title: Better compliance with hypofractionation vs. conventional fractionation in adjuvant breast cancer radiotherapy : Results of a single, institutional, retrospective study.
abstract: BACKGROUND
  The aim of the study was to identify factors significantly associated with the occurrence of unintended treatment interruptions in adjuvant breast cancer radiotherapy.
  
  
  METHODS
  Patients treated with postoperative radiotherapy of the breast or chest wall between March 2014 and August 2016 were evaluated. The radiotherapy regimens and techniques applied were either conventional fractionation (CF; 28 daily fractions of 1.8 Gy or 25 fractions of 2.0 Gy) or hypofractionation (HF; 15 daily fractions of 2.67 Gy) with inverse planned intensity-modulated radiotherapy (IMRT) or three-dimensional planned conformal radiotherapy (3DCRT). Logistic regression analysis was used to identify factors associated with noncompliance. Noncompliance was defined as the missing of at least one scheduled radiotherapy fraction.
  
  
  RESULTS
  In all, 19 of 140 (13.6%) patients treated with HF and 39 of 146 (26.7%) treated with CF experienced treatment interruptions. Of 23 factors tested, the fractionation regimen emerged as the only independent significant prognostic factor for noncompliance on multivariate analysis (CF; p = 0.007; odds ratio, 2.3; 95% confidence interval, 1.3-4.2). No statistically significant differences concerning the reasons for treatment interruptions could be detected between patients treated with CF or HF.
  
  
  CONCLUSIONS
  HF is significantly associated with a better patient compliance with the prescribed radiotherapy schedule compared with CF. The data suggest that this finding is basically related to the shorter overall treatment time of HF.
authors.affiliation: Department of Radiation Oncology, Saad Specialist Hospital, 31952, Al Khobar, Saudi Arabia. vrudat@saadmedical.com.
authors.forename: Volker
authors.initials: V
authors.lastname: Rudat
authors.affiliation: Department of Radiation Oncology, Saad Specialist Hospital, 31952, Al Khobar, Saudi Arabia.
authors.forename: Alaa
authors.initials: A
authors.lastname: Nour
authors.affiliation: Department of Radiation Oncology, Saad Specialist Hospital, 31952, Al Khobar, Saudi Arabia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hammoud
authors.affiliation: Department of Radiation Oncology, Saad Specialist Hospital, 31952, Al Khobar, Saudi Arabia.
authors.forename: Salam
authors.initials: S
authors.lastname: Abou Ghaida
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data*; D015995:Prevalence; D000069473:Radiation Dose Hypofractionation; D018714:Radiotherapy, Adjuvant / Q000379:methods / Q000706:statistics & numerical data; D020266:Radiotherapy, Conformal; D012189:Retrospective Studies; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology; D016896:Treatment Outcome
keywords: Breast neoplasms; Dose hypofractionation; Radiation injuries; Radiotherapy; Risk factors