This invention provides a dual-modality system for imaging target tissue, e.g. for the detection of cancerous tissues. Ultrasound technology comprising at least two focused ultrasound beams (108, 110) for vibrating target tissues located at the focal point (112) of the ultrasound beams intersection is coupled with a radio frequency (RF)system (102) 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. A cancellation module (138) is provided to eliminate the main carrier tone of the reflected RF signal as well as signal leakage from the transmit antenna (130), leaving only the sidebands that are generated due to the Doppler shift resulting from the vibration of the target tissues when subjected to the focused ultrasound waves.