Cancer imaging methods and cancer treatment methods using thermotherapy and drug delivery are disclosed herein. In one embodiment, the temperature of heated tissue is determined from radio-frequency data from an ultrasound transducer based upon a change in backscattered energy of acoustic harmonics. In another embodiment, a plurality of nanocarriers containing an anti-tumor medication are administered to a patient, and are excited in a first non-thermal ultrasound mode and/or a second thermal ultrasound mode using an ultrasound source. In yet another embodiment, a plurality of nanoparticles are administered to a patient, then at least some of the nanoparticles are heated along with tissue at a site of a tumor, and a photoacoustic imaging unit is used to determine a temperature of the heated tissue at the site of the tumor.