Background: Electrochemotherapy (ECT) is performed by locally administering a chemotherapeutic agent in combination with electric pulses. Previous clinical studies have demonstrated the effectiveness of ECT. In these initial trials, the drug was administered intravenously, followed by administration of electric pulses directly to the tumor. This study was initiated to determine whether an intralesional injection of the drug in combination with electric pulses could provide an improved result. A group of 34 patients was studied.
Methods: The dose of intralesional bleomycin was based on tumor volume. This was followed 10 minutes later by 6 or 8 99-microsec pulses of electricity at an amplitude of 1.3 kV/cm. Both the bleomycin and the electric pulses were administered after 1% lidocaine with epinephrine solution was injected around the treatment site.
Results: All patients responded to the treatment. Responses were observed in 142 (99%) of 143 metastatic nodules or primary tumors within 12 weeks, with complete responses observed in 130 (91%) of the nodules. No complete responses were observed in nodules treated with bleomycin only or electric pulses only. Random biopsies confirmed the clinical findings. All patients tolerated the procedure well, and no significant side effects were noted. Muscle contraction was evident during administration of each electric pulse but promptly subsided after the pulse.
Conclusions: ECT was shown to be an effective local treatment for cutaneous malignancies. The results suggest that ECT may have a tissue-sparing effect and result in minimal scarring. ECT may be a suitable alternative therapy for the treatment of basal cell carcinoma, local or regional recurrent melanoma, and other skin cancers.