A method of treating cancer in an adult subject comprising an electromagnetic (EM) radiation treatment step of administering to the subject an effective dose of EM radiation of a frequency in the range of 430-440 MHz (UHF) within a period of ≦45 minutes, the EM radiation being provided by a UHF emitter defining an exposure region, wherein for the duration of the period the subject is reclined upon a horizontal or substantially horizontal surface, and wherein the surface and UHF emitter are arranged for relative movement such that the exposure region passes, continually or periodically, between a first position and at least a second position on the subject. The method may further comprise an auxiliary treatment step such as X-ray therapy or treatment with certain chemical agents such as oxidised glutathione (GSSG) and/or a precursor thereof (eg glutathione (GSH)) in combination with a non-toxic oxidising agent, and S-methyl-L-cysteine sulphoxide (SMCO)
