This phase I study aimed to determine the recommended dose (RD), safety profile, and feasibility of a procedure combining intratumoral injection of hafnium oxide nanoparticles (NBTXR3; a radioenhancer) and external beam radiotherapy (EBRT) for preoperative treatment of adults with locally advanced soft tissue sarcoma (STS). Patients had a preoperative indication of EBRT for STS of the extremity or trunk. Baseline tumor volume (TV) was calculated by MRI. NBTXR3 was injected percutaneously into tumors at 53.3 g/L. Dose escalation was based on four levels equivalent to 2.5%, 5%, 10%, and 20% of baseline TV. NBTXR3 was visualized in the tumor 24 hours postinjection, and EBRT was initiated (50 Gy over 5 weeks).
There is considerable interest in approaches that could improve the therapeutic window of radiotherapy. In this study, hafnium oxide nanoparticles were designed that concentrate in tumor cells to achieve intracellular highenergy dose deposit. Materials & methods: Conventional methods were used, implemented in different ways, to explore interactions of these high-atomicnumber nanoparticles and ionizing radiation with biological systems.
Nanotechnology offers revolutionary strategies to improve healthcare. Adequate nanomaterial characterization constitutes the basis to establish relevant programs of nanoparticle/biological systems cross talk evaluation. Also, the surrounding conditions significantly impact on the state of the nanoparticles in terms of their collective behavior: dispersion, aggregation, and stability in gas or liquid.