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Dive into the research topics where Filiz Ozyilmaz is active.

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Featured researches published by Filiz Ozyilmaz.


Breast Journal | 2003

Evaluation of Tumor Angiogenesis with Contrast-Enhanced Dynamic Magnetic Resonance Mammography

Nermin Tuncbilek; Ercüment Ünlü; Hakki Muammer Karakas; Bilge Cakir; Filiz Ozyilmaz

Abstract:  The goal of this research was to correlate dynamic magnetic resonance (MR) mammographic contrast enhancement and microvessel densities in breast masses. Forty‐six female patients with breast masses detected by mammography and/or ultrasonography were included in the study. MR contrast enhancements of the lesions were investigated dynamically using axial three‐dimensional fast low‐angle shot sequences. After excisional biopsy or mastectomy, immunohistochemical staining with factor VIII‐RA was performed, followed by microvessel density measurements. Contrast enhancement patterns in dynamic MR mammography were compared with microvessel density measurements using Students t‐test, Pearsons moment correlation coefficients, and one‐way analysis of variance (ANOVA). Malignant lesions exhibited three different enhancement patterns: 1) a peak enhancement within 120 seconds (early phase), followed by a decrease in the delayed phase (25 cases); 2) an increase in the early phase, followed by a plateau in the delayed phase (9 cases); and 3) an increase throughout the examination without any peak (5 cases). In benign lesions, signal intensity did not exhibited a peak in five cases, whereas in two cases enhancement was increased in the early phase and made a plateau in the delayed phase. A significant correlation was found between microvessel density and the percentage of maximal signal increase following paramagnetic contrast administration (r = 0.322, p < 0.05). Dynamic enhancement patterns and rates of maximal signal increase predict microvessel density in breast malignancies and may possibly be used as prognostic indicators.


Clinical Imaging | 2001

Primary angiosarcoma of the spleen: In vivo and in vitro MRI findings

Hakki Muammer Karakas; Muzaffer Demir; Filiz Ozyilmaz; Bilge Cakir

Primary splenic angiosarcomas are extremely rare tumors with very poor prognosis. These tumors, highly aggressive and lethal, present with widespread metastatic disease or splenic ruptures. The possibility to lengthen the survival by splenectomy before the development of splenic rupture makes an early radiological diagnosis a necessity. Multimodality imaging findings of a patient with splenic angiosarcoma is presented. In vivo and in vitro magnetic resonance imaging (MRI) features of the spleen are compared to macro- and micropathological findings.


Neurosurgery | 1994

Spinal tuberculosis with circumferential involvement of two noncontiguous isolated vertebral levels: case report.

Alpaslan Kulali; Sabahattin Çobanoğlu; Filiz Ozyilmaz

We present a case of a 16-year-old boy with an atypical form of spinal tuberculosis, which circumferentially involved two noncontiguous vertebral levels without destruction of the adjacent vertebral bodies and intervertebral discs. The lesions caused paraplegia and loss of sphincter control, and they were confined to a single vertebra at each site; the findings more closely mimicked spinal malignancies. There was no evidence of pulmonary or other extrapulmonary tuberculous disease. The patient was successfully treated both surgically and medically using posterior decompression and a stabilizing procedure in combination with postoperative antituberculous therapy. Magnetic resonance imaging played a major role in determining the extent of the disease and the type of surgical procedure and in monitoring adequate medical treatment.


Urology | 2009

Massive Upper Gastrointestinal Bleeding From Pure Metastatic Choriocarcinoma in Patient With Mixed Germ Cell Tumor With Subclinical Intestinal Metastasis

Irfan Cicin; Filiz Ozyilmaz; Hakan Karagol; Fatma Yalcin; Sernaz Uzunoglu; Mustafa Kaplan

Although testicular germ cell tumors have become curable neoplasms, a better understanding of the clinicopathologic features is needed for the rare manifestations associated with treatment failure. We report a rare case of metastatic pure choriocarcinoma involving the small intestine arising from a testicular mixed germ cell tumor. In a patient who developed massive upper gastrointestinal hemorrhage during treatment, the intestinal metastases and focus of bleeding could only be determined by laparotomy. We propose an approach for the determination of subclinical intestinal metastases of testicular germ cell tumor; the case is discussed in light of similar reports in literature.


Surgical Neurology | 1994

Giant calcified subdural empyemas

Alpaslan Kulali; Cihanser Erel; Filiz Ozyilmaz; Osman Simsek

We report two cases of chronic calcified and ossified subdural empyema diagnosed during surgery and operated on successfully using an extraordinary large osteoplastic craniotomy. After surveying the literature, we must emphasize the unusual occurrence of the chronic subdural empyemas presenting with calcification-ossification and large size as observed in both of our cases.


