Treating a tumor or the like with an electric field

A method for selectively destroying dividing cells in living tissue, the dividing cells having polarizable intracellular members, the method comprising the steps of:

• positioning first and second electrodes in relation to the living tissue, each of the electrodes having a surface configured for placement against the living tissue and a conductor that is electrically insulated from the surface;
• applying an alternating electric potential between the first and second conductors so that the living tissue is subjected to an alternating electric field,
• wherein passage of the electric field through the dividing cells in late anaphase or telophase transforms the electric field into a non-homogeneous electric field that produces an increased density electric field in a region of a cleavage furrow of the dividing cells, and wherein the electric field has amplitude and frequency characteristics such that long-term application of the electric field causes the destruction of cells as they divide, but wherein the electric field is sufficiently small so that during long-term application of the electric field, the destruction of the dividing cells is not caused by heat.

An apparatus for selectively destroying dividing cells that are in a localized area of living tissue, the dividing cells having polarizable intracellular members, the apparatus comprising:

• at least two electrodes, each electrode having an associated conductor and a dielectric material configured for placement against living tissue that insulates the conductor from the living tissue;
• and
• an electric field source for applying an alternating electric potential across the conductors such that a resulting electric field in the dividing cells is transformed into a non-homogenous electric field that produces an increased density electric field in a region of the dividing cells, the non-homogenous electric field being of sufficient intensity to cause the intracellular members to be drawn to the region where the electric field has increased density to cause a pressure increase in this region which causes a structural breakdown of the dividing cells wherein the electric field is sufficiently small such that the structural breakdown of the dividing cells is not caused by heat.