In silico dosimetry of low-dose rate brachytherapy using radioactive nanoparticles

Author(s)

Seniwal, Baljeet ^[1] ; Freitas, Lucas F. ^[2] ; Mendes, Bruno M. ^[3] ; Lugao, Ademar B. ^[2] ; Katti, V, Kattesh ; Fonseca, Telma C. F. ^[1]

Affiliation

^[1] Univ Fed Minas Gerais, Dept Engn Nucl, Av Antonio Carlos 6627, BR-31270901 Belo Horizonte, MG - Brazil

^[2] Nucl & Energy Res Inst, IPEN CNEN SP, Sao Paulo - Brazil

^[3] Nucl Technol Dev Ctr, CDTN BH MG, Belo Horizonte, MG - Brazil

• Document type: Journal article
• Source: Physics in Medicine and Biology; v. 66, n. 4 FEB 21 2021.
• Web of Science Citations: 0

Abstract

Purpose. Nanoparticles (NPs) with radioactive atoms incorporated within the structure of the NP or bound to its surface, functionalized with biomolecules are reported as an alternative to low-dose-rate seed-based brachytherapy. In this study, authors report a mathematical dosimetric study on low-dose rate brachytherapy using radioactive NPs. Method. Single-cell dosimetry was performed by calculating cellular S-values for spherical cell model using Au-198, Pd-103 and Sm-153 NPs. The cell survival and tumor volume versus time curves were calculated and compared to the experimental studies on radiotherapeutic efficiency of radioactive NPs published in the literature. Finally, the radiotherapeutic efficiency of Au-198, Pd-103 and Sm-153 NPs was tested for variable: administered radioactivity, tumor volume and tumor cell type. Result. At the cellular level Sm-153 presented the highest S-value, followed by Pd-103 and Au-198. The calculated cell survival and tumor volume curves match very well with the published experimental results. It was found that Au-198 and Sm-153 can effectively treat highly aggressive, large tumor volumes with low radioactivity. Conclusion. The accurate knowledge of uptake rate, washout rate of NPs, radio-sensitivity and tumor repopulation rate is important for the calculation of cell survival curves. Self-absorption of emitted radiation and dose enhancement due to AuNPs must be considered in the calculations. Selection of radionuclide for radioactive NP must consider size of tumor, repopulation rate and radiosensitivity of tumor cells. Au-198 NPs functionalized with Mangiferin are a suitable choice for treating large, radioresistant and rapidly growing tumors. (AU)

• FAPESP's process: 18/15598-2 - Tumor ablation using ionizing radiation and Pd and Au nanoparticles in Melanoma and Hepatocellular Carcinoma in vitro and in vivo
• Grantee: Lucas Freitas de Freitas
• Support Opportunities: Scholarships in Brazil - Post-Doctoral