title: A voluntary breath-hold treatment technique for the left breast with unfavorable cardiac anatomy using surface imaging.
abstract: OBJECTIVE
  Breath-hold (BH) treatments can be used to reduce cardiac dose for patients with left-sided breast cancer and unfavorable cardiac anatomy. A surface imaging technique was developed for accurate patient setup and reproducible real-time BH positioning.
  
  
  METHODS
  Three-dimensional surface images were obtained for 20 patients. Surface imaging was used to correct the daily setup for each patient. Initial setup data were recorded for 443 fractions and were analyzed to assess random and systematic errors. Real time monitoring was used to verify surface placement during BH. The radiation beam was not turned on if the BH position difference was greater than 5 mm. Real-time surface data were analyzed for 2398 BHs and 363 treatment fractions. The mean and maximum differences were calculated. The percentage of BHs greater than tolerance was calculated.
  
  
  RESULTS
  The mean shifts for initial patient setup were 2.0 mm, 1.2 mm, and 0.3 mm in the vertical, longitudinal, and lateral directions, respectively. The mean 3-dimensional vector shift was 7.8 mm. Random and systematic errors were less than 4 mm. Real-time surface monitoring data indicated that 22% of the BHs were outside the 5-mm tolerance (range, 7%-41%), and there was a correlation with breast volume. The mean difference between the treated and reference BH positions was 2 mm in each direction. For out-of-tolerance BHs, the average difference in the BH position was 6.3 mm, and the average maximum difference was 8.8 mm.
  
  
  CONCLUSIONS
  Daily real-time surface imaging ensures accurate and reproducible positioning for BH treatment of left-sided breast cancer patients with unfavorable cardiac anatomy.
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts, USA. dgierga@partners.org
authors.forename: David P
authors.initials: DP
authors.lastname: Gierga
authors.forename: Julie C
authors.initials: JC
authors.lastname: Turcotte
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Sharp
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Sedlacek
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Cotter
authors.forename: Alphonse G
authors.initials: AG
authors.lastname: Taghian
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000033:anatomy & histology; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D062485:Breath Holding; D019583:Dose Fractionation, Radiation; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000528:radiation effects*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008875:Middle Aged; D009929:Organ Size; D058958:Organs at Risk / Q000000981:diagnostic imaging / Q000528:radiation effects*; D056888:Patient Positioning / Q000379:methods; D011832:Radiation Injuries / Q000517:prevention & control*; D011859:Radiography; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D061106:Radiotherapy Setup Errors / Q000517:prevention & control*; D011881:Radiotherapy, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D016683:Supine Position; D057188:Workflow