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Öğe Adrenocortical Cancer in the Real World: A Comprehensive Analysis of Clinical Features and Management from the Turkish Oncology Group (TOG)(Cig Media Group, Lp, 2024) Yasar, Hatime Arzu; Aktas, Burak Yasin; Ucar, Gokhan; Goksu, Sema Sezgin; Bilgetekin, Irem; Cakar, Burcu; Sakin, AbdullahAdrenocortical cancer is a rare and poor prognostic malignant tumor. The definitions of prognostic factors in localized and metastatic diseases are important. In this paper, we defined the clinical features, management, and prognostic factors related to survival in patients with metastatic and nonmetastatic ACC. Cox regression analysis showed that age, Ki67 value, ECOG PS, and hormonal activity were significantly associated with survival in patients with nonmetastatic disease. Only patients who underwent surgery had significantly better OS compared with patients without surgery in univariate analyses of metastatic disease. Introduction: Adrenocortical carcinoma (ACC) is a rare yet highly malignant tumor associated with significant morbidity and mortality. This study aims to delineate the clinical features, survival patterns, and treatment modalities of ACC, providing insights into the disease's prognosis. Materials and Methods: A retrospective analysis of 157 ACC patients was performed to assess treatment methodologies, demographic patterns, pathological and clinical attributes, and laboratory results. The data were extracted from the hospital's database. Survival analyses were conducted using the Kaplan-Meier method, with univariate and multivariate analyses being performed through the log -rank test and Cox regression analyses. Results: The median age was 45, and 89.4% had symptoms at the time of diagnosis. The median tumor size was 12 cm. A total of 117 (79.6%) patients underwent surgery. A positive surgical border was detected in 26 (24.1%) patients. Adjuvant therapy was administered to 44.4% of patients. The median overall survival for the entire cohort was 44.3 months. Median OS was found to be 87.3 months (95% confidence interval [CI] 74.4-100.2) in stage 2, 25.8 (95% CI 6.5-45.1) months in stage 3, and 13.3 (95% CI 7.0-19.6) months in stage 4 disease. Cox regression analysis identified age, Ki67 value, Eastern Cooperative Oncology Group performance status, and hormonal activity as significant factors associated with survival in patients with nonmetastatic disease. In metastatic disease, only patients who underwent surgery exhibited significantly improved overall survival in univariate analyses. Conclusion: ACC is an uncommon tumor with a generally poor prognosis. Understanding the defining prognostic factors in both localized and metastatic diseases is vital. This study underscores age, Ki67 value, Eastern Cooperative Oncology Group performance status, and hormonal activity as key prognostic determinants for localized disease, offer ing cr itical insights into the complexities of ACC management and potential avenues for targeted therapeutic interventions.Öğe Clinical Features and Prognostic Factors of Metastatic Non-Clear Cell Renal Cell Carcinoma: A Multicenter Study from the Turkish Oncology Group Kidney Cancer Consortium(Karger, 2023) Erol, Cihan; Yekeduz, Emre; Tural, Deniz; Karakaya, Serdar; Oztas, Nihan Senturk; Ucar, Gokhan; Kilickap, SaadettinIntroduction: We aimed to evaluate clinical features, prognostic factors, and treatment preferences in patients with non-clear cell renal cell carcinoma (nccRCC). Methods: Patients with metastatic nccRCC were selected from the Turkish Oncology Group Kidney Cancer Consortium (TKCC) database. Clinical features, prognostic factors, and overall survival (OS) outcomes were investigated. Results: A total of 118 patients diagnosed with nccRCC were included in this study. The median age at diagnosis was 62 years (interquartile range: 56-69). Papillary (57.6%) and chromophobe tumors (12.7%) are common histologic subtypes. Sarcomatoid differentiation was present in 19.5% of all patients. When the patients were categorized according to the International Metastatic RCC Database Consortium (IMDC) risk scores, 66.9% of the patients were found to be in the intermediate or poor risk group. Approximately half of the patients (55.9%) received interferon in the first line. At the median follow-up of 53.2 months (95% confidence interval [CI]: 34.7-71.8), the median OS was 19.3 months (95% CI: 14.1-24.5). In multivariate analysis, lung metastasis (hazard ratio [HR]:2.22, 95% CI: 1.23-3.99) and IMDC risk score (HR: 2.35, 95% CI: 1.01-5.44 for intermediate risk; HR: 8.86, 95% CI: 3.47-22.61 for poor risk) were found to be independent prognostic factors. Conclusion: In this study, survival outcomes are consistent with previous studies. The IMDC risk score and lung metastasis are the independent prognostic factors for OS. This is an area that needs research to better treat this group of patients and create new treatment options.