title: High-resolution anoscopy in the diagnosis of anal cancer precursor lesions in renal graft recipients.
abstract: BACKGROUND
  Renal graft recipients are one of the population groups known to be at high risk of developing anal cancer. This study investigated the presence of subclinical anal squamous intraepithelial lesions and the diagnostic ability of high-resolution anoscopy in detecting these lesions in renal graft recipients followed-up in Manaus.
  
  
  METHODS
  In a cross-sectional study, 50 renal graft recipients were interviewed and submitted to high-resolution anoscopy with biopsies of acetowhite lesions or of the anal transition zone mucosa when acetowhitening was absent. Considering the histopathological reports of the examined anal specimens as the gold standard, the diagnostic validation and precision measures of high-resolution anoscopy were calculated as well as the prevalence of anal squamous intraepithelial lesions in the studied population.
  
  
  RESULTS
  In 42 renal graft recipients with satisfactory histopathological readings, prevalence of anal squamous intraepithelial lesions or condyloma acuminatum (ASIL-ACU) was 23.81%. Sensitivity of high-resolution anoscopy was 100%; specificity, 65.63%; positive predictive value, 47.62%; negative predictive value, 100%; and kappa coefficient, 0.48.
  
  
  CONCLUSIONS
  With a prevalence of 23.81% of subclinical ASIL-ACU lesions, the studied renal graft recipients had all these lesions detected by high-resolution anoscopy, notwithstanding most anal transition zone acetowhitened biopsied areas did not reveal histopathological aspects of anal cancer precursor lesions or condyloma acuminatum. Therefore, greater experience with the diagnostic tool was felt necessary to enhance its positive predictive value, specificity and diagnostic precision.
authors.affiliation: Department of Surgery, School of Medicine, Federal University of Amazonas, Rua Afonso Pena, 1053, Manaus, Amazonas, 69020-160, Brazil. itramujas@ufam.edu.br
authors.forename: Ivan
authors.initials: I
authors.lastname: Tramujas da Costa e Silva
authors.forename: Luiz Carlos
authors.initials: LC
authors.lastname: de Lima Ferreira
authors.forename: Felicidad
authors.initials: F
authors.lastname: Santos Gimenez
authors.forename: Ricardo Alexandre
authors.initials: RA
authors.lastname: Gonçalves Guimarães
authors.forename: Luciana
authors.initials: L
authors.lastname: Botinelly Fujimoto
authors.forename: Celso Rômulo
authors.initials: CR
authors.lastname: Barbosa Cabral
authors.forename: Renzo
authors.initials: R
authors.lastname: Venturim Mozzer
authors.forename: Larissa
authors.initials: L
authors.lastname: de Souza Atala
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000473:pathology*; D001005:Anus Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D003430:Cross-Sectional Studies; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D015995:Prevalence; D011379:Prognosis; D012680:Sensitivity and Specificity; D012812:Sigmoidoscopy