Monte Carlo Comparison of Dose Distribution from Iodine-125 and Palladium-103 Isotopes in Plaque Brachytherapy for Ocular Melanoma Treatment

Document Type : Original Article

Authors

1 Department of Physics, University of Damghan, Damghan, Iran

2 Agricultural, Medical and Industrial Research, Nuclear Science and Technology Research Institute Karaj, Iran

3 Radiation Application Research Institute, Atomic Energy Organization of Iran, Tehran, Iran

10.22052/rsm.2026.258262.1162

Abstract

Eye plaques containing gamma-emitting radioactive sources are widely used in brachytherapy for the treatment of ocular melanoma. In this therapeutic approach, accurate dose distribution plays a crucial role in improving treatment effectiveness while minimizing the radiation dose delivered to the surrounding healthy tissues. In the present study, the three-dimensional dose distribution of the COMS eye plaque for the radionuclides Iodine-125 and Palladium-103 was investigated using Monte Carlo simulation, and the obtained results were compared with previously published data. All calculations were performed based on the TG-43 formalism recommended by the American Association of Physicists in Medicine. Simulations were carried out using the MCNPX and Geant4 codes while considering a heterogeneous human eye phantom. The results showed that the maximum absorbed dose within the tumor volume was approximately 91.2 Gy for Palladium-103 and 91.8 Gy for Iodine-125. Comparison of the results with previous TG-43-based studies demonstrated good agreement, with relative differences below 5% and statistical uncertainties less than 2%. Therefore, both radionuclides are capable of providing an appropriate dose distribution within the tumor volume, and the observed differences remain within the range of computational uncertainty. Consequently, the selection of an appropriate radionuclide should be based on clinical considerations, including tumor size, tumor location, and treatment planning objectives.

Keywords

References

  1. G.N. Thomas, I.-L. Chou, L. Gopal. Plaque radiotherapy for ocular melanoma. Cancers 16 (19) (2024) 3386.
  2. M. Laoues, R. Khelifi, A. Sidimoussa. Comparison between beta radiation dose distribution due to LDR and HDR ocular brachytherapy applicators using GATE Monte Carlo platform. Phys. Med. 32 (8) (2016) 1007-1018.
  3. H. Miras Del Río, A. Ortiz Lora, A. Bertolet Reina, J. A. Terrón León. A Monte Carlo dose calculation system for ophthalmic brachytherapy based on a realistic eye model. Med. Phys. 48 (8) (2021) 4542-4559.
  4. M. Lesperance, M. Martinov, R. M. Thomson. Monte Carlo dosimetry for 103Pd, 125I, and 131Cs ocular brachytherapy with various plaque models using an eye phantom. Med. Phys. 41 (3) (2014) 031706.
  5. K. Bilmin, K. J. Synoradzki, A. M. Czarnecka, M. J. Spałek, T. Kujawska, M. Solnik, P. Merks, M. D. Toro, R. Rejdak, M. Fiedorowicz. New perspectives for eye-sparing treatment strategies in primary uveal melanoma. Cancers 14 (1) (2022) 134.
  6. M. J. Rivard, B. M. Coursey, L. A. DeWerd, W. F. Hanson, M. S. Huq, G. S. Ibbott, M. G. Mitch, R. Nath, J. F. Williamson. Update of AAPM Task Group No. 43 Report: A revised AAPM protocol for brachytherapy dose calculations. Med. Phys. 31 (3) (2004) 633-674.
  7. J. Dolan, Z. Li, J. F. Williamson. Monte Carlo and experimental dosimetry of an 125I brachytherapy seed. Med. Phys. 33 (12) (2006) 4675-4684.
  8. J. I. Monroe, J. F. Williamson. Monte Carlo-aided dosimetry of the Theragenics TheraSeed model 200 103Pd interstitial brachytherapy seed. Med. Phys. 29 (4) (2002) 609-621.
  9. S. Asadi, M. Vaez-Zadeh, M. Vahidian, M. Marghchouei, S. F. Masoudi. Ocular brachytherapy dosimetry for 103Pd and 125I in the presence of gold nanoparticles: A Monte Carlo study. J. Appl. Clin. Med. Phys. 17 (3) (2016) 90-99.
  10. Y. C. Lee, S.-C. Lin, Y. Kim. Optic disc dose comparison between 125I and 103Pd Collaborative Ocular Melanoma Study (COMS) plaques based on current clinical practice. Cureus 13 (6) (2021) e15980.
  11. A. S. Meigooni, S. A. Dini, S. B. Awan, K. Dou, R. A. Koona. Theoretical and experimental determination of dosimetric characteristics for ADVANTAGE Pd-103 brachytherapy source. Appl. Radiat. Isot. 64 (8) (2006) 881-887.
  12. International Commission on Radiation Units and Measurements. Photon, Electron, Proton and Neutron Interaction Data for Body Tissues. ICRU Report 46, ICRU, Bethesda, MD, USA, 1992.
  13. H. Poorbaygi, E. Sardari, S. M. R. Aghamiri, S. Sheibani, M. Arjmand, S. Moradi, F. Ghassemi. Evolution of dose distribution for a 125I eye plaque using MCNPX and Plaque Simulator software. Precision Radiation Oncology 8 (2) (2024) 70-76.
  14. R. M. Thomson, R. E. P. Taylor, D. W. O. Rogers. Monte Carlo dosimetry for 125I and 103Pd eye plaque brachytherapy. Med. Phys. 35 (12) (2008) 5530-5543.
  15. A. A. Sonzogni. NuDat 2.0: Nuclear structure and decay data on the Internet. In: R. C. Haight, M. B. Chadwick, T. Kawano, P. Talou, (Eds.), International Conference on Nuclear Data for Science and Technology, AIP Conference Proceedings 769, Part 1. AIP, Melville, NY, USA (2005) 574-577.
  16. H. Cember, T. E. Johnson. Introduction to Health Physics. 4th ed. McGraw-Hill Medical, New York, USA, 2009.
  17. P. T. Finger, D. Zhou, N. Kalach, E. Semenova, W. Choi. 103Pd versus 125I ophthalmic plaque brachytherapy: Preoperative comparative radiation dosimetry for 319 uveal melanomas. J. Radiat. Oncol. 3 (4) (2014) 409-416.
  18. S.T. Chiu-Tsao, M. A. Astrahan, P. T. Finger, D. S. Followill, A. S. Meigooni, C. S. Melhus, F. Mourtada, M. E. Napolitano, R. Nath, M. J. Rivard, D. W. O. Rogers, R. M. Thomson. Dosimetry of 125I and 103Pd COMS eye plaques for intraocular tumors: Report of Task Group 129 by the AAPM and ABS. Med. Phys. 39 (10) (2012) 6161-6184.
  19. P. Ahmadia, R. Gilib. Comparative GEANT4-based Monte Carlo dosimetry of I-125 and Pd-103 in soft tissue, blood, and adipose tissue. Radiat. Phys. Eng. 7 (1) (2026) 1.

Files

Share

How to cite

Statistics