title: Recalculation of dose for each fraction of treatment on TomoTherapy.
abstract: OBJECTIVE
  The VoxTox study, linking delivered dose to toxicity requires recalculation of typically 20-37 fractions per patient, for nearly 2000 patients. This requires a non-interactive interface permitting batch calculation with multiple computers.
  
  
  METHODS
  Data are extracted from the TomoTherapy(®) archive and processed using the computational task-management system GANGA. Doses are calculated for each fraction of radiotherapy using the daily megavoltage (MV) CT images. The calculated dose cube is saved as a digital imaging and communications in medicine RTDOSE object, which can then be read by utilities that calculate dose-volume histograms or dose surface maps. The rectum is delineated on daily MV images using an implementation of the Chan-Vese algorithm.
  
  
  RESULTS
  On a cluster of up to 117 central processing units, dose cubes for all fractions of 151 patients took 12 days to calculate. Outlining the rectum on all slices and fractions on 151 patients took 7 h. We also present results of the Hounsfield unit (HU) calibration of TomoTherapy MV images, measured over an 8-year period, showing that the HU calibration has become less variable over time, with no large changes observed after 2011.
  
  
  CONCLUSIONS
  We have developed a system for automatic dose recalculation of TomoTherapy dose distributions. This does not tie up the clinically needed planning system but can be run on a cluster of independent machines, enabling recalculation of delivered dose without user intervention.
  
  
  CONCLUSIONS
  The use of a task management system for automation of dose calculation and outlining enables work to be scaled up to the level required for large studies.
authors.affiliation: 1 Cambridge University Hospitals NHS Foundation Trust, Department of Medical Physics and Clinical Engineering, Addenbrooke's Hospital, Cambridge, UK.|2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Thomas
authors.affiliation: 1 Cambridge University Hospitals NHS Foundation Trust, Department of Medical Physics and Clinical Engineering, Addenbrooke's Hospital, Cambridge, UK.|2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Marina
authors.initials: M
authors.lastname: Romanchikova
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|3 Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK.
authors.forename: Karl
authors.initials: K
authors.lastname: Harrison
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|3 Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Parker
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|4 Department of Oncology, Cambridge University Hospitals NHS Foundation Trust, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Bates
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|5 Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Scaife
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|6 Department of Engineering, University of Cambridge, Cambridge, UK.
authors.forename: Michael P F
authors.initials: MP
authors.lastname: Sutcliffe
authors.affiliation: 2 Cancer Research UK VoxTox Research Group, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.|5 Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Addenbrooke's Hospital, Cambridge, UK.
authors.forename: Neil G
authors.initials: NG
authors.lastname: Burnet
mesh_terms: D002138:Calibration; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D012007:Rectum / Q000000981:diagnostic imaging / Q000528:radiation effects; D014057:Tomography, X-Ray Computed