Evaluation Efficacy of Rhenium-188-Loaded Micro-particles for Radiotherapy in a Mouse Model of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the leading causes of mortality worldwide. The aim of the present study was to evaluate the distribution and the therapeutic effect of 188Re-Tin-colloid micro-particles in subcutaneous HCC-bearing mice. The synthesis and characterization of micro-particles labeled with the 188Re isotope were performed. The micro-particles were injected into the tumor site subcutaneously in the BNL HCC-bearing mice with three treatment groups, normal saline, 188Re micro-particles, and 188Re-Tin-colloid micro-particles. The results of biodistribution showed that major radioactivity (188Re) of 188Re-Tin-colloid micro-particles (18.69 ± 4.28 %ID/g) remained at the tumor sites, compared with 188Re micro-particles (0.21 ± 0.12 %ID/g), 24 h post injection. Following the injection of 188Re-Tin-colloid micro-particles for 14 days, all BNL tumors in mice were regressed during the observation period. By contrast, all of the mice treated with normal saline or 188Re micro-particles had died by 24 and 28 days, respectively. The 188Re-Tin-colloid micro-particles demonstrated high accumulation and therapeutic potential in the subcutaneous HCC-bearing mice.