title: Examining tumor control and toxicity after stereotactic body radiotherapy in locally recurrent previously irradiated head and neck cancers: implications of treatment duration and tumor volume.
abstract: BACKGROUND
  Stereotactic body radiotherapy (SBRT) has been studied in locally recurrent previously-irradiated head and neck cancers; however, the optimum fractionation and patient selection continues to be defined.
  
  
  METHODS
  Patients (n = 132) with locally recurrent head and neck cancer salvaged via SBRT ± cetuximab (median, 44 Gy/5 fractions) from November 2004 to May 2011 were retrospectively reviewed. Disease outcomes and toxicity were analyzed by predictive factors including treatment duration and tumor volume.
  
  
  RESULTS
  At a median 6-month follow-up (range, 0-55 months), treatment duration <14 days was associated with significantly improved recurrence-free survival (RFS) at the expense of increased late toxicity (p = .029). Tumor volume >25 cc remained a significant predictor of inferior survival and tumor control, and was associated with significantly more acute toxicity (p = .017) but no difference in late toxicity.
  
  
  CONCLUSIONS
  SBRT ± cetuximab achieves promising tumor control and survival with low rates of acute/late toxicity even for recurrences >25 cc. Prolongations in treatment time may decrease late toxicity at the expense of disease control.
authors.affiliation: Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania.
authors.forename: John A
authors.initials: JA
authors.lastname: Vargo
authors.forename: Dwight E
authors.initials: DE
authors.lastname: Heron
authors.forename: Robert L
authors.initials: RL
authors.lastname: Ferris
authors.forename: Jean-Claude M
authors.initials: JC
authors.lastname: Rwigema
authors.forename: Ronny
authors.initials: R
authors.lastname: Kalash
authors.forename: Rodeny E
authors.initials: RE
authors.lastname: Wegner
authors.forename: James
authors.initials: J
authors.lastname: Ohr
authors.forename: Steven
authors.initials: S
authors.lastname: Burton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use; D000068818:Cetuximab; D005260:Female; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D018579:Patient Selection; D016634:Radiosurgery; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068818:Cetuximab
keywords: cetuximab; reirradiation head and neck; stereotactic body radiation therapy (SBRT); treatment time; tumor volume