title: Prevention of recurrent high-grade anal neoplasia with quadrivalent human papillomavirus vaccination of men who have sex with men: a nonconcurrent cohort study.
abstract: 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 randomized controlled trial is needed to confirm these results.
authors.affiliation: Department of Preventive Medicine, Mount Sinai School of Medicine, New York, New York 10011, USA.
authors.forename: Kristin A
authors.initials: KA
authors.lastname: Swedish
authors.forename: Stephanie H
authors.initials: SH
authors.lastname: Factor
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Goldstone
mesh_terms: D000328:Adult; D000368:Aged; D001005:Anus Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000517:prevention & control*; D015331:Cohort Studies; D006651:Histocytochemistry; D018451:Homosexuality, Male; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; D006801:Humans; D008297:Male; D008875:Middle Aged; D030361:Papillomavirus Infections / Q000150:complications* / Q000453:epidemiology / Q000517:prevention & control; D053918:Papillomavirus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D055502:Secondary Prevention; D014611:Vaccination / Q000379:methods*; D055815:Young Adult
chemical_list: D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; D053918:Papillomavirus Vaccines