Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item Prostate Mucinous Carcinoma Treated with Definitive Radiotherapy and Hormonal Therapy: Case Report and Review of the Literature(2014) Guler, Ozan Cem; Onal, Cem; Erbay, Gurcan; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0002-1706-8680; 24365124; AAC-5654-2020; HOC-5611-2023; AAK-5370-2021Prostate mucinous carcinoma (MC) is a rare variant of prostate adenocarcinoma that is characterized by large pools of extracellular mucin, which by definition compose at least 25% of the tumor volume. Prostate MC has 3 subtypes. The most common variant is pure MC; primary signet ring cell carcinoma and MC with signet ring cell are less common variants and are more aggressive than pure MC. Because of the rarity of prostate MC and conflicting reports regarding the behavior of the disease, the optimal treatment strategy is not clear. Most series report the efficacy of surgery. We report a rare case of a patient with a large prostate MC that was treated successfully with hormone therapy (HT) and radiotherapy (RT). Treatment response was assessed by dynamic contrast-enhanced magnetic resonance imaging (MRI). (C) 2014 Elsevier Inc. All rights reserved.Item Treatment Outcomes of Breast Cancer Liver Metastasis Treated with Stereotactic Body Radiotherapy(2018) Onal, Cem; Guler, Ozan Cem; Yildirim, Berna Akkus; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0001-6661-4185; 30296648; HOC-5611-2023; AAC-5654-2020; V-5717-2017Background: To assess the outcomes of breast cancer liver metastasis (BCLM) treated with stereotactic body radiotherapy (SBRT) and systemic treatment. Materials and methods: Patients with oligometastasis at the time of liver metastasis (LM) or who became oligometastatic (<= 5 metastases) after systemic treatment were assessed. Twenty-nine liver metastatic lesions were treated with a total of 54 Gy delivered in 3 fractions. The local control (LC), overall survival (OS), and progression-free survival (PFS) rates were calculated using Kaplan-Meier analyses. Results: A total of 22 patients with 29 liver metastatic lesions treated with liver SBRT between April 2013 and September 2017 were retrospectively analyzed. After a median follow-up time of 16.0 months (range 4.4-59.4 months), 18 patients (82%) had disease recurrence, median of 7.4 months (range 1.0-27.9 months) after completion of liver SBRT. The 1- and 2-year OS rates were 85% and 57%, and the 1- and 2-year PFS rates were 38% and 8%, respectively. The 1- and 2-year LC rates were 100% and 88%, respectively. No significant prognostic factors, including disease extension, size of metastasis, number of liver metastasis and timing of liver metastasis, hormonal status affecting OS, PFS and LC were found. No patients experienced Grade 4 or 5 toxicity; furthermore, only one patient experienced rib fracture 6 months after completion of treatment, and one patient had a duodenal ulcer. Conclusion: This study is the first to evaluate the feasibility of SBRT to BCLM patients. Liver SBRT is a conservative approach with excellent LC and limited toxicities. (C) 2018 Elsevier Ltd. All rights reserved.Item Graves' Ophthalmopathy Treated with Protracted Hypofractionated Low-Dose Adaptive Radiotherapy: Case Report and Review of The Literature(2016) Guler, Ozan Cem; Onal, Cem; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-2742-9021; 26466836; AAC-5654-2020; HOC-5611-2023Graves' ophthalmopathy (GO) is the most common extra-thyroidal manifestation of Graves' disease. The treatment options for GO are high-dose glucocorticoids, selenium, rituximab, cyclosporine, orbital radiotherapy (RT), and surgery. A 43-year-old male patient was referred to our clinic with complaints of severe bilateral proptosis, diplopia, and orbital pain at both globes for 1 year. Pretreatment magnetic resonance imaging revealed bilateral proptosis, the expansion of bilateral optic nerves sheath, the increase of right medial muscle thickness, and a mass at the right eyehole. Patient was treated with 1 Gy per fraction per week with a total dose of 10 Gy over 10 weeks with adoptive intensity-modulated radiotherapy