follow-up revealed an excellent concordance , suggesting a potential equivalent role of the two methods within post-treatment follow-up . In our experience HPV testing on self-collected urine was more sensitive than cytology and more specific than cervical HPV detection to predict treatment failure . Larger studies are needed to definitively establish the role of urine-based HPV testing during follow-up We assessed a possible role for high-risk human papillomavirus ( HPV ) testing in the policy after treatment for cervical intraepithelial neoplasia ( CIN ) 2 or 3 ( moderate to severe dysplasia ) . According to the Dutch guidelines follow-up after treatment consists of cervical cytology at 6 , 12 and 24 months . Colposcopy is only performed in case of abnormal cervical cytology . In this observational study 184 women treated for CIN 2 or 3 were prospect ively monitored by cervical cytology and high-risk HPV testing 3 , 6 , 9 , 12 and 24 months after treatment . Post-treatment CIN 2/3 was present in 29 women ( 15.8 % ) . A positive high-risk HPV test 6 months after treatment was more predictive for post-treatment CIN 2/3 than abnormal cervical cytology ( sensitivity 90 % and 62 % respectively , with similar specificity ) . At 6 months the negative predictive value of a high-risk HPV negative , normal smear , was 99 % . Largely overlapping , partly different groups of women with post-treatment CIN 2/3 were identified by HPV testing and cervical cytology . Based on these results we advocate to include high-risk HPV testing in monitoring women initially treated for CIN 2/3 . In case of a high-risk HPV positive test or abnormal cervical cytology ,  colposcopy  is indicated . All women should be tested at 6 and 24 months after treatment and only referred to the population -based cervical cancer screening programme when the tests are negative on both visits . © 2001 Cancer Research In this controlled prospect i ve study , 14 patients with cervical intraepithelial neoplasia ( CIN ) were observed for one month to exclude spontaneous regression , and then seven patients were treated twice-weekly with perilesional injections of α-interferon . Both groups were monitored colposcopically , and advised to use the contraceptive sheath . Cervical smears and biopsies for histology and viral studies were taken before and after the study . There was an improvement of six out of seven of the study group , with two complete cures . Koilocytosis disappeared if it had been present initially , as did human papillomavirus ( HPV ) 16 . By contrast , three control cases showed improvement , but there were no cures , and one case deteriorated ; Koilocytosis ( 2 cases ) did not change ; HPV 16 disappeared in two controls and appeared in one . A new focus of dysplasia appeared in a part of the transformation zone not being treated with α-interferon in one of the study cases , illustrating the advisability of treating the whole transformation zone in CIN BACKGROUND Cross-sectional human papillomavirus ( HPV ) DNA prevalence peaks at young ages , reflecting sexual acquisition and typically rapid clearance . In some population s , HPV prevalence demonstrates a second peak in older women . Longitudinal data may help to explain this second peak . METHODS We followed a population -based cohort of 7237 women in Guanacaste , Costa Rica , in which we had previously observed a second peak in the baseline HPV prevalence in older women . We tested for > 40 HPV types by polymerase chain reaction . We analyzed age-specific patterns of acquisition and persistence 5 - 7 years after enrollment for individual HPV types . RESULTS At enrollment and follow-up , cross-sectional data revealed U-shaped age-specific HPV prevalence curves for virtually every type , with higher prevalences in the younger and older women than in the middle-aged women . Prospect ively , acquisition of types decreased significantly as women aged ( PTrend<.05 , for both ) , with the highest peak in young women and a secondary minor peak in older women . Type-specific persistence of HPV increased with age ( PTrend<.0001 ) . Overall , HPV acquisition predominated at younger ages , whereas persistent infections gradually became more prominent with age ( PTrend<.0001 ) . CONCLUSIONS Newly apparent infections decreased , whereas persistence increased , with age ; this latter tendency supports the utility of HPV screening in older women OBJECTIVE To assess the use of human papillomavirus genotyping in cervical intraepithelial neoplasia posttreatment follow-up . STUDY DESIGN Prospect i ve observational study . Ninety women underwent cytologic testing and human papillomavirus genotyping at the follow-up visit after conization . Cones were retrospectively genotyped . A second cytologic follow-up was performed . RESULTS Margin status and presence of cervical intraepithelial neoplasia 3 + in the cone were poor predictors of treatment outcome ( sensitivity , < 50 % ; diagnostic odds ratio , < or= 2.5 ) . Presence of high-/intermediate-risk human papillomavirus types predicted 100 % of residual high- grade squamous intraepithelial lesion/cervical intraepithelial 2 + at a specificity of 73 % . Testing only 13 high-risk types showed equal sensitivity but higher specificity ( 86 % ; P < .01 ) . Persistent high-risk human papillomavirus infection ( 13 types 
    Output:
    
Lower HPV incidence was observed among studies that included relatively younger women , used laser conization , focused on HR-HPV rather than overall HPV infection , and had a lower proportion of recurrent cervical disease .