Andac Argon
Bahçeşehir University
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Featured researches published by Andac Argon.
Medical Oncology | 2005
Faruk Tas; Hasan Hansel; Ahmet Belce; Sennur Ilvan; Andac Argon; Hakan Camlica; Erkan Topuz
The present study was undertaken to evaluate the place of oxidative stress on breast cancer. Lipid peroxidation as evidenced by malondialdehyde (MDA) and the status of the antioxidants superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were estimated in tissues of 10 fibroadenoma and 40 breast cancer patients. Lipid peroxidation in breast cancer tissues was enhanced compared to nonmalignant tissues (p<0.001). Similarly, antioxidants SOD (p<0.001) and GPx (p=0.007) in tumor tissues significantly were increased. On the contrary, CAT activity was found significantly decreased (p<0.001). We found that oxidant/antioxidant status was independent from any prognostic factors concerning breast cancer. The results of our study have shown higher oxygen-free-radical production and decreased CAT activity support the oxidative stress hypothesis in breast carcinogenesis.
American Journal of Clinical Oncology | 2002
Faruk Tas; Yesim Eralp; Mert Basaran; Burak Sakar; Suleyman Alici; Andac Argon; Gulistan Bulutlar; Hakan Camlica; Adnan Aydiner; Erkan Topuz
Anemia is common in patients with cancer and is a frequent complication of myelosuppressive chemotherapy. In this study, we investigated the incidence and severity of chemotherapy-induced anemia caused by the most common chemotherapy regimens, including the new generation of chemotherapeutic agents, used in the treatment of the major nonmyeloid malignancies in adults. Five hundred fifty-two patients with histologically proven carcinoma originating from breast (n = 165), lung (n = 128), colon (n = 75), ovary (n = 84), and malignant lymphoma (n = 100) were included in this study. Hemoglobin levels for each patient were measured with an automatic counter during both pretreatment and before each chemotherapy cycle during therapy. To document the incidence of anemia, the National Cancer Institute grading system was used. Before chemotherapy, 44% of patients with breast carcinoma had anemia. There was a 16% increase in the incidence of anemia after chemotherapy. Severe anemia was observed in less than 1% of patients. No difference was found in the incidence of anemia between the fluorouracil, doxorubicin, cyclophosphamide (FAC) and cyclophosphamide, methotrexate, fluorouracil (CMF) regimens used in the adjuvant setting. However, single-agent chemotherapy with newer generation caused more anemia when compared with the FAC regimen (p < 0.005). Chemotherapy resulted in a significant decrease in hemoglobin levels when compared with pretreatment values in patients with lung cancer (p < 0.001). During treatment, the increase in the incidence of grade II anemia was associated with a parallel decrease in the incidence of grade I anemia. The incidence of severe anemia did not exceed 15%. The incidence of anemia was equivalent in both patients with small-cell lung cancer and those with non–small-cell lung cancer treated with the etoposide and cisplatin (EP) combination. Seventy-one percent of patients with colon cancer had anemia before initiation of chemotherapy. No difference was observed in posttreatment hemoglobin values compared with pretreatment values. Patients treated with irinotecan and fluorouracil and leucovorin (FUFA) combination showed similar rates of anemia. Incidence of anemia in patients with ovarian cancer at admission was 68%. Chemotherapy resulted in a prominent increase in incidence of anemia, which increased to 91.5%. There was an increase in grade II anemia, which corresponded to the decrease in grade I anemia. Less than 10% of patients developed severe anemia. No difference in the incidence of anemia was observed in patients with ovarian cancer treated with either cisplatin and cyclophosphamide or cisplatin combination. Showing a high incidence of anemia (82%) at presentation, hemoglobin levels in patients with malignant lymphoma were unaltered with chemotherapy. Severe anemia occurred in less than 3% of patients. There was a higher incidence of anemia in patients with non-Hodgkin’s lymphoma receiving the cyclophosphamide, epirubicin, vincristine, prednisone (CEOP) regimen in contrast to patients with Hodgkin’s lymphoma treated with the doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) combination. There was a prominent decline in the hemoglobin levels with cisplatin-based combinations in contrast to combinations including noncisplatin agents (p < 0.001). In this study, we have observed equivalent rates of treatment-related anemia when compared with previous data in patients with specific tumor types. The incidence of pretreatment anemia was high in various malignancies. The mechanisms underlying the propensity for a higher risk of pretreatment anemia in patients with malignant disorders and its influence on the outcome has to be elucidated by further population-based and molecular studies.
American Journal of Clinical Oncology | 2004
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.
