The invention relates to whole-body hyperthermia systems for raising the body temperature of the entire body of an individual to a predetermined target temperature Tb and for stabilizing said body temperature at said target temperature Tb, said systems comprising an apparatus having a first thermal means for raising said body temperature at a rate of at least 1 °C/hour, and at least a second thermal means for further adjusting the body temperature to said target temperature Tb, wherein said second thermal means comprise a fluid circuit, which is at least partially within the individual, wherein a fluid, heated by a heat exchanger to a set temperature Tf, is circulated through said fluid circuit.
