title: Deep inspiration breath-hold (DIBH) radiotherapy in left-sided breast cancer: Dosimetrical comparison and clinical feasibility in 20 patients.
abstract: BACKGROUND
  Adjuvant radiotherapy after breast-conserving surgery (BCS) for breast cancer (BC) is a well-established indication. The risk of ischaemic heart disease after radiotherapy for BC increases linearly with the heart mean dose with no apparent threshold. Radiotherapy to the left breast in deep inspiration breath-hold (DIBH) reduces the dose to the heart. A new linac system with an integrated surface scanner (SS) for DIBH treatments was recently installed in our department. We tested it for potential benefits, safety, patients' acceptance/compliance and associated additional workload.
  
  
  METHODS
  Twenty consecutive patients following BCS for breast carcinoma of the left side were enrolled in our institutional DIBH protocol. We compared dose to the heart and ipsilateral lung (IL) between plans in DIBH and free breathing (FB) using standard defined parameters: mean dose, maximal dose to a volume of 2 cm(3) (D2 cm (3)), volume receiving ≥ 5 Gy (V5), 10 Gy (V10), 15 Gy (V15) and 20 Gy (V20). Comparison of median calculated dose values was performed using a two-tailed Wilcoxon signed rank test.
  
  
  RESULTS
  DIBH was associated with a statistically significant reduction (p < 0.001) in all studied parameters for the heart and the IL. In 16 of 20 patients the heart D2 cm (3) was less than 42 Gy in DIBH. In FB the heart D2 cm (3) was ≥ 42 Gy in 17 of 20 patients. The median daily treatment time was 9 min.
  
  
  CONCLUSIONS
  Radiotherapy of the left breast in DIBH using a SS could easily be incorporated into daily routine and is associated with significant dose reduction to the heart and IL.
authors.affiliation: Klinik für Strahlentherapie und Radioonkologie, Evangelische Kliniken Gelsenkirchen, Munckelstraße 27, 45879, Gelsenkirchen, Deutschland, heppdelosrios@evk-ge.de.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Hepp
authors.forename: Mark
authors.initials: M
authors.lastname: Ammerpohl
authors.forename: Christina
authors.initials: C
authors.lastname: Morgenstern
authors.forename: Lisa
authors.initials: L
authors.lastname: Nielinger
authors.forename: Patricia
authors.initials: P
authors.lastname: Erichsen
authors.forename: Abdallah
authors.initials: A
authors.lastname: Abdallah
authors.forename: Razvan
authors.initials: R
authors.lastname: Galalae
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000532:radiotherapy*; D062485:Breath Holding; D005240:Feasibility Studies; D005260:Female; D006321:Heart / Q000528:radiation effects*; D006801:Humans; D001239:Inhalation; D008875:Middle Aged; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry; D016896:Treatment Outcome