Abstract
Wistar Female rats bearing DMBA induced mammary tumours were subjected to whole body hyperthermia 42°C dry heat exposure for 15 minutes daily for 6 weeks. The control group was maintained at a room temparature of 25°C. Hyperthermia induced significant growth stimulation of breast tumour compared to the controls. Plasma estradiol was slightly decreased while total T4 and TSH values remained unchangedin heat stressed rats. Plasma prolactin was significantly increased together with enhanced synthetic activity of pituitary prolactin cells. It is concluded that heat acting as stressor accelerates breast tumor growth, probably by influencing synthesis of prolactin. Therefore the hormone dependancy of tumours should be considered before hyperthermia is used as an anticancer modality.
