RF and MW Systems for Hyperthermia of Challenging Tumour Locations

Hyperthermia (i.e. heating of tumour tissue to 40-43°C) is used in clinical oncology to enhance the therapeutic effect of chemotherapy and radiotherapy. Many tumour sites are heated either by a single RF or MW antenna positioned on the tumour location, or by a phased array positioned around the patient. Superficial tumours are generally heated with MW antennas (4342450 MHz) and deep seated tumours with RF antennas (70-150 MHz). These devices cover the major, more common tumour sites, but more rare locations require more dedicated applicators. We discuss dedicated RF and MW systems aiming for heating semideep seated tumours in the leg, breast and upper thorax. Clinical results show that adequate heating is possible with these systems, with achieved temperatures in the therapeutic range.