Magnetic approaches to improve targeting efficiency of TAE for HCC*

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, accounting for 75–85[%] of global cases. Trans-arterial embolization (TAE) is a minimally invasive treatment in which microparticles loaded with chemotherapeutic or radioactive agents are delivered through the hepatic artery to block tumor-feeding vessels under image guidance.

Researchers have explored magnetic steering and magnetic thermal therapy (MTT) to enhance targeting and therapeutic efficacy, although these approaches have not yet been used in combination. MTT involves delivering magnetic particles (MPs) to the tumor and exposing them to an alternating magnetic field (AMF) to induce localized heating. Two MP delivery strategies have been studied: direct injection (DI) and TAE-MTT (with and without spatially confined heating (SCH)). While preclinical studies have demonstrated the potential of these techniques, clinical translation is limited by eddy current heating (ECH), which increases with torso size under AMF exposure and by off-target heating of MPs distributed in healthy liver tissue following hepatic-artery delivery can be minimized by Spatially targeting MPs in tumor using SCH. A computational model was developed to simulate MTT with ECH effects and conducted a factorial design study varying to optimize MP concentration, AMF duty cycle and period during DI. Optimal DI-MTT parameters were identified as a 25[%] duty cycle with a 60[s] period and 15[mg/mL] MP concentration. Using these parameters, TAE-MTT with SCH was modeled and compared to DI-MTT. DI achieved a 14.7[%] higher tumor coverage index than TAE. However, DI may be impractical for deep-seated tumors. TAE-MTT under the same conditions resulted in 6.25[%] healthy tissue damage. Incorporating SCH during TAE-MTT improved tumor damage by 12.1[%] while reducing healthy tissue damage to ~0[%]. Future work will focus on experimental validation of TAE-SCH-MTT in phantoms.