ESTRO 2024 - Abstract Book

S317

Brachytherapy - Head & neck, skin, eye

ESTRO 2024

Z/A ratio of one, compared to around 0.5 for the other elements, giving hydrogen nearly twice the stopping power of the other elements when confronted with an energetic electron (5). Hydrogen gas has not been shown to be bio-toxic in investigations, and the maximum allowable concentration of 4% was employed in this study due to flammability concerns (6). The presence of H2-NBs in melanoma tumor tissue, according to this study, can increase the dose by up to 300%, significantly reducing the duration of the plaque on the human eye. Some of the possible benefits of employing H2-NBs include minimizing plaque implantation time on the patient's eye, reducing sclera-absorbed dose, and reducing the danger of patients' vital organ irradiation. The specially constructed phantom may be used for commissioning and quality control of 106Ru ocular plaques, as well as for ophthalmic research, with various host materials as tumors and nanoparticles/bubbles as dose enhancers. The results were recently published in the Medical Physics Journal (7).

Keywords: Ocular Melanoma, Ru-106 Plaque, Nanobubbles

References:

1. Michailidi ED, Bomis G, Varoutoglou A, Efthimiadou EK, Mitropoulos AC, Favvas EP. Fundamentals and applications of nanobubbles. InInterface science and technology 2019 Jan 1 (Vol. 30, pp. 69-99). Elsevier.

2. Prabhakar A, Banerjee R. Nanobubble liposome complexes for diagnostic imaging and ultrasound-triggered drug delivery in cancers: a theranostic approach. ACS omega. 2019 Sep 12;4(13):15567-80.

3. Singh AD, Turell ME, Topham AK. Uveal melanoma: trends in incidence, treatment, and survival. Ophthalmology. 2011 Sep 1;118(9):1881-5.

4. Shields CL, Shields JA. Ocular melanoma: relatively rare but requiring respect. Clinics in dermatology. 2009 Jan 1;27(1):122-33.

5. Pages L, Bertel E, Joffre H, Sklavenitis L. Energy loss, range, and bremsstrahlung yield for 10-keV to 100-MeV electrons in various elements and chemical compounds. Atomic Data and Nuclear Data Tables. 1972 Mar 1;4:1 27.

6. Li S, Liao R, Sheng X, Luo X, Zhang X, Wen X, Zhou J, Peng K. Hydrogen gas in cancer treatment. Frontiers in oncology. 2019:696.

7. Hashemi S, Aghamiri SM, Siavashpour Z, Kahani M, Zaidi H, Jaberi R. Hydrogen nanobubbles: A novel approach toward radio ‐ sensitization agents. Medical Physics. 2023 Jun 6.

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Digital Poster

The evolving landscape of head-and-neck brachytherapy (2017-2023): a scoping review

Marjorie Mae Cua 1,2 , Carl Jay Jainar 3 , Janella Ann Javenrie Calapit 1 , Michael Benedict Mejia 3 , Warren Bacorro 3,2,4

1 Cardinal Santos Medical Center, Department of Radiation Oncology, San Juan, Philippines. 2 Manila Doctors Hospital, Department of Radiation Oncology, Manila, Philippines. 3 University of Santo Tomas Hospital – Benavides Cancer Institute, Department of Radiation Oncology, Manila, Philippines. 4 University of Santo Tomas – Faculty of Medicine and Surgery, Department of Clinical Epidemiology, Manila, Philippines