Advancing patient setup: A comprehensive scoping review of tattoo-less techniques in radiation therapy

In recent years, alternative methods to dark ink tattoos for patient positioning in radiotherapy have been explored. This review aims to analyse the evidence for alternative strategies to traditional dark tattoos. An electronic search was conducted in PubMed, EMBASE, Cochrane Library, Web of Sciences and SCOPUS. Twenty-one articles out of 383 titles fulfilled the selection criteria and were included in the review. These studies were categorized into tattoo-less methods (n=14), UV ink tattoos (n=4) and other techniques (n=3). In most of the selected articles (n=13) focusing on tattoo-less treatments, SGRT is used for patient positioning. These three alternative techniques to dark tattoos are used in different anatomical regions and treatment modalities, with breast cancer being the most prevalent. Tattoo-less techniques are a promising alternative to traditional tattoo- based methods for patient positioning. They have the potential to improve the patient experience and represent an area of ongoing innovation and improvement.