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Öğe Assessment of Duodenal Diverticula: Computed Tomography Findings(Bentham Science Publ Ltd, 2019) Yilmaz, Erdem; Kostek, Osman; Hereklioglu, Savas; Goktas, Muhammet; Tuncbilek, NerminAims: To demonstrate the prevalence, accompanying pathologies, imaging and follow up findings of Duodenal Diverticula (DD) with Multidetector Computed Tomography (MDCT). Materials and Methods: Consecutive 2910 abdominal MDCTs were retrospectively reviewed on axial, coronal and sagittal planes. DD were evaluated for prevalence, location, number, size, contents, diverticular neck, accompanying pancreaticobiliary pathologies, jejunal and colonic diverticula, respectively. Results: DD were diagnosed in 157 cases (5.4%) and found mostly in the second part of the duodenum. Juxta-ampullary DD was the most common type (78.3%) and mostly located ventral (n:86, 69.9%) to the ampulla of Vater. DD was solitary in 123 patients (78.3%) and more than one in 34 patients (21.7%). The median diameter of DD was 2.5 cm (range 1.5-3.6 cm) in the long-axis. The lumen of DD contains air and contrast agent (n:96, 61.1%); air, contrast agent and debris (n:42, 26.7%) in most cases. Colonic diverticula (n:36, 22.9%), cholelithiasis (n:32, 20.4%), choledocholithiasis (n:7, 4.4%), and biliary dilatation (n:8, 5.1%) were the most common additional findings. Median follow-up time was 23 months (range 11 to 41 months). In three cases, new findings (cholelithiasis, n:3, choledocholithiasis, n:1) were detected. Conclusion: Accompanying pathologies with DD diagnosis are valuable for physicians in order to manage the patients. Following clinical and radiological features of well-diagnosed DD might reduce the possible complications.Öğe Assessment of Prognostic Factors in Epithelial Ovarian Cancer(Kare Publ, 2017) Onal, Yilmaz; Kostek, Osman; Hacioglu, Muhammet Bekir; Erdogan, Bulent; Kodaz, Hilmi; Bekmez, Esma Turkmen; Hacibekiroglu, IlhanObjectives: Ovarian cancer is the second most common gynecological cancer, and has a 5-year survival rate of about 40% to 45%. This ratio ranges from 15% to 95%, based on prognostic factors. There are numerous clinical, pathological and biological factors related to prognosis. The aim of this study was to assess prognostic factors in advanced epithelial ovarian cancer. Methods: A total of 119 stage III and stage IV ovarian cancer patients were evaluated. The patients age, menopausal status, age of menarche, number of children, height and weight values, surgery, tumor histopathological features, presence of metastasis, residual tumor volume, presence of ascites, abdominal lavage cytology, chemotherapy regimen, number of chemotherapy cycles, the first and last chemotherapy dates, relapse, and recent status were evaluated. Results: The median age of the study patients was 54 years (minimum: 34, maximum: 79 years). The pathological stages were 10 (8.6%) patients with IIIA, 6 (5%) patients with IIIB, 76 (63.9%) patients with IIIC, and 27 (22.7%) patients with stage IV. In multivariate analysis, age of diagnosis (hazard ratio [HR]: 0.44; 95% confidence interval [CI], 0.22-087; p=0.01), postoperative tumor residual status (HR: 0.32; 95% CI, 0.14-0.71; p<0.01), number of adjuvant chemotherapies (HR: 0.48; 95% CI, 0.23-0.98; p=0.04), and platinum sensitivity (HR: 0.37; 95% CI, 0.18-0.74; p<0.01) were found to be independent variables related to longer survival. Notably, a patient treated with more than 6 cycles of chemotherapy had a worse prognosis. Conclusion: Independent indicators of a poor prognosis in our study were determined to be advanced age at diagnosis, a residual tumor more than 2 cm in size, more than 6 cycles of chemotherapy, and the presence of platinum-resistant disease. A multidisciplinary approach is needed to improve prognosis.