ESTRO 2025 - Abstract Book

S2119

Clinical - Urology

ESTRO 2025

Conclusion: Our study found patients with “High” hypoxia -scores have increased genomic instability, which mostly affected chromosomes 12, 14, 17 and 18. Altogether, our findings act as a proof-of-concept that hypoxia induces specific genomic alterations in bladder cancer. These findings pave the way to improve the application of hypoxia-modifying therapies, potentially enhancing therapeutic outcomes in bladder cancer management. Future work should aim to perform a deep in silico analysis of specific genomic mutations and their association with patient outcomes.

Keywords: CNVs, Hypoxia, Bladder Cancer, genome alteration

References: 1. Abou Khouzam R, The Effect of Hypoxia and Hypoxia-Associated Pathways in the Regulation of Antitumor Response: Friends or Foes? Front Immunol. 2022 Feb 8;13:828875. doi: 10.3389/fimmu.2022.828875. PMID: 35211123; PMCID: PMC8861358. 2. Bigos KJ, Quiles CG, Tumour response to hypoxia: understanding the hypoxic tumour microenvironment to improve treatment outcome in solid tumours. Front Oncol. 2024 Jan 30;14:1331355. doi: 10.3389/fonc.2024.1331355. PMID: 38352889; PMCID: PMC10861654. 3. Muz B, de la Puente P. The role of hypoxia in cancer progression, angiogenesis, metastasis, and resistance to therapy. Hypoxia (2015) 3:83. doi: 10.2147/HP.S93413

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Digital Poster The effectiveness of radiotherapy in patients with oligometastatic prostate cancer at initial diagnosis Gul Aysen Ozturk 1 , Meral Kurt 2 , Asma Daneshvar 2 , Oktay Çayırlı 2 , Murat Ozturk 3 , Anıl Erkan 3 , Kadir Omur Gunseren 4 1 Radiation oncology, Bursa City Hospital, Bursa, Turkey. 2 Radiation oncology, Uludag University, Bursa, Turkey. 3 Urology, Bursa Yuksek Ihtisas Training and Research Hospital, Bursa, Turkey. 4 Urology, Uludag University, Bursa, Turkey Purpose/Objective: To evaluate the effectiveness of radiotherapy in our patients with oligometastatic prostate cancer who had 1-5 lesions at diagnosis. Material/Methods: In our study, a total of 72 patients who were diagnosed with metastatic prostate cancer and received radiotherapy for both metastases and primary tumors between December 2010 and May 2022 in both centers were evaluated retrospectively. Results: The mean age of the 72 patients included in the study was 70.49 (49-85). The median PSA value was 100(11-1000) ng/ml, and the median Gleason score was 8 (6-10). While the metastatic site was only bone in 53 (73.6%) patients, 19 (26.4%) patients also had lymph node and solid organ metastases. The median primary radiotherapy (RT) dose was 33 (12-42) fraction (fx) and 72 (36-75.6) gray (Gy). The median follow-up period of the patients was 34 (33.6-48) months. 3 patients did not come for follow-up after RT. Orchiectomy was performed in 2 patients before radiotherapy, and maximal androgen blockade (MAB) was started in 70 patients. 17 (23.6%) patients received 2-6 cycles of chemotherapy (CT) before RT. In the statistical analysis, the mean progression-free survival(PFS) time of the patients was 35.1 months, while the mean overall survival (OS)time was 48.3 months. In our study, it was found that the dose applied to the prostate significantly increased progression-free survival. In patients with prostate doses of 70 Gy and above, PFS was mean 45.3 months, while in patients with doses below 70 Gy, PFS was found to be 24.1 months (p=0.003). When the effect