Melanoma Research | 2004
Faruk Tas; Derya Duranyildiz; Andac Argon; Oguz H; Hakan Camlica; Yasasever; Erkan Topuz
This study was conducted to investigate the serum levels of bcl-2 and survivin in patients with melanoma and the relationship with tumour progression and known prognostic parameters. Forty-four patients with cutaneous melanoma were investigated. Serum samples were obtained on first admission before adjuvant and metastatic treatment were given and at follow-up. Serum bcl-2 and survivin levels were determined using enzyme immunometric assay (EIA) and enzyme-linked immunosorbent assay (ELISA). The baseline serum bcl-2 levels were significantly higher in patients with melanoma than in the control group (P=0.01). For the serum survivin levels, no difference was found (P=0.6). No significant correlations were found between the prognostic parameters analysed and the serum survivin concentrations. The same was true of the serum bcl-2 values, except for the age of the patient (P=0.025) and nodal involvement (P=0.003). No significant relationship was found between the serum levels of bcl-2 and survivin (r=−0.13, P=0.4). In node-positive patients (n=8) both of these anti-apoptotic substances were unchanged after interferon-alpha-2b therapy. However, serum survivin concentrations were significantly increased in 10 patients with metastatic melanoma who underwent dacarbazine (DTIC)-based cytotoxic chemotherapy (P=0.047). A similar finding was not determined for the serum bcl-2 levels. In conclusion, the results of this study suggest that decreased apoptosis is associated partly with an increase in serum bcl-2. However, much research continues in this field, and exciting new knowledge will ultimately emerge.
American Journal of Clinical Oncology | 2002
Erkan Topuz; Mert Basaran; Pinar Saip; Adnan Aydiner; Andac Argon; Burak Sakar; Faruk Tas; Kazim Uygun; Dursun Bugra; N. Faruk Aykan
Gastric carcinoma remains one of the leading causes of cancer-related death in the world. Clinical studies have revealed that approximately two thirds of the patients seek treatment for early recurrence within the abdominal cavity. The aim of this phase II study was to evaluate the toxicity, feasibility, and efficacy of adjuvant intraperitoneal chemotherapy (IPCT) with cisplatin, mitoxantrone, 5-fluorouracil (5-FU), and folinic acid in patients with stage II-III gastric cancer. Patients with stage II and III gastric cancer aged between 15 and 70 years, after curative resection, with adequate liver, renal, and cardiac function were included in the study. The chemotherapy regimen consisted of cisplatin 60 mg/m2, mitoxantrone 12 mg/m2, 5-FU 600 mg/m2, and folinic acid 60 mg/m2, delivered intraperitoneally, diluted in 2 l normal saline. Intraperitoneal fluid was not drained. Each course of IPCT was repeated every 4 weeks for a total 6 cycles. Thirty-nine patients were enrolled in the study. Twenty-eight of the 39 patients (71.8%) completed six courses of the planned schedule. One patient (2.6%) died after a fourth cycle of IPCT from an undetermined reason. The major nonhematologic toxicity from IPCT was grade I-III nausea and/or vomiting experienced by 27 patients (69.2%). Twenty-four (61.5%) patients reported abdominal discomfort. Median follow-up was 23 (range: 3–105) months. Twenty-five patients (64.1%) were dead. Median disease-free survival and overall survival were 12 (CI 95%; 8.3–15.7 months) and 19 months (CI 95%; 10.5–27.5 months), respectively. The cumulative 5-year disease-free survival and overall survival were 24.7% and 30.7%, respectively. The regimen was generally associated with acceptable toxicity. However, adjuvant IPCT has similar survival rates in comparison to no adjuvant treatment; thus, it cannot be currently recommended outside the context of a clinical trial.
Melanoma Research | 2005
Faruk Tas; Andac Argon; Hakan Camlica; Erkan Topuz
The present study was designed to assess the efficacy and safety of combination therapy with temozolomide plus cisplatin in patients with metastatic melanoma. Thirty patients with metastatic melanoma were enrolled. Treatment consisted of intravenous cisplatin (75 mg/m2) on day 1 and oral temozolomide (200 mg/m2) on days 1 to 5, every 4 weeks. Nine patients (30.0%) achieved an objective response, including two complete (6.7%) and seven partial (23.3%) responses. The median response duration was 161 days. The median progression-free and overall survival times were 72 and 120 days, respectively. Myelosuppression and emesis were the primary toxicities. In conclusion, temozolomide combined with cisplatin is an active and safe first-line chemotherapy regimen with acceptable and easily manageable toxicities in patients with metastatic melanoma.
Japanese Journal of Clinical Oncology | 2004
Andac Argon; Mert Basaran; Fulya Yaman; Yavuz Dizdar; Burak Sakar; Hakan Camlica; Sevil Bavbek; Harzem Ozger; Emin Darendeliler; Haluk Onat
Tohoku Journal of Experimental Medicine | 2002
Suleyman Alici; Yesim Eralp; Pinar Saip; Andac Argon; Mert Basaran; Erkan Topuz; Adnan Aydiner
Medical Oncology | 2008
Gonca Gokdemir; Andac Argon; Damlanur Sakiz; Dilek Argon; Adem Koslu
International Journal of Clinical and Experimental Pathology | 2015
Yalcin Cirak; Yavuz Furuncuoglu; Ozlem Yapicier; Suleyman Alici; Andac Argon