Araştırma Çıktıları
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Item Lung cancer subtype differentiation from positron emission tomography images(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2020-01-01) Ayyildiz, Oguzhan; Aydin, Zafer; Yilmaz, Bulent; Karacavus, Seyhan; Senkaya, Kubra; Icer, Semra; Tasdemir, Arzu; Kaya, EserLung cancer is one of the deadly cancer types, and almost 85\% of lung cancers are nonsmall cell lung cancer (NSCLC). In the present study we investigated classification and feature selection methods for the differentiation of two subtypes of NSCLC, namely adenocarcinoma (ADC) and squamous cell carcinoma (SqCC). The major advances in understanding the effects of therapy agents suggest that future targeted therapies will be increasingly subtype specific. We obtained positron emission tomography (PET) images of 93 patients with NSCLC, 39 of which had ADC while the rest had SqCC. Random walk segmentation was applied to delineate three-dimensional tumor volume, and 39 texture features were extracted to grade the tumor subtypes. We examined 11 classifiers with two different feature selection methods and the effect of normalization on accuracy. The classifiers we used were the k-nearest-neighbor, logistic regression, support vector machine, Bayesian network, decision tree, radial basis function network, random forest, AdaBoostM1, and three stacking methods. To evaluate the prediction accuracy we performed a leave-one-out cross-validation experiment on the dataset. We also considered optimizing certain hyperparameters of these models by performing 10-fold cross-validation separately on each training set. We found that the stacking ensemble classifier, which combines a decision tree, AdaBoostM1, and logistic regression methods by a metalearner, was the most accurate method for detecting subtypes of NSCLC, and normalization of feature sets improved the accuracy of the classification method.Item Long-term toxicity and survival outcomes after stereotactic ablative radiotherapy for patients with centrally located thoracic tumors(WALTER DE GRUYTER GMBH, 2020-01-01) Atalar, Banu; Mustafayev, Teuta Zoto; Sio, Terence T.; Sahin, Bilgehan; Gungor, Gorkem; Aydin, Gokhan; Yapici, Bulent; Ozyar, EnisBackground. Stereotactic ablative radiotherapy (SABR) is effective for thoracic cancer and metastasesItem IGFBP-4: A PROMISING BIOMARKER FOR LUNG CANCER(SOC MEDICAL BIOCHEMISTS SERBIA, 2021-01-01) Savas, Irem Nur; Ozturk, Akin; Kavas, Murat; Bulut, Ismet; Alparslan, Sumeyye; Eroglu, Selma Aydogan; Baytemir, Cansel Atinkaya; Kolay, Murat; Coskun, AbdurrahmanBackground: Insulin-like growth factor binding protein-4 (IGFBP-4), a member of the insulin-like growth factor (IGF) family, transports, and regulates the activity of IGFs. The pregnancy-associated plasma protein-A (PAPP-A) has proteolytic activity towards IGFBP-4, and both proteins have been associated with a variety of cancers, including lung cancer. Thus, we aimed to evaluate the use of IGFBP-4 and PAPP-A as potential biomarkers for lung cancer. Methods: Eighty-three volunteers, including 60 patients with lung cancer and 23 healthy individuals, were included in this study. The patients with lung cancer were selected based on their treatment status, histological subgroup, and stage of the disease. Enzyme-linked immunosorbent assays were used to assess the serum levels of IGFBP-4 and PAPPA, whereas the IGF-1 levels were measured using a chemiluminescent immunometric assay. Results: The serum IGFBP-4 levels in all patient groups, regardless of the treatment status and histological differences, were significantly higher than those in the control group (p < 0.005). However, the serum PAPP-A levels in the untreated patient group were found to be higher than those in the control group, but this difference was not statistically significant (p = 0.086). Conclusions: The serum PAPP-A and IGFBP-4 levels are elevated in lung cancer. However, IGFBP-4 may have better potential than PAPP-A as a lung cancer biomarker.Item Sunlight may increase the FDG uptake value in primary tumors of patients with non-small cell lung cancer(SPANDIDOS PUBL LTD, 2013-01-01) Mutlu, Hasan; Buyukcelik, Abdullah; Kaya, Eser; Kibar, Mustafa; Seyrek, Ertugrul; Yavuz, Sinan; Calikusu, ZuleyhaCurrently, positron emission tomography with computerized tomography (PET-CT) is the most sensitive technique for detecting extracranial metastases in non-small cell lung cancer (NSCLC). It has been reported that there is a correlation between the maximal standardized uptake value (SUVmax) of primary tumors and prognosis in patients with NSCLC. The effect of sunlight exposure on PET-CT SUVmax value is not known. Therefore, we aimed to evaluate the effect of