title: Detection of human papillomavirus in laryngeal squamous cell carcinoma: Systematic review and meta-analysis.
abstract: BACKGROUND
  Recent studies have reported a human papillomavirus (HPV) prevalence of 20% to 30% in laryngeal squamous cell carcinoma (LSCC), although clinical data on HPV involvement remain largely inconsistent, ascribed by some to differences in HPV detection methods or in geographic origin of the studies.
  
  
  OBJECTIVE
  To perform a systematic review and formal meta-analysis of the literature reporting on HPV detection in LSCC.
  
  
  METHODS
  Literature was searched from January 1964 until March 2015. The effect size was calculated as event rates (95% confidence interval [CI]), with homogeneity testing using Cochran's Q and I(2) statistics. Meta-regression was used to test the impact of study-level covariates (HPV detection method, geographic origin) on effect size. Potential publication bias was estimated using funnel plot symmetry.
  
  
  RESULTS
  One hundred seventy nine studies were eligible, comprising a sample size of 7,347 LSCCs from different geographic regions. Altogether, 1,830 (25%) cases tested HPV-positive considering all methods, with effect size of 0.269 (95% CI: 0.242 to 0.297; random-effects model). In meta-analysis stratified by the 1) HPV detection technique and 2) geographic study origin, the between-study heterogeneity was significant only for geographic origin (P = .0001). In meta-regression, the HPV detection method (P = .876) or geographic origin (P = .234) were not significant study-level covariates. Some evidence for publication bias was found only for studies from North America and those using non-polymerase chain reaction methods, with a marginal effect on adjusted point estimates for both.
  
  
  CONCLUSIONS
  Variability in HPV detection rates in LSCC is explained by geographic origin of study but not by HPV detection method. However, they were not significant study-level covariates in formal meta-regression.
  
  
  METHODS
  NA.
authors.affiliation: Department of Surgical Oncology, Head and Neck Surgery, Barretos Cancer Hospital, Barretos, Brazil.
authors.forename: Ricardo Ribeiro
authors.initials: RR
authors.lastname: Gama
authors.affiliation: Department of Surgical Oncology, Head and Neck Surgery, Barretos Cancer Hospital, Barretos, Brazil.
authors.forename: André Lopes
authors.initials: AL
authors.lastname: Carvalho
authors.affiliation: Laboratory of Medical Investigation (LIM) 14, Department of Pathology, University of São Paulo School of Medicine, São Paulo, Brazil.|Life and Health Sciences Research Institute, School of Health Sciences, University of Minho, Braga, Portugal.|ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.|Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.
authors.forename: Adhemar
authors.initials: A
authors.lastname: Longatto Filho
authors.affiliation: Department of Bioestatistics, Barretos Cancer Hospital, Barretos, Brazil.
authors.forename: Anderson Paulo
authors.initials: AP
authors.lastname: Scorsato
authors.affiliation: Oncology Translational Centre, Cancer Institute of São Paulo, São Paulo, Brazil.
authors.forename: Rossana V Mendoza
authors.initials: RV
authors.lastname: López
authors.affiliation: Department of Oral Pathology and Radiology, Institute of Dentistry, University of Turku, Turku, Finland.
authors.forename: Jaana
authors.initials: J
authors.lastname: Rautava
authors.affiliation: Department of Oral Pathology and Radiology, Institute of Dentistry, University of Turku, Turku, Finland.
authors.forename: Stina
authors.initials: S
authors.lastname: Syrjänen
authors.affiliation: Department of Clinical Research, Biohit HealthCare Plc, Helsinki, Finland.
authors.forename: Kari
authors.initials: K
authors.lastname: Syrjänen
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000453:epidemiology / Q000821:virology*; D027383:Papillomaviridae / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000150:complications* / Q000453:epidemiology
keywords: Laryngeal cancer; detection method; geographic region; meta-analysis; meta-regression; papillomavirus; publication bias; study heterogeneity