title: Co-overexpression of p21 and Ki-67 in head and neck squamous cell carcinoma relative to a significantly poor prognosis.
abstract: BACKGROUND
  Head and neck squamous cell carcinomas (HNSCC) are treated by surgery or radiotherapy. Tumor cell death-related markers, such as p21 and Ki-67, may predict response to therapy and improve treatment choice. We evaluated and compared the effect of their coexpression between patients treated by surgery or radiotherapy.
  
  
  METHODS
  Immunohistochemistry for p21 and Ki-67 expression in 144 pharyngeal and laryngeal HNSCC samples was analyzed and correlated with follow-up parameters.
  
  
  RESULTS
  p21 expression correlated significantly with positive cN classification (p < .001), locoregional relapse (p = .031), and poor overall survival (p = .016), and Ki-67 positivity with poor survival only (p = .025). Coexpressing tumor phenotypes showed the worst survival (p = .009), observed primarily in patients treated by radiotherapy (p = .077).
  
  
  CONCLUSIONS
  Coexpression of p21/Ki-67 is a strong negative prognostic factor in HNSCC and could be of particular relevance in tumors treated by primary radiotherapy.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University Hospital, Basel, Switzerland. cfischer@uhbs.ch
authors.forename: Claude A
authors.initials: CA
authors.lastname: Fischer
authors.forename: Minoa
authors.initials: M
authors.lastname: Jung
authors.forename: Inti
authors.initials: I
authors.lastname: Zlobec
authors.forename: Edith
authors.initials: E
authors.lastname: Green
authors.forename: Claudio
authors.initials: C
authors.lastname: Storck
authors.forename: Luigi
authors.initials: L
authors.lastname: Tornillo
authors.forename: Alessandro
authors.initials: A
authors.lastname: Lugli
authors.forename: Markus
authors.initials: M
authors.lastname: Wolfensberger
authors.forename: Luigi M
authors.initials: LM
authors.lastname: Terracciano
mesh_terms: D014408:Biomarkers, Tumor / Q000096:biosynthesis; D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000378:metabolism* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000096:biosynthesis*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006258:Head and Neck Neoplasms / Q000201:enzymology / Q000378:metabolism* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000378:metabolism*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016019:Survival Analysis; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; D050759:Cyclin-Dependent Kinase Inhibitor p21; D019394:Ki-67 Antigen; D047428:Protein Kinase Inhibitors