Öğe C-Reactive Protein to Albumin Ratio is an Indicator of Poor Prognosis for Patients with Biliary Tract Cancer(Kare Publ, 2020) Demir, Tarik; Kostek, Osman; Araz, Murat; Sakin, Abdullah; Aliyev, Altay; Besiroglu, Mehmet; Turk, Haci MehmetObjectives: This retrospective study evaluated the prognostic significance of the ratio of C-reactive protein (CRP) to albumin (Alb) in patients with biliary tract cancer (BTC). Methods: A total of 178 patients with newly diagnosed BTC, who had been treated in our departments between January 2013 and September 2018, were enrolled in the study. All medical records were reviewed retrospectively. Patients who showed clinical evidence of infection or other inflammatory conditions were excluded. We investigated the correlation between the neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), CRP to Alb ratio (CAR) and the overall survival (OS) rates for BTC patients. Both univariate and multivariate analyses were performed to identify clinicopathological variables associated with OS. Results: The optimal cutoff level for the CAR was 0.66. An elevated CAR was associated with low OS (p<0.001). In the multivariate analysis CAR, was independently associated with OS (HR 3.44, 95% CI: 2.05-5.79, p<0.001). Median OS for CAR <= 0.66 and CAR >0.66 were 22.0 months and 6.0 months, respectively. By contrast, NLR (p=0.12) and PLR (p=0.85) were not independently associated with OS. Conclusion: The CAR might be an independent prognostic marker for patients with BTC, and might have value comparable with other established inflammation-based prognostic scores. The prognostic value of this novel inflammation-based prognostic score needs to be verified in patients with other types of cancer.Öğe Cardiac Invasion of HCC: Clinical Image(Kare Publ, 2017) Kostek, Osman; Tosun, Irem Karakaya; Tecimen, Hande; Kodal, Nil Su[Abstract Not Available]Öğe Changes in skeletal muscle area and lean body mass during pazopanib vs sunitinib therapy for metastatic renal cancer(Springer, 2019) Kostek, Osman; Yilmaz, Erdem; Hacioglu, Muhammet Bekir; Demircan, Nazim Can; Gokyer, Ali; Uzunoglu, Sernaz; Tuncbilek, NerminPurposeTo evaluate whether sunitinib and pazopanib treatments are associated with change in skeletal muscle area (SMA) and total lean body mass (LBM) as well as to compare their efficacies and safety profiles in patients with metastatic renal cell cancer (mRCC).MethodsThirty-six patients treated with a tyrosine kinase inhibitor were included. Eighteen of them received sunitinib and the rest/remaining received pazopanib in the first line of mRCC treatment. Baseline and follow-up computed tomography studies of the patients were performed to measure cross-sectional areas (cm(2)) of muscle tissues.ResultsAbout 69% of patients were male and median age was 60 (49-68)years. Median time interval between two CT imagings was 6.1 (3.1-7.7)months and it was similar between the two groups (for sunitinib, 4.9 (2.5-6.9)months vs for pazopanib, 7.3 (3.2-9.5)months, p=0.16, respectively). Disease control rate was 77.7% in all patients. Of these, 66.6% in sunitinib group was consisted of four partial responses and eight stable diseases. In addition, 88.8% in pazopanib group was consisted of three partial responses and 13 stable diseases. A significant decrease in SMA and LBM was observed after sunitinib therapy, whereas SMA and LBM values of pazopanib group did not change significantly (p=0.02 and p=0.70, respectively). No significant differences were observed between patients with sunitinib, and pazopanib group median PFS [11.9 (95% CI 6.1-17.6) vs 8.1months (95% CI 7.2-9.1), respectively; p=0.28] and median OS [28.6 (95% CI 24.3-32.9) vs 25.5months (95% CI 18.9-52.7), respectively; p=0.42]. Dose-limiting toxicities were significantly more frequent in sunitinib group than in pazopanib group (66.7% vs 22.2%, p=0.02, respectively).ConclusionsLoss of SMA and LBM with sunitinib was more substantial than with pazopanib. Treatment efficacies of both drugs were similar, but dose-limiting toxicity was more frequent in sunitinib group. Loss of SMA had no significant association with prognosis. Further studies are needed to clarify the possible association between SMA and prognosis in mRCC patients who receive sunitinib or pazopanib.Öğe Clinical features of the patient with multiple primary tumors: Single center experience(Kare Publ, 2017) Gokyer, Ali; Kostek, Osman; Hacioglu, Muhammet Bekir; Erdogan, Bulent; Kodaz, Hilmi; Turkmen, Esma; Hacibekiroglu, IlhanOBJECTIVE: Multiple primary tumors are the ones that develop in the same patient at the same or different times. They are usually examined under two groups. If the second tumor is diagnosed 6 months after the first tumor is diagnosed, it is named as metachronous tumor. If it is diagnosed in 6 months after the first diagnosis, it is called as synchronous tumor. The malignancy of tumors should be proved histologically. At least 2 cm of solid tissue should be present between two tumors. If they are at