Öğe Coliform bacteria immobilized on titanium dioxide nanoparticles as a biosorbent for trace lead preconcentration followed by atomic absorption spectrometric determination(Springer Wien, 2011) Bakircioglu, Dilek; Ucar, Gokhan; Kurtulus, Yasemin BakirciogluColiform bacteria physically immobilized on titanium dioxide nanoparticles can be used as a biosorbent for solid phase extraction of lead (II) ions from aqueous solution using a flow injection system coupled to flame atomic absorption spectrometry (FAAS). Effects of pH value, sample volume, flow rates of loading and elution, and the type and volume of eluent were investigated. Lead ions were sorbed on a biosorbent mini-column at pH 6.0, eluted with 1 mol L-1 HCl and then determined by FAAS. The limit of detection for the water samples is in order of 0.90 mu g L-1. The accuracy of the method was confirmed by analyzing a certified reference material (GBW 07605; tea). The results are in good agreement with the certified value. The precision of the method was also satisfactory. The procedure was applied to the evaluation of lead ions in river water, wine, and baby food.Öğe Determination of some traces metal levels in cheese samples packaged in plastic and tin containers by ICP-OES after dry, wet and microwave digestion(Pergamon-Elsevier Science Ltd, 2011) Bakircioglu, Dilek; Kurtulus, Yasemin Bakircioglu; Ucar, GokhanThe concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, Se and Zn in cheese samples packaged in plastic and tin containers were analyzed using inductively coupled plasma-optical emission spectrometry after microwave, wet and dry digestion processes. In order to evaluate the best digestion method, the relationships between the concentrations of trace metals in cheese samples after microwave digestion was compared by wet and dry ashings. Microwave digestion was found fast, reliable, simple, and excellent procedure in comparison with dry and wet ashing methods. The accuracy of the digestion procedures was determined by using standard reference material (GBW 07605-Tea). The order of levels of the elements in the white cheese samples packaged in tin containers was determined to be Cd < Co < Mn < Cr < Se < Pb < Cu < Ni < Zn, after microwave digestion and cream cheese samples in plastic containers Cd < Mn < Co < Cr < Se < Pb < Ni < Cu < Zn, respectively. There were considerable differences among of the studied element contents of cheese samples packaged in tin and plastic containers, indicating that cheese types and packaging materials play a key role in the content of trace metal. (C) 2010 Elsevier Ltd. All rights reserved.Öğe External Validation of a Novel Risk Model in Patients With Favorable Risk Renal Cell Carcinoma Defined by International Metastatic Renal Cell Carcinoma Database Consortium (IMDC): Results From the Turkish Oncology Group Kidney Cancer Consortium (TKCC) Database(Cig Media Group, Lp, 2023) Yekeduz, Emre; Karakaya, Serdar; Erturk, Ismail; Tural, Deniz; Ucar, Gokhan; Oztas, Nihan Senturk; Arikan, RukiyeIn this report, we validated a novel prognostic model structured by the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) for patients with metastatic renal cell carcinoma. The former favor-able risk group was divided into 2 new categories: very favorable and favorable. Patients with very favorable risk had better survival than those with the novel favorable risk. Further studies are needed to evaluate whether less intensive therapies could be as effective as current combinations of therapies in the very favorable risk group. Background: A novel prognostic model was recommended for patients with metastatic RCC (mRCC) by the Interna-tional mRCC Database Consortium (IMDC). In this study, we aimed to externally validate a novel risk model for the IMDC-favorable risk group in patients with mRCC. Methods: The Turkish Oncology Group Kidney Cancer Consortium (TKCC) is a multicenter registry that includes 13 cancer centers in Turkey. As described by Schmidt et al., 3 parameters (ie, time from diagnosis to systemic therapy < 3 vs. >3 years, Kar nofsky Perfor mance Status [KPS] 80 vs. > 80, and the presence of brain, liver, or bone metastasis) were used to divide the IMDC favorable risk group into 2 new categories: very favorable and favorable risk groups. The primary endpoint was overall survival (OS). Time to treatment failure (TTF) and objective response rate (ORR) in the very favorable and favorable risk groups were the secondary endpoints. Results: A total of 545 patients with mRCC from all IMDC risk groups and 112 patients from the favorable risk group were included in this study. According to the novel classification model, 44 (39.3%) and 68 (60.7%) patients with former favorable risk were categorized into very favorable and favorable risk groups, respectively. The median OS (55.8 months vs. 34.2 months, P = .025) and TTF (25.5 months vs. 15.5 months, P = .010) were longer in the very favorable risk group than in the favorable risk group. The concordance index of the new IMDC model in all patients was 0.65 for OS. Despite the higher ORR in the very favorable risk group than in the favorable risk group, the difference between the groups was not statistically significant (52.4% vs. 44.7, P = .573). Conclusions: This was the first study to externally validate the novel IMDC risk model presented in the American Society of Clinical Oncology Genitourinary Cancers Symposium 2021.