Results of a non-controlled trial of hyperthermia combined with radiation for superficial tumours

Clinical results of thermoradiotherapy for soft tissue tumours

Thirty-one unresectable and/or recurrent soft tissue tumours in 27 patients underwent hyperthermia in combination with radiation therapy. Locoregional hyperthermia was administered once or twice a week for 40-60 min to a total of 2-14 sessions using RF capacitive or microwave heating equipment. Radiation therapy was given 10-20 min before hyperthermia at doses of 20.8 to 70 Gy. The mean +/- SD of the maximum, average, and minimum intratumour temperatures was 44.0 +/- 2.9 degrees C, 42.3 +/- 1.6 degrees C, 40.1 +/- 1.1 degree C respectively, and that of the percentage of the intratumour points that exceeded 41 and 43 degrees C was 66.0 +/- 33.6, and 31.0 +/- 26.1 respectively. Of the 31 tumours treated, 13 (42%) showed CR (complete regression), 10 (32%) PR (> 50 and < 100% regression) and 8 (26%) NC (< 50% regression). Since intratumour low density areas on post-treatment CT scans have been demonstrated to be a useful parameter for assessing tumour response to thermoradiotherapy, the presence of low density areas was also assessed. Low density areas were classified into the following three categories according to the percent area occupied in the maximal cross-section of the tumour: type I, < 50%, type II, 50-80%; type III, > 80%. Of 20 tumours evaluable, 6 (30%) exhibited type III change, 11 (55%) type II and 3 (15%) type I. All of the type III tumours demonstrated a marked response on follow-up or histopathological examination. The major complication associated with treatment was skin ulcer in two patients. The five-year survival of the total 27 patients and 18 patients who had no distant metastases at the start of treatment was 32 and 48% respectively. These results indicate the clinical benefit of thermoradiotherapy using RF capacitive or microwave equipment for locally advanced and/or recurrent soft tissue tumours.

Superficial microwave-induced hyperthermia in the treatment of chest wall recurrences in breast cancer

Our study concerns 42 patients with chest wall recurrences from breast cancer: 17 Stage 1 (less than 4 cm in diameter), 11 Stage 2 (more than 4 cm), seven Stage 3 (skin ulceration whatever tumor size), and seven Stage 4 (neoplastic lymphangitis and/or skin nodules covering chest wall beyond midline). All the patients were treated with 2450 MHz microwaves by means of a generator with 4 magnetrons (250 to 300 W) and arterial applicators delivering 5 to 10 W/cm2. Each applicator is coupled with an infrared thermometer allowing an atraumatic temperature control processed by a PC-compatible computer using a Turbo Pascal program. A temperature of 41.5 degrees C to 42.5 degrees C was maintained for 45 minutes from the skin surface to a 2.5-cm depth within tissues. Hyperthermia alone was done in four patients; hyperthermia was combined with chemotherapy in four patients, and with electrontherapy (2 X 450 cGy or 3 X 350 cGy/week) in 34 patients: tumor dose under 3000 cGy in seven patients and over 3000 cGy in 27 patients. We observed a complete response in 22 patients (52.3%), a partial response (greater than 50%) in 11 patients (26.1%), and no response in nine patients (21.4%). No complete response was observed in patients treated with hyperthermia alone or in conjunction with chemotherapy. The local control was demonstrated to be improved only in patients treated with hyperthermia and radiotherapy. The results were correlated with tumor stage: ten complete responses out of 12 Stage 1, and one complete response out of four Stage 4. We noted nine side effects completely reversible within a month with no late skin reaction. Our results show that hyperthermia can give improved local control without any morbidity in treating chest wall recurrences of breast cancer.

Characteristics of the response of soft tissue sarcoma to hyperthermia: the correlation between temperature distribution, radiological examination and histology

Nineteen patients with soft tissue sarcoma were treated by a combination modality of hyperthermia and radiation or chemotherapy. There were 26 treatment sites. The size of the tumours ranged from 2.5 x 2 cm to 24 x 26 cm. Hyperthermic treatments were given twice a week, for a total of five to 14 sessions. Twenty-one tumours were treated by hyperthermia combined with radiotherapy, 2 Gy daily, five times a week, for a total of 40-78 Gy. Three tumours were treated by hyperthermia and arterial infusion of adriamycin, 100-120 mg in five or six treatments. For the superficial tumours the complete response rate was 40 per cent, and for the deep-seated tumours 6.2 per cent. Among the 12 tumours with no response, nine in which the treatment was evaluated as effective histologically (necrosis of the tumour) and by X-ray CT findings (development of a prominent hypodensity area) were included. Six cases were studied to correlate the X-ray CT findings, angiography and histological findings before and after hyperthermic treatment. The data were also used to interpret the thermal curve. The increased hypodensity area was roughly proportional to the development of necrosis, but there was one case in which hypodensity was not correlated with the necrosis. On the contrary, even in the contrast-enhanced area around the tumour in which the presence of residual tumour was strongly suspected clinically, no tumour cells were visualized. Clinical evaluation of the effect by size of the tumour can be supplemented by CT findings and histology, but should be cautiously adopted.