localized at the same place, a gap of at least 5 years should be present between them. Metastatic disease should be eliminated. This study aimedto review the clinical, demographic, and pathological features of multiple primary tumors, detect the prevalence, compare the results with literature findings, and evaluate and improve the approach to multiple primary tumors. METHODS: A total of 170 patients diagnosed with multiple primary tumors were included in this study. Patient data were obtained from pathology and medical reports of the patients. RESULTS: Most of the multiple primary tumors were metachronous. The number of male patients was more than that of female patients. The median time between double tumors was 3 monthsforsynchronous tumorsand 26 months for metachronous tumors. Synchronous tumors with the highest prevalence of comorbidity were lung-larynx and lung-colon, whereas metachronous tumors with the highest prevalence of comorbidity were lung-bladder, lung-larynx, breast-endometrium, and breast-colon. The history of smoking and alcohol was found to be higher in male patients andsynchronous tumors. CONCLUSION: The detection of the first tumor in the metastatic stage and an accompanying synchronous secondary tumor was found to be a poor prognostic factor. The treatment of the first tumor, smoking, squamous cell histology, and male gender were among the other factors negatively affecting survival, although they were not statistically significant.Öğe Combination of Docetaxel and Gemcitabine Ineffective in Metastatic Eccrine Porocarcinoma: A Case Report(Kare Publ, 2017) Kodaz, Hilmi; Hacioglu, Muhammet Bekir; Kostek, Osman; Erdogan, Bulent; Tastekin, Ebru; Kodaz, Cagnur Elpen; Cicin, IrfanMalignant eccrine porocarcinoma is a very rare tumor and the etiology is not known. Treatment is surgical removal of the tumor. The benefit of chemotherapy and radiotherapy is unclear. A 49-year-old male patient presented with the complaint of left inguinal swelling. Ultrasonography examination revealed 5x4 cm inguinal lymphadenopathy. The inguinal lymph nodes were excised. Pathology report indicated eccrine porocarcinoma. The patient was treated with cisplatin 40 mg/m(2) week as well as concurrent radiotherapy for 5 weeks. After 6 weeks of dual therapy, liver metastases were detected. KRAS, NRAS, and BRAF tests were negative. Gemcitabine was administered at a dose of 1000 mg/m(2) on days 1 and 8 every 21 days, and docetaxel was administered at a dose of 75 mg/m(2) on day 8, every 21 days. There was progression after 2 cycles of chemotherapy. The patient lived 7 months. In this case, use of synchronous cisplatin and radiotherapy as adjuvant treatment could not prevent tumor metastasis. The combination chemotherapy of docetaxel and gemcitabine applied after metastatic disease development was ineffective.Öğe Comparative assessment of three different second-line regimens in chemotherapy resistant / refractory small-cell lung cancer(Imprimatur Publications, 2021) Hacibekiroglu, Ilhan; Ozkul, Ozlem; Cakir, Emre; Kostek, Osman; Karatas, Fatih; Esenkaya, Asim; Demirci, AysePurpose: Small cell lung cancer (SCLC) patients unresponsive or relapsing within 90 days following frontline chemotherapy have poor prognosis and they should be treated with different chemotherapy regimens other than those used in the first-line regimen. Currently there is no globally accepted standard chemotherapeutic regimen for the treatment of these patients. This retrospective study was designed to compare CAV (Cyclophosphamide, Doxorubicin, Vincristine), weekly topotecan and weekly irinotecan regimens and to evaluate the efficacy of the three regimens in patients with chemotherapy resistant/refractory (CRR) SCLC. Methods: A total of 67 CRR-SCLC patients, who were treated with CAV, weekly topotecan and weekly irinotecan were reviewed for weekly irinotecan (27 for 60 mg/m(2) intravenously on days 1, 8 and 15 of a 28-day cycle, 24 for CAV (Cyclophosphamide 750 mg/m(2) on day 1, Doxorubicin 50 mg/m(2) on day 1 and Vincristine 1.4 mg/m(2) on day 1 every 3 weeks), 16 for weekly topotecan (4 mg/m(2) intravenously on days 1, 8 and 15 of a 28-day cycle). Results: The median follow-up time was 12.45 months, there was no difference about disease control rates (DCR) between three chemotherapy regimens (DCR; 25.9% with irinotecan, 29.2% with CAV and 31.3% with topotecan, p=0.92). Objective response rates (ORR) for irinotecan, CAV and topotecan groups were 3,7%, 8,8%, and 0%, respectively (p=0.63). Median progression free survival (PFS) and overall survival (OS) were similar according to irinotecan, CAV, and topotecan (PFS: 1.93 months, 2.30 months and 3.45 months; OS: 2.89 months, 4.79 months and 5.81 months, respectively). The adverse events were generally mild and manageable for both hematological and nonhematological toxicities in all three arms. Conclusions: Weekly irinotecan, CAV and weekly topotecan are similarly effective and safe chemotherapy protocols for the treatment of CRR-SCLC patients.