Head and neck and skin (HNS) GEC-ESTRO and BRAPHYQS working groups joint critical review of the use of Rhenium-188 in dermato-oncology.

Non-melanoma skin cancers are increasing globally, prompting the need for innovative, non-invasive treatment approaches. Radioactive rhenium (Re) paste has emerged as an open-source radiation-based modality in dermato-oncology, offering a novel alternative to conventional radiotherapy and brachytherapy. In this review, a systematic literature search was conducted using PubMed, Scopus, Web of Science, and Google Scholar for studies published over the past 20 years. Data were extracted from case series, pilot studies, and clinical trials, with particular emphasis on response rates, dosimetric parameters, and treatment-associated toxicity. Findings from approximately 240 patients demonstrated complete response rates ranging from 86 % to 100 % after one or two treatment applications, while dosimetric analyses revealed a rapid dose fall-off that effectively confines the therapeutic effect to a tissue depth of 2-3  mm, with most adverse effects being mild and transient. Notably, Re differs from conventional brachytherapy (specifically high-dose-rate modality) due to its open-source application and unique dosimetric profile. The use of Re in clinical practice mandates a highly specialized, multidisciplinary team, including radiation oncologists, nuclear medicine specialists, and experienced medical physicists, and strict quality assurance protocols, thereby limiting its application to carefully selected cases. Although Re therapy offers a promising alternative for the treatment of superficial skin cancers, its distinct clinical and dosimetric characteristics warrant further randomized studies with extended follow-up to validate its efficacy and refine patient selection criteria under rigorous multidisciplinary oversight.