Zafer Akcali
Başkent University
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Publication
Featured researches published by Zafer Akcali.
American Journal of Clinical Pathology | 2004
Özdemir Bh; Zafer Akcali; Mehmet Haberal
Our aim was to study the effect of hypercholesterolemia on angiogenesis induced by breast carcinoma. Of 51 patients with invasive ductal carcinoma, 28 had hypercholesterolemia and 23 had normocholesterolemia. The intratumoral microvessel density (MVD) was evaluated by using anti-CD31 antibody. The expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) on endothelial and tumor cells was examined and graded semiquantitatively. Patients with normocholesterolemia had a higher MVD (76.4 +/- 8.2) than those with hypercholesterolemia (54.6 +/- 5.1) (P < .01). The risks of recurrence and distant metastasis were higher in patients with normocholesterolemia than in patients with hypercholesterolemia (P < .01). Patients with hypercholesterolemia showed lower expression of endothelial VEGF and bFGF than patients with normocholesterolemia (P < .05 and P < .01, respectively). In addition, tumoral bFGF and VEGF expression showed negative correlation with the presence of hypercholesterolemia (P < .01). We suggest that hypercholesterolemia impairs angiogenesis by suppressing endothelial and tumoral bFGF and VEGF expression and, therefore, lowers the risk of metastases in cases of invasive breast carcinoma.
Journal of Experimental & Clinical Cancer Research | 2009
Zuleyha Calikusu; Yesim Yildirim; Zafer Akcali; Hakan Sakalli; Nebil Bal; Ilker Unal; Ozgur Ozyilkan
IntroductionThe prognostic value of HER2 expression in patients with advanced non-small cell lung cancer remains controversial. The relationship between HER2 expression, and platinum resistance and patient survival, was investigated.MethodsSeventy-three consecutive patients (median age, 61 years) with stage IIIB and IV non-small cell lung cancer, admitted between February 2004 and December 2006, were included in this study. Sixty-one patients received gemcitabine, given as two 1250 mg/m2 doses on days 1 and 8 and, cisplatin, given as a 75 mg/m2 dose on day 8. Twelve patients received vinorelbine, given as two 25 mg/m2 doses on day 1 and 8, and cisplatin, given as a 75 mg/m2 dose on day 1. Both treatment paradigms were repeated on a 21-day cycle. Tumor response was evaluated by comparing tumor size on computerized tomography scans before and after three cycles of chemotherapy. HER2 status was examined by immunohistochemical analysis of paraffin-embedded specimens.ResultsHER2 was positive in 21 of 73 patients (28.8%). Of the 21 patients with HER2 positivity, 13 (61.9%) responded to chemotherapy with either a complete response, partial remission, or evidence of stable disease. Of 52 HER2-negative patients, 48 (92.3%) exhibited a response to chemotherapy. The difference in response to therapy between HER2-positive and -negative patients was statistically significant (p = 0.003). The median overall survival duration for all patients was 13 months. Median overall survival time was 14 months for HER2-negative patients and 10 months for HER2-positive patients (log-rank p = 0.007).ConclusionNon-small cell lung cancer patients with high expression of HER2 exhibited resistance to cisplatin-based chemotherapies that are the standard treatment for this disease. Our results indicate that HER2 status may be a predictive and prognostic factor for cisplatin- based therapy response and disease survival.
Tumori | 2000
Nazan Günel; Zafer Akcali; Deniz Yamac; Erhan Onuk; Erdal Yilmaz; Orhan Bayram; Ercüment Tekin; Uğbur Coşkun
Aims and background Breast cancer refractory to known effective agents is one of the major clinical problems frequently encountered in practice. Cisplatin and vinorelbine are known to be active drugs in anthracycline-refractory cases. In this phase II study, the effectiveness and tolerability of cisplatin and vinorelbine was investigated when used in combination as a salvage regimen in the treatment of metastatic refractory breast cancer. Study design Twenty-four patients with advanced refractory breast cancer who had been previously treated with a regimen containing doxorubicin were included in the study. Six of the 24 patients also received taxanes after failure of doxorubicin. Cisplatin at 80 mg/m2 on day 1 and vinorelbine at 25 mg/m2 on days 1 and 8 were given every 3 weeks. Results A total of 98 cycles of chemotherapy was given, with a median of 4/patient. The response rate was 25% (2 [8.3%] complete and 4 [16.7%] partial responses). The median survival rates were 14 months in responders and 5.5 months in nonresponders (P = 0.0282). One complete and one partial response were observed in patients previously treated with paclitaxel (overall response rate, 33%). The median response duration was 12.5 mo (range, 4–21) in complete and 4.5 mo (range, 1.5–13) in the partial response group. Grade 3 and 4 neutropenia occurred in 9 patients, with no toxic deaths. Grade 2-3 nausea and vomiting in 6 patients and grade 1 neuropathy in 1 patient were noted. Conclusions Although the number of cases is insufficient to indicate that the combination will be effective, it is noteworthy in consideration of anthracycline and taxane refractory cases. A combination of cisplatin and vinorelbine seems to be a reasonable and acceptable choice as an alternative salvage regimen in such cases.