Öğe Neutrophil-lymphocyte ratio as a prognostic factor for survival in patients with advanced renal cell carcinoma (Turkish Oncology Group Study)(Sage Publications Ltd, 2020) Hizal, Mutlu; Sendur, Mehmet A. N.; Yasar, Hatime Arzu; Bir Yucel, Kadriye; Arslan, Cagatay; Ucar, Gokhan; Karakaya, SerdarBackground To describe the prognostic value of neutrophil-lymphocyte ratio and its effect on survival in in patients with advanced renal cell carcinoma. Methods We retrospectively analyzed 331 patients. The cut-off value of neutrophil-lymphocyte ratio was specified as 3 which is mostly close-and also clinically easily applicable-to the median neutrophil-lymphocyte ratio level of our study group. High group is identified as neutrophil-lymphocyte ratio >3 (n = 160) and low group is identified as neutrophil-lymphocyte ratio <= 3 (n = 163). Results A total of 331 (with 211 male and 120 female) patients were enrolled to study. The median age of the patients was 58. The International Metastatic RCC Database Consortium risk score is calculated for the 72.8% (n = 241) of the study group and among these patients, favorable, intermediate, and poor risk rates were 22, 45.2, and 32.8%. The total usage of tyrosine kinase inhibitors reached 78% of the patients. The median overall survival was 32 months versus 11 months in the neutrophil-lymphocyte ratio low and high groups, respectively (HR: 0.49 (95% CI 0.37-0.65), p < 0.001). Conclusion In conclusion, the pre-treatment value of elevated neutrophil-lymphocyte ratio might be a predictor of poor overall survival in advanced renal cell carcinoma patients.Öğe Real life data from Turkey regarding the impact of first-line sunitinib and pazopanib in metastatic renal cell cancer.(Amer Soc Clinical Oncology, 2019) Isik, Ulas; Kostek, Osman; Demiray, Gokcen; Dirican, Ahmet; Simsek, Melih; Buyuksimsek, Mahmut; Ucar, Gokhan[Abstract Not Available]Öğe The relationship between prognostic nutritional index and treatment response in patients with metastatic renal cell cancer(Sage Publications Ltd, 2020) Yasar, Hatime Arzu; Yucel, Kadriye Bir; Arslan, Cagatay; Ucar, Gokhan; Karakaya, Serdar; Bilgin, Burak; Taban, HakanIntroduction and aim To investigate the effect of the prognostic nutritional index on treatment response and survival in patients with metastatic renal cell cancer. Methods We retrospectively analyzed the treatment modalities; the demographic, clinical and pathological features of 396 patients with RCC and prognostic nutritional index. Based on the median value, patients were grouped as having low and high prognostic nutritional index values. Kaplan-Meier method was used for survival analysis, and Cox-regression analysis was used for multivariate analysis. Results The median overall survival was 39 months (95% CI 26.1-51.8), 28 months (95% CI 17.9-38) and 7 months (95% CI 4.7-9.2) in patients with favorable, intermediate and poor International Metastatic Renal Cell Carcinoma Database Consortium risk group, respectively. The difference between the groups was statistically significant (p < 0001). Overall survival was 11 months (95% CI 7.5-14.5) in the low-prognostic nutritional index (prognostic nutritional index <= 38.5) group, and 41 months (95% CI 30.5-51.4) in the high prognostic nutritional index (prognostic nutritional index >38.5) group (p < 0.001). In Cox regression analysis, Eastern Cooperative Oncology Group performance score (HR: 2.5), time to systemic treatment (HR: 1.7) and prognostic nutritional index (HR: 1.8) were associated with overall survival. Conclusion In patients with renal cell cancer, prognostic nutritional index is closely related to survival and has prognostic significance.Öğe Sunitinib or Pazopanib: Is There Any Difference Between Tyrosine Kinase Inhibitors in the Pre-Nivolumab Setting in Metastatic Renal Cell Carcinoma?(Springernature, 2020) Ucar, Gokhan; Acikgoz, Yusuf; Ergun, Yakup; Bal, Oznur; Yilmaz, Mesut; Karakaya, Serdar; Akdeniz, NadiyeIntroduction Treatment options for metastatic renal cell carcinoma disease have been improved in recent years. However, there is still no optimal treatment sequence or combination for metastatic disease. We aimed to investigate whether patients differed in terms of disease outcomes regarding pre-nivolumab tyrosine kinase inhibitors (TKIs). Material and methods The analysis of patients was performed after all cohorts were sub-grouped into two groups according to pre-nivolumab TKIs as following the sunitinib arm and the pazopanib arm. Result A total of 75 patients were included in this study. The median follow-up time was eight months for all cohorts. The objective response rate was statistically significantly higher in the pazopanib arm as compared to the sunitinib arm (56% vs 30%, p=0.02). Progression-free survival was significantly higher in pazopanib than sunitinib (10.3 months vs 5.3 months, p=0.02). Multivariate analysis revealed that pazopanib treatment was associated with better progression-free survival (HR: 0.44, 95 CI; 0.22-0.91, p=0.02). While the median overall survival for patients who had received sunitinib was 11.0 months, it has not been reached the median in the pazopanib arm (11.0 months vs NR, p=0.051). Discussion We demonstrated significantly better progression-free survival and a higher objective response rate with nivolumab treatment in patients who had received pazopanib as compared with patients who received sunitinib in the pre-nivolumab period.