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Item The prognostic value of mean apparent diffusion coefficient measured with diffusion-weighted magnetic resonance image in patients with prostate cancer treated with definitive radiotherapy(2022) Onal, Cem; Erbay, Gurcan; Guler, Ozan Cem; Oymak, Ezgi; 35753556Purpose: To assess the correlation between initial tumor apparent diffusion coefficient (ADC) values and clinicopathological parameters in prostate cancer (PCa) patients treated with definitive radiotherapy (RT). Additionally, the prognostic factors for freedom from biochemical failure (FFBF) and progressionfree survival (PFS) in this patient cohort were analyzed. Materials and methods: The clinical data of 503 patients with biopsy-confirmed PCa were evaluated retrospectively. All patients had clearly evident tumors on diffusion-weighted magnetic resonance imaging (DW-MRI) for ADC values. Univariable and multivariable analyses were used to determine prognostic factors for FFBF and PFS. Results: The median follow-up was 72.9 months. The 5-year FFBF and PFS rates were 93.2% and 86.2%, respectively. Significantly lower ADC values were found in patients with a high PSA level; advanced clinical stage; higher ISUP score, and higher risk group than their counterparts. Receiver operating characteristic (ROC) curve analysis revealed an ADC cut-off value of 0.737 x 10-3 mm2/sec for tumor recurrence. Patients who progressed had a lower mean ADC value than those who did not (0.712 +/- 0.158 vs. 1.365 +/- 0. 227 x 10-3 mm2/sec; p < 0.001). There was a significant difference in 5-year FFBF (96.3% vs. 90%; p < 0.001) and PFS rates (83.8% vs. 73.5%; p = 0.002) between patients with higher and lower mean ADC values. The FFBF and PFS were found to be correlated with tumor ADC value and ISUP grades in multivariable analysis. Additionally, older age was found to be a significant predictor of worse PFS. Conclusions: Lower ADC values were found in patients with high-risk characteristics such as a high serum PSA level, stage or grade of tumor, or high-risk disease, implying that ADC values could be used to predict prognosis. Lower ADC values and higher ISUP grades were associated with an increased risk of BF and progression, implying that treatment intensification may be required in these patients. (c) 2022 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 173 (2022) 285-291Item Half-dose bevacizumab experience in relapsed ovarian cancer patients in Turkey due to formal regulations: similar effectiveness with lower rate of hypertension(2020) Kose, Fatih; Alemdaroglu, Songul; Mertsoylu, Huseyin; Besen, Ali Ayberk; Guler, Ozan Cem; Simsek, Seda Yuksel; Erbay, Gurcan; Onal, Cem; Celik, Husnu; 0000-0003-4335-6659; 0000-0002-2742-9021; 0000-0001-6908-3412; 0000-0002-1706-8680; 0000-0002-0156-5973; 0000-0002-7862-0192; 0000-0002-1932-9784; 33099934; AAI-8400-2021; D-5195-2014; AAC-5654-2020; AAK-5370-2021; G-4827-2016; AAK-7016-2021; AAD-6910-2021; M-9530-2014Purpose: Ovarian cancer is the fifth leading cause of cancer related death in women. Platin-based doublet regimens plus bevacizumab is standard treatment in relapse. Due to formal regulation of Turkish Ministry of Health, adjuvant bevacizumab has not been reimbursed and clinicians can use bevacizumab at a dose of 7.5 mg/kg/3wk in platin-resistant and sensitive relapse settings. The primary aim of this study was to evaluate 7.5 mg/kg/3wk bevacizumab dosing in platin-resistant and sensitive relapse ovarian cancer and compare these findings with the current literature. Methods: A total of 106 patients with relapsed ovarian cancer and treated with bevacizumab (bevacizumab is not reimbursed as a part of adjuvant treatment in Turkey) on their first relapse were included. Results: At a median follow-up of 32.1 months (5.3-110.8), 56 (52.8%) patients died. Progression-free survival (PFS) and overall survival (OS) were estimated at 18.8 months (14.4-23.3) vs 29.7 months (24.3-35.1) of the whole group overall survival. We observed that 78.4% of patients treated with primary surgery without neoadjuvant treatment and 59 (57.8%) out of the 102 patients with debulking surgery relapsed. A significant number of patients (81%) treated with primary surgery without neoadjuvant treatment and 59 (76.6 %) had secondary debulking surgery at relapse. In relapse, 38 patients were treated with single agent liposomal doxorubicin (LPD) plus bevacizumab. On the other hand, 68 patients were treated with carboplatin and LPD plus bevacizumab. Multivariate analysis failed to show any clinicopathological characteristics with significant effect on PFS. However, cytoreductive surgery at relapse showed significant effect on OS. Bevacizumab-related toxicities were detected in 23 (21.7%) patients; hypertension, pulmonary embolism, perforation, and other toxicities (nephrotic syndrome in 2, osteonecrosis in 2, cerebrovascular and cardiac ischemia in 3 patients) were seen in 12 (11.3%), 3 (2.8%), 1 (0.9%) and 7 (6.6%) patients, respectively. Conclusions: In conclusion, our findings showed that 7.5 mg/ kg/3week dosing of bevacizumab in relapsed ovarian cancer could have similar effectiveness compared to standard 15 mg/ kg/3week dosing. Increase of OS and PFS in patients treated with primary and secondary debulking surgery with no-visible disease was more pronounced. No new safety information was observed but lower rate of grade 3 or above hypertension with similar rate of severe vascular and intestinal complications were detected.Item Prognostic values of ADC(mean) and SUVmax of the primary tumour in cervical cancer patients treated with definitive chemoradiotherapy(2019) Yildirim, Berna Akkus; Onal, Cem; Erbay, Gurcan; Guler, Ozan Cem; Karadeli, Elif; Reyhan, Mehmet; Koc, Zafer; 0000-0002-2742-9021; 0000-0003-0987-1980; 30354907; D-5195-2014; S-8384-2016We analysed the correlation of F-18-fluorodeoxyglucose uptake into primary tumours using the maximum standardised uptake value (SUVmax) and the mean apparent diffusion coefficient (ADC(mean)) values in magnetic resonance imaging (MRI) with the clinical and pathological factors in patients with cervical cancer who were treated with concurrent chemoradiotherapy. The patients were stratified according to the primary tumour pre-treatment ADC(mean) and SUVmax cut-off values. There were significant correlations between the SUVmax of the primary tumour and tumour size, and the treatment response. The correlation between the ADC(mean) and FIGO stage, tumour size, and the lymph node metastasis was significant. The SUVmax was significantly and inversely correlated with the ADC(mean) for cervical cancer (r = -0.44, p <.001). In the multivariate analysis, the primary tumour ADC(mean), treatment response and the lymph node metastasis emerged as significant independent predictors of both OS and DFS, and of the primary tumour SUVmax for DFS. Tumour size has a borderline significance for OS. High SUVmax and low ADC(mean) of the primary tumour are important predictive factors for identifying high-risk patients with cervical cancer who are treated with definitive chemoradiotherapy. These results point to a future role for the diffusion-weighted MRI and for F-18-fluorodeoxyglucose positron emission tomography, not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy for individual patients.Item A RARE COMPLICATION OF PERITONEAL DIALYSIS: ENCAPSULATED PERITONEAL SCLEROSIS(2019) Tekkarismaz, Nihan; Torun, Dilek; Ozelsancak, Ruya; Micozkadioglu, Hasan; Erbay, Gurcan