title: A randomized control trial evaluating fluorescent ink versus dark ink tattoos for breast radiotherapy.
abstract: OBJECTIVE
  The purpose of this UK study was to evaluate interfraction reproducibility and body image score when using ultraviolet (UV) tattoos (not visible in ambient lighting) for external references during breast/chest wall radiotherapy and compare with conventional dark ink.
  
  
  METHODS
  In this non-blinded, single-centre, parallel group, randomized control trial, patients were allocated to receive either conventional dark ink or UV ink tattoos using computer-generated random blocks. Participant assignment was not masked. Systematic (∑) and random (σ) setup errors were determined using electronic portal images. Body image questionnaires were completed at pre-treatment, 1 month and 6 months to determine the impact of tattoo type on body image. The primary end point was to determine that UV tattoo random error (σsetup) was no less accurate than with conventional dark ink tattoos, i.e. <2.8 mm.
  
  
  RESULTS
  46 patients were randomized to receive conventional dark or UV ink tattoos. 45 patients completed treatment (UV: n = 23, dark: n = 22). σsetupfor the UV tattoo group was <2.8 mm in the u and v directions (p = 0.001 and p = 0.009, respectively). A larger proportion of patients reported improvement in body image score in the UV tattoo group compared with the dark ink group at 1 month [56% (13/23) vs 14% (3/22), respectively] and 6 months [52% (11/21) vs 38% (8/21), respectively].
  
  
  CONCLUSIONS
  UV tattoos were associated with interfraction setup reproducibility comparable with conventional dark ink. Patients reported a more favourable change in body image score up to 6 months following treatment. Advances in knowledge: This study is the first to evaluate UV tattoo external references in a randomized control trial.
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Landeg
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.|2 Institute of Cancer Research (ICR), London, UK.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Kirby
authors.affiliation: 3 Department of Chemistry, University of Cambridge, Cambridge, UK.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Lee
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.|2 Institute of Cancer Research (ICR), London, UK.|5 Southampton Oncology Centre, Southampton University Hospitals, Southampton, UK.
authors.forename: Freddie
authors.initials: F
authors.lastname: Bartlett
authors.affiliation: 4 Kingston University, London, UK.
authors.forename: Kumud
authors.initials: K
authors.lastname: Titmarsh
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.
authors.forename: Ellen
authors.initials: E
authors.lastname: Donovan
authors.affiliation: 2 Institute of Cancer Research (ICR), London, UK.
authors.forename: Clare L
authors.initials: CL
authors.lastname: Griffin
authors.affiliation: 2 Institute of Cancer Research (ICR), London, UK.
authors.forename: Lone
authors.initials: L
authors.lastname: Gothard
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.
authors.forename: Imogen
authors.initials: I
authors.lastname: Locke
authors.affiliation: 1 The Royal Marsden NHS Foundation Trust, London, UK.|2 Institute of Cancer Research (ICR), London, UK.
authors.forename: Helen A
authors.initials: HA
authors.lastname: McNair
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D005260:Female; D005453:Fluorescence; D006801:Humans; D007281:Ink; D008875:Middle Aged; D015203:Reproducibility of Results; D013653:Tattooing / Q000379:methods*; D006113:United Kingdom