title: Radiation dose uncertainty and correction for a mouse orthotopic and xenograft irradiation model.
abstract: OBJECTIVE
  In animal irradiation models, reported dose can vary significantly from the actual doses delivered. We describe an effective method for in vivo dose verification.
  
  
  METHODS
  Mice bearing commercially-available cell line or patient-derived tumor cell orthotopic or flank xenografts were irradiated using a 160 kVp, 25 mA X-ray source. Entrance dose was evaluated using optically-stimulated luminescence dosimeters (OSLD) and exit dose was assessed using radiochromic film dosimetry.
  
  
  RESULTS
  Tumor position within the irradiation field was validated using external fiducial markers. The average entrance dose in orthotopic tumors from 10 OSLDs placed on two different animal irradiation days was 514 ± 37 cGy (range: 437-545). Exit dose measurements taken from seven radiochromic films on two separate days were 341 ± 21 cGy (a 34% attenuation). Flank tumor irradiation doses measured by OSLD were 368 ± 9 cGy compared to exit doses of 330 cGy measured by radiochromic film.
  
  
  CONCLUSIONS
  Variations related to the irradiation model can lead to significant under or overdosing in vivo which can affect tumor control and/or biologic endpoints that are dose-dependent. We recommend that dose measurements be determined empirically based on the mouse model and irradiator used and dose compensation adjustments performed to ensure correct and appropriate doses.
authors.affiliation: a Division of Radiation Oncology, Internal Medicine , University of New Mexico School of Medicine , Albuquerque , NM , USA ;|b Department of Radiation Oncology , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: Gregory N
authors.initials: GN
authors.lastname: Gan
authors.affiliation: b Department of Radiation Oncology , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: Cem
authors.initials: C
authors.lastname: Altunbas
authors.affiliation: c Division of Medical Oncology, Department of Medicine , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: John J
authors.initials: JJ
authors.lastname: Morton
authors.affiliation: c Division of Medical Oncology, Department of Medicine , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: Justin
authors.initials: J
authors.lastname: Eagles
authors.affiliation: b Department of Radiation Oncology , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: Jennifer
authors.initials: J
authors.lastname: Backus
authors.affiliation: b Department of Radiation Oncology , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: Wayne
authors.initials: W
authors.lastname: Dzingle
authors.affiliation: b Department of Radiation Oncology , University of Colorado School of Medicine , Aurora , CO , USA ;
authors.forename: David
authors.initials: D
authors.lastname: Raben
authors.affiliation: c Division of Medical Oncology, Department of Medicine , University of Colorado School of Medicine , Aurora , CO , USA ;|d Charles C. Gates Center for Stem Cell Biology, University of Colorado School of Medicine , Aurora , CO , USA ;|e Department of Otolaryngology , University of Colorado School of Medicine , Aurora , CO , USA.
authors.forename: Antonio
authors.initials: A
authors.lastname: Jimeno
mesh_terms: D065638:Absorption, Radiation; D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D051379:Mice; D008819:Mice, Nude; D008954:Models, Biological; D015233:Models, Statistical; D009374:Neoplasms, Experimental / Q000532:radiotherapy*; D011874:Radiometry / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000295:instrumentation / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Radiation dosimetry; mouse tumor xenografting; radiophysics