title: [Partial delegation to radiation therapists of the control by cone beam CT of prostate positioning].
abstract: OBJECTIVE
  Intensity modulated radiotherapy for prostate cancer involves daily monitoring of the positioning of the prostate, possible with cone beam CT (CBCT). It allows increased accuracy compared to readjustments but induces an increase in the time dedicated to these medical checks. The aim of the study was to evaluate the possibility of delegation of this task to the radiation therapists by comparing their readjustments to the doctors.
  
  
  METHODS
  Five consecutive patients treated with radiation for prostate cancer (76Gy) were analysed. All had a daily CBCT for position control. The movements of the prostate relative to the bony part, the positional variations of the prostate measured by the radiation therapists and the doctors and medical time required to analyse imagery (filling of the rectum and bladder and perform a recalibration) were measured.
  
  
  RESULTS
  One hundred seventy-six CBCT were analysed or 980 steps in the three axes. The movements of the prostate relative to bony part were respectively at least 5mm in 19%, 7% and 3% in the anterior-posterior, upper-lower and right-left axes. Changes readjustments between radiation therapists and doctors were in 95% of cases at the most 4mm in the anterior-posterior and upper-lower axis, and 3mm in the left-right axis. The time for medical use of the CBCT averaged 8min 40 [4 to 22min].
  
  
  CONCLUSIONS
  The daily readjustment on the prostate using CBCT may be delegated to radiation therapists with acceptable concordance of less than 4mm for 95% of measurements. An initial and ongoing training will ensure treatment safety.
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: C
authors.initials: C
authors.lastname: Benhaïm
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: G
authors.initials: G
authors.lastname: Loos
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: J L
authors.initials: JL
authors.lastname: Achard
authors.affiliation: Département de physique médicale, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: L
authors.initials: L
authors.lastname: Berger
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: C
authors.initials: C
authors.lastname: Caillé
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: T
authors.initials: T
authors.lastname: Frédéric-Moreau
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France.
authors.forename: J
authors.initials: J
authors.lastname: Biau
authors.affiliation: Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 392, 63011 Clermont-Ferrand cedex 1, France. Electronic address: michel.lapeyre@clermont.unicancer.fr.
authors.forename: M
authors.initials: M
authors.lastname: Lapeyre
mesh_terms: D000368:Aged; D000488:Allied Health Personnel; D054893:Cone-Beam Computed Tomography; D004526:Efficiency; D006801:Humans; D008297:Male; D008875:Middle Aged; D058958:Organs at Risk; D056888:Patient Positioning; D010819:Physician's Role; D011467:Prostate / Q000000981:diagnostic imaging*; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D013997:Time Factors
keywords: Cancer de prostate; Cone beam CT; Delegation; Délégation; IGRT; Prostate cancer; Tomographie conique