Ahmet Sezer | Baskent University (original) (raw)

Papers by Ahmet Sezer

Medical science monitor : international medical journal of experimental and clinical research, Jan 20, 2014

Malignant pleural mesothelioma is a rare lethal malignancy caused by asbestos exposure. It is mor... more Malignant pleural mesothelioma is a rare lethal malignancy caused by asbestos exposure. It is more frequently seen in certain regions in Turkey. In this retrospective study, we aimed to analyse demographic, clinical, and pathological data and treatment-related features in 54 patients. The study included 54 patients diagnosed with malignant mesothelioma that were followed and treated. Of the 54 patients, 34 (55.6%) were male. The median age in men and women were 60.3 (38.2-77.2) and 65.8 (37.7-77.5) years, respectively. In 35 (64.8%), exposure to asbestosis was present. Epithelial type was found in 27 (50.0%), followed by mixed type in 7 (13.0%) patients, and in 20 (37.0%) patients the subtype could not be determined. The disease was staged as IV in 37 (68.5%) patients. In 28 patients (51.9%), it was right-sided and in 1 (1.9%) it was bilateral. The most frequent metastatic sites (in decreasing order) were lungs, mediastinum, diaphragm, liver, and thoracal wall. Of the 54 patients, 3...

Asian Pacific journal of cancer prevention : APJCP, 2011

The majority of patients with head and neck cancer are treated with concurrent chemoradiotherapy.... more The majority of patients with head and neck cancer are treated with concurrent chemoradiotherapy. However, toxicity is substantial so that alternate schedules of cisplatin have been tried to overcome this problem. No formal comparison, however, has been reported between alternate schedules and reference regimen. Fifty-five eligible patients treated with concurrent chemoradiotherapy were retrospectively analyzed. The patients treated with weekly cisplatin were defined as group A, while the patients treated with standard regimen were defined as group B. Basic demographics and clinical characteristics', overall survival rate, locoregional or systemic relapse rates, and time to local/systemic relapse were recorded. One, two, and three-year probability of survival in groups A and B were 75% to 65% after one year, 63% to 56%after two, and 63% to 52% after three, respectively. Although time to local and systemic relapse was higher in group B as compared to group A, a statistical analys...

Turkish Journal of Trauma and Emergency Surgery, 2012

In this study, we aimed to set levels of blood S100B and lactate and to determine any correlation... more In this study, we aimed to set levels of blood S100B and lactate and to determine any correlation with brain computerized tomography in minor head traumas in children and adults. This clinical trial is a prospective study including 100 head trauma patients who applied to Ankara Training and Research Hospital emergency service. In this study, cut-off ranges of 0.0-0.15 ug/ml and 0.9-1.7 mmol/L for blood S100B and lactate levels, respectively, were used. S100B level was higher than the cut-off range in 42% of patients and lactate level was higher in 56% of patients. No significant differences were determined between age groups. When the relation between S100B and lactate levels with brain CT was evaluated, no statistically significant relation was determined. According to our results, in minor head traumas, the determination of elevated serum S100B and lactate levels cannot take the place of clinical examination and the use of cranial CT. Although the patients in our study group had minor head trauma, we do not consider S100B and lactate to be reliable markers for estimating progression.

Medical Oncology, 2014

Accompanying comorbidities observed during the cancer treatment usually affect the course and out... more Accompanying comorbidities observed during the cancer treatment usually affect the course and outcome of the therapy. Hypovitaminosis D, which is one of these conditions, is a resolvable problem, if recognized. In this study, we investigated whether the serum 25(OH)D levels of the patients who were presented to our outpatient clinic were different from the serum levels of the healthy population living in the same area. Our study included 90 patients who were presented to the Medical Oncology outpatient clinic and 90 age, gender, body mass index and ethnic origin matched controls without a known disease, who were presented to the outpatient clinics of the Departments of Internal Diseases and Family Medicine for routine controls. Blood count tests, detailed biochemistry tests (including serum levels of Cr, Ca and P), measurement of serum 25(OH)D levels and C-reactive protein were performed in serum samples of all of the patients and controls. Mean serum levels of 25(OH)D were 13.5 ng/ml (SD 5.1) in all cancer patients, 13.1 ng/ml (SD 4.2) in the patients who were presented for adjuvant therapy, 13.8 ng/ml (SD 5.5) in the patients who were presented at metastatic stage and 18.4 ng/ml (SD 12.5) in the controls. Mean serum CRP levels were 5.4 mg/dl (SD 1.2) in the control group, 8.4 mg/dl (SD 4.3) in the adjuvant therapy group and 20.3 (SD 16.8) in the patients with metastatic disease. Generally, all cancer patients (p 0.003) and the patients with metastatic cancer (p 0.004) had lower serum 25(OH)D levels compared to controls, and there was an inverse correlation between serum 25(OH)D and CRP levels in patients with metastatic cancer (p 0.036). In metastatic cancer patients, hypovitaminosis D may be a comorbidity and it is recommended to consider during initial evaluation and follow-up. Because it might improve these patients quality of life and chemotherapy adherence.

