This invention provides a dual-modality system for performing characterization and imaging of tissue, tumors, structures, lesions, and ablations under investigation. Specifically, the invention couples ultrasound technology comprising at least two focused ultrasound beams for vibrating target tissues located at the focal point of the ultrasound beams intersection with a radio frequency system for measuring the response of the target tissues. The ultrasound system vibrates the target tissues while the reflected radio frequency energy is transmitted into the target tissues. When reflected, the main carrier tone of the reflected radio frequency energy is cancelled and analysis is performed on the remaining sideband frequencies.