Balkan Medical Journal | 2015

Histopathological Features of Gastrointestinal Stromal Tumors and the Contribution of DOG1 Expression to the Diagnosis

Beril Guler; Filiz Ozyilmaz; Burcu Tokuç; Nuray Can; Ebru Tastekin

BACKGROUND Gastrointestinal stromal tumors (GIST) have KIT or platelet-derived growth factor receptor α (PDGFRα) mutations affecting receptor tyrosine kinase activity and do not benefit from classic treatment regimens. AIMS The aim of this study was to review the algorithm that may be followed for the diagnosis and differential diagnosis in GISTs by investigating the histomorphological parameters and expression characteristics of classical immunohistochemical antibodies used in routine tests in addition to DOG1 expression. STUDY DESIGN Diagnostic accuracy study. METHODS We reevaluated the histological and immunohistochemical parameters of 37 GISTs. The standard immunohistochemical diagnosis and differential diagnosis panel antibodies (CD117, PDGFRα, CD34, vimentin, desmin, SMA, S-100, and Ki67) were studied on the tumor sections. We also used the popular marker DOG1 antibody with accepted sensitivity for GISTs in recent years and the PDGFRα immune marker for which the benefit in routine practice is discussed. RESULTS Classification according to progressive disease risk groups of the 37 cases revealed that 54% were in the high risk, 19% in the moderate risk, 16% in the low risk, 8% in the very low risk and 8% in the no risk group. Cytological atypia, necrosis, mucosal invasion and the Ki67 index were found to be related to the progressive disease risk groups of the tumors (p<0.05). Positive immunoreaction was observed with CD117 and PDGFRα in all GISTs in the study (100%). Positivity with the DOG1 antibody was found in 33 (89%) cases. CD34 was positive in 62% (23) of the cases. CONCLUSION The CD117 antibody still plays a key role in GIST diagnosis. However, the use of DOG1 and PDGFRα antibodies combined with CD117 as sensitive markers can be beneficial.


Turkish Journal of Pathology | 2017

Tert expression in pituitary adenomas

Nuray Can; Mehmet Celik; Buket Yilmaz Bulbul; Necdet Sut; Filiz Ozyilmaz; Semra Ayturk; Sibel Guldiken; Nurtac Sarikas; Fulya Oz Puyan; Tulin Yalta; Ali Kemal Kutlu

OBJECTIVE Although pituitary adenomas have benign histomorphological features, some of them may present in an aggressive manner. To predict the behaviour of these tumours, telomerase reverse transcriptase (TERT) activity in pituitary adenomas has been the subject of a few studies with contradictory results. This study aims to investigate whether immunohistochemical expression of TERT differs in neoplastic and nonneoplastic pituitary tissues and aims to investigate whether TERT expression is related to clinicopathological features of pituitary adenomas. MATERIAL AND METHOD The study included 48 patients who had been diagnosed with pituitary adenomas and had clinical follow-ups. Nonneoplastic pituitary tissues were obtained from autopsy specimens (n=20). Immunohistochemistry for TERT antibody was performed. Both the nuclear and cytoplasmic expression of TERT antibody was noted, and total combined TERT staining was evaluated according to nuclear and cytoplasmic stainings. RESULTS TERT expression did not differ between neoplastic and nonneoplastic pituitary tissues. Neither total (combined nuclear and cytoplasmic) TERT nor nuclear TERT expression revealed any statistically significant relationship with any of the clinicopathological features. Higher cytoplasmic TERT expression was observed in adenomas with recurrence than adenomas without recurrence (p=0.035). CONCLUSION This study introduces the notion that immunohistochemical expression of TERT does not differ in neoplastic and nonneoplastic pituitary tissues. Pituitary adenomas with cytoplasmic immunohistochemical expression of TERT have significantly higher rates of recurrence. Further studies, including combined methods of immunohistochemistry and molecular analyses in larger groups, may reveal applicable results for the clinical significance of TERT in pituitary adenomas.


