PubMed İndeksli Yayınlar Koleksiyonu
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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 Oncological Outcomes For Encapsulated Papillary Carcinoma Of The Breast: Multicentric Study Of Turkish Society For Radiation Oncology Breast Cancer Study Group (TROD 06-014 Study)(2023) Gurdal, Necla; Yildirim, Berna Akkus; Gursel, Ozge Kandemir; Ozkurt, Selnur; Ibis, Kamuran; Gultekin, Melis; Tepetam, Huseyin; Gul, Sule Karabulut; Guzeloz, Zeliha; Oksuz, Didem Colpan; Cetin, Ilknur Alsan; Yalcin, Berrin; Duzova, Mursel; Kanyilmaz, Gul; Yavas, Guler; Ozsaran, Zeynep; 36464924BackgroundEncapsulated papillary carcinoma (EPC) is a rare malignant papillary breast cancer accounting for approximately .5%-2% of all breast tumors. The aim of this multicenter study was to evaluate clinicopathologic features of EPC in addition to oncological outcomes and radiotherapy (RT) details. MethodsFrom 10 different academic hospitals in Turkey, we obtained pathology reports of 80 patients with histologically confirmed EPC between 2005 and 2022. Demographic, diagnostic, and treatment data were collected from medical records, retrospectively. Local failure, distant progression, toxicity-adverse effects, overall survival (OS), and disease-free survival were evaluated, and survival analyzes were performed using the Kaplan-Meier method. ResultsEighty patients with the diagnosis of misspelled sorry (ECP) were retrospectively evaluated. The median age of the patients was 63 (range, 35-85). After a median follow-up of 48 (range; 6-206) months, local recurrence was observed in three patients (4%). Local recurrence was less common in the patients who received whole breast RT with a tumour bed boost (p = .025). There were not any distant metastasis or disease-related death. RT was applied to 61% of the cases, and no treatment-related grade 3 or higher toxicity was reported in any of the patients. Five year OS, cancer-specific survival (CSS), and were observed as 85%, 100%, and 96%, respectively. ConclusionsECP is a rare, slow-progressing breast carcinoma associated with good prognosis, it is a disease of elderly patient, and usually occurs in postmenopausal women. It responds extremely well to optimal local treatments and appropriate adjuvant treatments on a patient basis, and has excellent OS and CSS ratios.Item 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 Impact Of Serum Albumin-To-Alkaline Phosphatase Ratio In Cervical Cancer Patients Treated With Definitive Chemoradiotherapy(2022) Onal, Cem; Gultekin, Melis; Yavas, Guler; Oymak, Ezgi; Sari, Sezin Yuce; Guler, Ozan Cem; Yigit, Ecem; Yildiz, Ferah; 35653776We retrospectively analysed the prognostic significance of serum albumin, alkaline phosphatase (ALP) and albumin to ALP ratio (AAPR) and other prognostic factors affecting the overall survival (OS) and progression-free survival (PFS) in 200 cervical cancer patients treated with definitive chemoradiotherapy (CRT). The prognostic factors for OS and DFS, in addition to the predictive factors of albumin, ALP and AAPR, were investigated. Older age, lymph node metastasis, non-complete response (CR) to treatment and low serum albumin levels emerged as predictors of poor OS and PFS in multivariate analysis. However, with a cut-off value of 0.51, AAPR was not a significant prognostic factor of survival in multivariable analysis. There were no significant differences in clinicopathological factors between patients with low and high AAPR, except for lymph node metastasis, where lymph node metastasis rate was significantly higher in patients with a low AAPR compared to those with a high AAPR. Patients with CR had a significantly higher serum albumin level and AAPR compared to patients without CR. The pre-treatment serum albumin level was independent predictive for survival; therefore, it could be a suitable biomarker to guide systemic therapy and predict patient outcomes. Impact Statement What is already known on this subject? Two major determinants of tumour progression are nutritional status and inflammation. The albumin-to-alkaline phosphatase ratio (AAPR), which was originally proposed as a marker for nutritional status and immune response, was recently discovered to be a prognostic factor for various cancer types. However, its utility in the treatment of cervical cancer has not been established. What do the results of this study add? Low