No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The effect of flattening filter free delivery on endothelial dose enhancement with gold nanoparticles
1. J. F. Hainfeld, F. A. Dilmanian, D. N. Slatkin, and H. M. Smilowitz, “Radiotherapy enhancement with gold nanoparticles,” J. Pharm. Pharmacol. 60(8), 977–985 (2008).
4. S. M. Moghimi, A. C. Hunter, and J. C. Murray, “Long-circulating and target-specific nanoparticles: Theory to practice,” Pharmacol. Rev. 53(2), 283–318 (2001).
5. D. W. Siemann, D. J. Chaplin, and M. R. Horsman, “Vascular-targeting therapies for treatment of malignant disease,” Cancer 100(12), 2491–2499 (2004).
8. E. E. Connor, J. Mwamuka, A. Gole, C. J. Murphy, and M. D. Wyatt, “Gold nanoparticles are taken up by human cells but do not cause acute cytotoxicity,” Small 1(3), 325–327 (2005).
9. S. H. Cho, “Estimation of tumour dose enhancement due to gold nanoparticles during typical radiation treatments: A preliminary Monte Carlo study,” Phys. Med. Biol. 50(15), N163–N173 (2005).
10. S. H. Cho, B. L. Jones, and S. Krishnan, “The dosimetric feasibility of gold nanoparticle-aided radiation therapy (GNRT) via brachytherapy using low-energy gamma-/x-ray sources,” Phys. Med. Biol. 54(16), 4889–4905 (2009).
11. B. L. Jones, S. Krishnan, and S. H. Cho, “Estimation of microscopic dose enhancement factor around gold nanoparticles by Monte Carlo calculations,” Med. Phys. 37(7), 3809–3816 (2010).
12. R. I. Berbeco, W. Ngwa, and G. M. Makrigiorgos, “Localized dose enhancement to tumor blood vessel endothelial cells via megavoltage x-rays and targeted gold nanoparticles: New potential for external beam radiotherapy,” Int. J. Radiat. Oncol., Biol., Phys. 81(1), 270–276 (2011).
13. E. A. Murphy et al., “Nanoparticle-mediated drug delivery to tumor vasculature suppresses metastasis,” Proc. Natl. Acad. Sci. U.S.A. 105(27), 9343–9348 (2008).
14. S. D. Perrault, C. Walkey, T. Jennings, H. C. Fischer, and W. C. W. Chan, “Mediating tumor targeting efficiency of nanoparticles through design,” Nano Lett. 9(5), 1909–1915 (2009).
15. W. Ngwa, G. M. Makrigiorgos, and R. I. Berbeco, “Applying gold nanoparticles as tumor-vascular disrupting agents during brachytherapy: Estimation of endothelial dose enhancement,” Phys. Med. Biol. 55(21), 6533–6348 (2010).
18. M. K. K. Leung, J. C. L. Chow, D. B. Chithrani, M. J. G. Lee, B. Oms, and D. A. Jaffray, “Irradiation of gold nanoparticles by x-rays: Monte Carlo simulation of dose enhancements and the spatial properties of the secondary electrons production,” Med. Phys. 38(2), 624–631 (2011).
19. F. Van den Heuvel, J. P. Locquet, and S. Nuyts, “Beam energy considerations for gold nano-particle enhanced radiation treatment,” Phys. Med. Biol. 55(16), 4509–4520 (2010).
22. R. I. Berbeco et al., “DNA damage enhancement from gold nanoparticles for clinical MV photon beams,” Radiat. Res. 178(6), 604–608 (2012).
Article metrics loading...
The aim of this study is to quantify and to compare the dose enhancement factor from gold nanoparticles (AuNP) to tumor endothelial cells for different concentrations of AuNP, and clinical MV beam configurations.
Tumor endothelial cells are modeled as slabs measuring 10 × 10 × 2μm. A spherical AuNP is simulated on the surface of the endothelial cell, within the blood vessel. 6 MV photon beams with and without the flattening filter are investigated for different field sizes, depths in material and beam modulation. The incident photon energy spectra for each configuration is generated using EGSnrc. The dose enhancement in the tumor endothelial cell is found using an analytical calculation. The endothelial dose enhancement factor is defined to be the ratio of the dose deposited with and without AuNPs.
It is found that clinical beam parameters may be chosen to maximize the effect of gold nanoparticles during radiotherapy. This effect is further amplified ∼20% by the removal of the flattening filter. Modulation of the clinical beam with the multileaf collimator tends to decrease the proportion of low energy photons, therefore providing less enhancement than the corresponding open field.
The results of this work predict a dose enhancement to tumor blood vessel endothelial cells using conventional therapeutic (MV) x-rays and quantify the relative change in enhancement with treatment depth and field size.
Full text loading...
Most read this month