Henry Ford Hospital Medical Journal


This report summarizes our preliminary experience at the Mallinckrodt Institute of Radiology treating 26 patients with metastatic tumors with hyperthermia and irradiation. Patients received 400 rad fractions given every 72 hours (twice weekly) for a total of 2400, 2800, 3200, or 4000 rad followed by hyperthermia. In addition, 18 lesions were treated according to a protocol designed by the Radiation Therapy Oncology Group (RTOG) for superficial measurable tumors to receive three doses of 500 rad followed by hyperthermia (six lesions) or irradiation alone (three doses of 600, 700, or 800 rad) every 72 hours. Hyperthermia was administered with 2450 MHz or 915 MHz microwave generators and appropriately designed surface applicators. Temperatures were maintained at 42.5°-43°C for 90 minutes at 72-hour intervals. Irradiation was delivered with 12 to 16 Mev electrons, as required by the size of the lesions, and occasionally with Cobalt 60. Our first protocol treated six lesions with a combination of irradiation and hyperthermia and 12 control lesions with radiotherapy alone. We observed that 1500 rad and hyperthermia together were not as effective as higher doses of irradiation alone. Better results were obtained on an intramural protocol that combined higher doses of irradiation with hyperthermia. The doses of radiation and heat delivered have been extremely well tolerated by normal tissues. Of the 34 sites treated, three (8%) developed blisters, three (8%) erythema only, three (8%) moist desquamation, and 14 (41%) dry desquamation. No instances of ulceration, necrosis, or severe fibrosis have been observed in the treated areas, even in the patients surviving over one year. We feel that additional clinical trials are warranted to assess the potential value of hyperthermia alone or combined with irradiation to treat selected cancer patients. Intensive efforts will be required to improve existing methods for delivery and measurement of heat to lesions more than 5 cm deep.