Öğe Comparison of real-life data from patients with NGS panel negative and KRAS mutation positive metastatic lung adenocarcinoma(Sage Publications Ltd, 2022) Gokyer, Ali; Kucukarda, Ahmet; Kostek, Osman; Gokmen, Ivo; Ozcan, Erkan; Sayin, Sezin; Tastekin, EbruObjective: To evaluate clinical and demographic characteristics and the results of cytotoxic treatments of KRAS(G12C), KRAS(other), and next-generation sequencing (NGS) panel negative patients. Methods: NGS data of 1264 patients with non-small cell lung cancer were retrospectively evaluated. Among these patients, the mutation distributions of 1081 patients with metastatic lung adenocarcinoma were analyzed. A total of 150 patients with negative NGS panel or mutant KRAS followed up in our clinic were included. Clinical features, overall survival, first-line chemotherapy responses, and progression-free survival of NGS panel negative, KRAS(G12C), and KRAS(other) groups were compared. Results: In 1081 patients who underwent NGS from tumor tissue with the diagnosis of metastatic lung adenocarcinoma, 296 (27%) NGS panel negative and 276 (26%) KRAS mutant patients were detected. Among these patients, 150 patients whose data were available were 71 (47.3%) NGS panel negative, 54 (36%) KRAS(other), and 25 (16.7%) KRAS(G12C). Clinical features, brain metastasis, and first-line chemotherapy response were similar among groups. Bone metastases were detected more often in the NGS panel negative group (p = 0.03). The median follow-up was 8.4 months. Overall, 107 deaths had occurred at the time of analysis. There was no difference in overall survival (p = 0.56) or progression-free survival (p = 0.71) among NGS panel negative, KRAS(other), and KRAS(G12C) patients. Conclusion: There is no difference in overall survival, first-line chemotherapy response, or progression-free survival among patients with NGS panel negative, KRAS(G12C), or KRAS(other) metastatic lung adenocarcinoma. Bone metastases were observed more frequently in the NGS panel negative group.Öğe Comparison of skeletal muscle mass loss in patients with metastatic colorectal cancer treated with regorafenib or TAS-102(Imprimatur Publications, 2019) Hacioglu, Muhammet Bekir; Kostek, Osman; Kurt, Nazmi; Kucukarda, Ahmet; Gokyer, Ali; Ustabasioglu, Fethi Emre; Karatas, FatihPurpose: To assess whether regorafenib and TAS-102 treatments are associated with a change in Skeletal Muscle Area (SMA) as well as to compare Skeletal Muscle Mass (SMM) loss levels between regorafenib and TAS-102 treatments and prognostic significance in the patients with metastatic colorectal cancer (mCRC). Methods: A total of 36 mCRC patients, who received regorafenib or TAS-102 in the third-line and subsequent settings were assessed in the analysis. SMM changes were assessed with CT scans findings, and they were categorized into two groups as SMM-loss (SMM decrease >= 2%) and SMM-stable (SMM change <2%). Results: The SMM change after regorafenib therapy was significantly worse compared with TAS-102 therapy (p=0.001). The median overall survival (OS) was longer in SMM-stable group than in SMM-loss group (12.8 months; 95%CI:9.8-15.7) vs. 6.4 months; 95%CI:5.2-7.7, respectively;p=0.04). Cox regression analysis showed that SMM loss was independent prognostic indicator for OS (HR, 2.87; 95%CI: 1.07-7.42, p=0.03). Conclusion: Although patients who received regorafenib had more SMM loss than those who received TAS-102, there was no difference in OS between drugs.