Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item FDG PET/CT Imaging in Prostate Adenocarcinoma Presenting as Isolated Brain Metastases of Unknown Origin(2015) Erhamamci, S.; Reyhan, M.; Alkan, O.; 0000-0001-8550-3368; 0000-0001-7526-3460; 25052407; AAJ-5242-2021; AAM-4169-2021Item In Vitro Effects on Biofilm Viability and Antibacterial and Antiadherent Activities of Silymarin(2015) Evren, Ebru; Yurtcu, Erkan; 0000-0003-4930-8164; 25937395; AAA-2998-2021; JWP-3001-2024Limited treatment options in infectious diseases caused by resistant microorganisms created the need to search new approaches. Several herbal extracts are studied for their enormous therapeutic potential. Silymarin extract, from Silybum marianum (milk thistle), is an old and a new remedy for this goal. The purpose of this study is to evaluate the antibacterial and antiadherent effects of silymarin besides biofilm viability activity on standard bacterial strains. Minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), antiadherent/antibiofilm activity, and effects on biofilm viability of silymarin were evaluated against standard bacterial strains. MIC values were observed between 60 and > 241 mu g/mL (0.25-> 1 mmol/L). Gram-positive bacteria were inhibited at concentrations between 60 and 120 mu g/mL. Gram-negative bacteria were not inhibited by the silymarin concentrations included in this study. MBC values for Gram-positive bacteria were greater than 241 mu g/mL. Adherence/biofilm formations were decreased to 15 mu g/mL silymarin concentration when compared with silymarin-untreated group. Silymarin reduced the biofilm viabilities to 13 and 46 % at 1 and 0.5 mmol/L concentrations, respectively. We demonstrated that silymarin shows antibacterial and antiadherent/antibiofilm activity against certain standard bacterial strains which may be beneficial when used as a dietary supplement or a drug.Item Responding to Veiga Et Al. 'Long Term Radiological Features of Radiation-Induced Lung Damage'(2018) Oymak, Ezgi; Yildirim, Berna Akkus; Guler, Ozan Cem; Onal, Cem; 0000-0001-6661-4185; 0000-0001-6908-3412; 0000-0002-2742-9021; 30021696; AGG-9214-2022; V-5717-2017; AAC-5654-2020; D-5195-2014Item Clinicopathological features, MCPyV status and outcomes of Merkel cell carcinoma in solid-organ transplant recipients: a retrospective, multicentre cohort study(2022) Ferrandiz-Pulido, C.; Gomez-Tomas, A.; Llombart, B.; Mendoza, D.; Marcoval, J.; Piaserico, S.; Baykal, C.; Bouwes-Bavinck, J.N.; Racz, E.; Kanitakis, J.; Harwood, C.A.; Cetkovska, P.; Geusau, A.; Del Marmol, V; Masferrer, E.; Cano, C.Orte; Ricar, J.; de Oliveira, W.R.; Salido-Vallejo, R.; Ducroux, E.; Gkini, M.A.; Lopez-Guerrero, J.A.; Kutzner, H.; Kempf, W.; Seckin, D.; 35607918Background The proportion of Merkel cell carcinomas (MCCs) in solid-organ transplant recipients (SOTR) harbouring Merkel cell polyomavirus (MCPyV) is unknown, as are factors affecting their outcomes. Objective To describe clinicopathological features of MCC in SOTR, investigate the tumoral MCPyV-status and identify factors associated with tumour outcomes. Methods Retrospective, international, cohort-study. MCPyV-status was investigated by immunohistochemistry and polymerase chain reaction. Results A total of 30 SOTR and 44 consecutive immunocompetent patients with MCC were enrolled. SOTR were younger at diagnosis (69 vs. 78 years, P < 0.001). Thirty-three percent of SOTR MCCs were MCPyV-positive vs. 91% of immunocompetent MCCs (P = 0.001). Solid-organ transplantation was associated with an increased cumulative incidence of progression (SHR: 3.35 [1.57-7.14], P = 0.002), MCC-specific mortality (SHR: 2.55 [1.07-6.06], P = 0.034) and overall mortality (HR: 3.26 [1.54-6.9], P = 0.002). MCPyV-positivity and switching to an mTOR inhibitor (mTORi) after MCC diagnosis were associated with an increased incidence of progression (SHR: 4.3 [1.5-13], P = 0.008 and SHR: 3.6 [1.1-12], P = 0.032 respectively) in SOTR. Limitations Retrospective design and heterogeneity of SOTR cohort. Conclusions MCPyV appears to play a less prominent role in the aetiopathogenesis of MCC in SOTR. SOTR have a worse prognosis than their immunocompetent counterparts and switching to an mTORi after the diagnosis of MCC does not improve progression.Item Prognostic Value of Pretreatment Systemic Immune-Inflammation Index in Glioblastoma Multiforme Patients Undergoing Postneurosurgical Radiotherapy Plus Concurrent and Adjuvant Temozolomide(2020) Topkan, Erkan; Besen, Ali Ayberk; Ozdemir, Yurday; Kucuk, Ahmet; Mertsoylu, Huseyin; Pehlivan, Berrin; Selek, Ugur; 0000-0002-1932-9784; 0000-0002-2218-2074; 0000-0001-8120-7123; 0000-0002-7862-0192; 32565725; M-9530-2014; AAG-5629-2021; AAG-2213-2021; AAD-6910-2021Objectives. To evaluate the potential prognostic utility of pretreatment systemic immune-inflammation index (SII) in newly diagnosed glioblastoma multiforme (GBM) patients who underwent postneurosurgical radiotherapy and concurrent plus adjuvant temozolomide. Methods. The retrospective data of GBM patients who underwent postneurosurgical radiotherapy and concurrent plus adjuvant temozolomide were analyzed. For each patient, SII was calculated using the platelet, neutrophil, and lymphocyte measures obtained on the first day of treatment: SII=plateletsxneutrophils/lymphocytes. The receiver operating characteristic (ROC) curve analysis was utilized for the evaluation of optimal cut-off values for SII those linked with the outcomes. Primary and secondary endpoints constituted the overall (OS) and progression-free survival (PFS) per conveyance SII group. Results. A total of 167 patients were included. The ROC curve analysis identified the optimum SII cut-off at a rounded 565 value that significantly interacted with the PFS and OS and stratified patients into two groups: low-SII (SII<565; n=71) and high-SII (SII >= 565; n=96), respectively. Comparative survival analyses exhibited that the high-SII cohort had significantly shorter median PFS (6.0 versus 16.6 months; P<0.001) and OS (11.1 versus 22.9 months; P<0.001) than the low-SII cohort. The relationship between the high-SII and poorer PFS (P<0.001) and OS (P<0.001) further retained its independent significance in multivariate analysis, as well. Conclusions. The outcomes displayed here qualified the pretreatment SII as a novel independent prognostic index for predicting survival outcomes of newly diagnosed GBM patients undergoing postneurosurgical radiotherapy and concurrent plus adjuvant temozolomide.Item Low Systemic Inflammation Response Index Predicts Good Prognosis in Locally Advanced Pancreatic Carcinoma Patients Treated with Concurrent Chemoradiotherapy(2020) Topkan, Erkan; Mertsoylu, Huseyin; Kucuk, Ahmet; Besen, Ali Ayberk; Sezer, Ahmet; Sezen, Duygu; Bolukbasi, Yasemin; Selek, Ugur; Pehlivan, Berrin; 0000-0002-7862-0192; 0000-0002-6445-1439; 0000-0002-1932-9784; 0000-0001-8120-7123; AAD-6910-2021; AAD-2667-2020; M-9530-2014; AAG-2213-2021Background. We investigated the prognostic significance of pretreatment systemic inflammation response index (SIRI) in locally advanced pancreatic carcinoma (LAPC) patients treated with concurrent chemoradiotherapy (CRT). Methods. Present retrospective cohort analysis investigated consecutive 154 LAPC patients who received radical