An in vitro and in vivo investigation of the biological behavior of a ferrimagnetic cement for highly focalized thermotherapy

Abstract

The cancer treatment by local hyperthermia, using a high frequency electromagnetic field is an extensively studied subject. For this propose it was developed a ferrimagnetic cement (FC) to be injected directly into the tumor. In this study it was determined the FC injectability, its capability to generate heat when placed within a magnetic field and its interaction with a modified simulated body fluid using SEM/EDS and XRD. The FC biological response was assessed by the intramuscular implantation in rats and histological analysis of the surrounding tissues. The results suggest that FC can be injected directly into the tumor, its temperature can be increased when exposed to a magnetic field and the surface of the immersed samples quickly becomes coated with precipitate denoting its ionic change with the surrounding medium. The histological analysis revealed a transient local inflammatory reaction, similar to the control material, only slightly more abundant during the first weeks, with a gradual decrease over the implantation time. Based on these results, we concluded that FC might be useful for highly focalized thermotherapy, with a good potential for clinical use.

In situ forming implants for local chemotherapy and hyperthermia of bone tumors

“…The heat produced when it was exposed to an alternating magnetic field (10 kHz) corresponded to a specific heat power of 2.11 W/g in vitro [230].…”

“…Maximum specific heating power = 2.11W/g  Biocompatible (9 weeks) [230] Abbreviations: AMF: alternating magnetic field; AC: Acrylic cements; CPC: calcium phosphate cements; bis-GMA: bis-α-glycidylmethacrylate; HA: hydroxyapatite; SBF: simulated body fluid n.r. : not reported * Magnetic field amplitude is converted to milltesla (10 Oe = 1 mT)…”

Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic. Part I: Morphological, mechanical and calorimetric characterization

“…[19][20][21] A ferromagnetic bone cement containing Fe 3 O 4 and SiO 2 glass microparticles dispersed in a bis-glycol methanlacrylate acrylic resin has been developed. 11,22 Another interesting graft material is a PMMA bone cement for controlled hyperthermia consisting of PMMA, ferromagnetic and/or superparamagnetic particles with at least one biodegradable or biocompatible crystalline substance has been patented by Vogt et al 23 Finally, calcium phosphate cement containing Fe 3 O 4 powders 24 and ferrimagnetic silicate cement 25 were also proposed for cancer treatment by localized hyperthermia.…”

A review of calcium phosphate cements and acrylic bone cements as injectable materials for bone repair and implant fixation

“…The injectability of CPCs is commonly assessed using the syringe ejection method. [124][125][126][127] For example, Wang et al 127 used a needle with an inner diameter of 1.6 mm for injectability measurements. The as-prepared paste was poured into the syringe 2 min after mixing the cement powder and liquid.…”

“…Various magnetic materials, such as magnetite (Fe 3 O 4 ), have been shown to generate heat in an alternating magnetic field. 125,195 Hence, these materials have been widely studied for the minimally invasive treatment of cancer through hyperthermia of metastatic bone tumors. 202,203 Adding magnetite has shown to increase the setting time of PMMA cement and decrease the maximum temperature during setting.…”