principles and practice of constraint programming | 2006
Yesim Yildirim; Ozgur Ozyilkan; Zafer Akcali; Basturk B
OBJECTIVE To report on possible adverse interaction between capecitabine and warfarin in a patient with cancer, who developed subconjunctival and nose bleeding during treatment with these drugs and review of the previously reported five cases in the literature. CASE SUMMARY In the second week of capecitabine treatment the patient was hospitalized owing to subconjunctival hemorrhage and nose bleeding. Her international normalized ratio (INR) level was found to have increased, and both drugs were discontinued. Fresh frozen plasma replacement was administered. Warfarin and capecitabine treatment were restarted again but the warfarin dose was decreased. The patients INR was kept between 2.5-3 with the reduced dose of warfarin. DISCUSSION Capecitabine is an orally active prodrug of fluorouracil (FU) and is extensively used as an antineoplastic agent. It is converted to 5-FU in the liver and tumor tissues. Warfarin is an antithrombolytic agent and is metabolized by liver cytochorom P450 (CYP) isoenzymes in liver. Preclinical in vitro studies using human liver microsomes report no inhibitory effects between capecitabine and substrates of CYP. However, the concomitant administration of capecitabine and warfarin resulted in gastrointestinal, retroperitoneal bleeding and hemorrhagic blisters in the five cases previously reported. The exact mechanism of this interaction is unknown; however, a significant pharmacokinetic interaction between capecitabine and S-warfarin resulting in exaggerated anticoagulant activity has recently been demonstrated. Here, we describe another case and use of the Naranjo adverse drug reaction (ADR) probability scale, which indicated a probable relationship between subconjunctival bleeding and epistaxis in this patient after concomitant warfarin and capecitabine use. CONCLUSION Capecitabine is extensively used in outpatient clinics, and physicians should be aware of ADRs arising from combined used of capecitabine and warfarin. In the light of the current data, INR levels should be closely monitored in patients using this medication regimen.
Tumori | 2008
Zafer Akcali; Zuleyha Calikusu; Hakan Sakalli; Ozgur Ozyilkan
Aims and Background Gemcitabine and cisplatin treatment were administered to patients with advanced-stage, non-small-cell lung cancer. During phase II studies, the treatment is performed using a 28-day cycle, with gemcitabine administered on days 1, 8, and 15. Although it is advised that cisplatin not be administered on the first day, gemcitabine and cisplatin treatment is usually performed using a 21-day cycle, with gemcitabine administered on days 1 and 8, and cisplatin is given on the first day in most phase III studies. In contrast with previous phase III studies, cisplatin was administered on day 8 in our study. Dose density, drug toxicity, and efficacy were analyzed. Methods and Study Design Chemonaive patients with stage IIIB or stage IV non-small-cell lung cancer received gemcitabine (1250 mg/m2) on days 1 and 8 plus cisplatin (75 mg/m2) on day 8 every 3 weeks (1 cycle contained 2 applications). Results Sixty-seven patients received a total of 293 applications. Dose densities were 92.3% for gemcitabine and 93.9% for cisplatin. The types and rates of grade 3 and grade 4 hematologic toxicities were anemia (6%), granulocytopenia (46%), and thrombocytopenia (6%). Complete remission was seen in 2 patients (3%); partial remission was 40%, stable disease was 39%, and progression of disease, 10%. The median overall survival time was 13 months. The median progression-free survival time was 9.5 months. One-year survival rate was 54% and 2-year survival, 10.4%. Conclusions In this 21-day treatment regimen, overall survival was longer than 1 year and the 1-year survival rate was more than 50%. Both the severity and rate of observed thrombocytopenia in the study were very low. Other adverse effects in the current study were comparable to those reported in the literature.