CRT. The SIRI was defined as:SIRI=neutrophilxmonocyte/lymphocyte counts. Ideal SIRI cutoff(s) influencing overall survival (OS) and progression-free survival (PFS) results were sought by using receiver operating characteristic (ROC) curve analysis. The primary endpoint was the interaction between the SIRI and OS results. Results. The median follow-up, PFS, and OS durations were 14.3 (range: 2.9-74.6), 7.9 [%95 confidence interval (CI): 5.7-10.1), and 14.7 months (%95 CI: 11.4-18.0) for the entire cohort, respectively. ROC curve analyses determined the ideal SIRI cutoff that exhibiting a significant link with OS and PFS outcomes at the rounded 1.6 point (AUC: 74.3%; sensitivity: 73.8%; specificity: 70.1%).The SIRI <1.6 patients (N=58) had significantly superior median PFS (13.8 versus 6.7 months; P<0.001) and OS (28.6 versus 12.6 months; P<0.001) lengths than SIRI >= 1.6 patients (N=96), respectively. Although the N0 (versus N1; P<0.05) and CA 19-9 <= 90 U/mL (versus >90 U/mL) appeared as the other significant associates of better OS and PFS in univariate analyses, yet the results of multivariate analyses confirmed the SIRI <1.6 as the independent indicator of superior OS and PFS (P<0.001 for each). Conclusion. Pretreatment SIRI is a novel independent prognosticator that may further enhance the conventional tumor-node-metastases staging system in a more precise prediction of the OS and PFS outcomes of LAPC patients after radical CRT.Item Comparison of Involved Field Radiotherapy versus Elective Nodal Irradiation in Stage IIIB/C Non-Small-Cell Lung Carcinoma Patients Treated with Concurrent Chemoradiotherapy: A Propensity Score Matching Study(2020) Topkan, Erkan; Ozdemir, Yurday; Guler, Ozan Cem; Kucuk, Ahmet; Besen, Ali Ayberk; Mertsoylu, Huseyin; Sezen, Duygu; Akdemir, Eyub Yasar; Sezer, Ahmet; Bolukbasi, Yasemin; Pehlivan, Berrin; Selek, Ugur; 0000-0002-1932-9784; 0000-0001-6908-3412; 0000-0002-2218-2074; 0000-0002-6445-1439; 0000-0001-8120-7123; 0000-0002-7862-0192; 32952557; M-9530-2014; AAC-5654-2020; AAG-5629-2021; AAD-2667-2020; AAG-2213-2021; AAD-6910-2021Background. We retrospectively compared the incidence of isolated elective nodal failure (IENF) and toxicity rates and survival outcomes after elective nodal irradiation (ENI) versus involved-field RT (IFRT) by employing the propensity score matching (PSM) methodology in stage IIIB/C inoperable non-small-cell lung cancer (NSCLC) patients treated with definitive concurrent chemoradiotherapy (C-CRT).Methods. Our PSM examination included 1048 stage IIIB/C NSCLC patients treated with C-CRT from January 2007 to December 2016: a total dose of 66 Gy (2 Gy/fraction) radiotherapy and 1-3 cycles of platinum-based doublet chemotherapy concurrently. The primary and secondary endpoints were the IENF and toxicity rates and survival outcomes after ENI versus IFRT, respectively. Propensity scores were calculated for each group to adjust for confounding variables and facilitate well-balanced comparability by creating 1 : 1 matched study groups.Results. The median follow-up was 26.4 months for the whole study accomplice. The PSM analysis unveiled 1 : 1 matched 646 patients for the ENI (N = 323) and IFRT (N = 323) cohorts. Intergroup comparisons discovered that the 5-year isolated ENF incidence rates (3.4% versus 4.3%;P=0.52) and median overall survival (25.2 versus 24.6 months;P=0.69), locoregional progression-free survival (15.3 versus 15.1 months;P=0.52), and progression-free survival (11.7 versus 11.2 months;P=0.57) durations were similar between the ENI and IFRT cohorts, separately. However, acute grade 3-4 leukopenia (P=0.0012), grade 3 