Onak Kandemir N. | Dogan Gün B. | Irkörücü O. | Tokgöz H. | Barut F. | Cömert M. | Özdamar Ş.O.

Letter | 2011 | Turkish Journal of Gastroenterology22 ( 2 ) , pp.235 - 236

[No abstract available]

Onak Kandemir N. | Bahadir B. | Bektaş S. | Barut F. | Yurdakan G. | Dogan Gün B. | Engin H.

Article | 2011 | Turkish Journal of Gastroenterology22 ( 1 ) , pp.77 - 82

Congenital melanocytic nevi are hamartomatous lesions that develop from the neural crest and arise during odontogenesis. In this report, we present two malignant melanoma cases developed from congenital melanocytic nevi and revealed by gastrointestinal system metastases. The first case was a 71-year-old female who presented with pleural and peritoneal effusion and underwent biopsy due to detection of nodular lesions in the duodenum by endoscopic examination. The second case was a 36-year-old male patient who presented with abdominal pain in whom segmental ileal resection was performed due to mass lesions causing invaginations in the . . . ileum. Histopathological examination of the lesions showed a diffuse neoplastic infiltration comprising the entire mucosal layers. In neoplastic cells having a marked atypia and pleomorphism, immunoreactions with S-100, HMB-45, and Melan A were detected. Both cases were diagnosed as malignant melanoma. Abdominal skin in the first case and the femoral region in the second case exhibited congenital melanocytic nevi, and those lesions were determined to show a transformation towards malignant melanoma in the histopathological studies. Malignant melanoma development in gastrointestinal system may have a primary or metastatic character. Definitive diagnosis always requires detailed clinical, histopathological and immunohistochemical analyses Daha fazlası Daha az

Onak Kandemir N. | Barut F. | Keser S. | Karadayi N. | Bektaş S. | Dogan Gün B. | Bahadir B.

Article | 2009 | Turk Onkoloji Dergisi24 ( 4 ) , pp.172 - 176

OBJECTIVES This study examined the frequency of chronic lymphocytic thyroiditis (CLT) in thyroid papillary carcinomas (TPC) and the relationship between the presence of tumor-infiltrating lymphocytes (TIL) and CLT. METHODS The study included 61 TPC cases. In each case, the presence of the lymphocyte infiltration in the tumor tissue and non-neoplastic parenchyma was graded semi-quantitatively using a scale of 0 to 3. The cases were classified in two groups, TPC including CLT (Group I) and TPC not including CLT (Group II). RESULTS CLT was detected in 26.3% (Group I) of the TPCs and TIL was observed in 77% of the Group I cases; no lymp . . .hoid infiltration compatible with TIL was detected in Group II. A significant difference was observed in the TIL density between Groups I and II. CONCLUSION CLT is a frequent finding in TPC, and the presence of TIL is related to CLT. © 2009 Association of Oncology Daha fazlası Daha az

Onak Kandemir N. | Bektaş S. | Barut F. | Bahadir B. | Yurdakan G. | Dogan Gun B. | Mungan A.

Article | 2010 | Turk Onkoloji Dergisi25 ( 2 ) , pp.49 - 56

OBJECTIVES: The contribution of cytological methods to the diagnosis and follow-up of urinary system malignancies was investigated in this study, along with histological diagnosis and clinical follow-up results of the cases. METHODS: One hundred forty-four cases who underwent cystoscopy in ZKÜTF Urology Department between 2003 and 2007 were included in this study, and urinary cytology and biopsy samples were assessed in the Pathology Department. RESULTS: When cytological and histological diagnoses were compared, results in 17 positive cases and in 109 negative cases were consistent. Three cases were false-positive and 15 cases were . . .false-negative. In our series, sensitivity of urinary cytological diagnostic methods was 53% and specificity was 97%. CONCLUSION: Our study shows that urinary cytology has a high diagnostic value in the evaluation of urinary system diseases. However, decrease in the sensitivity of this method in low-grade urothelial tumors should be taken into account. © 2010 Association of Oncology Daha fazlası Daha az

Barut F. | Onak Kandemir N. | Karakaya K. | Kökten N. | Özdamar Ş.O.

