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Öğe The clinical and pathological features of 133 colorectal cancer patients with brain metastasis: a multicenter retrospective analysis of the Gastrointestinal Tumors Working Committee of the Turkish Oncology Group (TOG)(Humana Press Inc, 2014) Tanriverdi, Ozgur; Kaytan-Saglam, Esra; Ulger, Sukran; Bayoglu, Ibrahim Vedat; Turker, Ibrahim; Ozturk-Topcu, Turkan; Cokmert, Suna; Turhal, Serdar; Oktay, Esin; Karabulut, Bulent; Kilic, Diclehan; Kucukzeybek, Yuksel; Oksuzoglu, Berna; Meydan, Nezih; Kaya, Vildan; Akman, Tulay; Ibis, Kamuran; Saynak, Mert; Sen, Cenk Ahmet; Uysal-Sonmez, Ozlem; Pilanci, Kezban Nur; Demir, Gokhan; Saglam, Sezer; Kocar, Muharrem; Menekse, Serkan; Goksel, Gamze; Yapar-Taskoylu, Burcu; Yaren, Arzu; Uyeturk, Ummugul; Avci, Nilufer; Denizli, Bengu; Ilis-Temiz, EsraBrain metastasis in colorectal cancer is highly rare. In the present study, we aimed to determine the frequency of brain metastasis in colorectal cancer patients and to establish prognostic characteristics of colorectal cancer patients with brain metastasis. In this cross-sectional study, the medical files of colorectal cancer patients with brain metastases who were definitely diagnosed by histopathologically were retrospectively reviewed. Brain metastasis was detected in 2.7 % (n = 133) of 4,864 colorectal cancer patients. The majority of cases were male (53 %), older than 65 years (59 %), with rectum cancer (56 %), a poorly differentiated tumor (70 %); had adenocarcinoma histology (97 %), and metachronous metastasis (86 %); received chemotherapy at least once for metastatic disease before brain metastasis developed (72 %), had progression with lung metastasis before (51 %), and 26 % (n = 31) of patients with extracranial disease at time the diagnosis of brain metastasis had both lung and bone metastases. The mean follow-up duration was 51 months (range 5-92), and the mean survival was 25.8 months (95 % CI 20.4-29.3). Overall survival rates were 81 % in the first year, 42.3 % in the third year, and 15.7 % in the fifth year. In multiple variable analysis, the most important independent risk factor for overall survival was determined as the presence of lung metastasis (HR 1.43, 95 % CI 1.27-4.14; P = 0.012). Brain metastasis develops late in the period of colorectal cancer and prognosis in these patients is poor. However, early screening of brain metastases in patients with lung metastasis may improve survival outcomes with new treatment modalities.Öğe Oxytocin Improves Follicular Reserve in a Cisplatin-Induced Gonadotoxicity Model in Rats(Hindawi Ltd, 2014) Erbas, Oytun; Akman, Levent; Yavasoglu, Altug; Terek, Mustafa Cosan; Akman, Tulay; Taskiran, DilekCisplatin (CP), an antitumor agent, has been shown to cause ovarian injury and dysfunction in both animal and human studies. The present study was conducted to investigate the protective effect of oxytocin (OT) on CP-induced ovarian toxicity in rats. Twenty-one adult female rats were included in the study. Fourteen rats were administered intraperitoneally CP (2mg/kg/day) twice a week for 5 weeks. Control group (n = 7) did not receive any treatment. Following treatment, CP-received rats were randomly divided into two groups and treated with either saline (1 mL/kg/day, n = 7) or OT (160 mu g/kg/day, n = 7) for 5 weeks. Then, ovarian toxicity and effects of OT were evaluated by histomorphological and biochemical analysis. Our findings revealed a significant reduction in the number of follicles at each grade in saline-treated group. AMH level was significantly lower in saline group compared to control (P < 0.0005). OT treatment significantly attenuated CP toxicity in ovaries and increased AMH levels compared to saline group (P < 0.005). Also, administration of OT lessened lipid peroxidation and prevented glutathione depletion in CP-treated rats (P < 0.05). These results indicated that OT could lessen the CP-induced ovarian damage and improve follicular reserve by preventing oxidative damage.