Breast Radiotherapy: Invisible Tattoos for External References
Conventional dark-ink tattoos used for external references during breast radiotherapy can negatively impact patients' long-term cosmetic outcomes, serve as a reminder of diagnosis and treatment1,2 and be incorrectly identified in patients with dark-skin tone3. Fluorescent tattoos offer an innovative solution to overcome these limitations but have not been clinically tested. This single-centre study evaluated the efficacy of using fluorescent tattoos visualised with an ultraviolet (UV) torch together with the impact on patient experience in patients receiving breast radiotherapy.
Prior to recruitment extensive pilot work was performed to assess visibility of fluorescent inks with a selection of UV torches. Patients receiving adjuvant radiotherapy for breast cancer were randomised to receive either fluorescent or conventional dark-ink tattoos. Tattoos were administered bilaterally and medially. Measurements and photographs were taken during CT planning to record tattoo location. Treatment times were recorded and radiographer satisfaction questionnaires used to determine acceptability. The primary endpoint of interfraction reproducibility (mean set-up error) of patient position was determined using electronic portal images. Patient questionnaires were completed at baseline (pre-treatment), 1 month and 6 months post-radiotherapy to determine the impact of tattoo type on body-image.
Pilot work demonstrated that optimum torch and fluorescent ink selection was paramount for safe and effective clinical application. 23/ 26 patients approached have so far consented. No adverse effects have been reported to date, fluorescent tattoos were visible in 23/23 patients. No gross errors in setup were identified. Random and systematic errors for the whole cohort (n=42) will be presented.
The use of fluorescent tattoos with optimum UV torches is an innovative alternative to dark-ink tattoos. If shown to be successful in this patient cohort, the technique will be assessed in other tumour sites and in situations where black ink is not appropriate.
We acknowledge NHS funding to the NIHR Biomedical Research Centre.
This work was supported by the Institute of Cancer Research (ICR), and Cancer Research UK [CUK] grant number C46/A3970 to the ICR Section of Radiotherapy.
1. Bregnhøj, A., Hædersdal, M.(2010) 'Q-switched YAG laser vs. punch biopsy excision for iatrogenic radiation tattoo markers - a randomized controlled trial' ,Journal of the European Academy of Dermatology and Venereology, 24(10), p.1183-1186.
2. David, E.J., Castle, S.K.B., Mossi, K.M. (2006) 'Localization Tattoos: An Alternative Method Using Fluorescent Inks', Radiation Therapist, 15(1), p.1-5.
3. Smolenski, M.C. (2008) Tattooing method for radiation therapy, Available at: http://www.google.pl/patents/WO2008074052A1?cl=en. [Accessed 10/11/2013]