sunlight exposure on PET-CT SUVmax a value in patients with NSCLC. A total of 290 patients with NSCLC from two different regions of Turkey (Kayseri, n=168 and Adana, n=122) that have different climate and sunlight exposure intensity, were included in the study. Age, gender, histology of cancer, cancer stage, smoking status, comorbidity and SUVmax of the primary tumor area at the time of staging were evaluated as prognostic factors. In the multivariate analysis, we detected that the region was the only independent factor affecting SUVmax (P=0.019). We identified that warmer climate and more sunlight exposure significantly increases the SUVmax value of the primary tumor area in patients with NSCLC. Further studies are warranted to clarify the issue.Item Cigarette Smoking Increases Pregnancy-associated Plasma Protein-A in Men(UNIV WEST INDIES FACULTY MEDICAL SCIENCES, 2017-01-01) Coskun, A.; Bulut, I.; Serteser, M.; Eren, A.; Ozseker, Z. F.; Cuhadaroglu, C.; Aksungar, F. B.; Ozpinar, A.; Can, O.; Yakar I, H.; Unsal, I.Objective: Elevation of pregnancy-associated plasma protein-A (PAPP-A), a pro-atherosclerotic molecule, has been shown to be an independent risk factor for acute coronary syndrome. Smoking is also an important risk factor for acute coronary syndrome (ACS). However, the molecular mechanism of this relationship is not clear. In the present study, we aimed to determine the association between smoking and serum PAPP-A levels in men and non-pregnant women. Method: The study population consisted of 112 smokers and 58 age-matched non-smoking healthy subjects as a control group. Blood samples were drawn from the antecubital vein of all subjects and serum PAPP-A levels were measured using an ELISA kit (ultrasensitive ELISA). Results: The serum PAPP-A level was significantly high in male smokers (smokers: 9.11 ng/mL (3.10 ng/mL, 18.55 ng/mL))Item Three Cases of Breast Metastases from Lung Cancer and Systematic Review of the Literature(GALENOS YAYINCILIK, 2021-01-01) Guldogan, Nilgun; Icten, Gul Esen; Tokat, Fatma; Tutar, Burcin; Kara, Halil; Korkmaz, Taner; Uluc, Basak Oyan; Demir, GokhanDespite the high prevalence of lung cancer among other primary tumors, metastasis of this particular malignancy in the breast is very rare. We report three new cases of lung cancer with breast metastases and discuss radiological and clinical findings. Radiologically, each case displayed different characteristics. First, one of them had bilateral superficially and deeply located irregular lesions. Second, the patient presented with findings similar to inflammatory breast cancer. The third case had a circumscribed mass, resembling a benign complicated cyst. To guide clinicians for proper patient management, radiologists should be aware of the scope of typical and atypical imaging findings of metastatic involvement of the breast.Item The importance of histological patterns on PD-L1 staining heterogeneity: Should we use pattern-based approach for selecting tumor samples for PD-L1 testing in lung(TUBITAK SCIENTIFIC \& TECHNICAL RESEARCH COUNCIL TURKEY, 2021-01-01) Bulutay, Pinar; Firat, Pinar; Zeren, Handan; Erus, Suat; Tanju, Serhan; Dilege, SukruBackground/aim: Programmed death ligand-1 (PD-L1) is a predictive marker for immunotherapeutic agents. However, heterogeneous staining of PD-L1 can cause false-negative results. The aim of this study is to evaluate the importance of histological patterns on PD-L1 staining heterogeneity in lung adenocarcinomas (LAC). Materials and methods: PD-L1 immunohistochemistry (IHC) stain was performed to two different tissue cores of 128 LAC cases, and cut-off values are given for grouping the cases according to the percentage of staining (1\%-10\%, 11\%-49\%, 50\%-100\%). Staining rates between cores were compared and analyzed by their histological patterns. Also, the relation of the PD-L1 expression with the clinicopathological characteristics of the cases was analyzed. Results: Overall, PD-L1 expression was observed in 53 of 128 cases (41.4\%, 1\% cut-off), 23.5\% of them were positive at 10\% cut-off and 14.1\% at 50\% cut-off. PD-L1 expression was significantly related to the high grade micropapillary and solid patterns of adenocarcinomas (p:0.01). Staining cut-offs were mostly similar between cores (43/50, 86\%) (k:0.843). However, 14\% of them were positive only in one core (7 of 50). This false negativity was mostly related to the histological patterns. Conclusion: Our data reveal the heterogeneous staining of PD-L1 expression, also micropapillary and solid patterns show higher rates of PDL expression. Therewithal, these findings also highlight the importance of taking into consideration of histological patterns, when choosing a paraffin block for the PDL1.