A method is disclosed for disrupting capillary blood flow and trapping materials such as chemotherapeutic agents in undesirable tissue, including cells of a cancerous or non-cancerous tumor. The method involves the placement of electrodes into or near the vicinity of capillary vessels supplying blood to capillaries in the undesirable tissue, and application of electrical pulses causing capillary blood flow disruption. In some cases, the electric pulses irreversibly permeate the cell membranes, thereby invoking cell death. The irreversibly permeabilized cells are left in situ and are removed by the bodys immune system. The process may further comprise monitoring blood flow and/or infusion of a material such as a chemotherapeutic agent or marker into the blood.