Öğe Contrast nephropathy in cancer patients receiving anti-VEGF therapy: a prospective study(Springer Japan Kk, 2020) Gokyer, Ali; Kucukarda, Ahmet; Kostek, Osman; Hacioglu, Muhammet Bekir; Uzunoglu, Sernaz; Kula, Osman; Kurt, NazmiObjectives Contrast nephropathy risk has been increasing in cancer patients. Nephrotoxic side effects of anti-vascular endothelial growth factor/receptor (anti-VEGF/R) drugs used in oncologic treatment are also prominent. The purpose of this study was to identify the possible association among anti-VEGF/R drugs use and development of the contrast-induced nephropathy (CIN) in patients with cancers. Methods A total of 92 patients were included in this prospective cross-sectional study. Patients whose glomerular filtration rate (GFR) of < 50 ml/min, hemoglobin of < 10 g/dl, and eastern cooperative oncology group (ECOG) score of >= 2 and had received nephrotoxic drugs were not included in the study. Blood samples were collected baseline at pre computed tomography (CT) and day 2, day 3 and day 7 later CT imaging. CIN was defined as either an increased serum creatinine value of 0.5 mg/dl or increased 25% to baseline. CIN frequency between groups receivingand not receiving anti-VEGF/R was compared using the chi-squared test. CIN frequency between bevacizumab and other anti-VEGF/R was also analyzed. Results There were 39 patients in the anti-VEGF/R (+) group and 53 patients in the anti-VEGF/R (-) group. Eleven patients (28%) in the anti-VEGF/R (+) group and 3 patients (5.6%) in the anti-VEGF/R (-) group had CIN (p = 0.006). In the anti-VEGF/R (+) group, 23 patients received bevacizumab (combined with FOLFOX/FOLFIRI), while 16 patients received other anti-VEGF/R (sunitinib, axitinib, regorafenib, aflibercept) effective treatments. CIN ratio in patients who received bevacizumab or other anti-VEGFR therapy was similar (p = 0 = 50). Of the patients, one patient had acute kidney injury leading to death. Conclusion CIN was significantly more frequent in cancer patients who receiving anti-VEGF/R drugs than those not receiving anti-VEGF/R drugs.Öğe Does celiac disease impair coronary microvascular circulation: Coronary flow velocity reserve of patients with celiac disease(Wiley, 2020) Caliskan, Zuhal; Caklili, Ozge Telci; Kahraman, Resul; Ozcan, Fatma Betul; Sayar, Suleyman; Kostek, Osman; Demircioglu, KenanBackground Celiac disease (CD) is an enteropathy characterized with immune reaction to gliadin protein. Aim In this study, we aimed to assess effect of CD on coronary microvascular circulation and the association between coronary flow velocity reserve (CFVR) and hs-CRP/Albumin ratio. Material and Methods Study was conducted between March 2017 and November 2018 with CD at Umraniye Training and Research Hospital Gastroenterology Clinic. CFVR was defined as the ratio of hyperemic to baseline diastolic peak velocities. CFVR >= 2.0 was considered normal. C-reactive protein/albumin ratio (CAR) was calculated as hs-CRP/albumin. Results Serum albumin (4.27 +/- 0.56 vs 4.50 +/- 0.34; P value: .04) level was significantly lower in celiac group but higher Hs-CRP (2.44 +/- 1.24 vs 1.82 +/- 1.29; P value < .01), hs-CRP/albumin ratio (0.57 +/- 0.30 vs 0.41 +/- 0.31; P value: .03) were recorded in celiac group. Both hyperemic flow and CFVR substantially lower in the celiac group compared to controls. In univariate analysis; age, hs-CRP, and hs-CRP/albumin ratio were associated with low CFVR and hs-CRP/albumin level was an accurate predictor of low CFVR at the ROC curve. Conclusion In this study, we found that in patients with CD, coronary flow reserve is impaired.Öğe Efficacy of regorafenib in the second-and third-line setting for patients with advanced hepatocellular carcinoma: A real life data of multicenter study from Turkey(Imprimatur Publications, 2020) Hacioglu, Muhammet Bekir; Kostek, Osman; Karabulut, Senem; Tastekin, Didem; Goksu, Sema Sezgin; Alandag, Celal; Akagunduz, BaranPurpose: After failure of the first-line sorafenib treatment in advanced or metastatic stage hepatocellular carcinoma (HCC), regorafenib is one of the newly-approved targeted agents. We aimed to evaluate the efficacy of regorafenib in patients with advanced HCC treated in the secondor third-line setting. Methods: In this retrospective and multicenter study, advanced HCC patients not eligible for local therapies, who received a secondor third-line regorafenib therapy after progression on the first-line sorafenib or sequential therapy with chemotherapy (CT) followed by sorafenib, were included. Results: In the first-line setting, 28 (28.9%) patients received CT and 69 (71.1%) patients received sorafenib. There were 24 (24.7%) patients who were intolerant to sorafenib. Disease control rate (DCR) was 53.6% for all