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Featured researches published by Haydar Durak.


The Journal of Urology | 2012

Core Length in Prostate Biopsy: Size Matters

Can Öbek; Tunkut Doganca; Sinan Erdal; Sarper Erdoğan; Haydar Durak

PURPOSE The diagnostic yield of prostate biopsy is limited. Increasing the number of cores enhances the cancer detection rate by sampling additional sites and obtaining more tissue. An alternative way to inspect more tissue would be to obtain longer cores. However, the impact of biopsy core length on cancer detection rate is an undervalued topic. We assessed the role of biopsy core length in prostate biopsy and determined the minimal tissue length to serve as quality assurance. MATERIALS AND METHODS We retrospectively analyzed the records of 331 patients who underwent transrectal ultrasound guided initial prostate biopsy with 12 to 18 cores. The biopsy procedure and pathological evaluation were standardized. Core length was compared in patients with vs without cancer. Statistical analysis was done to determine a minimally acceptable cutoff for biopsy length. RESULTS We analyzed data on 245 patients. The overall cancer detection rate was 30.2%. Mean core length in patients with vs without cancer was 12.3±2.6 vs 11.4±2.4 mm (p=0.015). Thus, core length was significantly longer in patients with cancer. Core length greater than 11.9 mm was associated with an increased prostate cancer detection rate (OR 2.57, 95% 1.46-4.52). The cancer detection rate for cores less vs greater than 11.9 mm was 23% vs 39%. CONCLUSIONS Needle core length is an important morphometric parameter of transrectal prostate biopsy that directly influences the cancer detection rate. Results suggest a core length of greater than 11.9 mm as a cutoff for quality assurance.


Burns | 2000

An unusual long-term complication of burn injury : malignant fibrous histiocytoma developed in chronic burn scar

Akın Yücel; Şükrü Yazar; Cuyan Demirkesen; Haydar Durak; Sergülen Dervişoğlu; Muzaffer Altıntaş

Development of malignant tumors in chronic burn wounds is a well-known complication. These tumors are almost always squamous cell carcinomas, although other types of malignancies such as basal cell carcinoma, malignant melanoma and sarcomas can be seen rarely. There are only three previously reported cases of malignant fibrous histiocytoma developed in chronic burn scar in the literature. Two cases with malignant fibrous histiocytoma developed in chronic, badly treated burn wounds are presented. One of the tumors was multifocal and overexpression of the p53 gene was present. Both tumors were excised widely and skin grafted. Regional lymph node dissection was performed in one case. One of the patients died due to tumor recurrence and lymphatic metastases. These cases represent a very uncommon complication of burn injury and indicate the importance of the appropriate primary treatment of the burn wound.


Biological Trace Element Research | 2012

Association of Pb, Cd, and Se Concentrations and Oxidative Damage-Related Markers in Different Grades of Prostate Carcinoma

Savas Guzel; Lebriz Kiziler; Birsen Aydemir; Bulent Alici; Süleyman Ataus; Abdullah Aksu; Haydar Durak

