Enhancement of bleomycin cytotoxicity to tumor cells by pulsed electric fields

Cytotoxicity of anticancer drugs such as bleomycin, to tumor cells can be significantly enhanced by combining it with pulsed electric fields. This new modality of cancer treatment called electrochemotherapy has been very effective for localized tumors with tremendous potential for treatment of internal tumors. The present work deals with ECT experiments on human pancreatic and non-small cell lung cancers grown subcutaneously on the flank of nude mice. Results of pancreatic cancer indicate complete tumor regressions in nearly 88% of the cases 28 days after a single treatment with 6 pulses of 1370 V and 99 /spl mu/s duration. About 64% of these mice showed no palpable tumor for 120 days after treatment, a complete cure by WHO definition. Histopathological studies showed absence of tumor cells in the excisional biopsy of tissue from tumor region. The ultrasonic guidance of acupuncture needles in internal tumors was found feasible indicating treatment possibilities in situ.