Effect of thermochemotherapy on the development of spontaneous lung metastases.

Effect of local hyperthermia given alone or in combination with cyclophosphamide and/or hyperglycaemia on the development of lung metastasis was studied using a non-immunogenic mouse fibrosarcoma, FSa-II. Incidence of lung metastasis was dependent upon the tumour size, and was increased when tumour-bearing mice were restrained in animal holders which were used for heat-treatment of animal tumours. The frequency of the metastatic spread was decreased following local hyperthermia at 41.5 degrees and 45.5 degrees C when compared to that following sham treatment. This decrease was independent of the heat dose. Similar reduction in the incidence of metastasis was observed after hyperthermia given following glucose administration. The administration of cyclophosphamide effectively inhibited the development of lung metastasis. However, the magnitude of the inhibition was identical to that following hyperthermia alone. In conclusion, hyperthermia given alone, or in combination with hyperglycaemia or cyclophosphamide, inhibited the development of lung metastasis.