Electrochemical treatment of tumours.

The electrochemical treatment (EChT) of tumours implies that tumour tissue is treated with a continuous direct current through two or more electrodes placed in or near the tumour. The treatment offers considerable promise of a safe, simple and relatively noninvasive anti-tumour therapy for treatment of localised malignant as well as benign tumours. Although more than 10,000 patients have been treated in China during the past 10 years, EChT has not yet been universally accepted. The reason for this is the lack of essential preclinical studies and controlled clinical trials. Uncertainties regarding the destruction mechanism of EChT also hinder the development of an optimised and reliable dose-planning methodology. This article reviews the collected Chinese and occidental experiences of the electrochemical treatment of tumours, alone and in combination with other therapies. The current knowledge of the destruction mechanism underlying EChT is presented along with different approaches towards a dose planning methodology. In addition, we discuss our view of different important parameters that have to be accounted for, if clinical trials are to be initiated outside of China.

Electrochemical aspects of treatment of tissue with direct current.

In the electrochemical treatment of tissue with direct current the main reactions at the anode are the formation of oxygen in addition to acidification due to liberated hydrogen ions, and formation of chloride, if platinum is used as anode material. At the cathode hydrogen is formed and hydroxide ions are liberated. Calculations have been made for the two major anodic reactions. As a first approximation just one-dimensional diffusion is considered corresponding to the use of plate electrodes. It appears from these calculations that the liberated hydrogen ions determine the extension of the locally destroyed zone around the anode. The destructive effect of chlorine probably occurs in an inner zone close to the anode.