Article | 2011 | Turkish Journal of Gastroenterology22 ( 3 ) , pp.324 - 328

Multifocal and skip involvement is quite a rare developmental pattern for primary gastrointestinal lymphomas. A 25-year-old male patient with diffuse large B-cell lymphoma of the small intestine, with macroscopic features and clinical aspects imitating Crohn's disease and attracting attention with cobblestone-like appearance, is presented herein together with the clinical and pathological features. Multiple ulcerated lesions were also observed infiltrating the serosa with polypoid appearance, 2.5 cm in largest diameter, within the resected jejunoileal specimen, which displayed patchy, healthy-appearing mucosal areas. In microscopic . . .examination, a tumoral infiltration was observed comprised of pleomorphic, atypical lymphoid cells with abundant eosinophilic cytoplasm, marked nucleoli and vesicular nuclei. A B-cell phenotype immunoreaction was observed by vimentin, LCA, CD20, and CD79a in those atypical cells. The diagnosis of the case was diffuse large B-cell lymphoma.The possibility of the presence of this disorder, although rare, is emphasized here for patients applying to the hospital with the signs and symptoms of Crohn's disease Daha fazlası Daha az

Barut F. | Onak Kandemir N. | Ozdamar S.O. | Gul S. | Bektas S. | Dogan Gun B. | Bahadir B.

Article | 2009 | Turkish Neurosurgery19 ( 4 ) , pp.417 - 422

Barut F. | Bektaş S. | Bahadir B. | Onak Kandemir N. | Karadayi N. | Özdamar Ş.O.

Article | 2009 | Turkiye Klinikleri Journal of Medical Sciences29 ( 1 ) , pp.42 - 47

Objective: The gold standard for diagnosis of papillary thyroid carcinoma is conventional histology, which depends on the characteristic nuclear features, regardless of whether papillary architecture is present or not. This study was carried on to evaluate the utility of cytokeratin-19 in the diagnosis and differential diagnosis of papillary thyroid carcinoma. Material and Methods: Expression of cytokeratin-19 was tested on formalin-fixed, paraffin-embedded tissues from 380 surgically resected thyroid lesions including hyperplasic nodules (n= 243), granulomatous thyroiditis (n= 3), lymphocytic (n= 53) and Hashimoto's thyroiditis (n= . . . 11), follicular adenomas (n= 17), Hurthle cell adenomas (n= 4), well-differentiated thyroid tumor with follicular architecture of uncertain malignant potenti al (n= 1), papillary carcinomas (n= 45), follicular carcinoma (n= 1), insular carcinoma (n= 1), and medullary carcinoma (n= 1). The immunoreactivity was scored as negative, 1+, 2+, 3+, and 4+, based on the extent of the reaction regardless of previous diagnosis. Results: Positive reaction with cytokeratin-19 was denoted in all of the 45 cases of papillary carcino mas with scores of 4+, 3+ and 2+ and the ratios were 57.8% (26/45), 33.3% (15/45) and 8.9% (4/45), respectively. There seemed to be a strong diffuse cytoplasmic reactivity with cytokeratin-19 in papillary thyroid carcinomas. The sensitivity and specificity for cytokeratin-19 in papillary carcinomas among neoplastic thyroid lesions were 91.8% and 86.2%, respectively. Conclusion: In additi on to careful histological evaluation, cytokeratin-19 seems useful for the diagnosis of papillary thyroid carcinomas. Copyright © 2009 by Türkiye Klinikleri Daha fazlası Daha az

Onak Kandemir N. | Barut F. | Dogan Gün B. | Solak Tekin N. | Hallaç Keser S. | Oguz Özdamar Ş.

Article | 2013 | Case Reports in Medicine2013 , pp.42 - 47

Aim. Cavernous hemangioma-like Kaposi sarcoma is a rare morphologic type of Kaposi sarcoma. So far there are no cases in the literature defining the histological features of this morphologic spectrum in detail. In this study we presented two classical-type cutaneous Kaposi sarcoma cases with histologic findings resembling cavernous hemangioma in company with clinical and histopathological data. Cases. One hundred and eighty-five classical-type cutaneous Kaposi sarcoma lesions in 79 patients were assessed retrospectively in terms of histopathological features. Findings of two cases showing features of cavernous hemangioma-like Kaposi . . . sarcoma whose clinical data could be accessed were presented in accompany with the literature data. Both cases were detected to have bluish-purple, protruded, irregularly bordered cutaneous lesions. Histopathological examination revealed a lesion formed by cavernous hemangioma-like vascular structures organized in a lobular pattern that became dilated and filled with blood. Typical histological findings of early-stage KS, consisting of mononuclear inflammation, extravasated erythrocytes, and a few immature vascular structures in superficial dermis, were observed. All cases were serologically HIV-1 negative. A positive reaction with HHV-8, CD31, CD34, and D2-40 monoclonal antibodies was identified at both cavernous hemangioma-like areas and in immature vascular structures. Results. Cavernous hemangioma-like Kaposi sarcoma is a rare Kaposi sarcoma variant presenting with diagnostic challenges, that may be confused with hemangioma. As characteristic morphological features may not be observed in every case, it is important for diagnostic purposes to show immunohistochemical HHV-8 positivity in this variant. © 2013 Nilüfer Onak Kandemir et al Daha fazlası Daha az

Onak Kandemir N. | Barut F. | Barut A. | Birol İ.E. | Dogan Gun B. | Ozdamar S.O.

