Şevket Ruacan
Hacettepe University
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Publication
Featured researches published by Şevket Ruacan.
The Journal of Pediatrics | 1989
Sevgi Yetgin; Şinai Özsoylu; Şevket Ruacan; Gülsevin Tekinalp; Faik Sarialiolu
This study was aimed at detecting the early appearance of myelofibrosis by bone marrow biopsy examination in children with vitamin D-deficiency rickets. Twelve children, aged 4 to 18 months, were evaluated. Only a minimal increase of the reticulin was shown in rachitic children without anemia in whom no other laboratory evidence of myelofibrosis was present. Early signs of myelofibrosis with increase of reticulin were present in rachitic infants with anemia. In patients of the same age with iron deficiency anemia, the bone marrow reticulin findings were normal. Bone marrow biopsy after successful treatment of rickets could be repeated in one patient with myelofibrosis; results indicated that the myelofibrosis with anemia associated with vitamin D-deficiency rickets is reversible by vitamin D treatment.
Clinical Neurology and Neurosurgery | 1996
Mehmet Turgut; Nejat Akalan; Tunçalp Özgen; Şevket Ruacan; Aykut Erbengi
Five children with tuberous sclerosis and intracranial tumors were surgically treated at Neurosurgery Department of Hacettepe University School of Medicine. Two of the five patients presented with the giant cell astrocytoma filling the third ventricle. Direct surgical intervention and tumor removal was carried out in all four patients (three with a total surgical resection and one with a subtotal resection) and cerebrospinal fluid shunting procedure in one. Histopathological examination revealed giant cell astrocytomas in four patients. Postoperatively, one died and the rest four patients survived with minor focal neurologic difficulties. The surgical results and the changing concepts in the treatment of tuberous sclerosis are discussed and the literature is reviewed.
Acta Neurochirurgica | 1993
Oguz Cataltepe; Ozcan Oe; R. Onur; B. Demirhan; Şevket Ruacan; Aykut Erbengi
SummaryA new experimental model was designed in which the regeneration of rat femoral nerve across a 8 mm excised gap was investigated after insertion of the distal and proximal stumps into the anatomically and functionally intact femoral artery (AIAB). This model was compared with groups of free artery and autologous nerve grafting. After a period of 12 weeks, a histological and electrophysiological analysis was carried out, which demonstrated that the AIAB and autologous nerve grafting group had a significantly higher percentage of regeneration compared with the free artery-graft group. The nerve regeneration and intraneural vascular reconstruction that occured within AIAB group were more successful than those that occured in the artery and nerve-grafting groups.
Pediatric Hematology and Oncology | 2004
M. Tezer Kutluk; Bilgehan Yalçın; Canan Akyüz; Ali Varan; Şevket Ruacan; Münevver Büyükpamukçu
Files of 133 children with Ewing sarcoma (median age 10 years) were reviewed. Frequent primary sites were extremities, trunk, pelvis, and cranium. Half of 43 patients with metastases had disease in the lungs. Ten-year overall and event-free survival rates were 31% and 19%, respectively. Five-year overall survival rates were 42% in localized and 15% in metastatic disease (p <. 0001); 66% in cases with primary tumors < 8 cm and 29% in larger tumors (p =. 013). VAC (vincristine, actinomycine D, and cyclophosphamide) regimens with anthracyclines resulted in better survival. Presence of distant metastases, large primary tumors, and pelvic localization were related to poor prognosis. Novel therapeutic approaches are needed to produce better results, especially in high-risk patients.
American Journal of Hematology | 1999
Nurullah Zengin; Ayse Kars; Arzu Sungur; Neslihan İnci Zengin; Mutlu Hayran; Gülten Tekuzman; Emin Kansu; Şevket Ruacan; Firat D
Although bone marrow biopsy pattern (BMBP) has long been suggested to be an independent prognostic factor in chronic lymphocytic leukemia (CLL), conflicting reports continue to appear in the literature. To investigate this issue we retrospectively reviewed 70 CLL patients who had undergone bone marrow biopsy at the time of diagnosis in a multivariate Cox regression analysis together with other prognostic factors. There were 51 (72.8%) males and 19 (27.2%) females with a median age of 60 years (range, 38–77). The median follow‐up time was 24 months (range, 1–76), and median survival was 44 months. Thirtyfour patients (48.6%) had diffuse and 36 patients (51.4%) had nondiffuse BMBP (14 nodular, 11 interstitial, and 11 mixed). The median survival for diffuse and nondiffuse BMBP groups were 17 and 53 months, respectively (P= 0.05). Sixteen patients (22.9%) had stage A, 28 (40.0%) stage B, and 26 (37.1%) stage C disease according to the Binet system, and four patients (5.7%) had low‐risk, 39 (55.7%) intermediate‐risk, and 27 (38.6%) high‐risk disease according to the modified Rai staging system. The difference between the median survivals of patients in different stages was statistically significant (P < 0.0001). The BMBP and staging systems that are thought to be significant predictors of prognosis were used to build a multivariate Cox proportional hazard model. BMBP was not found to add additional information to the prognostic value of the staging systems. Our results underline two points: first, the significance of BMBP must be investigated in multivariate analysis including the stage, and second, BMBP is not a dynamic prognostic parameter, it is an index of tumor burden and does not add any prognostic information beyond that provided by clinical stage. Am. J. Hematol. 62:208–211, 1999.