Öğe Prevention of Pazopanib-Induced Prolonged Cardiac Repolarization and Proarrhythmic Effects(Arquivos Brasileiros Cardiologia, 2014) Akman, Tulay; Erbas, Oytun; Akman, Levent; Yilmaz, Ahmet U.Background: Pazopanib (PZP) may induce prolonged cardiac repolarization and proarrhythmic effects, similarly to other tyrosine kinase inhibitors. Objectives: To demonstrate PZP-induced prolonged cardiac repolarization and proarrhythmic electrophysiological effects and to investigate possible preventive effects of metoprolol and diltiazem on ECG changes (prolonged QT) in an experimental rat model. Methods: Twenty-four Sprague-Dawley adult male rats were randomly assigned to 4 groups (n = 6). The first group (normal group) received 4 mL of tap water and the other groups received 100 mg/kg of PZP (Votrient (R) tablet) perorally, via orogastric tubes. After 3 hours, the following solutions were intraperitoneally administered to the animals: physiological saline solution (SP), to the normal group and to the second group (control-PZP+SP group); 1 mg/kg metoprolol (Beloc, Ampule, AstraZeneca), to the third group (PZP+metoprolol group); and 1 mg/kg diltiazem (Diltiazem, Mustafa Nevzat), to the fourth group (PZP+diltiazem group). One hour after, and under anesthesia, QTc was calculated by recording ECG on lead I. Results: The mean QTc interval values were as follows: normal group, 99.93 +/- 3.62 ms; control-PZP+SP group, 131.23 +/- 12.21 ms; PZP+metoprolol group, 89.36 +/- 3.61 ms; and PZP+diltiazem group, 88.86 +/- 4.04 ms. Both PZP+metoprolol and PZP+diltiazem groups had significantly shorter QTc intervals compared to the control-PZP+SP group (p < 0.001). Conclusion: Both metoprolol and diltiazem prevented PZP-induced QT interval prolongation. These drugs may provide a promising prophylactic strategy for the prolonged QTc interval associated with tyrosine kinase inhibitor use.Öğe The Preventive Effect of Oxytocin to Cisplatin-Induced Neurotoxicity: An Experimental Rat Model(Hindawi Publishing Corporation, 2015) Akman, Tulay; Akman, Levent; Erbas, Oytun; Terek, Mustafa Cosan; Taskiran, Dilek; Ozsaran, AydinPeripheral neurotoxicity is a frequent dose-limiting side effect of the chemotherapeutic agent cisplatin. This study was conducted to investigate the preventive effect of oxytocin (OT) on cisplatin-induced neurotoxicity in rats. Forty-four adult female rats were included in the study. Thirty-six rats were administered intraperitoneally (i.p.) single dose cisplatin 10mg/kg and divided in to 3 groups. The first group (n = 12) received saline i.p whereas the second group (n = 12) and the third group (n = 12) were injected with 80 mu g/kg and 160 mu g/kg OT, respectively, for 10 days. The remaining 8 rats served as the control group. Electromyography (EMG) studies were recorded and blood samples were collected for the measurement of plasma lipid peroxidation (malondialdehyde; MDA), tumor necrosis factor (TNF)-alpha and glutathione (GSH) levels. EMG findings revealed that compound muscle action potential amplitude was significantly decreased and distal latency was prolonged in the nontreated cisplatin-injected rats compared with the control group (P < 0.005). Also, nontreated cisplatin-injected rats showed significantly higher TNF-alpha and MDA levels and lower GSH level than control group. The administration of OT significantly ameliorated the EMG alterations, suppressed oxidative stress and inflammatory parameters, and increased antioxidative capacity. We suggest that oxytocin may have beneficial effects against cisplatin-induced neurotoxicity.Öğe Prognostic factors for survival in metastatic renal cell carcinoma patients with brain metastases receiving targeted therapy(Sage Publications Ltd, 2018) Yildiz, Ibrahim; Bilici, Ahmet; Karadurmus, Nuri; Ozer, Leyla; Tural, Deniz; Kaplan, Mehmet A.; Akman, Tulay; Bayoglu, Ibrahim, V; Uysal, Mukremin; Yildiz, Yasar; Tanriverdi, Ozgur; Yazici, Ozan; Surmeli, Zeki; Turhal, Nazim Serdar; Bavbek, Sevil; Selcukbiricik, Fatih; Koca, Dogan; Basaran, MertBackground: The primary objective of our study was to examine the clinical outcomes and prognosis of patients with metastatic renal cell carcinoma (mRCC) with brain metastases (BMs) receiving targeted therapy. Patients and methods: Fifty-eight patients from 16 oncology centers for whom complete clinical data were available were retrospectively reviewed. Results: The median age was 57 years (range 30-80). Most patients underwent a nephrectomy (n = 41; 70.7%), were male (n = 42; 72.4%) and had clear-cell (CC) RCC (n = 51; 87.9%). Patients were treated with first-line suni-tinib (n = 45; 77.6%) or pazopanib (n = 13; 22.4%). The median time from the initial RCC diagnosis to the diagnosis of BMs was 9 months. The median time from the first occurrence of metastasis to the development of BMs was 7 months. The median overall survival (OS) of mRCC patients with BMs was 13 months. Time from the initial diagnosis of systemic metastasis to the development of BMs (<12 months; p = 0.001), histological subtype (non-CC; p<0.05) and number of BMs (>2; p<0.05) were significantly associated with OS in multivariate analysis. There were no cases of toxic death. One mRCC patient with BMs (1.7%) experienced treatment-related cerebral necrosis. All other toxicities included those commonly observed with VEGF-TKI therapy. Conclusions: The time from the initial diagnosis of systemic metastasis to the development of BMs (<12 months), a non-CC histological subtype, and a greater number of BMs (>2) were independent risk factors for a poor prognosis.Öğe Sunitinib for Patients with Metastatic Non-clear Cell Renal Cell Carcinoma: A Multicenter Retrospective Turkish Oncology Group Trial(Int Inst Anticancer Research, 2014) Yildiz, Ibrahim; Ekenel, Meltem; Akman, Tulay; Kocar, Muharrem; Uysal, Mukremin; Kanitez, Metin; Varol, Umut; Bayoglu, Ibrahim Vedat; Tural, Deniz; Kaplan, Mehmet Ali; Avci, Nilufer; Surmeli, Zeki; Dede, Isa; Ulas, Arife; Yazici, Ozan; Basaran, MertAim: This study aimed to assess the clinical efficacy and toxicity of sunitinib, a targeted-agent, for non-clear cell renal cell carcinoma. Patients and Methods: Sixty-three patients with complete clinical data from 13 oncology Centers were retrospectively evaluated. Outcomes analyzed were objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and adverse events. Results: The median age of all patients, 38 men (60.3%) and 25 women (39.7%), was 63 years (range=25-82 years). Histological subtypes included 46 (88%) cases of papillary RCC, 10 of chromophobe, and 7 unclassified cases. Median treatment duration was seven months (range=2-86 months). At the time of this analysis, 52 patients had discontinued treatment, 33 of whom had died. Treatment discontinuation was due to disease progression in 43 patients, and toxicity in nine. Dose interruption was necessary in 22 (34.9%) patients, and dose reduction in 27 (42.9%). The objective response rate and disease control rate were 11.1% and 63.5%, respectively. The median PFS and OS were 7.6 months (95% confidence interval (CI)=5.5-9.7 months) and 22.0 months (95% CI=13.4-30.6 months), respectively, with 1-year rates of 64.7% and 33.7%, respectively. Conclusion: Clinical outcome of the metastatic non-clear cell RCC patients with sunitinib treatment seemed to be worse than the historical data of clear cell RCC patients, in terms of PFS, OS and objective response. New and more effective targeted-therapies and better understanding of the underlying molecular processes are necessary to improve survival outcome for these patients.Öğe Therapeutic effect of sunitinib on diabetes mellitus related ovarian injury: an experimental rat model study(Taylor & Francis Ltd, 2015) Erbas, Oytun; Pala, Halil Gursoy; Pala, Emel Ebru; Ulkumen, Burcu Artunc; Akman, Levent; Akman, Tulay; Oltulu, Fatih; Aktug, Huseyhz; Yavasoglu, AltugThe aim of our study is to investigate the effect of sunitinib on diabetes mellitus related-ovarian injury and fibrosis in rat models. An experimental diabetes mellitus model was created in 16 rats, and eight rats with normal blood glucose levels were included in control group (Group-1). The diabetic rats were divided into two groups:diabetic control group (water given) - Group-2 and sunitinib treatment group - Group-3. After four weeks, bilateral oophorectomy was performed and ovaries were examined histologically. The groups were compared by Student's t-test, analysis of variance (ANOVA) and Mann Whitney's U-test. There was a significant increase in no-medication (water given) diabetic rat's ovary (Group-2) in terms of follicular degeneration, stromal degeneration, stromal