1
|
Tegaw EM, Geraily G, Etesami SM, Ghanbari H, Gholami S, Shojaei M, Farzin M, Tadesse GF. Dosimetric effect of nanoparticles in the breast cancer treatment using INTRABEAM ®system with spherical applicators in the presence of tissue heterogeneities: A Monte Carlo study. Biomed Phys Eng Express 2021; 7. [PMID: 33836513 DOI: 10.1088/2057-1976/abf6a9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/09/2021] [Indexed: 02/07/2023]
Abstract
Using the 50 kV INTRABEAM®IORT system after breast-conserving surgery: tumor recurrence and organs at risk (OARs), such as the lung and heart, long-term complications remain the challenging problems for breast cancer patients. So, the objective of this study was to address these two problems with the help of high atomic number nanoparticles (NPs). A Monte Carlo (MC) Simulation type EGSnrc C++ class library (egspp) with its Easy particle propagation (Epp) user code was used. The simulation was validated against the measured depth dose data found in our previous study (Tegaw,et al2020 Dosimetric characteristics of the INTRABEAM®system with spherical applicators in the presence of air gaps and tissue heterogeneities,Radiat. Environ. Biophys. (10.1007/s00411-020-00835-0)) using the gamma index and passed 2%/2 mm acceptance criteria in the gamma analysis. Gold (Au) NPs were selected after comparing Dose Enhancement Ratios (DERs) of bismuth (Bi), Au, and platinum (Pt) NPs which were calculated from the simulated results. As a result, 0.02, 0.2, 2, 10, and 20 mg-Au/g-breast tissue were used throughout this study. These particles were not distributed in discrete but in a uniform concentration. For 20 mg-Au/g-breast tissue, the DERs were 3.6, 0.420, and 0.323 for breast tissue, lung, heart, respectively, using the 1.5 cm-diameter applicator (AP) and 3.61, 0.428, and 0.335 forbreast tissue, lung, and heart using the 5 cm-diameter applicator, respectively. DER increased with the decrease in the depth of tissues and increase in the effective atomic number (Zeff) and concentration of Au NPs, however, there was no significant change as AP sizes increased. Therefore, Au NPs showed dual advantages such as dose enhancement within the tumor bed and reduction in the OARs (heart and lung).
Collapse
Affiliation(s)
- Eyachew Misganew Tegaw
- Department of Physics, Faculty of Natural and Computational Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Ghazale Geraily
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Mohsen Etesami
- School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
| | - Hossein Ghanbari
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Somayeh Gholami
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Shojaei
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mostafa Farzin
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Getu Ferenji Tadesse
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Department of Physics, College of Natural and Computational Sciences, Aksum University, Ethiopia
| |
Collapse
|
2
|
Tegaw EM, Gholami S, Omyan G, Geraily G. Dosimetric characteristics of the INTRABEAM ® system with spherical applicators in the presence of air gaps and tissue heterogeneities. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2020; 59:295-306. [PMID: 32236740 DOI: 10.1007/s00411-020-00835-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 02/24/2020] [Indexed: 06/11/2023]
Abstract
The main aim of this study was to investigate the dosimetric characteristics of the INTRABEAM ® system in the presence of air gaps between the surface of applicators (APs) and tumor bed. Additionally, the effect of tissue heterogeneities was another focus. Investigating the dosimetric characteristics of the INTRABEAM® system is essential to deliver the required dose to the tumor bed correctly and reduce the delivered dose to the ribs and lung. Choosing the correct AP size and fitting it to the lumpectomy cavity is essential to remove the effect of air gaps and avoid inaccurate dose delivery. Consequently, the Geant4 toolkit was used to simulate the INTRABEAM ® system with spherical APs of various sizes. The wall effect of the ion chamber (IC) PTW 34013 used in the present study was checked. The simulations were validated in comparison with measurements, and then used to calculate any inaccuracies in dose delivery in the presence of 4- and 10-mm air gaps between the surface of the APs and the tumor bed. Also, the doses received due to tissue heterogeneities were characterized. It turned out that measurements and simulations were approximately in agreement (± 2%) for all sizes of APs. The perturbation factor introduced by the IC due to differences in graphite-coated polyethylene and air as compared to the phantom material was approximately equal to one for all AP. The greatest relative dose delivery difference was observed for an AP with a diameter of 1.5 cm, i.e., 44% and 70% in the presence of 4- and 10-mm air gaps, respectively. In contrast, the lowest relative dose delivery difference was observed for an AP with a diameter of 5 cm, i.e., 24% and 42% in the presence of 4- and 10-mm air gaps, respectively. Increasing APs size showed a decrease in relative dose delivery difference due to the presence of air gaps. In addition, the undesired dose received by the ribs turned out to be higher when a treatment site closer to the ribs was assumed. The undesired dose received by the ribs increased as the AP size increased. The lung dose turned out to be decreased due to the shielding effect of the ribs, small lung density, and long separation distance from the AP surface.
Collapse
Affiliation(s)
- Eyachew Misganew Tegaw
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, International Campus (TUMS-IC), Tehran, Iran
- Department of Physics, Faculty of Natural and Computational Sciences, Debre Tabor University, Debre Tabor, Ethiopia
| | - Somayeh Gholami
- Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran.
- The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34151, Trieste, Italy.
| | - Gilnaz Omyan
- Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran
- Department of Physics, Faculty of Sciences, University of Guilan, Rasht, Iran
| | - Ghazale Geraily
- Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|