A catheter for use in a system for treating tissue in a body using direct current ablation comprising: a tubular body having a proximal end and a distal end and being chemically resistant to pH below pH 5 and above pH 9, wherein the tubular body has a flex modulus of between 0.5 and 3 GPa, the tubular body comprising: a tip positioned at the distal end; a plurality of electrodes; an electrical connection to the electrodes; an inner sheath; an outer sheath chemically resistant to pH below pH 5 and above pH 9; an electrode director attached to the outer sheath and comprising a plurality of routing holes, wherein the routing holes comprise radiused channels and wherein the shape and orientation of the radiused channels are configured to direct the electrodes from the catheter into the tissue at a pre-determined angle; a first fixation element operably coupled to the tubular body, wherein the first fixation element is configured to fix the catheter in place in the body during treatment of the tissue; and an electrode driver mechanically coupled to the inner sheath and wherein the electrodes are fixed to the electrode driver; wherein the catheter is configured for linear electrode deployment such that relative longitudinal movement between the inner sheath and the outer sheath deploys the plurality of electrodes through the plurality of routing holes in the electrode director and into the tissue. a tubular body having a proximal end and a distal end and being chemically resistant to pH below pH 5 and above pH 9, wherein the tubular body has a flex modulus of between 0.5 and 3 GPa, the tubular body comprising: a tip positioned at the distal end; a plurality of electrodes; an electrical connection to the electrodes; an inner sheath; an outer sheath chemically resistant to pH below pH 5 and above pH 9; an electrode director attached to the outer sheath and comprising a plurality of routing holes, wherein the routing holes comprise radiused channels and wherein the shape and orientation of the radiused channels are configured to direct the electrodes from the catheter into the tissue at a pre-determined angle; a first fixation element operably coupled to the tubular body, wherein the first fixation element is configured to fix the catheter in place in the body during treatment of the tissue; and an electrode driver mechanically coupled to the inner sheath and wherein the electrodes are fixed to the electrode driver; a tip positioned at the distal end; a plurality of electrodes; an electrical connection to the electrodes; an inner sheath; an outer sheath chemically resistant to pH below pH 5 and above pH 9; an electrode director attached to the outer sheath and comprising a plurality of routing holes, wherein the routing holes comprise radiused channels and wherein the shape and orientation of the radiused channels are configured to direct the electrodes from the catheter into the tissue at a pre-determined angle; a first fixation element operably coupled to the tubular body, wherein the first fixation element is configured to fix the catheter in place in the body during treatment of the tissue; and an electrode driver mechanically coupled to the inner sheath and wherein the electrodes are fixed to the electrode driver; wherein the catheter is configured for linear electrode deployment such that relative longitudinal movement between the inner sheath and the outer sheath deploys the plurality of electrodes through the plurality of routing holes in the electrode director and into the tissue.