fibrosis and NF-kappaB immune-expression compared with control group normal rats' ovary (Group-1) (p < 0.0001). Stromal degeneration (p = 0.04), stromal fibrosis (p = 0.01), follicular degeneration (p = 0.02), NF-kappaB immune-expression (p = 0.001) significantly decreased in sunitinib-treated diabetic rat's ovary (Group-3) when compared with no-medication (water given) diabetic rat's ovary (Group-2) (p < 0.05). When we used sunitinib in the treatment of diabetic rats, ovarian injury, fibrosis and NF-kappaB immunoexpression decreased significantly. The effects of sunitinib in rat models give hope to the improved treatment of premature ovarian failure due to diabetes mellitus in humans.Öğe Therapeutic effect of sunitinib on diabetes mellitus related ovarian injury: an experimental rat model study(Taylor & Francis Ltd, 2015) Erbas, Oytun; Pala, Halil Gursoy; Pala, Emel Ebru; Ulkumen, Burcu Artunc; Akman, Levent; Akman, Tulay; Oltulu, Fatih; Aktug, Huseyhz; Yavasoglu, AltugThe aim of our study is to investigate the effect of sunitinib on diabetes mellitus related-ovarian injury and fibrosis in rat models. An experimental diabetes mellitus model was created in 16 rats, and eight rats with normal blood glucose levels were included in control group (Group-1). The diabetic rats were divided into two groups:diabetic control group (water given) - Group-2 and sunitinib treatment group - Group-3. After four weeks, bilateral oophorectomy was performed and ovaries were examined histologically. The groups were compared by Student's t-test, analysis of variance (ANOVA) and Mann Whitney's U-test. There was a significant increase in no-medication (water given) diabetic rat's ovary (Group-2) in terms of follicular degeneration, stromal degeneration, stromal fibrosis and NF-kappaB immune-expression compared with control group normal rats' ovary (Group-1) (p < 0.0001). Stromal degeneration (p = 0.04), stromal fibrosis (p = 0.01), follicular degeneration (p = 0.02), NF-kappaB immune-expression (p = 0.001) significantly decreased in sunitinib-treated diabetic rat's ovary (Group-3) when compared with no-medication (water given) diabetic rat's ovary (Group-2) (p < 0.05). When we used sunitinib in the treatment of diabetic rats, ovarian injury, fibrosis and NF-kappaB immunoexpression decreased significantly. The effects of sunitinib in rat models give hope to the improved treatment of premature ovarian failure due to diabetes mellitus in humans.Öğe Therapeutic effect of sunitinib on diabetes mellitus related ovarian injury: an experimental rat model study(Taylor & Francis Ltd, 2015) Erbas, Oytun; Pala, Halil Gursoy; Pala, Emel Ebru; Ulkumen, Burcu Artunc; Akman, Levent; Akman, Tulay; Oltulu, Fatih; Aktug, Huseyhz; Yavasoglu, AltugThe aim of our study is to investigate the effect of sunitinib on diabetes mellitus related-ovarian injury and fibrosis in rat models. An experimental diabetes mellitus model was created in 16 rats, and eight rats with normal blood glucose levels were included in control group (Group-1). The diabetic rats were divided into two groups:diabetic control group (water given) - Group-2 and sunitinib treatment group - Group-3. After four weeks, bilateral oophorectomy was performed and ovaries were examined histologically. The groups were compared by Student's t-test, analysis of variance (ANOVA) and Mann Whitney's U-test. There was a significant increase in no-medication (water given) diabetic rat's ovary (Group-2) in terms of follicular degeneration, stromal degeneration, stromal fibrosis and NF-kappaB immune-expression compared with control group normal rats' ovary (Group-1) (p < 0.0001). Stromal degeneration (p = 0.04), stromal fibrosis (p = 0.01), follicular degeneration (p = 0.02), NF-kappaB immune-expression (p = 0.001) significantly decreased in sunitinib-treated diabetic rat's ovary (Group-3) when compared with no-medication (water given) diabetic rat's ovary (Group-2) (p < 0.05). When we used sunitinib in the treatment of diabetic rats, ovarian injury, fibrosis and NF-kappaB immunoexpression decreased significantly. The effects of sunitinib in rat models give hope to the improved treatment of premature ovarian failure due to diabetes mellitus in humans.