technique. During RT at 3rd and 6th weeks, a moderate shrinkage of the lesions was observed. The patient has been disease free, has had no complaints for 36 months, and has not required any surgical intervention. No late side effects such as retinopathy or cataract were observed. Orbital RT with innovative techniques may be considered as an initial local treatment for GO. With adoptive protracted low dose RT, a good clinical and radiological response could be seen without increasing early and late reactions.Item Metachronous Prostate Metastasis of Renal Cell Carcinoma: Case Report and Review of the Literature(2016) Guler, Ozan Cem; Bal, Nebil; Onal, Cem; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-2742-9021; 26739102; AAC-5654-2020; HOC-5611-2023Secondary tumors of the prostate are very rare, and only a few reports of prostate metastasis originating from renal cell carcinoma (RCC) have been published. The reported 5-year survival rate has been approximately 35% for patients who underwent nephrectomy and surgical resection of a solitary metastasis. Immunohistochemical analysis showed that CD10 and vimentin positivity were helpful for distinguishing clear cell RCC from other renal tumors. We report a case with delayed metachronous metastasis of RCC to the prostate, which clinically mimicked benign prostatic hyperplasia or prostate cancer, treated with transurethral resection and palliative radiotherapy. (C) 2016 Elsevier Inc. All rights reserved.Item Prognostic Significance Of Albumin And Globulin Levels In Cervical Cancer Patients Treated With Chemoradiotherapy(2023) Oymak, Ezgi; Guler, Ozan Cem; Onal, Cem; https://orcid.org/0000-0002-2742-9021; 36356983; D-5195-2014ObjectiveAlbumin-globulin ratio or albumin-globulin score predict survival in many cancers, but there are few data on cervical cancer patients. This study examined whether pre-treatment albumin and globulin levels, as well as the albumin-globulin ratio and albumin-globulin score, can predict treatment outcomes in cervical cancer patients undergoing definitive chemoradiotherapy. MethodsA retrospective analysis of cervical cancer patients treated between January 2006 and July 2014 was performed. Receiver operating characteristic curves for serum albumin and globulin levels, as well as albumin-globulin ratio values, were generated in order to determine the cut-off values for these parameters and to predict their sensitivity and specificity for predicting recurrence and survival. Univariate and multivariate analyses were used to identify prognostic factors for overall survival and progression-free survival. ResultsA total of 139 patients were included. The median follow-up time was 11.5 years. The 5- and 10-year overall survival rates were 54.7% and 39.3%, while the 5- and 10-year progression-free survival rates were 48.9% and 36.4%, respectively. The optimal cut-off points were 3.79 g/dL for albumin, 3.27 g/dL for globulin, and 1.56 for albumin-globulin ratio. In the univariate analysis, significant prognostic factors for overall survival and progression-free survival were albumin-globulin ratio, albumin-globulin score, patient age, International Federation of Gynecology and Obstetrics (FIGO) stage, tumor size, lymph node metastasis, and treatment response. Older age, advanced stage, low albumin-globulin ratio, albumin-globulin score of 2, and inadequate treatment response had poor overall survival and progression-free survival in multivariable analysis. However, serum albumin and globulin levels were not found to be a significantly predictive factor for survival. There was a significant correlation between albumin levels, globulin levels, tumor size, stage, lymph node metastasis, and treatment response. ConclusionsPre-treatment albumin-globulin ratio and albumin-globulin score are useful prognostic factors in patients with cervical squamous cell cancer treated with definitive chemoradiotherapy, and may be suitable biomarkers for predicting treatment outcomes.Item Treatment Outcomes of Stereotactic Body Radiotherapy in Patients with Synchronous and Metachronous Oligometastatic Renal Cell Carcinoma(2023) Guler, Ozan