title: Ki-67 expression predicts radiotherapy failure in early glottic cancer.
abstract: BACKGROUND
  Early-stage laryngeal squamous cell carcinoma is managed with radiotherapy or endoscopic surgery. Although cure rates are high, radiation failures often require total laryngectomy for salvage. Biomarkers that can predict tumour radioresistance may be useful in modifying the treatment approach for individual patients.
  
  
  METHODS
  Retrospective patient chart review yielded 75 patients with T1-T2 glottic squamous cell carcinoma treated with radiation therapy at the London Health Sciences Centre. Pretreatment tumour biopsies were immunostained for B-cell lymphoma 2 (Bcl-2), Ki-67, and epidermal growth factor receptor (EGFR) to correlate biomarker expression with disease-free survival (DFS).
  
  
  RESULTS
  Ki-67 expression was strongly associated with recurrence following radiation and independently predicted poor DFS (hazard ratio 4.86, 95% CI 1.58-15.00; p  =  .006). EGFR and Bcl-2 were not associated with a risk of recurrence.
  
  
  CONCLUSIONS
  Ki-67 expression identified a subset of patients with increased risk of local recurrence after radiation therapy. Ki-67 expression can potentially guide improved personalized treatments for patients with early-stage glottic squamous cell carcinomas.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, The University of Western Ontario, London, ON N6A 5W9. Anthony.Nichols@lhsc.on.ca
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Nichols
authors.forename: Fiona
authors.initials: F
authors.lastname: Whelan
authors.forename: John
authors.initials: J
authors.lastname: Basmaji
authors.forename: Sandeep
authors.initials: S
authors.lastname: Dhaliwal
authors.forename: Samuel
authors.initials: S
authors.lastname: Dowthwaite
authors.forename: Corina
authors.initials: C
authors.lastname: Chapeskie
authors.forename: Nancy
authors.initials: N
authors.lastname: Read
authors.forename: David A
authors.initials: DA
authors.lastname: Palma
authors.forename: Kevin
authors.initials: K
authors.lastname: Fung
authors.forename: Varagur
authors.initials: V
authors.lastname: Venkatesan
authors.forename: J Alex
authors.initials: JA
authors.lastname: Hammond
authors.forename: Jason H
authors.initials: JH
authors.lastname: Franklin
authors.forename: Iram
authors.initials: I
authors.lastname: Siddiqui
authors.forename: Bret
authors.initials: B
authors.lastname: Wehrli
authors.forename: Keith
authors.initials: K
authors.lastname: Kwan
authors.forename: James
authors.initials: J
authors.lastname: Koropatnick
authors.forename: Joe S
authors.initials: JS
authors.lastname: Mymryk
authors.forename: John W
authors.initials: JW
authors.lastname: Barrett
authors.forename: John
authors.initials: J
authors.lastname: Yoo
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000096:biosynthesis; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D005931:Glottis / Q000378:metabolism* / Q000473:pathology / Q000528:radiation effects; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D007822:Laryngeal Neoplasms / Q000453:epidemiology / Q000378:metabolism / Q000532:radiotherapy*; D008297:Male; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors; D017211:Treatment Failure
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen