Bleomycin-mediated electrochemotherapy of metastatic melanoma.

BACKGROUND: Electroporation is a new technique that enhances the antitumor effects of chemotherapy by exposing cancerous tissues to pulses of electricity. When used in combination with conventional chemotherapy, the procedure is termed electrochemotherapy (ECT). The electric pulses increase cell membrane permeability and thus intracellular access. Electrochemotherapy has been shown to have potent antitumor activity in a number of in vitro studies, several animal models, and clinical trials with squamous cell carcinomas and basal cell carcinomas. OBJECTIVE: To report the effects of ECT in 5 patients with metastatic malignant melanoma. RESULTS: Twenty-three lesions of metastatic melanoma were treated with intralesional bleomycin sulfate followed by pulses of electricity. Pulses were delivered via caliper or needle electrodes placed around the tumor. Complete responses were observed in 18 tumors (78%) and partial responses were seen in 4 (17%). No responses were seen in lesions treated with either pulses or bleomycin alone. Vital signs were closely monitored during the procedure, and minimal side effects were noted. CONCLUSIONS: This is the first study that documents the antitumor effects of ECT in metastatic melanoma. Although not a cure, it may be an effective alternative to palliative surgery or irradiation in these patients.