The direct effect of ultrasound upon Wilms' tumor in the rat.

The possible activation of immunologic defenses against tumor by local ultrasonic irradiation was investigated. Sonication of one tumor of a dual implant destroyed that tumor only with no contralateral effect. Injection of tumor cells previously sonicated in vivo did not induced immunity to subsequent challenge with live cells. Immunofluorescent staining of host kidneys for antibody complexes was negative. It was concluded that sonication was only effective when directly applied to the tumor.