Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item Comparison of Helical and TomoDirect Techniques with Simultaneous Integrated Boost in Early Breast Cancer Patients(REPORTS OF PRACTICAL ONCOLOGY AND RADIOTHERAPY, 2023) Onal, Cem; Bozca, Recep; Oymak, Ezgi; Guler, Ozan CemBackground: The aim of the study was to perform dosimetric comparisons of helical (H) and TomoDirect (TD) plans for whole-breast irradiation (WBI) with simultaneous integrated boost (SIB) in early-stage breast cancer patients undergoing breast conserving surgery.Materials and methods: Fifty patients, 25 with left-side and 25 with right-side tumors, were determined for a treatment planning system for a total dose of 50.4Gy in 1.8Gy per fraction to WBI, with a SIB of 2.3Gy per fraction delivered to the tumor bed. The planning target volume (PTV) doses and the conformity (CI) and homogeneity indices (HI) for PTV(breast )and PTVboost, as well as organ-at-risk (OAR) doses and treatment times, were compared between the H and TD plans.Results: All plans met the PTV coverage criteria for the H plan, except for mean V107 of PTVbreast for TD plan. The H plan yielded better homogeneity and conformity of dose distribution compared to the TD plan. The ipsilateral mean lung doses were not significantly different between the two plans. The TD plans is advantageous for mean doses to the heart, contralateral breast and lung, spinal cord, and esophagus than the H plans. In both the H and TD plans, the right-sided breast patients had lower heart dose parameters than the left-sided breast patients. The TD plan is superior to the H plan in sparing the contralateral breast and lung by decreasing low-dose volumes.Conclusions: While the OAR dose advantages of TD are appealing, shorter treatment times or improved dose homogeneity and conformity for target volume may be advantageous for H plan.Item Innovations in Cervical Cancer Treatment-There is Still Room for Improvement(2023) Onal, Cem; Yavas, Guler; HOC-5611-2023; AAE-2822-2020Item Untitled Reply(2023) Onal, Cem; Sezen, Duygu; Oymak, Ezgi; Bolukbasi, YaseminItem In Regard to Boeri et al. 'Oligorecurrent Prostate Cancer Treated with Metastases-Directed Therapy or Standard of Care: A Single-Center Experience'(2023) Bolukbasi, Yasemin; Oymak, Ezgi; Durankus, Nilufer Kilic; Onal, Cem; https://orcid.org/0000-0002-2742-9021; 35027691; HOC-5611-2023Item Restaging of Cervical Cancer Patients Treated with Adjuvant Radiotherapy According to FIGO 2018 and Suggestions for the Next Staging: Turkish Society for Radiation Oncology Gynecologic Group Study (TROD 04-004)(2022) Alanyali, Senem; Balci, Beril; Esen, Caglayan Selenge Beduk; Gultekin, Melis; Yildirim, Berna Akkus; Ozkurt, Selnur; Ergen, Sefika Arzu; Gursel, Sukriye Bilge; Cetin, Ilknur Alsan; Sert, Fatma; Sari, Sezin Yuce; Ibis, Kamuran; Onal, Cem; Sahinler, Ismet; Yildiz, Ferah; Ozsaran, ZeynepOBJECTIVE The objective of this study was to compare Federation of Gynecology and Obstetrics (FIGO) 2009 and 2018 staging systems in patients with uterine cervical cancer. METHODS Medical records of 571 patients who were treated with adjuvant radiotherapy or radiochemotherapy between 2001 and 2018 were retrospectively reviewed. Differences in overall survival (OS) and progression-free survival (PFS) rates according to FIGO 2009 and FIGO 2018 staging systems were compared using the log-rank test. Cox regression model was used to identify independent prognostic factors for survival. RESULTS The median follow-up was 59 months. Five-year OS and PFS rates were 81.1% and 77.7%, respectively. Stage migration was recorded in 401 patients (70.2%) and the most remarkable stage migration was detected in stage I patients (60%). A total of 157 (27.5%) patients upstaged to stage IIIC disease. According to FIGO 2009, 5-year OS rates were 87.3%, 80.5% (p=0.076), and PFS rates were 82.8%, 77.5% (p=0.036) for stage IB1 and IB2, respectively. According to FIGO 2018, the 5-year OS rates for stage IB1, IB2, and IB3 were 89.8%, 87.1%, and 81.4% (p=0.310), and PFS rates were 90.2%, 80.5%, and 80.1% (p=0.189), respectively. Patients with >= 2 pelvic lymph node (LN) metastases had worse 5-year OS and PFS rates than patients with one metastasis (p=0.015 and p=0.006). Number of para-aortic LN metastasis and metastatic LN ratio (MLNR) were also correlated with 5-year OS and PFS. CONCLUSION Current FIGO staging system better discriminates patients with cervical cancer. However, integration of metastatic LN number and/or MLNR to the upcoming FIGO staging system may improve the prognostic value of the staging.Item Stereotactic Body Radiotherapy and Tyrosine Kinase Inhibitors in Patients with Oligometastatic Renal Cell Carcinoma: A Multi-Institutional