ULTRASOUND POTENTIATION OF CHEMOTHERAPY FOR BRAIN MALIGNANCY

One of the earliest uses of ultrasound was for treatment of malignancies. Starting in 1938 S. Hayashi(4, 5) and other Japanese investigators(17, 20) reported its effectiveness in decreasing growth rates in several reproducible animal tumors. From 1944 to 1949 German and Swiss investigators including Horvath(7–13), Horatz(14), Pohlman(18), Woeber(23, 24), and others reported trials of ultrasound therapy for a variety of human tumors primarily those involving the skin. Although there appeared to be initial improvement in some basal cell carcinomas and sarcomas, the lesions returned in a few months. The recent memory of x-ray burns kept these investigators from giving repeated doses of ultrasound for fear of producing irreversible skin damage. After a few cases of increased tumor growth rate during ultrasound therapy were reported, the “Erlanger Resolution”(3, 18) was passed in 1949 stating that ultrasound was not suitable for tumor therapy, except for carefully controlled animal model studies. A monograph compiled by Pohlman in 1952(18) reported 133 cases collected from the literature of ultrasound therapy for malignant tumors. Although skin lesions appeared to be the most frequent of these, no complete designation of the types of tumors or ultrasound parameters is included in this report. Pohlman found that 1.5% of the 133 had striking improvement, 15.8% were improved, 57.2% showed no change, 6.7% were made worse and no conclusion could be drawn in 18.8%.