serum albumin levels were associated with a significantly shorter OS and PFS in cervical cancer patients treated definitively with CRT. AAPR, on the other hand, was not a significant prognostic factor for survival with a cut-off value of 0.51. Regional lymph node metastasis was significantly more common in patients with a low AAPR than in those with a high AAPR. What are the implications of these findings for clinical practice and/or further research? Patients with multiple clinicopathological risk factors and low serum albumin levels had an increased risk of disease recurrence and a poorer prognosis, highlighting the importance of additional adjuvant treatment strategies in these patients. Due to the preliminary nature of our findings, additional research is required to corroborate them.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 Cardiac angiosarcoma treated with 1.5 Tesla MR-guided adaptive stereotactic body radiotherapy-Case report and review of the literature(2022) Noyan, Asli; Yavas, Guler; Arslan, Gungor; Yavas, Cagdas; Onal, Cem; 0000-0002-2742-9021; 36027835; D-5195-2014Introduction: Cardiac angiosarcoma is a very rare disease. As a result of their nonspecific presentation symptoms, and the lack of consensus in treatment, caution should be taken in both diagnosis and treatment. The role of radiotherapy (RT) is debatable due to the continuous movement of the heart, which makes it difficult to safely deliver high radiation doses to the target volume.Presentation of case: The case of a 16-year-old boy with cardiac angiosarcoma that recurred one year after surgery and was treated with chemotherapy is presented. The patient received high field 1.5-Tesla (magnetic resonance) MR-Linac treatment in 5 fractions with a dosage of 25 Gy to the tumor bed and 30 Gy to the recurrent nodules using the simultaneous integrated boost technique. The patient tolerated the treatment well and had stable disease two months later. Discussion: MR-guided radiotherapy, particularly in the case of cardiac malignancies, allows for direct tumor visualization with high soft tissue image resolution capacity. Furthermore, modern RT techniques allow for the full therapeutic window to be used by achieving superior dose distributions, allowing for dose escalation stra-tegies with tolerable toxicity rates.Conclusion: Magnetic resonance guided RT allows direct visualization of the target during treatment delivery, allowing for higher-dose administration with less damage to healthy tissue near the tumor. This treatment strategy is a viable option in selected patients with cardiac angiosarcoma.Item The utility of 1.5 tesla MR-guided adaptive stereotactic body radiotherapy for recurrent ovarian tumor - Case reports and review of the literature(2022) Yavas, Guler; Kuscu, Ulku Esra; Ayhan, Ali; Yavas, Cagdas; Onal, Cem; 36261943Introduction: Although epithelioid ovarian cancer (EOC) is a radiosensitive tumor and radiotherapy (RT) played a significant role in adjuvant treatment management in the past, the role of RT has evolved with the advent of platinum-based chemotherapy regimens. Nonetheless, modern RT techniques may be useful in certain patients particularly those with recurrent disease.Presentation of case: After surgery and chemotherapy, two patients, aged 57 and 70, presented with recurrent lesions in the parailiac region. The recurrent lesions were treated with high field 1.5-Tesla MR-Linac treatment in 5 fractions at a dose of 30 Gy. The patients tolerated the treatment well and were disease free after 12 and 20 months of magnetic resonance guided radiotherapy (MRgRT), respectively.Discussion: MRgRT is a novel and rapidly evolving technology that allows for the highly precise treatment of even mobile targets through direct visualization of the tumor. The majority of patients with EOC frequently present with abdominal-pelvic recurrences. It has been demonstrated that EOC requires high radiation doses for curative treatment. MR-Linac enables monitoring of organ motion during treatment, which is necessary for delivering higher doses to target volumes while sparing surrounding organs.Conclusion: To reduce radiation doses to nearby normal tissues, MRgRT allows for the delivery of hypofractio-nated RT with tight safety margins. Regardless of initial resistance or gradual development of intolerance to standard chemotherapy regimens, the role of RT in patients with persistent