ESTRO 2024 - Abstract Book

S5295 ESTRO 2024 In our rat model, ACE inhibition using Captopril prevents fibrosis in and remodelling of the LV, improving cardiac function after heart irradiation, but only if the lung is spared. No protective effect of Captopril was observed if the lung and heart were irradiated. This may explain the inconclusive outcomes of clinical studies using Captopril but not considering heart dose. In addition, it suggests that using ACE inhibitors to reduce cardiopulmonary side effects requires careful patient selection and adapted treatment planning. Radiobiology - Normal tissue radiobiology

Keywords: cardiopulmonary, interaction, intervention

References:

(1) Ghobadi, G. et al. Physiological interaction of heart and lung in thoracic irradiation. Int J Radiat Oncol Biol Phys 84, e639–e646 (2012).

(2) Van Der Veen, S. J. et al. ACE inhibition attenuates radiation-induced cardiopulmonary damage. Radiotherapy and Oncology 114, 96–103 (2015).

(3) Small, W. et al. Utility of the ACE inhibitor captopril in mitigating radiation- associated pulmonary toxicity in lung cancer: Results from NRG Oncology RTOG 0123. Am J Clin Oncol 41, 396–401 (2018).

(4) Bracci, S. et al. Renin-Angiotensin System Inhibitors Might Help to Reduce the Development of Symptomatic Radiation Pneumonitis after Stereotactic Body Radiotherapy for Lung Cancer. Clin Lung Cancer 17, 189–197 (2016).

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Digital Poster

Oxytocin protects the brain from radiation-induced neurotoxicity, a result shown in MR spectroscopy

Ozum Atasoy 1 , Nilsu Cini 1 , Gokhan Yaprak 1 , Yigit Uyanıkgil 2 , Bahattin Ozkul 3 , Oytun Erbaş 4

1 Kartal Dr. Lutfi Kirdar City Hospital, Radiation Oncology, Istanbul, Turkey. 2 Ege University, Histology and Embryology, Izmir, Turkey. 3 Atlas University, Radiology, Istanbul, Turkey. 4 Demiroglu Bilim University, Physiology, Istanbul, Turkey

Purpose/Objective:

Neurocognitive impairment due to radiation-induced damage to healthy brain tissue is one of the significant side effects of treatment. The neuroprotective effects of oxytocin have been demonstrated in various neurotoxicity models previously. In our study, we aimed to demonstrate the potential protective effects of oxytocin in a radiation-induced neurotoxicity model.

Material/Methods:

In the study, 36 female Wistar albino rats were used. Drug administration (saline or oxytocin) began on the 1st day of the study and continued intraperitoneally for 21 days. On the 7th day of drug administration, computerized tomography simulation was performed, and a single fraction of 20 Gy radiotherapy was applied to the entire brain target volume (Figure 1). Behavioral tests were conducted on days 22-25 of the study, and magnetic resonance