Electrochemotherapy with intravenous bleomycin for patients with cutaneous malignancies, across tumour histology: a systematic review

Abstract

Background Electrochemotherapy (ECT) is an established treatment for primary and secondary cutaneous tumours. The method combines chemotherapy with electroporation, thus increasing the cytotoxic effect of the chemotherapeutic drug. Bleomycin is the drug of choice for ECT, as it is already well established as a treatment for several cancer types and has the largest increase in efficacy after electroporation, enhancing the cytotoxic effect several hundred fold. The response rates of ECT have over the past 30 years been high and consistent. Case based reports point out that the efficacy possibly can be maintained even when the dose of bleomycin is reduced. Consequently in 2018, studies began investigating reducing the bleomycin dose. Aim The purpose of this review is to summarise all data published using intravenous bleomycin for cutaneous malignancies and is to our knowledge the first review to examine the use of a reduced bleomycin dose in ECT. Methods This study is a systematic review. Fifty-five clinical studies investigating ECT with intravenous bleomycin for patients with cutaneous malignancies were included. Results Studies published from 1993 to 2021 investigating the effect of ECT include 3729 patients and indicate a consistent and high response with a mean objective response rate (ORR) of 81.5%. Interestingly, studies using lower doses of bleomycin observe a similar ORR (85.5%), opening the possibility that a lower dose may not be inferior. Conclusion This study gives an overview of published studies on ECT with intravenous bleomycin for patients with cutaneous malignancies, including the use of a reduced bleomycin dose, as preparation for a randomised study.