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Featured researches published by Zeki Ustuner.


Acta Oncologica | 2005

The prevalence and determinants of the use of complementary and alternative medicine in adult Turkish cancer patients.

Faruk Tas; Zeki Ustuner; Gulbeyaz Can; Yesim Eralp; Hakan Camlica; Mert Basaran; Hakan Karagol; Burak Sakar; Rian Disci; Erkan Topuz

A study was undertaken to analyze the extent of using complementary alternative medicine (CAM) and to compare sociodemographic and medical characteristics of users and non-users of CAM in Turkish oncology patients. A total of 615 patients with cancer who attended ambulatory patient care units answered the questionnaires. Medical information was reviewed from chart data. Some 291 patients (47.3%) had used at least one type of CAM since the time of initial diagnosis. CAMs almost always consisted of herbal agents (95%). Nettle (Urticae herba) used in conjunction with (88%) or without (56%) various herbal agents were the most popular and prominent CAMs used by patients. Univariate and multivariate comparisons of users and non-users of CAM were performed. In multivariate analysis, female sex (p=0.0006), high income (p=0.0008), advanced stage at diagnosis (p=0.02), and usage of multiple chemotherapy applications (p=0.03) were determined as independent factors for CAM use.


American Journal of Clinical Oncology | 2004

Timing of Death From Tumor Recurrence After Curative Gastrectomy for Gastric Cancer

Burak Sakar; Hakan Karagol; Mahmut Gumus; Mert Basaran; Esra Kaytan; Andac Argon; Zeki Ustuner; Sevil Bavbek; Dursun Bugra; Faruk Aykan

In Western literature, there are few studies investigating the predictors of early versus late recurrence after curative gastrectomy for gastric cancer. The current study analyzed (1) patients who died of recurrent gastric cancer and (2) prognostic factors, which can be applied to timing of death from tumor recurrence. Of 492 patients who underwent curative resection (R0) for gastric cancer in the Department of Surgery, Medical Faculty of Istanbul between 1994 and 2000, 142 patients who died of recurrence were included into study. None of the patients had received postoperative adjuvant treatment. The patients were divided into 2 groups: an early recurrence group that included 102 patients who recurred and died within 2 years after surgery, and a late recurrence group, which included 40 patients who died of recurrence more than 2 years after surgery. Clinicopathologic findings were compared between the early and late recurrence groups. Multivariate analysis was performed to investigate the independent factors, which are predictive for early versus late recurrence, and prognostic factors independently associated with the survival period. In multivariate analysis, the early recurrence group, when compared with the late recurrence group, was characterized by lymph node metastasis (N1-3 versus N0; P = 0.002). Overall survival was influenced by nodal status (N1-3 versus N0; P = 0.003), type of operation performed (radical total versus radical subtotal gastrectomy; P = 0.003), Eastern Cooperative Oncology Group performance status (PS 3–4 versus PS 1–2; P = 0.004), and tumor localization (cardia versus corpus and antrum; P = 0.046). In contrast, T stage of the disease was not prognostic for survival, although it was close to statistical significance (P = 0.066). Multivariate analysis showed that poorer performance status at initial presentation (P = 0.001) and lymph node metastasis (P = 0.032) independently correlated with overall survival (P = 0.002). Lymph node status was the most important factor predictive for early versus late recurrence and patients with lymph node metastases were at more risk of death within 2 years after curative operation for gastric cancer. Postoperative chemoradiotherapy should be especially recommended for patients at high risk of recurrence of adenocarcinoma of the stomach or who have undergone curative resection.


