Ferreira Maria Clara M, Podder Tarun K, Rasmussen Karl H, Jung Jae W
Department of Physics, East Carolina University, Greenville, NC.
Brachytherapy. 2013 Nov-Dec;12(6):654-64. doi: 10.1016/j.brachy.2013.06.007. Epub 2013 Aug 7.
To perform dosimetric study of (142)Pr microspheres for the use as a possible choice of radionuclide in microsphere brachytherapy of nonresectable hepatic tumor for faster dose delivery and facilitated dosimetry for quality assurance.
Dose distributions of (142)Pr and (90)Y microspheres within hepatic tumors and blood vessels were calculated using MCNPX2.6 Monte Carlo code. The biological effective doses (BEDs) for (142)Pr and (90)Y microspheres were calculated and compared using the linear-quadratic model.
Dose distributions due to beta particles were similar for both (142)Pr and (90)Y. Total initial activity required to achieve the same total dose of 150 Gy at 2 cm from the center of the tumor was 0.662 GBq and 0.191 GBq for (142)Pr and (90)Y, respectively. For α/β ratio equal to 10 Gy, calculated BED values were 301.0 and 194.7 for (142)Pr and (90)Y, respectively, considering a total physical dose of 150 Gy.
Total dose delivery and dose distributions for both (142)Pr and (90)Y within tumors and blood vessels were obtained and compared. Shorter half-life of (142)Pr is an advantage, enabling a faster dose delivery. The higher BED found for (142)Pr implies potential improvement in the treatment effectiveness. (142)Pr showed to be an attractive option for applications in microsphere brachytherapy.