Cem; Oymak, Ezgi; Hurmuz, Pervin; Yavas, Guler; Tilki, Burak; Yavas, Cagdas; Ozyigit, Gokhan; Onal, Cem; 0000-0002-2742-9021; 36455527; D-5195-2014Introduction: The aim of this study was to investigate the clinical outcomes of metastasis-directed therapy (MDT) using stereotactic body radiotherapy (SBRT) in patients with synchronous or metachronous oligometastatic renal cell carcinoma (RCC). Methods: The clinical data of 87 patients with 138 lesions who received MDT between February 2008 and January 2019 were retrospectively analyzed. All patients had <= 5 metastasis at diagnosis (synchronous) or during progression (metachronous) and were treated with SBRT for their metastasis. The primary endpoints were local control (LC) and progression-free survival (PFS). The secondary endpoint was overall survival (OS). Results: Median follow-up was 20.4 months for entire cohort and 27.2 months for survivors. Synchronous oligometastatic disease was observed in 35 patients (40.2%), and 52 patients (59.8%) had metachronous disease. Seventy-two patients (82.8%) received systemic treatment synchronously or after MDT, while 15 patients (17.2%) did not receive any systemic treatment. The 1- and 2-year OS rates were 79.4% and 58.1%, respectively, and the 1- and 2-year PFS rates were 58.6% and 15.1%, respectively. The 1- and 2-year LC rates per lesion were 96.6% and 91.4%, respectively. There were no significant differences in survival between patients with synchronous oligometastasis and those with metachronous oligometastasis. All disease progressions were observed at a median time of 31.6 months (range: 1.9-196.9 months) after the completion of SBRT. Patients with solitary oligometastasis had significantly better OS compared to patients with >1 metastasis (p = 0.04). No patients experienced grade 3 or higher acute or late toxicities. Conclusion: SBRT is a successful treatment for oligometastatic RCC patients due to its excellent LC and minimal toxicity profile. There were no statistically significant survival differences between patients with synchronous and metachronous oligometastasis. Patients with solitary oligometastasis outlived their counterparts.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 Bone Only Oligometastatic Renal Cell Carcinoma Patients Treated with Stereotactic Body Radiotherapy: A Multi Institutional Study(2022) Onal, Cem; Guler, Ozan Cem; Hurmuz, Pervin; Yavas, Guler; Tilki, Burak; Oymak, Ezgi; Yavas, Cagdas; Ozyigit, Gokhan; 0000-0002-2742-9021; 35695908; D-5195-2014Purpose This study aimed to analyze the prognostic factors associated with overall survival (OS) and progression-free survival (PFS) in patients with bone-only metastatic renal cell carcinoma (RCC) who have five or fewer lesions treated with stereotactic body radiotherapy (SBRT). Methods The clinical data of 54 patients with 70 bone metastases undergoing SBRT treated between 2013 and 2020 with a dose of at least 5 Gy per fraction and a biologically effective dose (BED) of at least 90 Gy were retrospectively evaluated. Results The majority of lesions were located in the spine (57.4%) and had only one metastasis (64.8%). After a median follow-up of 22.4 months, the 1- and 2-year OS rates were 84.6% and 67.3%, respectively, and median OS was 43.1 months. The 1- and 2-year PFS rates and median PFS were 63.0%, 38.9%, and 15.3 months, respectively. In SBRT-treated lesions, the 1-year local control (LC) rate was 94.9%. Age, metastasis localization, and number of fractions of SBRT were significant prognostic factors for OS in univariate analysis. In multivariate analysis, patients with spinal metastasis had better OS compared to their counterparts, and patients who received single-fraction SBRT had better PFS than those who did not. No patient experienced acute or late toxicities of grade 3 or greater. Conclusion Despite excellent LC at the oligometastatic site treated with SBRT, disease progression was observed in nearly half of patients 13 months after metastasis-directed local therapy, particularly as distant disease progression other than the treated lesion, necessitating an effective systemic treatment to improve treatment