American Journal of Clinical Oncology | 2004

Prognostic features and survival of inoperable hepatocellular carcinoma in Turkish patients with cirrhosis

Burak Sakar; Zeki Ustuner; Hakan Karagol; Gorkem Aksu; Hakan Camlica; N. Faruk Aykan

Background:Primary hepatocellular carcinoma (HCC) is common in Turkey and its prognosis is poor. In the current study the authors analyzed the prognostic factors and survival in Turkish patients with inoperable HCC with cirrhosis. Methods:Clinical and demographic data of 91 patients consecutively admitted to the authors’ institute from 1988 to 2000 were reviewed. A univariate analysis was performed using the Kaplan–Meier method to identify predictors of survival and were compared using the Mantel log-rank test. Independent factors correlated with survival were determined using the Cox regression analysis. Results:Cirrhosis was diagnosed in all patients. Coinfections with HCV and HBV were not observed. Overall median survival was 16.9 months. On univariate analysis, poor performance status (Eastern Cooperative Group); high α-fetoprotein (AFP); low albumin; high bilirubin; high alkaline phosphatase; high lactic dehydrogenase; high alanine and aspartate aminotransferase; high γ-glutamyl transpeptidase; high platelet count; low prothrombin activity; hepatitis B surface antigen positivity; the presence of ascites, encephalopathy, and portal vein thrombosis; poor differentiation and diffuse type of tumor; and no treatment were associated with shorter survival. Multivariate analysis showed that only independent risk factors were related to performance status (Eastern Cooperative Group) at initial presentation and with pathologic characteristic of the tumor: abnormal AFP level. Conclusion:HCC occurred only in patients with liver cirrhosis. Survival time can be predicted from information collected by the physician at the initial assessment.


Medical Oncology | 2004

Second-Line docetaxel and gemcitabine combination chemotherapy in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy: a phase II trial.

Faruk Tas; Cumhur Demir; Hakan Camlica; Zeki Ustuner; Erkan Topuz

Docetaxel has been the only single active agent against chemotherapy-pretreated non-small-cell lung cancer (NSCLC). The purpose of this phase II study was to evaluate the efficacy and safety of docetaxel combined with gemcitabine, another effective drug, in patients with NSCLC previously treated with platinum-based chemotherapy. Thirty-three patients were enrolled. Prior chemotherapy was cisplatin combined with etoposide in 24 patients and vinorelbine in 9 patients. Tumors were sensitive (n=15), resistant (n=9), and refractory (n=9) to front-line chemotherapy. Treatment was docetaxel 85 mg/m2 on d 1, and gemcitabine 1200 mg/m2 on d 1 and 8, with cycles repeated every three weeks. Ten patients (30.3%, 95% CI: 15.6–48.7) achieved a partial response and 15 (45.5%) stable disease. Responses were similar frequencies in platinum-sensitive and platinum-resistant/refractory tumors. With a median follow-up period of 5.7 mo (range 1.6–20.0), the median and 6-mo event-free survival were 5.5 mo, 40.6%, respectively. Median and 6-mo over-all survival were 7.3 mo and 52.7%. Patients with progressive disease to chemotherapy (p=0.0008), higher LDH (p=0.005), and NSE levels (p=0.03) survived shorter than other patients. In patients refractory to prior chemotherapy, survival was poor as borderline significantly (p=0.06). The major hematological toxicity was neutropenia. Grade III–IV neutropenia was noted in 14 (42%) patients, with three episodes of febrile neutropenia in 111 cycles. Docetaxel combined with gemcitabine is an active and safe second-line therapy for patients with NSCLC.


Turkish Journal of Medical Sciences | 2017

A new angiogenesis prognostic index with VEGFA, PlGF, and angiopoietin1 predicts survival in patients with advanced gastric cancer

Sedef Hande Aktaş; Hakan Akbulut; Ozan Yazici; Nurullah Zengin; Halime Nalan Akgün; Zeki Ustuner; Fikri Icli

