Effects of microwave-induced local hyperthermia on mammary adenocarcinoma in C3H mice.

Microwave-induced hyperthermia was focused locally upon mammary adenocarcinoma implanted in C3H mice when the tumor reached 6 mm in diameter. In 54 treated mice, all tumors diminished in size after the first exposure (43 degrees, 45 min) and disappeared completely following the second treatment. No other effects from heat application were apparent. All the mice in the microwave-treated group survived the whole period of observation (4 months) without any evidence of tumor, while 18 nontreated controls died within 4 weeks after inoculation.