title: Low prevalence of high risk genotypes of human papilloma virus in normal oral mucosa, oral leukoplakia and verrucous carcinoma.
abstract: OBJECTIVE
  Squamous Cell Carcinoma (SCC) is the most common malignancy of the oral cavity and Verrucous Carcinoma (VC) is its least invasive form with no metastasis potential. Leukoplakia (clinical term for hyperkeratosis and acanthosis with and without dysplasia) is the most common pre-malignant lesion of the oral cavity. Human Papilloma Virus (HPV) has been recognized as an etiologic factor for mentioned lesions. In this study the relationship between high risk types of this virus (HPV(HR)) with VC and Leukoplakia is investigated.
  
  
  METHODS
  Forty-one paraffin-embedded blocks including 21 VC, 20 leukoplakias in addition to 18 normal oral mucosal tissues as the control group were studied by Polymerase Chain Reaction (PCR) to detect HPV 16, 18, 31 and 33.
  
  
  RESULTS
  In three specimens of VCs (14.3%) HPV(HR) was detected. Each of these contained both HPV 16 and 18. All three positive specimens belonged to women older than 65 and were obtained from the vestibule of the mandible. Neither Leukoplakia nor normal mucosa showed HPV presence. No significant relationship between HPV and VC was found compared with the control group (p = 0.23).
  
  
  CONCLUSIONS
  This study did not show relationship between HPV and leukoplakia. Although no statistically significant relationship was found between HPV and VC, but considering sample size limitation for such uncommon cases, its presence in three cases of 14 makes more investigations to overcome the controversies necessary.
authors.affiliation: Dental Research Center, Department of Oral & Maxillofacial Pathology, Faculty of Dentistry, Mashhad University of Medical Sciences, Iran.
authors.forename: Nasrollah
authors.initials: N
authors.lastname: Saghravanian
authors.forename: Kiarash
authors.initials: K
authors.lastname: Ghazvini
authors.forename: Shahab
authors.initials: S
authors.lastname: Babakoohi
authors.forename: Alireza
authors.initials: A
authors.lastname: Firooz
authors.forename: Nooshin
authors.initials: N
authors.lastname: Mohtasham
mesh_terms: D000367:Age Factors; D000368:Aged; D052685:Alphapapillomavirus / Q000145:classification / Q000302:isolation & purification*; D018289:Carcinoma, Verrucous / Q000821:virology*; D016022:Case-Control Studies; D005260:Female; D005838:Genotype; D005887:Gingival Neoplasms / Q000821:virology; D052162:Human papillomavirus 16 / Q000302:isolation & purification; D052161:Human papillomavirus 18 / Q000302:isolation & purification; D058952:Human papillomavirus 31 / Q000302:isolation & purification; D006801:Humans; D007972:Leukoplakia, Oral / Q000821:virology*; D008048:Lip Neoplasms / Q000821:virology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000821:virology*; D009062:Mouth Neoplasms / Q000821:virology*; D030361:Papillomavirus Infections / Q000821:virology*; D016133:Polymerase Chain Reaction; D012737:Sex Factors; D014062:Tongue Neoplasms / Q000821:virology