patients treated with regorafenib, 62.3% in patients who received regorafenib in the second-line, and 32.1% for those receiving regorafenib in the third-line (p=0.007). Median progression-free survival (PFS) and overall survival (OS) were 5.6 (range; 4.3-6.9) and 8.8 (range, 6.3-11.3) months for all patients treated with regorafenib vs. 7.1 months and 10.3 months for patients who received regorafenib in the second-line vs. 5.1 and 8.7 months for patients who received regorafenib in the third-line, respectively; however, there was no statistically significant difference (p(PFS)=0.22 and p(OS)=0.85). Conclusion: Although receiving CT as a first-line therapy in advanced HCC patients did not affect the survival rates of subsequent regorafenib therapy, it might diminish the DCR of regorafenib.Öğe Enzalutamide in Prostate Cancer, A Review on Enzalutamide and cancer(Kare Publ, 2018) Erdogan, Bulent; Kostek, Osman; Bekirhacioglu, MuhammetProstate carcinoma is androgen-dependent, and therefore the main target of treatment is lowering androgen levels. Medical or surgical castration, androgen receptor-blocking agents, androgen-synthesis inhibitors, chemotherapy, sipuleucel-T, and radium-223 are treatment options. Enzalutamide is a relatively new androgen-signaling inhibitor that has 5 to 8 times greater affinity for the androgen receptor ( AR) than bicalutamide. Enzalutamide does not demonstrate agonistic activity on ARs. Enzalutamide induces apoptosis of prostate cancer cells. Enzalutamide is effective in metastatic castration-resistant prostate cancer in patients with progression after docetaxel treatment and in chemotherapy-naive patients. Enzalutamide is also superior to the commonly used AR blocking agent bicalutamide in chemotherapy-naive metastatic and non-metastatic castration-resistant prostate cancer patients. Its efficacy has been proven in hormonenaive patients, and several trials are ongoing. Enzalutamide has a favorable side effect profile and improves quality of life and pain scores. There are ongoing studies examining the efficacy and safety of enzalutamide on other several AR-expressing tumors.Öğe Factors affecting the mortality rate of patients with cancer hospitalized with COVID-19: a single center's experience(Taylor & Francis Ltd, 2021) Ayhan, Murat; Odabas, Hatice; Turan, Nedim; Ozyukseler, Deniz Tataroglu; Kostek, Osman; Alkan, Gulin; Abamor, EvrimThe main objective is to define the mortality of patients with cancer admitted to our hospital, their clinical and demographic characteristics, investigate the risk of COVID-19 for patients with cancer, and determine factors that affect the mortality rates of patients with cancer dying of COVID-19. A total of 2401 patients were admitted to our hospital with the diagnosis of COVID-19 from March 11th, 2020, to May 31st, 2020. Ninety-two out of a total of 112 cancer patients were included in this study based on the planned inclusion/exclusion criteria. The clinical, demographic, and laboratory features and treatments provided were studied, and their effect on mortality rates was analyzed. In our study the median age of the patients was 67 years, and 55.4% were male. More than half (56.5%) of our patients had metastasis. The mortality rate was 6.2% in the overall population with COVID-19, whereas it was 23.9% in patients with cancer. The mortality rate in patients with metastasis was statistically significantly higher compared with those without metastasis (34.0% vs. 10.3% P = 0.008). The mortality rate in patients still smoking was statistically significantly higher than in non-smokers (37.5% vs. 12.5% P = 0.033). The mortality rates of patients with high average C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), and D-dimer levels were statistically significantly higher than in those without, and the mortality rates of patients with lower average albumin and hemoglobin levels were statistically significantly higher than those without (P < 0.001, P = 0.006, P = 0.041, P < 0.001, P < 0.001, and P = 0.028, respectively). Having metastases concurrent with COVID-19 was a statistically significant factor predictive of prognosis. Also, high CRP, ferritin, LDH, and D-dimer, and low albumin and hemoglobin were related to increased mortality rates. The predictive and prognostic role of possible factors related to prognosis is still unknown and further large, multicenter prospective studies are needed to confirm these results.