Proc. ESA Annual Meeting on Electrostatics 2011 1 Tumor Electric Field Distribution Studies using Various Electrode Configurations Poornima Agoramurthy, Luca Campana* and Raji Sundararajan Purdue University, West Lafayette, IN, USA * University of Padova Medical School, Padova, Italy e-mail: pagoramu@purdue.edu, raji@purdue.edu Abstract—Electrochemotherapy, the process of applying electric pulses to facilitate drug transport into cells, is an emerging method in molecular medicine and a promising technique for cancer treatment. Pulse parameters and electrode geometry are dominant factors in this process. The goal of this paper is to demonstrate effects of various electrode configurations and pulse characteristics on the homogeneity of electric field distribution of tumor tissues and develop the best suited electrode model for the treatment of large tumors. Maxwell V13, soft- ware by Ansoft Corporation is used for 2-dimensional and 3-dimensional modeling of tissues and electrodes. External parallel plate electrodes and internal needle electrodes are compared and analyzed. A multi-needle electrode array model is developed for large and deep tumors. Real life tissue size is modeled and electrode dimensions are taken from published literature. A constant field of 1200V/cm is applied and electric field and energy distribution is obtained for various electrode configurations. Results show that internal electrodes result in an extra 10% reduction in field and are more effective and multi-needle electrode arrays are effective for large tumors. These results will help improve electrochemotherapy techniques for clinical cancer applications that are not receptive to conventional therapies. I. INTRODUCTION Cancer is a group of diseases characterized by uncontrollable growth and spread of abnormal cells and when the spread is not controlled, it can lead to death. According to the American Cancer Society there were approximately 1.5 million cases of cancer esti- mated in 2010 in the US [1], a third of which resulted in death. Many powerful and promising drugs that have been developed to treat cancer have not been effective because of low efficiency, safety and side effects [2]. This necessitates novel alternate cancer treatment methods. Electroporation is a technique by which high intensity, short duration pulses are applied to temporarily open up pores in the membrane of cells to allow trans- port of therapeutic materials including drugs, antibodies and genes [3-5]. This technique was first investigated in the late eighties and early nineties where high amplitude expo- nential and square pulses were used to improve the efficacy of bleomycin, an antitumor