Prostate cancer ablation
Methods and systems for delivering electrical energy and controlled, mild hyperthermia to a prostate tissue of a patient for destruction of cancerous and/or hyperplastic tissue. A method includes positioning a plurality of electrodes in a target tissue region comprising the prostate tissue, and establishing an alternating electrical current flow through a volume of the prostate tissue to induce mild heating and destruction of cancerous cells in the volume.
1 . A method of delivering electric fields to a prostate tissue of a patient for preferential destruction of cancerous cells or hyperplastic tissue of the prostate, comprising:
positioning a plurality of electrodes in a target tissue region comprising the prostate tissue, the plurality comprising an array of needle electrodes advanced through the perineum of the patient and positioned in the target tissue region; and
differentially activating groups of electrodes of the plurality so as to establish an electrical current flow in a plurality of different directions through a volume of the prostate tissue and preferentially destroy cancerous or hyperplastic cells in the volume, the electrical current flow comprising a frequency of less than about 300 kHz.
2 . The method of claim 1 , wherein the positioning comprises advancing electrodes through guides of a template device.
3 . The method of claim 1 , wherein the positioning comprises positioning electrodes in the prostate tissue and adjacent to or around the urethra of the patient for treatment of benign prostatic hyperplasia (BPH).
4 . The method of claim 1 , comprising delivering electrical current substantially throughout the volume of the patient's prostate during treatment.
5 . The method of claim 1 , wherein the differentially activating comprises activating different groups of two or more electrodes of the array in seriatim.
6 . The method of claim 1 , wherein at least one of the groups of the plurality comprises three or more secondary electrodes positioned to at least partially define an ablation volume and a center electrode within the ablation volume, with current flow field established between the center electrode and the secondary electrodes extending radially outward from a current flow center.
7 . The method of claim 1 , comprising maintaining an average target tissue region temperature below 50 degrees C.
8 . The method of claim 1 , comprising maintaining for a period of treatment an average target tissue region temperature from about 40 degrees C. to about 48 degrees C.
9 . The method of claim 1 , comprising maintaining for a period of treatment an average target tissue region temperature from about 42 degrees C. to about 45 degrees C.
10 . The method of claim 1 , the alternating electrical current flow comprising a frequency of about 50 to about 250 kHz.
11 . The method of claim 1 , the alternating electrical current flow comprising a frequency of about 100 kHz.
12 . The method of claim 1 , further comprising:
positioning the array of needle electrodes at a first location in the target tissue region and differentially activating groups of electrodes to establish current flow through tissue at the first location; and
positioning the array of needle electrodes at a second location in the target tissue region and differentially activating groups of electrodes to establish current flow through tissue at the second location.
13 . The method of claim 12 , wherein the first location is distal to the second location.
14 . A system for delivering electric fields to a prostate tissue of a patient for treatment of prostate cancer or BPH, comprising:
a plurality of electrodes for advancement and positioning in a target tissue region of the patient comprising prostate tissue, the plurality comprising an array of needle electrodes advancable through the perineum of the patient and into the target tissue region;
a control system comprising a power source coupled to the electrodes, and a computer readable storage media comprising instructions that, when executed, cause the control system to:
provide electrical current to the electrodes so as to establish a current flow radially or in a plurality of different directions through a volume of the prostate tissue and to preferentially destroy cancerous or hyperplastic cells in the target tissue region;
maintain an average target tissue temperature of less than about 50 degrees C. during energy delivery.
15 . The system of claim 14 , further comprising instructions for differentially activating different groups of two or more electrodes of the array in seriatim.
16 . The system of claim 15 , wherein a group of electrodes comprises three or more secondary electrodes positioned to at least partially define an ablation volume and a center electrode within the ablation volume, with current flow field established between the center electrode and the secondary electrodes extending radially outward from a current flow center.
17 . The system of claim 14 , further comprising a feedback unit for detecting temperature in the target tissue region.
18 . The method of claim 17 , wherein the control unit and feedback unit are coupled so as to maintain an average target tissue region temperature from about 40 degrees C. to about 48 degrees C. during treatment comprising energy delivery.
19 . The system of claim 14 , further comprising a guide template device for positioning or advancing electrodes through the perineum and into the target tissue of the patient.
20 . The system of claim 14 , the alternating electrical current flow comprising a frequency of about 50 to about 300 kHz.
21 . The system of claim 14 , further comprising an imaging system.
22 . A system for delivering electric fields to a prostate tissue of a patient for treatment of prostate cancer or BPH, comprising:
a plurality of electrodes for advancement and positioning in a target tissue region of the patient comprising prostate tissue, the plurality comprising an array of needle electrodes advancable through the perineum of the patient and into the target tissue region;
a perineal template device comprising a plurality of guides for positioning or advancing electrodes through the perineum and into the target tissue of the patient;
a control system comprising a power source coupled to the electrodes, the control system configured to:
provide electrical current to the electrodes so as to establish a current flow radially or in a plurality of different directions through a volume of the prostate tissue for controlled mild heating and destruction of cancerous or hyperplastic cells in the target tissue region, the electrical current flow comprising a frequency of less than about 300 kHz.
23 . A method of delivering electric fields to a target tissue of a patient for preferential destruction of cancerous cells in the target tissue, comprising:
positioning a plurality of electrodes in the target tissue region, the plurality comprising an array of needle electrodes advanced through the patient's tissue and positioned in the target tissue region; and
differentially activating groups of electrodes of the plurality so as to establish an electrical current flow in a plurality of different directions through a volume of the target tissue and preferentially destroy cancerous cells in the volume, the electrical current flow comprising a frequency of less than about 300 kHz.