Öğe Frequency of RAS Mutations (KRAS, NRAS, HRAS) in Human Solid Cancer(Kare Publ, 2017) Kodaz, Hilmi; Kostek, Osman; Hacioglu, Muhammet Bekir; Erdogan, Bulent; Kodaz, Cagnur Elpen; Hacibekiroglu, Ilhan; Turkmen, EsmaRAS oncogene affects numerous cellular functions including growth, proliferation, apoptosis, migration, division and differentiation of the cells. It has 3 known isoforms as Harvey- RAS (HRAS), Kirsten - RAS (KRAS) and Neuroblastoma-RAS (NRAS). RAS has an intrinsic GTPase activity. It encodes proteins binding the guanine nucleotides. KRAS and HRAS were discovered in studies carried out on viruses leading to cancer. Retroviral oncogenes related to murine sarcoma virus genes (Kristen Rat Sarcoma Virus and Murine Sarcoma Virus) were discovered in 1982. These two oncogenes are similar to human KRAS. Approximately 30% of all human cancers have ras genes. Mutations in KRAS account for about 85% for all RAS mutations in human tumors, NRAS is about 11-15%, and HRAS is about 1%.Öğe Is lymph node dissection necessary for staging while undergoing nephrectomy in patients with renal cell carcinoma?(Mosby-Elsevier, 2021) Demir, Tarik; Aliyev, Altay; Besiroglu, Mehmet; Araz, Murat; Kostek, Osman; Sakin, Abdullah; Shbair, Abdallah T. M.Objective: The essential treatment for patients with renal cell carcinoma is nephrectomy. As no lymph node dissection (LND) could be performed in the majority of these patients, healthy staging could not be carried out. In this study, we investigated the impact of LND during nephrectomy on patient survival. Methods: A total of 181 patients-58 (32%) were female and 123 (68%) were male-were included in the study. Median follow-up period was 48 months. The patients were separated into 4 groups according to their stage during diagnosis; group 1 (T1-3N0M0), group 2 (T1-3NXM0), group 3 (T1-3N1M0), and group 4 (T14N0/XM1). The disease-free survival of nonmetastatic patients and the overall survival of all groups were calculated. Results: Mean age was 58.4 +/- 12.0 years. Median survival for Group 1 could not be reached. Median survival was 89 months in Group 2, 50 months in Group 3, and 39 months in Group 4 (P <0.001). There was no statistically significant difference between the N1 and M1 groups (P = 0.297). For the NX patient group without LND, median survival was 89 months, which is worse than the N0 group and better than the N1 group (P = 0.002). Conclusions: Our study presumes that the patients without LND are not staged sufficiently, NX patients have worse survival rates when compared with N0 patients, node-positive patients have poor survival rates as do the metastatic patients, and it should be defined as TNM stage4. (c) 2020 Elsevier Inc. All rights reserved.Öğe Is serum survivin expression a predictive biomarker in locally advanced gastric cancer patients treated with neoadjuvant chemotherapy?(Ios Press, 2018) Bozkaya, Yakup; Ozdemir, Nuriye Yildirim; Sezer, Sevilay; Kostek, Osman; Demirci, Nebi Serkan; Yazici, Ozan; Erdem, Gokmen UmutBACKGROUND: The potential prognostic value of survivin is variably reported depending on the gastric cancer. OBJECTIVE: Evaluation of the prognostic and predictive significance of serum survivin and its relation with survival and treatment response rates in patients with locally advanced gastric cancer (LAGC). METHODS: Serum samples were prospectively collected from 50 patients with newly diagnosed LAGC. Serum samples of 32 healthy subjects were also collected as control groups for survivin levels. Serum survivin levels were evaluated at baseline and after three cycles of neoadjuvant chemotherapy in LAGC patients. RESULTS: Median survivin level was 147 IU/L (range = 4.4-4936) at baseline and was 27 IU/L (range = 4.2-4737) after neoadjuvant chemotherapy. The difference between survivin levels of the control group (26 IU/L, range = 3.8-1430) and pretreatment patient group was statistically significant (p < 0.001). Clinical response to mDCF regimen was classified as progressive (progressive disease) and non-progressive groups (partial response + stable disease). Baseline survivin levels were similar between patients in progressive and non-progressive groups (p = 0.55). Survivin levels were significantly reduced after chemotherapy in non-progressive group (p < 0.001). In contrast, serum survivin levels increased in a stepwise fashion from baseline to post-chemotherapy in patients with progressive disease (p = 0.06). Patients were divided into low and high survivin groups according to baseline median survivin levels. Median DFS was 12.4 and 14.6 months for low and high groups, respectively (p = 0.18). Moreover, median OS was 14.4 and 24.9 months for low and high group, respectively (p = 0.14). CONCLUSION: It can be suggested that serum survivin can be used as a predictor of response to chemotherapy-but not survival-in LAGC patients receiving neoadjuvant mDCF chemotherapy. However, large multicenter prospective studies are required to confirm these results.