Figure 4

The figure represents the ratio between the energy consumption of a cancer cell inside the magnetic field (50 μT, 40 Hz) and outside of it; the y-axis is the quotient of the x-axis of Fig. 3(a,b), with the x-axis again depicting the volumetric increase of the resulting tumor.

It is evident that tumor tissue consumes much more energy at the early growth stages, which supports the temporary effectiveness of the magnetic field therapy that rapidly diminishes at later, more advanced tumor growth stages, hence advocating for applying this therapeutic modality early on in the treatment cycle (see also Fig. 3). While this treatment response is reflected in the flux patterns of all four ions, it is conceivable to pinpoint the maximum benefit of the magnetic field to the largest ratio between the Na⁺ and Ca²⁺ fluxes which may have diagnostic value (note that the Na⁺ and Cl⁻ fluxes are superimposed in the figure). As to the tumor, based on Eq. (16) and Fig. 1, we argue that rapid cancer cell proliferation dominates early on whereas marked apoptosis impacts the result at later stages. (Note: due to the current setup, we are unable to assign a distinct weight to the relative contributions to [total] energy consumption of intrinsic tumor growth vs. therapeutic impact of the magnetic field, an area that we would like to explore in future works).