Methods and apparatuses for delivering tumor treating fields to a subject's body for near-surface tumors

1. A computer-implemented method for determining a location of a transducer on a subject's body for applying tumor treating fields, the method comprising:

determining a near-surface portion of a tumor in the subject's body, the near-surface portion of the tumor closer to a surface of the subject's body than other portions of the tumor;

determining a near-tumor position on the subject's body, the near-tumor position on the subject's body closer to the near-surface portion of the tumor than other positions of the subject's body;

determining, for a first transducer of a pair of transducers to be located on the subject's body for applying tumor treating fields, an outer perimeter of the first transducer, the first transducer comprising a plurality of electrode elements electrically coupled to each other, the plurality of electrode elements of the first transducer being located within the outer perimeter; and

identifying a portion of the outer perimeter of the first transducer to be located substantially at the near-tumor position on the subject's body.

2. The method of claim 1 , wherein the near-surface portion of the tumor is less than or equal to 80 mm from the near-tumor position on the subject's body.

3. The method of claim 2 , further comprising:

determining a central portion of the first transducer located centrally within the outer perimeter of the first transducer;

determining a power density at the portion of the outer perimeter of the first transducer and a power density at the central portion of the first transducer when applying tumor treating field to the subject's body,

wherein the power density at the portion of the outer perimeter of the first transducer is 100% to 300% of the power density at the central portion of the first transducer.

4. The method of claim 1 , wherein, for a line segment having first and second end points on opposite sides of the subject's body and intersecting the near-surface portion of the tumor, the first end point intersecting the near-tumor position on the subject's body, a distance between the first end point and the near-surface portion of the tumor is equal to or less than 50% of a distance between the second end point and the near-surface portion of the tumor.

5. The method of claim 1 , wherein a surface area of the first transducer is equal to or greater than 5000 mm 2 .

6. The method of claim 1 , wherein the first transducer is configured to be positioned over the subject's body with a face of the first transducer facing the subject's body;

wherein, when viewed from a direction perpendicular to the face of the first transducer, the near-surface portion of the tumor is substantially within the outer perimeter of the first transducer.

7. The method of claim 1 , wherein the near-tumor position on the subject's body is substantially within the outer perimeter of the first transducer and is located at a distance from the outer perimeter that is from 0% to 50% of the distance from the outer perimeter to the centroid of the transducer.

8. The method of claim 1 , wherein the first transducer is configured to be positioned over the subject's body with a face of the first transducer facing the subject's body;

wherein, when viewed from a direction perpendicular to the face of the first transducer, a number of the electrode elements of the first transducer are peripheral electrode elements defining the outer perimeter of the first transducer, the peripheral electrode elements substantially surrounding any other electrode elements of the first transducer.

9. The method of claim 1 , wherein at least one of the electrode elements of the first transducer touches the portion of the outer perimeter of the first transducer to be located substantially at the near-tumor position on the subject's body.

10. The method of claim 1 , wherein the portion of the outer perimeter of the first transducer to be located substantially at the near-tumor position on the subject's body is 20% or less of the outer perimeter.

11. The method of claim 1 , wherein the outer perimeter of the first transducer is substantially square, rectangular, regular polygonal, irregular polygonal, circular, oval, ovaloid, ovoid, or elliptical in shape.

12. The method of claim 1 , further comprising:

identifying a plurality of portions of the outer perimeter of the first transducer to be located substantially at the near-tumor position on the subject's body;

selecting at least one of the plurality of portions of the outer perimeter of the first transducer; and

outputting the selected at least one of the plurality of portions of the outer perimeter of the first transducer to determine the location of the transducer on a subject's body for applying tumor treating fields.

13. The method of claim 1 , further comprising:

identifying a plurality of orientations of the first transducer on the subject's body to substantially locate the portion of the outer perimeter of the first transducer at the near-tumor position on the subject's body;

selecting at least one of the plurality of orientations of the first transducer; and

outputting the selected at least one of the plurality of orientations of the first transducer to determine the location of the transducer on a subject's body for applying tumor treating fields.

14. The method of claim 1 , wherein the electrode elements are capacitively coupled.

15. The method of claim 1 , wherein the tumor is located in a head of the subject's body.

16. The method of claim 1 , wherein the tumor is located in a torso of the subject's body.

17. A computer-implemented method for determining a location of a transducer on a subject's body for applying tumor treating fields, the method comprising:

determining, for a first transducer of a pair of transducers to be located on the subject's body for applying tumor treating fields, an edge of the first transducer, the first transducer comprising an array of electrode elements electrically coupled to each other;

determining a near-surface location of a tumor in the subject's body and a closest near-tumor position on a surface of the subject's body; and

identifying, when viewed from a direction perpendicular to a face of the first transducer to be positioned over the subject's body, a segment of the edge of the first transducer that substantially overlaps the near-surface location of tumor, the segment of the edge being closer to the near-tumor position on the surface of the subject's body than a centroid of the first transducer.

18. The method of claim 17 , wherein, when viewed from the direction perpendicular to the face of the first transducer, the near-tumor position on the surface of the subject's body is located at a distance from the edge of the transducer that is from 0% to 50% of the distance from the edge of the transducer to the centroid of the transducer.