A device for ablation-based cancer treatment, comprising at least one Radio Frequency, RF, coil (106, 206, 306) configured to generate alternating magnetic fields at RF frequencies in the range of 100 kHz to 200 MHz, wherein said RF coil (106, 206, 306) comprises a core material (205, 305) having a magnetic permeability of air or a magnetic permeability higher than air; at least one microwave, MW, antenna (101, 201, 301) configured to generate microwave electromagnetic waves comprising a combination of magnetic and electric fields, directable to a tumor region (125, 172, 307) of a subject, wherein the RF and microwave electromagnetic waves are configured to be absorbed by and thereby heat metallic nanoparticles configured to selectively accumulate in the tumor regions (125, 172, 307); and a control circuitry (108, 112) configured to: provide an electrical signal at RF frequencies to said RF coil, thereby defining properties of the electromagnetic waves generated by said RF coil; provide an electrical signal at microwave frequencies to said microwave antenna (101, 201, 301), thereby defining properties of the electromagnetic waves generated by said microwave antenna; obtain temperature information from a thermal sensor located in the tumor region and from a thermal sensor located in the healthy tissue; and adjust one or more properties of the RF and/or microwave electromagnetic waves based on the obtained temperature information, the one or more properties including at least the frequency of the microwave electromagnetic waves comprising the combination of magnetic and electric fields. said RF coil (106, 206, 306) comprises a core material (205, 305) having a magnetic permeability of air or a magnetic permeability higher than air; at least one microwave, MW, antenna (101, 201, 301) configured to generate microwave electromagnetic waves comprising a combination of magnetic and electric fields, directable to a tumor region (125, 172, 307) of a subject, wherein the RF and microwave electromagnetic waves are configured to be absorbed by and thereby heat metallic nanoparticles configured to selectively accumulate in the tumor regions (125, 172, 307); and a control circuitry (108, 112) configured to: provide an electrical signal at RF frequencies to said RF coil, thereby defining properties of the electromagnetic waves generated by said RF coil; provide an electrical signal at microwave frequencies to said microwave antenna (101, 201, 301), thereby defining properties of the electromagnetic waves generated by said microwave antenna; obtain temperature information from a thermal sensor located in the tumor region and from a thermal sensor located in the healthy tissue; and adjust one or more properties of the RF and/or microwave electromagnetic waves based on the obtained temperature information, the one or more properties including at least the frequency of the microwave electromagnetic waves comprising the combination of magnetic and electric fields. provide an electrical signal at RF frequencies to said RF coil, thereby defining properties of the electromagnetic waves generated by said RF coil; provide an electrical signal at microwave frequencies to said microwave antenna (101, 201, 301), thereby defining properties of the electromagnetic waves generated by said microwave antenna; obtain temperature information from a thermal sensor located in the tumor region and from a thermal sensor located in the healthy tissue; and adjust one or more properties of the RF and/or microwave electromagnetic waves based on the obtained temperature information, the one or more properties including at least the frequency of the microwave electromagnetic waves comprising the combination of magnetic and electric fields.