Onkologie, 2009

Although secondary renal involvement from systemic lymphoma is very frequent, primary renal lymph... more Although secondary renal involvement from systemic lymphoma is very frequent, primary renal lymphoma is a rare entity. It is characterized by aggressive histopathology, very early extra-renal infiltration and poor prognosis. Here, we report 4 cases of primary renal lymphoma presenting with unilateral renal masses, which after radiological and clinical examination were assumed to be renal cell carcinoma. 3 patients were diagnosed with Non-Hodgkin&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s lymphoma by nephrectomy and one patient was diagnosed by open renal biopsy. Histopathological subtypes were diffuse large B cell lymphoma in 2 cases and non-Hodgkin&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s lymphoma of small B cell type in the others. While 3 of the patients were treated with systemic chemotherapy, the fourth patient refused chemotherapy. 2 patients (no. 2 and 3) were still in complete remission and were followed regularly in the second and first year after diagnosis, respectively. Since it is difficult to diagnose primary renal lymphoma, most patients with this kind of tumor undergo radical nephrectomy, and diagnosis of primary renal lymphoma is delayed. The authors believe that both the delayed diagnosis due to anatomical difficulties and the histological aggressive characteristics of this disease are equally responsible for the poor outcome in the case of primary renal lymphoma.

Medical Science Monitor, 2014

Standard treatment of colorectal cancer includes both cytostatic chemotherapy and targeted therap... more Standard treatment of colorectal cancer includes both cytostatic chemotherapy and targeted therapies. Bevacizumab, targeting the VEGF receptor, is one of the primary targeted therapies that achieve better response rate and survival rate as compared to combination chemotherapy. To the best of our knowledge, there is no established single marker that can be used as a predictive marker in bevacizumab therapy. We enrolled 24 patients with the diagnosis of metastatic colorectal cancer in our study. During the study, 2 blood samples were drawn from patients before the first cycle and after the sixth cycle of bevacizumab therapy. Serum levels of VEGF, ANG II, and NO were recorded. While the change across VEGF levels was found to be a statistically significant decreasing trend (p=0.009), this decrease was not found to be correlated with treatment response and hypertension development. Additionally, no statistically significant difference was found in terms of NO and ANG II levels. This study showed a significant decrease in serum VEGF, but failed to show a significant change in NO and ANG II levels during bevacizumab treatment. Although no significant correlation was found between the presence of hypertension and markers, most patients (83%) had an increase in their blood pressure. Our results suggest that dynamic monitoring of NO and ANG II, along with VEGF, may not be useful as predictive markers for bevacizumab treatment in colorectal cancer.

Lung cancer (Amsterdam, Netherlands), 2011

Advanced thymic carcinoma (TC) is a very aggressive disease. To date there are no established tre... more Advanced thymic carcinoma (TC) is a very aggressive disease. To date there are no established treatment options for the refractory and recurrent disease and only a few prospective trials have been conducted in patients with TC. Here we present a case of a relapsed TC patient, who, by using combination chemotherapy, showed a positive response to sorafenib with C-KIT exon 11 mutation.

European Journal of Radiology, 2012

Purpose: Patients with advanced cholangiocarcinoma present with high rate of local complications.... more Purpose: Patients with advanced cholangiocarcinoma present with high rate of local complications. The primary aim of this study is to report clinical course of advanced cholangiocarcinoma patients those who were presented with biliary obstruction and treated with percutaneous biliary stenting. Material and methods: Patients with unresectable locally advanced or metastatic cholangiocarcinoma followed by our center for a period of 4 years were analyzed. For statistical analysis demographic and clinical characteristics of patients, primary biliary drainage method, metal stent occlusion rate, time to stent occlusion, and overall survival rates were recorded. Results: A total of 34 eligible patients were analyzed. 27 patients had metal stent placement. These 27 patients formed the basis of this study. Median overall survival (OS) was 6.0 months. After metal stent deployment bilurubin levels were normalized within a mean of 10 days. During the follow-up period, 13 patients were experienced metal stent occlusion. Median TtSO was 10 weeks. Cytotoxic chemotherapy was administered to 14 (52%) patients. Patients without stent dysfunction had significantly higher rate of chemotherapy exposure rate (p = 0.021). Statistical analysis, however, failed to exhibit significant effect of stent dysfunction on OS. Conclusion: In advanced cholangiocarcinoma, relief of bile duct obstruction is an important part of the initial patient management. This study therefore described the clinical value of percutaneous metal stent in cholangiocarcinoma patients and raises the question about patency of metal stent in cholangiocarcinoma whether we can expect success similar to the success achieved in pancreas carcinoma.