outcomes.Item The Role Of Stereotactic Body Radiotherapy In Switching Systemic Therapy For Patients With Extracranial Oligometastatic Renal Cell Carcinoma(2022) Onal, Cem; Hurmuz, Pervin; Guler, Ozan Cem; Yavas, Guler; Tilki, Burak; Oymak, Ezgi; Yavas, Cagdas; Ozyigit, Gokhan; https://orcid.org/0000-0002-2742-9021; 35119653; D-5195-2014Background Targeting oligometastatic lesions with metastasis-directed therapy (MDT) using stereotactic-body radiotherapy (SBRT) may improve treatment outcomes and postpone the need for second-line systemic therapy (NEST). We looked at the results of oligometastatic renal cell carcinoma (RCC) patients who had five or fewer lesions and were treated with SBRT. Methods We examined the treatment outcomes of 70 extracranial metastatic RCC (mRCC) patients treated at two oncology centers between 2011 and 2020. The clinical parameters of patients with and without NEST changes were compared. The prognostic factors for overall survival (OS), progression-free survival (PFS), and NEST-free survival were evaluated. Results Median age was 67 years (range 31-83 years). Lung and bone metastasis were found in 78.4% and 12.6% of patients, respectively. With a median follow-up of 21.1 months, median OS was 49.1 months and the median PFS was 18.3 months. Histology was a prognostic factor for OS, BED, and treatment switch for PFS in univariate analysis. In multivariate analysis, the significant predictor of poor OS was clear cell histology, and a lower BED for PFS. Following SBRT for oligometastatic lesions, 19 patients (27.2%) had a median NEST change of 15.2 months after MDT completion. There were no significant differences in median OS or PFS between patients who had NEST changes and those who did not. No patient experienced grade >= 3 acute and late toxicities. Conclusions The SBRT to oligometastatic sites is an effective and safe treatment option for <= 5 metastases in RCC patients by providing favorable survival and delaying NEST change.Item National Multi-Center Observational Retrospective Study to Understand Treatment Patterns and Outcomes for Stage III Non-Small Cell Lung Cancer Patients in Turkey: Turkish Society for Radiation Oncology Study, STONE Trial(2022) Onal, Cem; Demiral, Ayse Nur; Atalar, Banu; Yalman, Deniz; Dagoglu, Nergiz; Hurmuz, Pervin; Erpolat, Petek; Akyurek, Serap; Gul, Sute Karabulut; Berber, Tanju; Guler, Ozan Cem; Umay, Cenk; Sert, Fatma; Karahacioglu, Eray; Birgi, Sumerya Duru; Yaprak, Gokhan; Saglam, Esra KaytanThis study investigated treatment patterns and outcomes in patients with inoperable stage III non-small cell lung cancer (NSCLC) treated with radiotherapy (RT) in Turkey. We included 492 patients with stage III NSCLC in this multi-center retrospective study. Pa-tient demographics, clinical characteristics, and clinical treatment patterns from the time of the initial diagnosis to disease progression were recorded. Additionally, the prognostic factors predicting overall survival (OS) and progression-free survival (PFS) were analyzed. For the initial treatment, 429 patients (89.2%) received chemotherapy and RT, whereas 53 patients (10.8%) were treated only with RT. The first disease progression occurred in 288 patients (58.4%) at 9.3 months (median) after the initial treatment, and 64.6% re-ceived treatment after first progression. The second disease progression occurred in 30 patients, and 20 patients (66.7%) received treatment. Median OS and PFS were 27.0 months and 13.4 months, respectively. Age (p< 0.001), stage (p= 0.04), poor performance score (PS) (p= 0.03) and RT doses (p= 0.002) were independent predictors for OS and PFS in our multivariate analysis. Additional significant predictors for OS in the multivariate analysis were gender (p= 0.004), treatment period (0.02), and irradiation technique (p= 0.02). Disease progression occurred in nearly 58% of the patients, and one-third of these patients remained untreated during the disease progression. These findings indicate a need for additional treatment options in patients with unresectable stage III NSCLC with high-risk features, namely older age, stage IIIB disease, poor PS, and lower RT doses.