Radio frequency hyperthermia of advanced human sarcomas

Hyperthermia greater than or equal to 42 degrees C is tumoricidal in vitro and in many animal models, although such temperatures have only recently been achieved experimentally in some human cancers. A recently developed radio frequency device that provides safe hyperthermia to any depth without surface tissue injury now permits evaluation of the effects of hyperthermia on advanced human sarcomas. Twelve patients with large sarcomas located intraabdominally [7], in the chest wall [2], proximal extremity [2], and the neck [1], were evaluated in this study. Tumor types include liposarcoma [3], rhabdomyosarcoma [2], leiomyosarcoma [2], neurofibrosarcoma [2], and one each malignant mesothelioma, undifferentiated sarcoma, and osteosarcoma. Intratumor temperatures greater than or equal to 42 degrees C were observed in all tumors, with virtually no normal tissue injury. Selective tumor heating greater than or equal to 45 degrees C occurred in 9/12 (75%) and greater than or equal to 50 degrees C in 6/12 (50%). One to five weekly treatments greater than or equal to 50 degrees C and ten daily treatments greater than or equal to 45 degrees C resulted in significant tumor necrosis and pain relief in some patients. Hyperthermia of advanced sarcomas is possible with little host toxicity and may be of potential therapeutic benefit.