The aim of this study is to determine statistics knowledge of physicians and students according t... more The aim of this study is to determine statistics knowledge of physicians and students according to their major branches and statutes and find out their thoughts on the importance they give to the biostatistics education and finally decide at which semester the biostatistics education should be given.

Journal of B.U.ON. : official journal of the Balkan Union of Oncology

To study the data on the distress scale points (DSP) of patients in oncology clinics in relation ... more To study the data on the distress scale points (DSP) of patients in oncology clinics in relation to age, the reasons for admission to the hospital, the educational status and the family support. Six hundred and fifty three patients diagnosed with malignancies were enrolled. All of the patients were asked to fill in a questionnaire that included data about their demographic characteristics, diagnoses, the cause of hospital admission and the educational status. The family support of each patient was observed and noted by clinicians and other healthcare providers during the clinical visits. The mean patient age was 54.8 years (± SD 13.7). Of the patients 314 (48.1%) were male and 339 (51.9%) female. The median DSP for the group that included patients <35 years of age was 3; this was 5 for the 36-49 age group, 4 for the 50-69 age group and 4.5 for the >70 age group. A statistically significant difference in DSP between these groups was noticed (p=0.035). The DSP for patients <3...

Asian Pacific journal of cancer prevention : APJCP, 2014

Medical science monitor : international medical journal of experimental and clinical research, 2015

Background Concurrent chemoradiotherapy is the current standard treatment for inoperable stage II... more Background Concurrent chemoradiotherapy is the current standard treatment for inoperable stage III non-small cell lung cancer (NSCLC). In this study we aimed to investigate the efficacy and toxicity of CCRT with split dose of cisplatin (30 mg/m2) and vinorelbine (20 mg/m2) in patients with inoperable stage III NSCLC followed in our oncology clinic. Material and Methods Medical records of 97 patients with inoperable stage III NSCLC treated with concurrent chemoradiotherapy with cisplatin-vinorelbine were retrospectively analyzed. Cisplatin (30 mg/m2) and vinorelbine (20 mg/m2) were administered on days 1, 8, 22, and 29 during radiotherapy. Two cycles of consolidation chemotherapy were given. All patient data, including pathological, clinical, radiological, biochemical, and hematological data, were assessed retrospectively using our database system. Results Our study included 97 unresectable stage III NSCLC patients who were treated with CCRT. Median age was 58 years old (range 39-75)...

Molecular and Clinical Oncology, 2014

Soft tissue sarcomas (STS) are a group of rare mesenchymal cancers that include approximately 50 ... more Soft tissue sarcomas (STS) are a group of rare mesenchymal cancers that include approximately 50 histological types and account for 1% of all adult cancers. The standard curative treatment option for localized disease is surgical resection and, if a surgically removed tumor exhibits high-risk characteristics, adjuvant chemotherapy and radiotherapy may be administered. Sarcoma presenting at an advanced stage has a dismal prognosis and survival has not markedly improved over the last 20 years. The standard first-line treatment for advanced STS, other than gastrointestinal stromal tumors, is cytotoxic chemotherapy. Therapies targeting pro-angiogenic factors have been a focus of drug development for STS over the last few years. Pazopanib, a multitargeted tyrosine kinase inhibitor, is a novel treatment option for patients with metastatic STS in the second-line setting. This is a presentation of 2 case reports of patients with metastatic STS who responded well to treatment with pazopanib.

Leukemia & Lymphoma, 2009

Medical Oncology, 2015

Gastric cancer, with one million new cases observed annually, and its dismal prognosis, is one of... more Gastric cancer, with one million new cases observed annually, and its dismal prognosis, is one of the leading causes of cancer-related mortalities. Systemic chemotherapy is the main treatment modality in advanced gastric cancer patients. We aim to evaluate the predictive role of tumor localization and histopathology on choosing three or two-drug combination regimens. Consecutive 110 metastatic gastric adenocarcinoma patients who were admitted to the Baskent University Department of Medical Oncology and the Van Research and Training Hospital were included in the study. Data of patients were analyzed retrospectively. Median age of patients was 58 years (range 30-80). Proximal intestinal, distal intestinal, and diffuse gastric cancers were found in 35 (32 %), 64 (58 %), and 11 (10 %) patients, respectively. 5-fluoracil and platinum (PF) and PFtax were administered to 47 (43 %) and 63 (57 %) patients, respectively. Median progression-free survival (PFS) was 4.0 (95 % CI 2.5-5.6) and 7.4 months (95 % CI 6.0-8.7) for PF and PFtax groups, (p = 0.034). When we used tumor localization as strata in the PFS survival curve, PFtax produced significantly higher PFS rates only in distal intestinal-type gastric cancer, compared with PF (p = 0.03). Median overall survival (OS) was 9.0 (95 % CI 5.2-12.3) and 17.3 months (95 % CI 7.8-27) for PF and PFtax groups, (p = 0.010). When we used tumor localization as strata in the OS survival curve, PFtax produced significantly higher OS rates only in distal intestinal-type gastric cancer compared with PF (p = 0.015). Pathology and tumor location in gastric cancers may affect the outcome, the addition of taxanes as a third drug may significantly increase PFS and OS rate purely in distal intestinal-type gastric cancer but not in patients with proximal and diffuse-type gastric cancers.