Öğe Is the Charlson Comorbidity Index a Prognostic Indicator for Toxicity and Mortality in Elderly Patients with Locally Advanced Rectal Cancer?(Acad Medical Sciences I R Iran, 2019) Kostek, Osman; Bozkaya, Yakup; Hacioglu, Muhammet Bekir; Ozdemir, Nuriye Yildirim; Yilmaz, Erdem; Demircan, Nazim Can; Erdogan, BulentBackground: Aging is significantly related to multiple comorbidities. Even with a good performance score, some elderly patients may have poor survival outcomes. We aimed to evaluate the prognostic value of the Charlson comorbidity index (CCI) for mortality and toxicity in elderly patients with locally advanced rectal cancer (LARC). Methods: Seventy-two elderly patients with LARC who were treated with neoadjuvant chemoradiotherapy (CRT) were included. Based on their CCI score, severity of the comorbidity was categorized into 2 groups: CCI<7 and CCI >= 7. Results: The overall survival (OS) at 5 years was 54.4 percent in patients treated with neoadjuvant CRT. Median OS was not reached for all patients as well as patients with CCI score <7, but median OS was 25 (95% CI 1.0-62.1) months in patients with CCI >= 7 (P=0.002). The OS at 2 years was 79.1 percent in the patients with CCI <7 and 50.0 percent in the patients with CCI score >= 7 (P=0.002). Moreover, there was a trend toward, patients with higher CCI score who had more treatment related to grade 3 or 4 toxicity compared to those with CCI score <7 (33.3% vs 13.3%, respectively, P=0.09). Multivariable analysis indicated that the CCI score=7, presence of down-staging after therapy and clinical stage (III) independently predict mortality (HR 6.14, 95% CI 2.45-15.35, P<0.001) in patients with LARC. Conclusion: Although CCI score was not significantly associated with both toxicity and disease-free survival (DFS), we suggest that baseline CCI score might be a valuable prognostic indicator for physicians to evaluate elderly patiens with LARC for optimal treatment.Öğe Is the prognostic nutritional index a prognostic and predictive factor in metastatic non-small cell lung cancer patients treated with first-line chemotherapy?(Springer, 2020) Bozkaya, Yakup; Kostek, Osman; Sakin, Abdullah; Ozyukseler, Deniz Tataroglu; Sakalar, Teoman; Cil, IbrahimPurpose We aimed to assess the prognostic and predictive significance of pretreatment Onodera's prognostic nutritional index (OPNI) in metastatic non-small cell lung cancer patients (NSCLC) treated with first-line chemotherapy. Materials and methods Patients with metastatic NSCLC who attended five different medical oncology clinics between December 2008 and January 2018 were retrospectively analyzed. The optimal cut-off point for OPNI was performed by a receiver operating characteristic (ROC) curve analysis. Patients were assigned to either the low OPNI group or high OPNI group. Results A total of 333 patients were included in the study. Significant differences between the low and high OPNI groups were found regarding the rates of response to chemotherapy, sex, and hemoglobin level (p < 0.05). The patients in high OPNI group had a longer overall survival (OS) (15.3 vs. 10.6 months, p < 0.001) and progression-free survival (PFS) (6.7 vs. 5.3 months, p < 0.001) compared to the patients in low OPNI group. A multivariate analysis using Cox regression model revealed that a high OPNI score was an independent prognostic factor of OS (HR = 1.535, p = 0.002) and PFS (HR = 1.336, p = 0.014), but failed to demonstrate a statistical significance of pretreatment OPNI scores in predicting treatment response (p = 0.56). Conclusions Pretreatment OPNI is an independent prognostic factor for OS and PFS in metastatic NSCLC patients treated with first-line chemotherapy. Thus, it may be used as easily calculated and low-cost prognostic tool in the routine clinical practice in this patient group.