title: Quantification of the effect of treatment duration on local-regional failure after definitive concurrent chemotherapy and intensity-modulated radiation therapy for squamous cell carcinoma of the head and neck.
abstract: BACKGROUND
  The purpose of this study was to quantify the effect of treatment duration on locoregional progression after definitive concurrent chemoradiation (CCRT) for squamous cell carcinoma of the head and neck (SCCHN).
  
  
  METHODS
  We conducted a retrospective chart review of patients treated between 2004 and 2010. After a prior analysis, measures were taken to limit therapy beyond 7 weeks. Comparison of outcomes were made between cohorts 1 (2004-2007, n = 78) and 2 (2007-2010, n = 62).
  
  
  RESULTS
  Median therapy duration was statistically significantly different between cohorts as follows: 51 days, cohort 1 and 46 days, cohort 2 (p < .01). Locoregional progression in cohorts 1 and 2 was 19% and 5% (p = .01), respectively. On multivariate analysis, patients with prolonged treatment (≥57 days) had an 8-fold increase in risk of locoregional progression compared to patients who completed on time (p < .01).
  
  
  CONCLUSIONS
  Treatment duration was a significant predictor of locoregional progression in patients with SCCHN who received definitive CCRT.
authors.affiliation: Division of Cancer Prevention and Population Sciences, Roswell Park Cancer Institute, Buffalo, New York 14263, USA. mary.platek@roswellpark.org
authors.forename: Mary E
authors.initials: ME
authors.lastname: Platek
authors.forename: Susan A
authors.initials: SA
authors.lastname: McCloskey
authors.forename: Myra
authors.initials: M
authors.lastname: Cruz
authors.forename: Mark S
authors.initials: MS
authors.lastname: Burke
authors.forename: Mary E
authors.initials: ME
authors.lastname: Reid
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Wilding
authors.forename: Nestor R
authors.initials: NR
authors.lastname: Rigual
authors.forename: Saurin R
authors.initials: SR
authors.lastname: Popat
authors.forename: Thom R
authors.initials: TR
authors.lastname: Loree
authors.forename: Vishal
authors.initials: V
authors.lastname: Gupta
authors.forename: Graham W
authors.initials: GW
authors.lastname: Warren
authors.forename: Maureen
authors.initials: M
authors.lastname: Sullivan
authors.forename: Wesley L
authors.initials: WL
authors.lastname: Hicks
authors.forename: Anurag K
authors.initials: AK
authors.lastname: Singh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000628:therapy*; D059248:Chemoradiotherapy; D018450:Disease Progression; D005260:Female; D006258:Head and Neck Neoplasms / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck; D013997:Time Factors; D017211:Treatment Failure