Electrochemically Induced Hepatic Necrosis: The Next Step Forward in Patients With Unresectable Liver Tumours?

Abstract

Background: The treatment of patients with unresectable liver tumours remains an unsolved clinical problem. Several methods of locoregional treatment have been developed. These methods rely mainly on direct thermal or chemical insults and consequently have their own inherent limitations in clinical usage. The 'ideal' treatment would combine the direct cytotoxic effects of chemical treatments with the relative predictability of thermal insults, without the associated complications. This study aims to investigate whether the direct chemical effect of electrolytic hepatic necrosis is associated with any heating effect, and if so, whether the temperature change is dose-dependent. Methods: An electrolytic 'dose' sufficient to induce a localized zone of hepatic necrosis was delivered to the livers of rats and pigs via implanted platinum electrodes. Results: The results showed that there was no significant temperature increase at low current levels (2-4 mA) in the rat liver. In the pig, there was a significant ( P < 0.01) increase in temperature of 4 . 2 T during electrolysis, when delivered at between 20 and 50 mA.However, such a small increase in temperature would have been insufficient to cause appreciable thermal necrosis. Conclusions: This study demonstrates that electrolysis-induced hepatic necrosis is produced without an increase in temperature; clearly cell death results from the direct effects of cytotoxic electrode products and an alteration of intracellular pH. Consequently, it is likely that as a method for ablating liver tumours, electrolysis should be associated with fewer complications than other forms of locoregional treatment.

Modelling the interactions between tumour cells and a blood vessel in a microenvironment within a vascular tumour

“…The rate of such necrosis is assumed to be proportional to the local density of live cells and to be induced only when the oxygen tension drops below a threshold value. Other forms of necrotic cell death occur at all oxygen tensions, for example, necrosis due to low pH [4]: we stress that we do not consider such mechanisms in this paper. When live cells die by apoptosis, they become inactive but retain their form until they are either degraded by enzymes in the matrix or phagocytosed by macrophages (a type of stromal cell that moves around the tumour and accumulates in hypoxic areas) [19].…”

Endoscopic Perductal Electrolytic Ablation of the Pancreas: Experimental Studies of Morbidity and Mortality

“…Electrolysis may be particularly suitable for pancreatic ablation because of its relatively slow, nonthermal action. Passage of a small direct current between platinum electrodes results in local tissue pH change and also the release of cytotoxic free radicals and gases [20] , leading to an area of tissue necrosis. Another advantage of electrolysis over other locally ablative techniques is the demonstrable safety of electrolytic ablation in the vicinity of large vessels.…”

Thermal ablation for unresectable liver tumours, time to move forward?

“…Electrolytic abla tion, also known as lowlevel direct current therapy, is an al ternative method which produces no change in temperature and exerts its effects through electrochemical and pH modi fications and the production of free radicals. These changes render the microenvironment close to the probe extremely cytotoxic, produce tissue necrosis and are not influenced to any large degree by the presence of blood vessels or bile ducts [39,40] . Due to the almost complete absence of thermal energy developed, the procedure has proved particularly safe in experimental studies where ablations were conduct ed close or even within major vessels (Figure 1) [4143] .…”