or recurrent EOC should be reconsidered.Item Outcome and Safety Analysis of Endometrial Cancer Patients Treated with Postoperative 3D-Conformal Radiotherapy or Intensity Modulated Radiotherapy(2021) Onal, Cem; Sari, Sezin Yuce; Yavas, Guler; Oymak, Ezgi; Birgi, Sumerya Duru; Yigit, Ecem; Guler, Ozan Cem; Gultekin, Melis; Akyurek, Serap; Yildiz, Ferah; 33999750Background We sought to analyze the toxicity rates and the treatment outcomes in endometrial cancer (EC) patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT). Material and methods The clinical data of 646 EC patients treated with postoperative adjuvant 3DCRT (265 patients, 41%) or with IMRT (381 patients, 59%) between April 2007 and August 2019 were retrospectively analyzed. The primary endpoints were treatment-related acute and late gastrointestinal (GI) and genitourinary (GU) toxicities. The secondary endpoints were LC and overall survival (OS) and disease-free survival (DFS). Results Median follow-up time was 37 months. The rates for acute GI and GU toxicities of any grade for the entire group were 55.6% and 46.8%, respectively. Acute grade >= 2 GI toxicity was significantly less in patients treated with IMRT compared to those treated with 3DCRT (11.0% vs. 19.2%, p=.004). However, no significant difference grade >= 2 GU toxicities was observed between the 3DCRT and IMRT groups (15.1% vs. 11.0%; p=.15). Acute grade >= 2 GI and GU toxicities were higher in patients receiving systemic chemotherapy, while paraaortic field irradiation increases only the risk of acute grade >= 2 GI toxicity. Estimated 3-year late grade >= 3 GI toxicity rates in the 3DCRT- and IMRT-treated patients were 4.6% and 1.9% (p= .03), respectively. The patients treated with adjuvant ChT had higher rates of late serious GI complications than those without adjuvant ChT. No significant difference in terms of survival and disease control was observed between the 3DCRT and IMRT treatment groups. No significant factor for LC was found in the multivariate analysis. Conclusion In this multicentric study involving one of largest patient population, we found that IMRT-treated EC patients showed comparable clinical outcomes but with a lower incidence of GI toxicities compared with those treated with 3DCRT.Item Comment on Hunt et al, "Feasibility of magnetic resonance guided radiotherapy for the treatment of bladder cancer"(2021) Yavas, Guler; Yavas, Cagdas; Arslan, Gungor; Onal, Cem; 33912694Item Effects of Adipose-Derived Stem Cells and Platelet-Rich Plasma for Prevention of Alopecia and Other Skin Complications of Radiotherapy(2021) Evin, Nuh; Tosun, Zekeriya; Aktan, Tahsin Murad; Duman, Selcuk; Harmankaya, Ismail; Yavas, Guler; 33141771Background Radiotherapy (RT) involves the use of ionizing radiation in treating malignancies and benign disorders. However, RT damages target and healthy surrounding tissues in a dose-dependent manner. This effectively reduces patient compliance and quality of life, thereby warranting the prevention of RT-induced adverse effects on skin. Adipose-derived stem cells (ASCs) are used to treat RT-induced damage and platelet-rich plasma (PRP) provides a scaffold that potentiates the effects of ASCs. Thus, the aim of this study was to determine the mechanism employed by ASCs and PRP in protecting against RT-induced adverse effects. Methods We have established an immunodeficient mouse transplantation model using which human hair follicular units were implanted. When the follicular units were macroscopically and microscopically mature and anagenic, we administered localized RT. Subsequently, the mice were randomly divided into 4 groups based on the subcutaneous injection of the following to the irradiated transplantation site: saline, PRP, ASCs, and a combination of ASCs and PRP. Next, we used macroscopic and microscopic analyses to determine the protective effects of the injected solutions on skin and hair follicles. Results Adipose-derived stem cells reduced RT-induced adverse effects, such as impaired wound healing, alopecia, skin atrophy, and fibrosis by suppressing inflammation, dystrophy, degeneration, connective tissue synthesis, and apoptosis and increasing cellular proliferation, differentiation, and signaling. Moreover, these effects were augmented by PRP. Conclusions Thus, co-administering ASCs with PRP in mice prevented RT-induced adverse effects and can be tested for use in clinical practice.