Medical Oncology, 2012

Objective: To examine the prevalence of thyroid disease and dysfunction including thyroid autoimm... more Objective: To examine the prevalence of thyroid disease and dysfunction including thyroid autoimmunity in Norway. Materials and methods: All inhabitants 20 years and older (94 009) in Nord-Trùndelag were invited to participate in a health survey with a questionnaire and blood samples. Results: The prevalence of former diagnosed hyperthyroidism was 2.5% in females and 0.6% in males, hypothyroidism 4.8% and 0.9%, and goitre 2.9% and 0.4% respectively. In both sexes the prevalence increased with age. In individuals without a history of thyroid disease the median, 2.5 and 97.5 percentiles for TSH (mU/l) were 1.80 and 0.49±5.70 for females and 1.50 and 0.56±4.60 for males. The TSH values increased with age. When excluding individuals with positive thyroid peroxidase antibodies (TPOAb) (> 200 U/ml), the 97.5 percentiles dropped to 3.60 mU/l and 3.40 mU/l respectively. The prevalence of pathological TSH values in females and males were TSH $10 mU/l 0.90% and 0.37%; TSH 4.1±9.9 mU/l 5.1% and 3.7%; and TSH # 0.05 mU/l 0.45% and 0.20% respectively. The prevalence of positive TPOAb (> 200U/ml) was 13.9% in females and 2.8% in males. In females the lowest percentage (7.9%) of positive TPOAb was seen with TSH 0.2± 1.9 mU/l and increased both with lower and higher levels of TSH. The percentage of males with positive TPOAb was lower than in females in all TSH groups except for those with TSH > 10 mU/l (85% TPOAb positive). Conclusions: In spite of a high prevalence of recognised thyroid disease in the population a considerable number of inhabitants have undiagnosed thyroid dysfunction and also positive TPOAb.

Współczesna Onkologia, 2014

Supportive Care in Cancer, 2013

Background Patients with advanced cancer may present with obstructive jaundice. Biliary stenting ... more Background Patients with advanced cancer may present with obstructive jaundice. Biliary stenting is the treatment of choice. However, which patients benefit most is not well-defined, yet. Our aim was to delineate the clinical factors affecting prognosis. Material and methods Charts of 140 patients with advanced cancer who underwent biliary stenting were retrospectively analyzed. Their median age was 63.5 years. Of these patients, 73 (52.1 %) were male, 32 (22.9 %) had ECOG PS 1 and 81 (57.9 %) had PS 2. The most frequent cancer types were cholangiocellular cancer (64, 45.7 %) and pancreatic cancer (36, 25.7 %). Results Median overall survival (OS) was 141 (95 % CI, 100.7-185.3) days. Female patients lived longer (161.0 vs. 124.0 days) (p00.036). Those patients with colorectal cancer lived the longest (667.0 days), followed by cholangiocellular (211.0 days), and gastric cancers (106.0 days) (p00.004). The distribution of primary diagnosis differed significantly between sexes: cholangiocellular cancer was present in 22 (30.1 %) out of 73 men and 42(62.7 %) out of 67 women (chi-square p<0.001). There was a trend for longer overall survival if ALT (p00.08) and AST (p0 0.06) were normalized after stent insertion. Of the 137 patients, 63 (45.5 %) did not experience any complication. In 74 patients with complications, there were 39 (28.5 %) episodes of cholangitic infections and 35 (25.5 %) biliary obstructions. In three patients, we could not find data on infections. Conclusion Underlying malignancy, hence the natural biology and the therapeutic expectations are probably the most important factors which must be considered during decision-making.

Annals of Emergency Medicine, 2008

No abstract is available. To read the body of this article, please view the Full Text online. ...... more No abstract is available. To read the body of this article, please view the Full Text online. ... © 2008 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved. ... Visit SciVerse ScienceDirect to see if you have access via your institution.