Prostate cancer is known to be affected by the heavy metal levels and oxidative damage of the body, yet there are very few studies which look into the way it occurs. The aim of this study was to determine whether blood and tissue lead (Pb), cadmium (Cd), and selenium (Se) levels are associated with oxidative damage in the context of prostate cancer progression and development. Seventy-nine patients comprising 25 patients with benign prostatic hypertrophy (BPH), 23 patients with malignant prostatic carcinoma (malign Ca), 16 patients with low-grade prostatic intraepithelial neoplasia (LGPIN), and 15 patients with high-grade prostatic intraepithelial neoplasia (HGPIN) diagnosed on the basis of their clinical profile, transrectal ultrasonography, and histopathology were included in this study. Cd and Pb levels in whole blood were found to be increased in patients with HGPIN compared with the BPH group; also, the levels of Cd in whole blood and tissue were found to be increasing in patients with malign Ca, unlike BPH patients. Moreover, the levels of malondialdehyde (MDA) in plasma and tissue were significantly increased in malign Ca, LGPIN, and HGPIN than those in BPH. However, the levels of tissue Pb were found to be decreasing in BPH, unlike the malign Ca and HGPIN patients, and the levels of tissue protein carbonyls in malign Ca were significantly lower than those in HGPIN. The levels of tissue reduced glutathione (GSH) in malign Ca were significantly lower than those in BPH. Additionally, the levels of Se in serum and tissue in LGPIN were significantly lower than those in BPH. The serum Se levels in HGPIN were also significantly lower than those in BPH and malign Ca groups. Furthermore, the concentrations of serum Se in LGPIN were significantly lower than those in malign Ca. From the Pearson correlation analysis, there were significant positive correlations between tissue Cd and MDA levels in malign Ca, LGPIN, and HGPIN and between the tissue Pb and tissue MDA and protein carbonyl levels in malign Ca. Blood Pb and tissue Pb were also significantly positively correlated with plasma MDA and protein carbonyl levels in malign Ca. In addition, blood Pb was significantly positively correlated with tissue MDA and protein carbonyl levels in malign Ca, and a significant positive correlation was also found between blood Cd and plasma protein carbonyls and tissue MDA in LGPIN. We observed that altered prooxidant–antioxidant balance and heavy metal levels may lead to an increase in oxidative damage and may consequently play an important role in prostate carcinogenesis. These findings indicate that changes in the levels of Pb, Cd, Se, MDA, protein carbonyls, and GSH in the blood and/or tissue are related to the prostatic carcinoma development and progression, although triggering one of the mentioned changes is unknown; therefore, further study is required to determine the exact steps of the process and clarify the roles of different substances in order to obtain a more detailed explanation of the phenomenon.


Journal of Cancer Research and Clinical Oncology | 2013

Expression of MMP-1, MMP-9 and TIMP-2 in prostate carcinoma and their influence on prognosis and survival

Ferhat Ozden; Caner Saygin; Didem Uzunaslan; Bulent Onal; Haydar Durak; Hilal Aki

PurposeMatrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) participate in tumorigenesis, and their association with disease outcome is highly controversial. The present study investigates the influence of MMP-1, MMP-9 and TIMP-2 on different clinicopathologic variables and disease-free survival (DFS) of patients with prostate carcinoma.MethodsHundred and forty-five cases are included in the study, and levels of MMP/TIMP expressions are assessed in three tissue compartments (i.e., tumor, stroma and normal glands) with immunohistochemistry.ResultsMatrix metalloproteinase-1 expression in tumor cells was associated with lower Gleason scores, pretreatment prostate-specific antigen levels and lower incidence of vascular, perineural and extracapsular invasions. Moreover, MMP-9 positivity and TIMP-2 expression in normal glands were correlated with lower Gleason patterns and early stage at presentation. Expression of MMP in tumor cells and the presence of TIMP-2 in normal glands were associated with better DFS.ConclusionVariability of MMP/TIMP expressions from case to case makes it difficult to evaluate their impact on clinical outcome. However, these proteins might be new and promising targets for prostate cancer therapy in the future.


Journal of Surgical Research | 2008

The Effect of Halofuginone, a Specific Inhibitor of Collagen Type 1 Synthesis, in the Prevention of Pancreatic Fibrosis in an Experimental Model of Severe Hyperstimulation and Obstruction Pancreatitis

Adem Karatas; Melih Paksoy; Yusuf Erzin; Sinan Çarkman; Fadil Ayan; Fatih Aydogan; Hafize Uzun; Haydar Durak

