title: HPV-related oropharyngeal carcinoma with Overt Level II and/or III metastases at presentation: The risk of subclinical disease in ipsilateral levels IB, IV and V.
abstract: BACKGROUND
  To assess the risk of subclinical neck nodal involvement of levels IB, IV and V for early T-stage, node positive, human papilloma virus (HPV)-related oropharyngeal carcinoma.
  
  
  METHODS
  We retrospectively identified the patients with clinically positive and un-violated neck that underwent upfront ipsilateral neck dissection for HPV-related oropharyngeal cancer between 1998 and 2010. From the pathology report we extracted the prevalence rate of involvement of each selected level and then estimated the risk that a level that does not contain any node larger than 10 mm at computed tomography (CT) harbors subclinical disease. Predictors of involvement were investigated as well.
  
  
  RESULTS
  Ninety-one patients were analyzed. The risk of subclinical disease in both levels IB and V is < 5%, while it is 6.5% (95% CI 3.1-9.9%) for level IV. Level IB subclinical involvement slightly exceeds 5% when 2 + ipsilateral levels besides IB are involved. The risk of occult disease in level IV tends to be < 5% when level III is not involved.
  
  
  CONCLUSIONS
  These data support the exclusion from the elective nodal volume of level V and level IB but when 2 + other levels are involved. Level IV might also be spared when level III is negative. Clinical implementation within a prospective study is justified.
authors.affiliation: Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University , Baltimore, Maryland , USA.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sanguineti
authors.forename: Sara
authors.initials: S
authors.lastname: Pai
authors.forename: Harold
authors.initials: H
authors.lastname: Agbahiwe
authors.forename: Francesco
authors.initials: F
authors.lastname: Ricchetti
authors.forename: William
authors.initials: W
authors.lastname: Westra
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Sormani
authors.forename: Stefania
authors.initials: S
authors.lastname: Clemente
authors.forename: Joseph
authors.initials: J
authors.lastname: Califano
mesh_terms: D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D037981:Neck Dissection; D009362:Neoplasm Metastasis / Q000473:pathology*; D009367:Neoplasm Staging; D009959:Oropharyngeal Neoplasms / Q000473:pathology* / Q000821:virology; D030361:Papillomavirus Infections / Q000150:complications; D012307:Risk Factors