Tumori | 2001
Nazan Günel; Deniz Yamac; Zafer Akcali; Ferit Taneri; Mehmet Oguz
Background/aim Colorectal cancer is seen mostly among patients older than 50 years of age. An aggressive behavior is a frequently cited as characteristic of colorectal cancer in young patients. The purpose of the present study was to reveal the clinicopathologic characteristics of colorectal cancer among patients under 50 years of age. Methods Two hundred and seventy-one patients with colorectal cancer admitted to our oncology center were evaluated, and clinicopathologic findings of the young and old patients were compared. Patient gender, site distribution, tumor stage classification, lymph node involvement, metastatic site, histologic classification, histologic differentiation, family history of malignant tumors, presenting symptoms and survival rates were compared. Results One hundred patients were 50 years of age or under. Clinical, histopathologic characteristics and overall survival of the two groups did not differ. A higher rate of familial cancer syndromes was detected among young patients. Conclusions The presentation and outcome of the disease in young patients do not differ from those of older patients. A significant family history of colorectal cancer in the young patients showed the need for screening whereas the outcome of metastatic disease was poor. In order to anticipate long survival, early detection and aggressive treatment is necessary.
Tumori | 2005
Yesim Yildirim; Zafer Akcali; Banu Bilezikçi; Ozgur Ozyilkan
Squamous cell carcinoma (SCC) originating from the stomach is a relatively rare entity. There are theories regarding the development of this rare tumor, but its exact pathogenesis remains obscure. Fewer than 100 cases of primary SCC of the stomach have been presented in the literature. Due to the advanced stage at the time of diagnosis in most of these cases, the prognosis is generally poor. In the case presented here, dissemination of the tumor to the transverse colon, gallbladder and omentum was present at diagnosis. Despite the tumors advanced stage, complete remission was achieved after six courses of adjuvant chemotherapy with 5-flourouracil and cisplatin. No recurrence has been detected during follow-up. The patient has been healthy with no sign of the disease for three years.
Journal of Clinical Neuroscience | 2010
Yesim Yildirim; Zafer Akcali; Ozgur Ozyilkan
Primary signet-ring cell carcinoma of the colon is rare. Most patients with this type of cancer have a poor prognosis. We describe a patient with signet-ring cell carcinoma of the colon, for whom leptomeningeal metastasis presented a variety of clinical symptoms.
Indian Journal of Cancer | 2005
Dilsen Colak; Ozgur Ozyilkan; Zafer Akcali; Banu Bilezikçi
Chronic lymphocytic leukemia (CLL) is the most common type of leukemia worldwide. It is an indolent disease, almost exclusively of B-cell origin. Some CLLs evolve into a more aggressive lymphoid malignancy. The most common of these is Richters syndrome. Transformation to acute lymphoblastic leukemia, plasma cell leukemia, multiple myeloma, or Hodgkins disease (HD) may also occur. CLL patients are also at a significantly increased risk of developing a second malignant neoplasm later in life. One of the most common of these is HD. Herein, we report a case of HD in an elderly man with a history of B-cell CLL.
Onkologie | 2004
Sema Karakus; Ozgur Ozyilkan; Zafer Akcali; Beyhan Demirhan; Mehmet Haberal
Background: Leukemia is a well-known complication of cancer therapy, but development of acute myeloid leukemia (AML) after renal transplantation is rare. Immunosuppressive therapy for organ transplant recipients is complicated by high rates of malignant disease, one condition being Kaposi’s sarcoma (KS). Case report: A 22-year-old woman developed KS 1 year after renal transplantation, and then developed AML another 4 years later. When KS was diagnosed it was already in extensive stage, and she received ABV combination chemotherapy with doxorubicin plus bleomycin plus vincristine intravenously (i.v.) once daily every 2 weeks. She entered remission but the KS relapsed and 8 cycles of i.v. etoposide monotherapy were given and she re-entered remission. 19 months later, the patient was admitted to hospital with severe malaise, leukocytosis, thrombocytopenia, and anemia. The diagnosis was AML (FABM4). The patient received induction chemotherapy consisting of cytarabine and idarubicin. After completion of this induction therapy she developed neutropenic infection, dyspnea and confusion. Her condition deteriorated rapidly after that, and she died. Conclusion: KS is one of the most common malignancies in renal allograft recipients, whereas AML is a less frequent problem. To our knowledge, this is the first published case of these two different malignancies developing after renal transplantation. The pathogenesis of the AML is discussed.