[Possibility of local control of breast cancer by microwave tissue coagulator (MTC)]

The tissue injury caused by microwave tissue coagulator (MTC) was assessed clinically and pathologically in a case of advanced breast cancer with skin invasion. On condition that the output was 10 watts and radiation lasted for 90 seconds at one time, temperature on breast skin was measured after each radiation. The maximum temperature was over 60 degrees C at the needle electrode and over 42 degrees C at 10 mm from the electrode after 21 radiations. From assessment of the resected specimen after operation, the following results were obtained. The mechanism of tissue injury by MTC consists of direct heat injury and infarct by circulatory disturbance. The extent of injury from the needle electrode is approximately 10 mm in the former mechanism and 15 mm in the latter. In conclusion, MTC is useful for the therapy of local recurrence of the breast cancer because of effectiveness in control of tumor-oozing and occurrence of tumor necrosis.