BACKGROUND/AIM The role of angiogenic factors in gastric cancer is not clear. We aimed to assess the role of vascular endothelial growth factor A (VEGFA), angiopoietin 1 (Ang-1), and placental growth factor (PlGF) in the prognosis of patients with advanced gastric cancer. MATERIALS AND METHODS Thirty consecutive patients treated with a modified DCF (docetaxel, cisplatin, and fluorouracil) regimen were included in the study. The plasma VEGFA, Ang-1, and PlGF levels of the patients before treatment and following two cycles of chemotherapy were measured and evaluated as prognostic factors. RESULTS Poor performance status and lower Ang-1 levels were correlated with poor overall survival (OS). No significant correlation between VEGFA or PlGF and OS was found. An angiogenesis prognostic index (API) based on the levels of VEGFA, Ang-1, and PlGF was found to be highly correlated with OS. Performance status and API were found as independent prognostic factors for OS. Furthermore, a decrease in VEGFA by 25% from the pretreatment level was also found as a prognostic factor for OS independent of response to DCF regimen. CONCLUSION Our results support the use of the new API including VEGFA, Ang-1, and PlGF levels in patients with advanced gastric cancer as a predictor of survival.


Journal of Clinical Oncology | 2010

Association between glutathione s-transferase P1 polymorphisms and time to tumor progression in small cell lung cancer patients.

Pinar Saip; F. Sen; B. Vural; E. Ugurel; A. Demirkan; D. Derin; Yesim Eralp; H. Camlica; Zeki Ustuner; U. Ozbek

e12041 Background: Many of commonly used chemotherapeutics in lung cancer treatment are metabolized by glutathione-S transferases (GST). Placental isoform of GST (GSTP1) is the most abundant isoform in the lung. Polymorphisms within the GSTP1 may result in alterations in enzyme activity and change sensitivity to platinum based chemotherapy. We investigated whether the polymorphism within the exon 5 and exon 6 of GSTP1 gene may change response to therapy, time to tumor progression (TTP) and overall survival in small cell lung cancer (SCLC) patients. Methods: Ninety four histologically confirmed patients with SCLC were enrolled in this study during 1995-2006. GSTP1 Ile105Val polymorphism in exon 5 and GSTP1 Ala114Val polymorphism in exon 6 were determined by using PCR-RFLP techniques. Associations between the GSTP1 polymorphisms and treatment response were evaluated using the chi-square tests. Associations between the GSTP1 polymorphisms and TTP and overall survival were compared using Kaplan-Meier survival...


Medical Oncology | 2008

Prognostic and predictive value of vascular endothelial growth factor and its soluble receptors, VEGFR-1 and VEGFR-2 levels in the sera of small cell lung cancer patients

Zeki Ustuner; Pinar Saip; Vildan Yasasever; Burçak Vural; Aziz Yazar; Cengiz Bal; Betul Ozturk; Ugur Ozbek; Erkan Topuz


Skull Base Surgery | 2004

Skull Base Plasmacytoma in a Patient with Light Chain Myeloma

Zeki Ustuner; Mert Basaran; Talat Kırış; Bilge Bilgic; Serra Sencer; Burak Sakar; Yavuz Dizdar; Sevil Bavbek; Haluk Onat


American Journal of Clinical Oncology | 2004

Clinical Value of Protein S100 and Melanoma-Inhibitory Activity (MIA) in Malignant Melanoma

Faruk Tas; Vildan Yasasever; Derya Duranyildiz; Hakan Camlica; Zeki Ustuner; Adnan Aydiner; Erkan Topuz


Breast Cancer | 2015

Nine weeks versus 1 year adjuvant trastuzumab in patients with early breast cancer: an observational study by the Turkish Oncology Group (TOG)

Fikri Icli; Kadri Altundag; Hakan Akbulut; Semra Paydas; Gul Basaran; Pinar Saip; Gamze Gokoz Dogu; Yesim Eralp; Ruchan Uslu; Alper Sevinc; Handan Onur; Nil Molinas Mandel; Canfeza Sezgin; Mustafa Altinbas; Nilüfer Güler; Abdurrahman Isikdogan; Erhan Gokmen; Kazim Uygun; Zeki Ustuner; Arzu Yaren; Binnaz Demirkan; Ugur Coskun; Alper Ata; Metin Ozkan; Ali Arican

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