Leukemia & Lymphoma | 2001
Ayşegül Hasegelj Üner; Huseyin Abali; Hüseyin Engin; Ayteion Akyol; Şevket Ruacan; Ersin Tan; Ibrahim Gullu; Kadri Altundag; Nilüfer Güler
Myasthenia gravis (MG) is an autoimmune neuromuscular junction disease. An association between thyrnic epithelial neoplasms and MG is well known. However, it is rarely associated with hematologic malignancies. In particular, very few cases of lymphoblastic lymphoma involving the thymus and MG have been reported. Here we report a case T-cell lymphoblastic lymphoma involving the thymus who developed MG after the initial diagnosis. The patient initially presented with a mediastinal mass which was diagnosed as lymphoblastic lymphoma. MG was diagnosed during leukemic relapse in this patient and was based on clinical presentation and neurophysiologic studies including single fiber electromyography (EMG) and repetitive nerve stimulation tests. In contrast to the other cases with such an association, the myasthenic symptoms presented nine months after the diagnosis of lymphoma by thymectomy. The patient had a highly aggressive clinical course and was resistant to various chemotherapy regimens.
Childs Nervous System | 1991
Ismail H. Tekkök; Kadir Tahta; Aykut Erbengi; Münevver Büyükpamukçu; Şevket Ruacan; Meral Topçu
An unusual case of primary extranodal Burkitts-type lymphoma of the frontal base dura and adjacent bone with intradural invasion is reported in a 5-year-old child who presented with unilateral loss of vision in the left eye. Tissue diagnosis was obtained through a craniotomy and the patient received radiotherapy plus intravenous and intrathecal chemotherapy. The tumor regression and improvement in vision was well documented by means of CT and visual evoked potential studies (VEP). A review of the literature on this exceptionally rare tumor is presented.
Leukemia Research | 1997
Zafer Baslar; Gülten Aktuǧlu; Zahit Bolaman; Filiz Büyükkeçeci; Sefer Gezer; Emin Kansu; Rikkat Koçak; Ercument Ovali; Şevket Ruacan; Deniz Sargin; Ahmet Tunali; Nukhet Tuzuner; Birsen Ülkü
The incidence of aplastic anemia among hospitalized adult patients was prospectively determined in this first study in Turkey. New cases of aplastic anemia among patients 14 years and older who were admitted to the study centers were included in a 3 year survey. Seventy-three patients fulfilled the diagnostic criteria, yielding a mean annual incidence rate of 1.14 cases in 10(3) admissions. The male-to-female ratio of the cases (1.6:1) differed from the almost equal ratio of the larger population of Turkey. The median age was 30 years and females were younger at diagnosis. The age distribution of the cases was different from that of the population; showing two incidence peaks in both sexes. The majority of the patients (89%) had severe disease.
Oral Surgery, Oral Medicine, Oral Pathology | 1990
Haviye Çelenligil; Emin Kansu; Şevket Ruacan; Kenan Eratalay; Murat Irkec
Primary Sjögrens syndrome (SS) is an autoimmune disease resulting from lymphocyte infiltration of lacrimal and salivary glands (SG). This study was designed to investigate the peripheral blood (PBL) and SG lymphocytes in 14 patients with primary SS and control subjects. With the use of monoclonal antibodies, cells were stained to identify T-cells and T-cell subsets (T-helper and T-suppressor) and cells positive for HLA-DR antigen, whereas B cells were determined by the Smlg (surface membrane immunoglobulin) method. Lymphocytes in SG biopsy specimens were characterized by means of monoclonal antibodies and the immunoperoxidase technique. In the peripheral blood lymphocytes, there was a significant reduction in T cells and suppressor T cells. T lymphocytes and mostly helper T cells were predominant around the ducts and within the lymphocytic infiltrates in the minor SG biopsy samples of patients with SS. Suppressor T cells and B cells were found in fewer numbers, HLA-DR(+) cell populations had increased, and IgG- and IgA-bearing plasma cells were also present within the infiltrates. These results may contribute to our understanding of the immunopathogenesis of primary SS.
Medical Oncology | 2001
Huseyin Abali; M. Kadri Altundag; Hüseyin Engin; Ozden Altundag; Alev Turker; Aysegul Uner; Şevket Ruacan
The differential diagnosis of eosinophilia may sometimes be difficult. Eosinophilia may occur in a diverse array of conditions from parasitic infestations to malignacies. Idiopathic hypereosinophilic syndrome has also been described. A 65-year-old male patient presenting with eosinophilia of obscure etiology is described in the present report. Three years after the diagnosis of eosinophilia, metastatic anaplastic carcinoma of unknown primary was detected. Differential diagnosis is disscussed briefly. It is stressed that patients with hypereosinophilia of unknown etiology must be screened for malignancy regularly during follow up.