Device for transurethral thermal therapy

An intraurethral catheter shaft comprises a plurality of lumens extending between a first end and a second end of the shaft. An antenna lumen has a generally circular cross-sectional surface area and is positioned nearer a first outer surface than a second outer surface of the catheter shaft. A first and second pair of cooling lumens substantially surround the antenna lumen and have a generally arc shaped cross-sectional surface area. The cooling lumens are configured to be circumjacent to the antenna lumen about a substantial majority of the antenna lumen. A urinary drainage lumen is positioned between the second pair of cooling lumens adjacent the antenna lumen and has a generally circular cross-sectional surface area. The lumens of the catheter shaft are defined by a unitary wall having a substantially uniform thickness throughout the catheter.