nausea-vomiting (P=0.006), esophagitis (P=0.003), pneumonitis (P=0.002), late grade 3-4 esophageal toxicity (P=0.038), and the need for hospitalization (P<0.001) were all significantly higher in the ENI than in the IFRT group, respectively.Conclusion. Results of the present large-scale PSM cohort established the absence of meaningful IENF or survival differences between the IFRT and ENI cohorts and, consequently, counseled the IFRT as the elected RT technique for such patients since ENI increased the toxicity rates.Item The effect of helicobacter pylori eradication on atrophic gastritis and intestinal metaplasia : a retrospective single center research(2020) Suna, N.; Etik, D.; Ocal, S.; Gunduz, C.; Acikgoz, A.; Bildik, I; Gursoy, A.; Kasgoz, I; Tuleylioglu, H.; Boyacioglu, A.; 0000-0003-3719-9482; 0000-0002-4724-0728; 0000-0001-6234-7788; 33094583; ABH-4817-2020; AAJ-4707-2021; AAI-8822-2021Background and study aims : Gastric cancer (GC) is one of the major causes of cancer-related deaths worldwide. Helicobacter pylori (Hp) plays an important role in gastric carcinogenesis by inducing precancerous changes such as atrophic gastritis (AG) and intestinal metaplasia (IM). In our study, we aim to compare the grade of AG and IM before and after Hp eradication in patients who underwent esophagogastroduodenoscopy (EGD) in our center. Patients and methods : The data of 40.060 patients who underwent EGD for various reasons in our Endoscopy Unit between June 2011 and November 2017 were retrospectively evaluated. The grade of AG and IM before and after Hp eradication of patients meeting the study criteria were compared with each other. In addition, these findings were compared using OLGA and OLGIM staging systems. Results : A total of 175 patients, 89 (50.9%) women and 86 (49.1%) men, were included in the study. The mean age was 55 +/- 12 years. The mean time between two EGD examinations was 38 +/- 14 months. Significant improvement was observed in the grade of AG on corpus and antrum after Hp eradication (P=0.000, P=0.008). In the corpus and antrum, the grade of IM was regressed but this was not significant (P=0.80 and P=0.370 respectively). There was a decrease in OLGA stages after Hp eradication (P=0.000). There was also a reduction in the OLGIM stages, but this was not significant(P=0.341). Conclusion: Our study demonstrates that Hp eradication may reduce the risk of developing GC by providing an improvement in AG and IM which are precancerous changes in GC.Item Systemic Inflammation Response Index Predicts Survival Outcomes in Glioblastoma Multiforme Patients Treated with Standard Stupp Protocol(2020) Topkan, Erkan; Kucuk, Ahmet; Ozdemir, Yurday; Mertsoylu, Huseyin; Besen, Ali Ayberk; Sezen, Duygu; Bolukbasi, Yasemin; Pehlivan, Berrin; Selek, Ugur; 0000-0002-7862-0192; 0000-0001-8120-7123; 0000-0002-2218-2074; 0000-0002-1932-9784; 33274245; AAD-6910-2021; AAG-2213-2021; AAG-5629-2021; M-9530-2014Objectives. We endeavored to retrospectively assess the prognostic merit of pretreatment systemic immune response index (SIRI) in glioblastoma multiforme (GBM) patients who underwent postoperative partial brain radiotherapy (RT) and concurrent plus adjuvant temozolomide (TMZ), namely, the Stupp protocol. Methods. The records of 181 newly diagnosed GBM patients who received the postoperative Stupp protocol were retrospectively analyzed. The SIRI value for each eligible patient was calculated by utilizing the platelet, neutrophil, and lymphocyte measures obtained on the first day of treatment: SIRI=NeutrophilsxMonocytes/Lymphocytes. The ideal cutoff values for SIRI connected with the progression-free- (PFS) and