Improved nanoparticle injection model for magnetic hyperthermia cancer treatment

Magnetic hyperthermia is a promising treatment method for some cancerous tumors. In this treatment, magnetic nanoparticles (MNPs) are injected into the tumor and then exposed to an alternating magnetic field, which heats the nanoparticles and the surrounding tumor. This heat can either be used to kill the tumor cells directly or to augment another type of cancer treatment, such as chemotherapy.

Key to this treatment method is understanding the distribution of injected nanoparticles within the tumor. Tang et al. employed a series of numerical models to create a more realistic picture of nanoparticle distribution.

“Although magnetic hyperthermia has received attention in previous reports, the prediction of nanofluid concentration distribution inside a tumor still lacks comprehensive illustration,” said author Yundong Tang. “In fact, magnetic fluid distribution inside the biological tissue was assumed to be homogeneous, to be one or several spheres inside the tumor tissue, and also to be a normal distribution at the injection point.”

The authors developed two models, one using the Brinkman equation and another using the Navier-Stokes equation while simulating backflow, where the injected nanoparticles flow along the channel made by the injection needle as it withdraws. They tested both models under identical criteria, including nanofluid dose, maximum nanofluid concentration, and initial tumor conditions. They found that the model with backflow leads to a better magnetic fluid distribution, a better therapeutic temperature, and better heat-induced damage of the tumor tissue.

The authors hope their approach can be used to aid in predicting outcomes of magnetic hyperthermia therapies, increasing adoption of the technique.

Source: “Impact of different nanofluid injection models on thermal damage behavior during magnetic hyperthermia,” by Yundong Tang, Rodolfo C.C. Flesch, and Tao Jin, Journal of Applied Physics (2025). The article can be accessed at https://doi.org/10.1063/5.0290433 .