Study(2023) Onal, Cem; Oymak, Ezgi; Guler, Ozan Cem; Tilki, Burak; Yavas, Guler; Hurmuz, Pervin; Yavas, Cagdas; Ozyigit, Gokhan; https://orcid.org/0000-0002-2742-9021; 36450836; HOC-5611-2023Purpose Few studies have determined the viability of stereotactic body radiotherapy (SBRT) and tyrosine kinase inhibitors (TKIs) in the treatment of metastatic renal cell carcinoma (mRCC). We examined the results of RCC patients who had five or fewer lesions and were treated with TKI and SBRT.Methods The clinical data of 42 patients with 96 metastases treated between 2011 and 2020 were retrospectively evaluated. The prognostic factors predicting overall survival (OS) and progression-free survival (PFS) were assessed in uni-and multivariable analyses.Results Median follow-up and time between TKI therapy and SBRT were 62.3 and 3.7 months, respectively. The 2-year OS and PFS rates were 58.0% and 51.3%, respectively, and 2-year local control rate was 94.1% per SBRT-treated lesion. In univariable analysis, the time between TKI therapy and SBRT and treatment response were significant prognostic factors for OS and PFS. In multivariable analysis, a time between TKI therapy and SBRT of less than 3 months and complete response were significant predictors of better OS and PFS. Only 12 patients (28.6%) had a systemic treatment change at a median of 18.2 months after SBRT, mostly in patients with a non-complete treatment response after this therapy. Two patients (4.8%) experienced grade III toxicity, and all side effects observed during metastasis-directed therapy subsided over time.Conclusion We demonstrated that SBRT in combination with TKIs is an effective and safe treatment option for RCC patients with <= 5 metastases. However, distant metastasis was observed in 60% of the patients, indicating that distant disease control still has room for improvement.Item Stereotactic Ablative Body Radiotherapy as a Bridge to Liver Transplant for Hepatocellular Carcinoma: Preliminary Results of Baskent University Experience(2022) Yavas, Guler; Soy, Ebru Hatice Ayvazoglu; Coskun, Mehmet; Onal, Cem; Boyvat, Fatih; Haberal, Mehmet; https://orcid.org/0000-0002-3462-7632; 35384806; HOC-5611-2023; AAJ-8097-2021Objectives: Hepatocellular carcinoma is the most common primary liver tumor, with curative treatment options being liver transplant and resection. However, approximately 20% to 30% of patients have substantial disease progression while awaiting transplant. Here, we report our initial experience on stereotactic ablative body radiotherapy as a bridge to liver transplant for patients with hepatocellular carcinoma. Materials and Methods: Seven patients with 9 lesions received stereotactic ablative body radiotherapy as a bridge treatment to transplant. All patients underwent radiofrequency ablation, transcatheter arterial chemoembolization, or hepatic resection before stereotactic ablative body radiotherapy. Magnetic resonance imaging was used to evaluate radiographic responses 1 month later. Results: Median age of patients was 65 years (range, 63-71 years), median stereotactic ablative body radiotherapy dose was 45 Gy (range, 30-54 Gy; delivered in 3-5 fractions), and median tumor diameter was 17 mm (range, 12-30 mm). Before stereotactic ablative body radiotherapy, all patients underwent liver-directed therapies, including transcatheter arterial chemoembolization for 3 lesions, transcatheter arterial chemoembolization and radiofrequency ablation for 4 lesions, surgical resection for 1 lesion, and surgical resection plus transcatheter arterial chemoembolization for the remaining lesion. Patients showed no evidence of gastrointestinal toxicity or radiation-induced liver disease. Acute toxicity was negligible; all patients completed the treatment course. One month after stereotactic ablative body radiotherapy administration, response rates were assessed with magnetic resonance imaging, with complete responses obtained in 5 lesions (55.5%), partial responses for 2 lesions, and stable disease for 2 lesions. No disease progression was shown following stereotactic ablative body radiotherapy application. Conclusions: Stereotactic ablative body radiotherapy is an effective, safe, and tolerable bridging therapy option. Although we observed an early response after treatment, exact response rates will not be known for at least 3 months following stereotactic ablative body radiotherapy. Thus, our findings should be confirmed through additional prospective studies with longer follow-up.Item Neoadjuvant Prostate SBRT Followed by Prostatectomy(2022) Onal, Cem; Sezen, Duygu; Oymak, Ezgi; Bolukbasi, Yasemin; 0000-0002-2742-9021; D-5195-2014Item 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.