Tumor eradication by radiofrequency therapy. Responses in 21 patients.

Tumor blood flow, measured by an isotope dilution technique, is only 2% to 15% of that of the surrounding tissue. This sluggish circulation differentiates cancer from normal tissue and forms the basis for a new therapy that entails the transfer of radiofrequency (RF) energy for heating tissues locally. The heated tissue is cooled by the circulation of blood, which carries away the heat. Impaired perfusion, as in cancers, impedes cooling. Heating by RF elevated the temperatures of animal and human cancers by 5 to 9.5 C above that of healthy tissue. The heat eradicated the animal cancers without destruction of normal tissue. Radiofrequency therapy produced tissue necrosis or substantial regression of cancer in 21 patients.