Ex vivo distribution of gold nanoparticles in choroidal melanoma

Mozhgan Rezaei Kanavi,1 Somayeh Asadi,1,2 Hamid Ahmadieh2 1Ocular Tissue Engineering Research Center, 2Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IranStudies on combined radiotherapy and nanoparticles (NPs) have shown that a greater therapeutic ratio can be achieved using gold nanoparticles (GNPs) as radiosensitizing agents within the tumor.1 Recent Monte Carlo studies demonstrated that GNPs enhance the absorbed dose by choroidal melanoma during brachytherapy with sources such as 103Pd and 125I.2 Given that the energy range of these sources is low, NPs with high atomic number can be suitable to yield a higher absorbed dose when used alongside the mentioned sources.3 Although it has been a long time since the merit and priority of using NPs in treating cancer by low-energy sources has been studied, regarding eye cancers a major concern has been the way these NPs would be spread in the ocular tissues. A principal question is the form and method by which the NPs disperse within the intraocular tumor after intralesional injection. Will the NPs be also absorbed by the nearby healthy tissues?