Injectable and Repeatable Inductive Heating of Iron Oxide Nanoparticle-Enhanced "PHIL" Embolic toward Tumor...

Area of Science:

• Biomedical Engineering
• Oncology
• Nanotechnology

Background:

• Deep-seated tumors often recur after primary treatments, necessitating invasive repeat therapies.
• Current treatment options for recurrent tumors can be traumatic and have limitations.

Purpose of the Study:

• To develop and evaluate an iron oxide nanoparticle (IONP)-enhanced precipitating hydrophobic injectable liquid (PHIL) as a localized, repeatable thermal ablation implant.
• To assess the feasibility of dual treatment via nutrient deprivation and thermal ablation for recurrent tumors.

Main Methods:

• Created an injectable, stable PHIL-IONP solution.
• Monitored PHIL-IONP deposition using micro-computed tomography (μCT).
• Gauged IONP distribution within the embolic using magnetic resonance imaging (MRI).
• Evaluated thermal ablation capabilities in model systems and ex vivo tumors.

Main Results:

• Successfully created a stable, injectable PHIL-IONP solution.
• Demonstrated non-invasive monitoring of PHIL-IONP deposition and distribution.
• Achieved therapeutic temperatures (>8 °C elevation, clinically ~45 °C) for thermal ablation in model disks and 3D tumor beds.
• Confirmed repeatable heating over a month without affecting heat output.
• Ex vivo mouse tumors showed ablative temperatures (17 °C elevation, clinically 54 °C) maintained for over 15 minutes.

Conclusions:

• PHIL-IONP offers a promising localized, dual-treatment implant for recurrent deep-seated tumors.
• The implant enables multiple, repeatable thermal ablation sessions with sustained therapeutic temperatures.
• This approach presents a less invasive alternative to repeated conventional cancer treatments.