Hyperthermia is one of the many approaches currently being tested for cancer therapy. The goal of this approach is to heat specifically and exclusively the local tumor region by means of the magnetic losses of magnetic nanoparticles in an external, alternating magnetic field, doing it without damaging the surrounding healthy tissue.

Regarding the energy loss in the magnetic material, there are two different effects to be considered:

a) magnetic losses through domain wall displacements (in multi-domain particles) called Néel losses; and

b) energy loss from mechanical rotation of the particles, acting against viscous forces of the liquid medium (Brown losses).

Both effects add up so the lost energy is converted into HEAT.

The technique that uses the above mechanisms to induce heating of living tissues is often called Magnetic Fluid Hyperthermia.

The Magnetic Fluid Hyperthermia (MFH) is one among many techniques used in oncology, based on heating tissues for therapeutic purposes. MFH is usually used as an additive therapy with standard treatments (radiotherapy, for example), and some preliminary studies have showed that the combination of radiation plus hyperthermia lead to increased results regarding tumoral regression. Some countries already define hyperthermia as an autonomous therapy, with levels of efficiency comparable to chemotherapy.

There are many techniques involving laser, ionizing radiation, and microwaves as tools to heat up body (malignant) tissues. Although these techniques are capable of rising the intracellular temperature up to the cellular death, they may have unwanted collateral effects such as ionization of genetic material (radiation) or lack of selectiveness (microwaves) that affect the surrounding healthy tissues.

A different approach, developed mostly along the last decade, is the selective thermo-cytolysis based on the process of magnetic losses. This strategy, called magneto-thermo-cytolysis or magneto-thermoablation, is a promising technique thanks to the development of precise methods for synthesizing functionalized magnetic nanoparticles (FMNPs).

Magnetic nanoparticles with functionalized surfaces (so to attach with high specificity to a given tissue) are used for hyperthermia treatments seeking their accumulation only in tumor tissue. Depending on the success in solving this biochemical and physiological specificity-problem, cancer-specific hyperthermia protocols could be developed.