title: Variable genetic alterations and survival in head and neck cancer.
abstract: OBJECTIVE
  To evaluate multiple genetic loci in patients with head and neck cancer to determine if, as in colorectal carcinoma, there is an orderly occurrence of genetic alterations, and if an accumulation of alterations affects patient survival.
  
  
  METHODS
  Cohort study of patients with head and neck cancer in which fresh tissue was retrieved.
  
  
  METHODS
  Academic medical center.
  
  
  METHODS
  Forty-three patients treated surgically for squamous cell carcinoma of the head and neck from 1991 to 1994.
  
  
  METHODS
  The DNA from tumor and healthy tissue was evaluated for loss of heterozygosity at p53, retinoblastoma, and chromosome 16q and for amplification of cyclin D1. The respective RNA was probed for levels of p53, p 16, p21, and p27 messenger RNA. These findings were compared with tumor stage and patient survival.
  
  
  RESULTS
  DNA analysis showed that loss of heterozygosity occurred at p53 in 21% of tumors, at retinoblastoma in 35%, and at 16q in 21%, and that cyclin D1 was amplified in 42%. Messenger RNA levels of the assessed proteins were variably increased and decreased compared with healthy tissues obtained from the same patients with no discernable pattern. There was no correlation between any one of these genetic alterations and overall survival. When patients were analyzed for loss of heterozygosity at p53, retinoblastoma, 16q, or altered cyclin D1 in combination, 19 patients had no detectable alterations, 13 had 1, 6 had 2, and 5 had 3. Single genetic alterations did not affect survival; however, there was a trend toward decreased survival with multiple alterations. The 2-year Kaplan-Meier survival in patients with less than 1 genetic loss was 78% vs 58% in patients with 2 or more losses.
  
  
  CONCLUSIONS
  The lack of a pattern of genetic alterations in head and neck cancer demonstrates that its progression can be mediated by a multitude of pathways, complicating its genetic evaluation. Single genetic alterations do not appear to affect survival; however, when multiple alterations are detected-regardless of combination-survival is affected. This observation lends credence to the theory that multiple genetic alterations contribute to cancer progression; however, the lack of a pattern of this genetic change is a significant obstacle to applying genetic findings to routine cancer therapy.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati Medical Center, Ohio 45267-0528, USA. lyon.gleich@uc.edu
authors.forename: L L
authors.initials: LL
authors.lastname: Gleich
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: P J
authors.initials: PJ
authors.lastname: Stambrook
authors.forename: J L
authors.initials: JL
authors.lastname: Gluckman
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000401:mortality / Q000601:surgery; D002869:Chromosome Aberrations / Q000235:genetics*; D002874:Chromosome Mapping; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000235:genetics / Q000401:mortality / Q000601:surgery; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D010039:Otorhinolaryngologic Neoplasms / Q000235:genetics* / Q000401:mortality / Q000601:surgery; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D012016:Reference Values; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D012333:RNA, Messenger