Electrochemotherapy with intravenous bleomycin for advanced non-melanoma skin cancers and for cutaneous and subcutaneous metastases from melanoma

Background: The treatment of cutaneous advanced non-melanoma skin cancers (NMSC) and multiple cutaneous and subcutaneous melanoma metastases (Mm) represents a main therapeutic challenge. Electrochemotherapy (ECT) is an anticancer procedure that facilitates the penetration of cytotoxic drugs into cancer cells by means of the application of electrical pulses. The aim of our study was to evaluate efficacy and tolerability of ECT in the treatment of advanced NMSC and Mm. Methods: Thirteen patients with a total of 88 cutaneous and subcutaneous tumour lesions were selected (69 Mm in 6 patients and 19 NMSC in 7 patients). The lesions were divided into "Target" (NMSC: 7; Mm: 9) and "Non-target" (NMSC: 12; Mm: 60) lesions according to RECIST criteria 1.1. All patients underwent ECT under mild general anaesthesia. Eight minutes following intravenous bleomycin, electrical pulses were delivered to the tumour nodules using a square wave pulse generator (CliniporatorTM, IGEA S.p.A., Carpi, Italy). Results: A complete response of "Target" NMSC lesions and "Target" Mm nodules was observed in 85.7% (6/7) and 33.3% (3/9), respectively. Only one NMSC underwent two courses of treatment, achieving a complete response 1 month after the second ECT session. Among Mm, 6 of 9 "Target" lesions received more than one ECT session, achieving a size reduction in 3 of 6 lesions. This improvement, however, was not classified as partial response because the size reduction was lower than 30%. In 1 patient, one Mm "Target" lesion increased in volume while other two "Target" lesions appeared stable. No statistically significant difference was observed, between the size of the lesions before treatment and after treatment, nevertheless statistical significance was achieved in the "Target" lesions comparing the response to ECT of NMSC group vs. Mm group (P<0.05). Conclusions: Our study confirms the potential therapeutic role of ECT. This procedure could represent the 1st line treatment for advanced NMSC, especially in elderly patients not suitable for surgery or radiotherapy. As already described in literature, we hereby validate the effective role of ECT in the palliation of Mm.