overall survival (OS) results were methodically searched through using the receiver operating characteristic (ROC) curve analysis. Primary and secondary end-points constituted the potential OS and PFS distinctions among the SIRI groups, respectively. Results. The ROC curve analysis labeled the ideal SIRI cutoffs at 1.74 (Area under the curve (AUC): 74.9%; sensitivity: 74.2%; specificity: 71.4%) and 1.78 (AUC: 73.6%; sensitivity: 73.1%; specificity: 70.8%) for PFS and OS status, individually. The SIRI cutoff of 1.78 of the OS status was chosen as the common cutoff for the stratification of the study population (Group 1: SIRI <= 1.78 (N=96) and SIRI>1.78 (N=85)) and further comparative PFS and OS analyses. Comparisons between the two SIRI cohorts manifested that the SIRI <= 1.78 cohort had altogether significantly superior median PFS (16.2 versus 6.6 months; P<0.001) and OS (22.9 versus 12.2 months; P<0.001) than its SIRI>1.78 counterparts. The results of multivariate Cox regression analyses ratified the independent and significant alliance between a low SIRI and longer PFS (P<0.001) and OS (P<0.001) durations, respectively. Conclusions. Present results firmly counseled the pretreatment SIRI as a novel, sound, and independent predictor of survival outcomes in newly diagnosed GBM patients intended to undergo postoperative Stupp protocol.Item Significance of overall concurrent chemoradiotherapy duration on survival outcomes of stage IIIB/C non-small-cell lung carcinoma patients: Analysis of 956 patients(2019) Topkan, Erkan; Ozdemir, Yurday; Kucuk, Ahmet; Besen, Ali Ayberk; Mertsoylu, Huseyin; Sezer, Ahmet; Selek, Ugur; 31329602Background To investigate the detrimental effects of prolonged overall radiotherapy duration (ORTD) on survival outcomes of stage IIIB/C NSCLC patients treated with concurrent chemoradiotherapy (C-CRT) Methods The study cohort consisted of 956 patients who underwent C-CRT for stage IIIB/C NSCLC. Primary endpoint was the association between the ORTD and overall survival (OS) with locoregional progression-free survival (LRPFS) and PFS comprising the secondary endpoints. Receiver operating characteristic (ROC) curve analysis was utilized for accessibility of the cut-off that interacts with survival outcomes. Multivariate Cox model was utilized to identify the independent associates of survival outcomes. Results The ROC curve analysis exhibited significance at 49 days of ORTD cut-off that dichotomized patients into ORTD<50 versus ORTD >= 50 days groups for OS [area under the curve (AUC): 82.8%; sensitivity: 81.1%; specificity: 74.8%], LRPFS (AUC: 91.9%; sensitivity: 90.6%; specificity: 76.3%), and PFS (AUC: 76.1%; sensitivity: 72.4%; specificity: 68.2%), respectively. Accordingly, ORTD >= 50 days group had significantly shorter median OS (P<0.001), LRPFS (P<0.001), and PFS (P<0.001); and 10-year actuarial locoregional control (P<0.001) and distant metastases-free (P<0.011) rates than the ORTD<50 days group. The ORTD retained its significant association with survival outcomes at multivariate analyses independent of the other favorable covariates (p<0.001, for OS, LRPFS, and PFS): Stage IIIB disease (versus IIIC), lymph node bulk <2 cm (versus >= 2 cm), and 2-3 chemotherapy cycles (versus 1). The higher sensitivity for LRPFS (90.6%) than PFS (72.4%) on ROC curve analysis suggested the prolonged ORTD-induced decrements in locoregional control rates as the major cause of the poor survival outcomes. Conclusions Longer ORTD beyond >= 50 days was associated with significantly poorer OS, LRPFS and PFS outcomes, where reduced locoregional control rates appeared to be the main causative.