Abstract: A method of medical treatment of the prostate provides an ablation apparatus. The ablation apparatus includes a cannula, an electrode at least partially positioned in the cannula, and an insulation sleeve positioned in a surrounding relationship to at least a portion of the electrode. A distal end of the cannula is positioned in a rectum of a patient. The distal end of the cannula is advanced through a rectal wall of the rectum. A distal end of the electrode if advanced from the cannula into the prostate. Electromagnetic energy is delivered from the electrode to the prostate and an ablation zone is created in the prostate.

Abstract: A multiple antenna ablation apparatus includes an electromagnetic energy source, a trocar including a distal end, and a hollow lumen extending along a longitudinal axis of the trocar, and a multiple antenna ablation device with three or more antennas. The antennas are initially positioned in the trocar lumen as the trocar is introduced through tissue. At a selected tissue site the antennas are deployable from the trocar lumen in a lateral direction relative to the longitudinal axis. Each of the deployed antennas has an electromagnetic energy delivery surface of sufficient size to, (i) create a volumetric ablation between the deployed antennas, and (ii) the volumetric ablation is achieved without impeding out any of the deployed antennas when 10 to 50 watts of electromagnetic energy is delivered from the electromagnetic energy source to the multiple antenna ablation device. At least one cable couples the multiple antenna ablation device to the electromagnetic energy source.

Abstract: An ablation treatment apparatus has a multiple antenna device. The multiple antenna device includes a primary antenna with a lumen, a longitudinal axis and an ablative surface area of length L.sub.1. The multiple antenna device also includes a secondary antenna that is positioned in the primary antenna as the primary antenna is introduced through tissue. A secondary antenna distal end is deployed at a selected tissue site from the primary antenna lumen in a lateral direction relative to the longitudinal axis. A sensor is at least partially positioned at an exterior of the secondary antenna distal end at a distance L.sub.2 from the primary antenna along the secondary antenna distal end. L.sub.2 is at least equal to 1/3 L.sub.1. An energy source is coupled to the primary antenna.

Abstract: An ablation treatment apparatus has a multiple antenna device with a primary antenna and a secondary antenna. The secondary antenna is positioned in a lumen of the primary antenna as the primary antenna is introduced through tissue to a selected tissue site. At the tissue site the secondary antenna is deployed from the primary antenna in a lateral direction relative to a longitudinal axis of the primary antenna. At least a portion of a distal end of the secondary antenna is structurally less rigid than the primary antenna. The primary antenna is constructed to be rigid enough to be introduced and advanced through tissue. A cable couples the energy source to one or more of the antennas.