Turkish Journal of Pathology | 2014

Congenital Pulmonary Airway Malformation Type 2: A Case Report with Review of the Literature

Ebru Tastekin; Ufuk Usta; Aysegul Kaynar; Cigdem Ozdemir; Omer Yalcin; Filiz Ozyilmaz; Ali Kemal Kutlu

Abstract A congenital pulmonary airway malformation is a rare disorder of the pulmonary airway and a hamartomatous mass of disorganized lung tissues with various degrees of cystic change. A 20-year-old pregnant woman who did not have previous clinical follow-up during her pregnancy visited the gynecology department for her first check on the 19th week of gestation. The sonogram, showed severe hydrops fetalis. Laboratory findings were consistent with non-immune hydrops fetalis. Medical abortion was performed and the fetus was sent to our department for a complete fetal autopsy. Macroscopically, whole parts of the fetus had striking oedema. Massive pleural and peritoneal effusions were seen on dissection. The left lung filled the whole thoracic cavity. The heart was displaced to the right and the right lung was compressed. Microscopically, the left lung mass showed dilated bronchiole-like structures (1-20 mm) that were lined with ciliated columnar cells without any intervening mucinous cells. The subepithelial stroma contained thin, interrupted smooth muscle fibers and elastic connective tissue without cartilage plates. Our case is a very good example of non-immune hydrops fetalis associated with congenital pulmonary airway malformation type 2. Prenatal clinical and ultrasonographic follow-ups during pregnancy are very important for early diagnosis of congenital malformations.


Polish Journal of Pathology | 2016

Histological perspective on the effects of tumor-associated macrophages in the tumor microenvironment surrounding papillary thyroid carcinoma

Nuray Can; Semra Ayturk; Mehmet Celik; Yavuz Atakan Sezer; Filiz Ozyilmaz; Ebru Tastekin; Necdet Sut; Funda Ustun; Buket Yilmaz Bulbul; Fulya Oz Puyan; Sibel Guldiken

Tumor-associated macrophages (TAMs) are one of the most noticeable elements of the tumor microenvironment. The present study investigated the relationships between the density of CD163 immunolabeled M2-like TAMs with other histological properties of the tumor microenvironment and clinipathological features in 90 patients with papillary thyroid carcinomas (PTC). The percentage of TAMs was higher in tumors with significant lymphocytic tumor response (p = 0.020), in tumors with a significant degree of stromal tumor response (p = 0.014), those with infiltrative tumor borders (p = 0.029), in conventional variant papillary carcinoma (p = 0.032), and in patients with autoantibodies for thyroid peroxidase (p = 0.014). The tumors associated with lymphocytic thyroiditis had lower numbers of TAMs (p = 0.027). In conclusion, for the first time, the present study attempts to establish a full assessment of interactions of CD163 expressing M2-like TAMs with the triad of primary tumor- tumor microenvironment- tumor behavior and above all, with markers of autoimmunity. Thus, these alternatively polarized macrophages may act in tumor progression and dissemination according to their various products, which may be ordered by tumor cells or neighboring immune cells. The molecular studies may reveal their roles in various tumors and may improve the therapy strategies targeting TAMs in various malignant tumors, including PTCs.


Polish Journal of Pathology | 2017

Comparison of clinicopathological features in incidental and nonincidental papillary thyroid carcinomas in 308 patients

Nuray Can; Filiz Ozyilmaz; Mehmet Celik; Atakan Sezer; Necdet Sut; Ebru Tastekin; Semra Ayturk; Funda Ustun; Buket Yilmaz Bulbul; Sibel Guldiken

Incidental papillary thyroid carcinomas (IPTCs) consist of a significant portion of increasing incidence in papillary thyroid carcinomas. This study investigated the clinicopathological features of IPTCs from different perspectives and by comparing nonincidental PTCs (NIPTCs) in patients who underwent total thyroidectomy and lymph node dissection. Basic results were as follows. IPTC was present in 27.9% of 308 patients. IPTCs were significantly accompanied by lymphocytic thyroiditis (LT), particularly, multinodular hyperplasia (MNH). IPTCs were more common in older patients (51.3 years vs. 47.2 years) and in female patients. IPTCs significantly differed from NIPTCs in terms of smaller tumour size, lymphatic vessel invasion (2.6% vs. 97.4%), extrathyroidal extension (4.3% vs. 95.7%), lymph node metastasis (3.6% vs. 96.4%), multifocality (21.2% vs. 78.8%), bilaterality (5.3% vs. 94.7%), and BRAFV600 mutation (6.7% vs. 93.3%). Older age, bilaterality, encapsulation, and radioactive iodine (RAI) were significantly more common in IPTCs > 5 mm than in those ≤ 5 mm. In conclusion, IPTCs are more commonly associated with LT and MNH. IPTCs may have a more favourable prognosis than NIPTCs, and tumour size > 5 mm may predict bilaterality and need for RAI. Nevertheless, the patient-based clinical approach in IPTCs may have benefits in the management of IPTCs.

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