Inhibition of whole body hyperthermia with far-infrared rays of the the growth of spontaneous mammary tumors in mice.

Experimental Animal Research Laboratory, Meiji university, Kawasaki, Japan. Sept-Oct. 1999

To evaluate possible therapeutic benefits of irradiation with far-infrared rays (FIR) on breast cancer, we examined combined effects of the chronic exposure to FIR (WBH) (35-41 degrees C) on the growth of spontaneous mammary tumors of mice. A high mammary tumor strain of SHN virgin mice born on the normal rack of FIR rack were maintained on the respective racks until mammary tumor appearance.

When the mammary tumor size reached approximately 7 mm, some mice in each group received no further treatment (Control and FIR groups, respectively) and the remaining mice received 3 hours of WBH each for 5 consecutive days (C + WBH and FIR + WBH groups, respectively). There was little difference between the control and FIR groups in the tumor growth over 10 days of examination.

On the other hand, the tumor growth was inhibited significantly in both C + WBH and FIR + WBH groups and the degree of inhibition was similar. The data confirmed that the chronic exposure to FIR at ambient temperature has little effect on the growth of spontaneous mamary tumors in mice. WBH with FIR, however, strongly inhibited the tumor growth without deleterious side-effects, while chronic FIR irradiation itself again had little effect in this process. This WBH regimen may serve as a useful animal model for long-term studies of a non-invasive treatment of breast cancer.