Article | 2019 | Scientific Reports9 ( 1 ) , pp.42 - 47

Podoplanin, a reliable marker of lymphatic endothelium, is a mucin-type transmembrane protein. Although the human placenta is devoid of a lymphatic system, chorionic villous stromal (CVS) cells express podoplanin. In this study, the pattern of podoplanin expression in normal and pathological placental tissues and the biological role of podoplanin were investigated. In total, 198 placental tissues belonging to 184 patients, seen at the Department of Pathology of Bulent Ecevit University Education and Research Hospital, Zonguldak, Turkey, were evaluated histopathologically and determined to meet the study criteria. The tissues were as . . .signed to control, cisternal placental disorders, inflammation and hypoxic-ischemic pathology groups. Podoplanin expression in CVS cells was graded from 0 to 3 depending on the staining intensity, as determined by an immunohistochemical evaluation of chorionic villi in the most intensively stained tissue region. Podoplanin levels in control CVS cells increased in parallel with placental maturation, whereas in molar pregnancies podoplanin expression was lower than in control tissues. In the acute placental inflammation group, podoplanin immunoreactivity was similar to that in the control group, whereas in the preeclampsia group, podoplanin expression was higher than in all other groups. Our study showed an increase in podoplanin expression in CVS cells during pregnancy. In preeclamptic patients, the increase in podoplanin expression may be a response to hypoxic-ischemic conditions, whereas in molar pregnancies the decrease in podoplanin levels may cause villous swelling by disrupting intercellular fluid homeostasis. © 2019, The Author(s) Daha fazlası Daha az

Onak Kandemir N. | Bektaş S. | Barut F. | Yurdakan G. | Bahadir B. | Dogan Gün B. | Özdamar Ş.O.

Article | 2010 | Turk Patoloji Dergisi/Turkish Journal of Pathology26 ( 3 ) , pp.230 - 237

Objective: Fine needle aspiration cytology is the first step in the diagnosing breast lesions. This study evaluated factors causing false-negative and false-positive diagnoses when evaluating breast lesions using this technique. Material and Method: In this study, we retrospectively examined 511 breast diagnoses, based on Fine needle aspiration cytology specimens, made in the Medical School of Zonguldak Karaelmas University, Department of Pathology, between 2002 and 2009. Factors affecting the reliability of fine needle aspiration cytology were evaluated by comparing the cytological and biopsy diagnoses and using the clinical parame . . .ters in the diagnosis of breast lesions. Result: In our series, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of fine needle aspiration cytology were 77%, 99%, 95%, 93%, and 95%, respectively. The false-negative diagnosis rate was 4% and the false-positive diagnosis rate was 1%. Conclusion: Sampling errors and erroneous interpretation of cellular monomorphism are the most important reasons for false-negative diagnosis results in the evaluation of breast lesions with fine needle aspiration cytology. Increased cellularity and reactive cell atypia in benign proliferative breast lesions are the most frequent reasons for false-positive diagnosis Daha fazlası Daha az

Onak Kandemir N. | Barut F. | Yurdakan G. | Doğan Gün B. | Birol İ.E. | Özdamar Ş.O.

Article | 2017 | Turk Onkoloji Dergisi32 ( 4 ) , pp.165 - 168

Kaposi’s sarcoma (KS) is a vascular tumor with different epidemiological, clinical, and morphologic features, and KS-associated herpes virus plays role in its etiology. In the pathogenesis of these tumors, inflammatory, immunological, and oncogenic factors are closely related to each other. Classic KS is characterized by cutaneous lesions and mild clinical course. However, with the addition of various factors to the disease process, KS lesions can occur in unusual locations and cause unexpected clinical symptoms. In this study, we present a case of gastrointestinal system involvement in KS and lymphadenopathic KS following interstit . . .ial lung disease and steroid treatment in a 72-year-old male patient who was treated for cutaneous classic KS for 10 years. Histopathologic differential diagnosis of KS lesions seen in unusual localizations is discussed in the context of literature. © 2017, Turkish Society for Radiation Oncology Daha fazlası Daha az

Onak Kandemir N. | Barut F. | Yurdakan G. | Bayar Ü. | Özdamar Ş.O.

Article | 2010 | Turk Patoloji Dergisi/Turkish Journal of Pathology26 ( 1 ) , pp.85 - 88

Heterotopic pregnancy is a very uncommon entity with a difficult preoperative diagnosis. In the present study, we presented an ovarian heterotopic pregnancy case, clinically mimicking endometrioma developed in a 33-year-old female following an in vitro fertilization procedure. The importance of clinical, histopathological, and immunohistochemical examinations in the diagnosis of heterotopic pregnancy are emphasized.