Bioelectromagnetism is the interaction and phenomena that occurs between living organisms and electromagnetic fields. This area of research is being used to manufacture new cancer treatments which prioritise patient safety and comfort. By applying electromagnetic fields, we minimise the damage done to surrounding healthy cells by only targeting the tumour.
One form of this cancer treatment is proton beams. Protons are delivered to the body with circular accelerators to deliver high dosage rates to “hidden” tumours. Circular accelerators use radio frequency quadrupoles (4 electrodes arranged in each pole) and oscillating electric fields so that the beam of protons is simultaneously focusing and defocusing in perpendicular planes. With a wide range of 70 to 230 MeV, proton beam therapy can target tumours in 3 dimensions with minimal toxicity. Currently, there are trials which are testing proton beam therapy on patients with leptomeningeal metastasis (cancer of the meninges).
Another method being researched is linear accelerators to accelerate electrons to higher energy levels, producing a photon beam for cancer therapy. To deliver the therapeutic rays, high speed electrons are passed through multiple ring-shaped ferrite cores which are magnetized by high current pulses, to focus the rays on the tumour. Inside the body, the Lorentz force (force acted on an object due to electromagnetic fields) causes secondary electrons to move perpendicular to their velocity direction, creating asymmetry in the beam resulting in significant dose variation in the tumour. This method uses a MR-LINAC device, combining magnetic resonance imaging (MRI) and linear accelerators to track the effect of the cancer treatments in real time. Scientists split the magnetic field to avoid interference with the magnetic field so that MR imaging is successfully integrated into the treatment. Doctors are thus able to mark and monitor anatomical changes in tumours and attempt to reduce the effect of it on healthy cells.
Another possible cancer treatment is tumour treating fields (TTF): low-intensity intermediate frequency electrical fields to disrupt cell division, delaying the uncontrollable growth of cancer cells. Typically, TTF uses alternating electrical fields created by insulating electrodes to disrupt the dipole alignment in mitosis. Due to the presence of the electrodes and the electric field, the polar molecules and organelles migrates to the electric field, disrupting telophase. This process is known as dielectrophoresis. TTF can also disrupt mitosis by delaying DNA repair or inhibiting cell metabolism. Currently, TTF is approved to treat Glioblastoma Multiforme, one of the most common brain tumours in the UK. Here, waves of 100-300 kHz with an intensity of 1-3 V/cm exert a biophysical force on dipoles. TTF therapy ablates the primary cilia on Glioblastoma cells. By ablating the cilia, tumour growth is delayed and impedes chemoresistance.
Overall, bioelectromagnetism is a developing research area for cancer treatment that shows significant potential. As of now, there aren’t very many disadvantages to using bioelectromagnetism to treat cancer apart from expenses and that it may not be very accessible to all patients. Yet this is a vital area of cancer research as it aims to make cancer treatments safer for healthy body cells.
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