Hat for treating a tumor or the like

A hat for treatment of an intra-cranial tumor or lesion by selectively destroying dividing cells of the tumor, the dividing cells having polarizable or polar or charged intracellular members, the hat comprising:

• a hat body to be worn over a head and including a predetermined number of openings formed therein;
• at least one insulated electrode unit for placement in one of the openings of the hat, each unit being a member having an insulated electrode disposed at one face thereof and a biasing mechanism for applying a biasing force against the insulated electrode in a direction away from the hat body, the insulated electrode being disposed at one face of the hat body when the unit is inserted and securely held within the opening;
• and an electric field source for applying an alternating electric potential across at least two insulated electrodes to create an electric field in the dividing cells, wherein passage of the electric field through the dividing cells in late anaphase or telophase transforms the electric field into a non-homogenous electric field that produces an increased density electric field in a region of a cleavage furrow of the dividing cells, wherein the non-homogeneous electric field produced within the dividing cells 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.