title: Occult Primary Head and Neck Squamous Cell Carcinoma: Utility of Discovering Primary Lesions.
abstract: Cancer of an unknown primary (CUP) squamous cell carcinoma metastatic to cervical lymph nodes is a challenging problem for the treating physician. Our aim is to determine if identification of the primary tumor is associated with improved oncologic outcomes and/or tumor characteristics including human papilloma virus (HPV) status.
  
  
  
  Retrospective, matched-pairs analysis contrasting 2 cohorts based upon discovery of primary lesion.
  
  
  
  Tertiary teaching hospital.
  
  
  
  Records of 136 patients initially diagnosed as carcinoma of unknown primary were retrospectively reviewed (1980-2010) and divided into 2 cohorts based on discovery of the primary lesion. Primary outcome measures were overall survival and time to recurrence according to Kaplan-Meier analysis. A nested subset of 22 patients in which the primary was discovered were matched to 22 patients remaining undiscovered according to nodal stage and age.
  
  
  
  Discovered lesions were more likely to exhibit HPV positivity (P < .001). Matched-pairs analyses demonstrated that discovery of the primary was associated with better overall survival (HR = 0.125; 95% confidence interval [CI], 0.019-0.822; P = .030). Discovery of the primary was associated with improved cause-specific survival (HR = 0.142; 95% CI, 0.021-0.93; P = .0418) and disease-free survival (HR = 0.25; 95% CI, 0.069-0.91; P = .03).
  
  
  
  HPV positivity is associated with discovery of the primary tumor. Discovery of the primary lesion is associated with improved overall survival, cause-specific survival, and disease-free survival in patients initially presenting as CUP in matched-pair and cohort comparison analyses.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA davisks@upmc.edu.
authors.forename: Kara S
authors.initials: KS
authors.lastname: Davis
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: J Kenneth
authors.initials: JK
authors.lastname: Byrd
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana, USA.
authors.forename: Vikas
authors.initials: V
authors.lastname: Mehta
authors.affiliation: Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Simon I
authors.initials: SI
authors.lastname: Chiosea
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Seungwon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Ferris
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Jonas T
authors.initials: JT
authors.lastname: Johnson
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA VA Pittsburgh Health System, Pittsburgh, Pennsylvania, USA.
authors.forename: Umamaheswar
authors.initials: U
authors.lastname: Duvvuri
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery / Q000821:virology; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009382:Neoplasms, Unknown Primary / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery / Q000821:virology; D027383:Papillomaviridae / Q000302:isolation & purification; D012189:Retrospective Studies; D015996:Survival Rate
keywords: HPV; base of tongue; cervical metastases; human papilloma virus; oropharyngeal; oropharyngeal cancer; squamous cell carcinoma; tonsil; unknown primary; unknown primary tumor