BACKGROUND The aim of this paper is to assess the effects of halofuginone, a specific inhibitor of synthesis of collagen Type 1, on fibrogenetic process in an experimental model of early pancreatic fibrosis. METHODS Thirty rats were divided into three equal groups: group 1, sham laparotomy; group 2, severe hyperstimulation and obstruction pancreatitis (SHOP) with no treatment; group 3, SHOP with halofuginone treatment group. SHOP model was induced by complete pancreatic duct obstruction and daily cerulein hyperstimulation (50 microg/kg, intraperitoneally). Halofuginone was administered daily from the operative day (5 mg/kg, intraperitoneally). All of the animals were sacrificed, and blood and pancreatic tissue samples were obtained for biochemical and histopathological examination on the 5th postoperative day. RESULTS No mortality was observed in any group. Serum amylase, lipase, hyaluronic acid, and nitric oxide levels were significantly higher in groups 2 and 3 compared with group 1 (P < 0.05), but were significantly lower in group 3 compared with group 2 (P < 0.05). No significant differences were observed regarding serum malondialdehyde and glutathione levels between groups 1 and 3. Tissue hydroxyproline levels were found to be significantly higher in groups 2 and 3 compared with group 1 (P < 0.001), but were significantly lower in group 3 compared with group 2 (P < 0.001). Although tissue hydroxyproline levels were significantly higher in the halofuginone treatment group compared with the control group, histopathological evaluation did not reveal a significant difference between these groups regarding collagen deposition. When group 3 was compared with group 2, halofuginone significantly reduced inflammation and acinar atrophy in the pancreas as well (P < 0.05). CONCLUSION Halofuginone was found to be effective in reducing SHOP-related inflammation, acinar atrophy, and fibrosis in the pancreas.


Scandinavian Journal of Gastroenterology | 2006

Liver steatosis in hepatitis C positive hemodialysis patients and factors affecting IFN-2a treatment

Beytullah Yildirim; Haydar Durak; Resat Ozaras; Billur Canbakan; Perihan Ozkan; Gulsen Ozbay; Hakan Senturk

Objective. Hepatitis C virus (HCV) infection is endemic among hemodialysis (HD) patients. It is well known that HCV causes approximately 50% of hepatosteatosis in patients with normal renal function and that this rate is higher in patients infected with genotype 3. The aim of this study was to investigate the rate of steatosis, the regression in steatosis with interferon (IFN) treatment and factors affecting IFN treatment in hemodialysis patients with chronic hepatitis C (CHC). Material and methods. Thirty-seven HD patients with CHC were included in the study. All patients received hemodialysis treatment three times a week during the follow-up period. Patients were treated with 3 million units (MU) of IFN-α 2a monotherapy for at least 6 months. All patients were evaluated by liver biopsy before therapy and 16 were evaluated at 12-month follow-up. Results. Mean age of the 37 patients (23 M, 14 F) was 44±11.6 years and body mass index was 21.8±1.8 kg/m2. Twenty-eight of the patients included in the study (75.7%) were of genotype 1b. RNA response after treatment was 78.4% and sustained response after the follow-up period of 14.9±8 months was 54%. Total cholesterol values were directly proportional to RNA response (p<0.003) and inversely correlated with resistance to treatment (p<0.008). Triglyceride values were inversely correlated with resistance to treatment (p<0.041). At evaluation of steatosis scores in baseline liver biopsy, severe and mild to moderate steatosis was found in 3 (8.1%) and 16 (43.2%) patients, respectively. In 18 patients (48.7%) there was no steatosis. The rate of steatosis was found to be 44% in control biopsies. While there was no regression in the rates of steatosis (p=0.499), it was found that steatosis regressed after IFN treatment in two patients infected with genotype 3. No correlations were observed between HCV genotype, sustained response and liver steatosis. Conclusions. Response and sustained response rates of HD patients with HCV in a Turkish population were found to be high after IFN monotherapy. With the exception of two patients infected with genotype 3a, the rate of liver steatosis was found to be high and did not change after IFN treatment in HD patients with CHC.


Apmis | 2007

Expression of cyclooxygenase‐2, c‐kit, progesterone and estrogen receptors in uterine smooth muscle tumors: differential diagnosis

Nil Çomunoğlu; Haydar Durak; Cem Çomunoğlu; A. Işin Doğan Ekici; Ferda Ozkan; Elif Ulker Akyildiz; Şennur İlvan; Zerrin Calay; Nil Molinas

We examined the expression pattern of cyclooxygenase‐2 (COX‐2) and c‐kit in uterine smooth muscle neoplasms and tried to determine the role of these markers in differential diagnosis. Archival tissue from 64 patients with uterine smooth muscle neoplasms (20 leiomyomas (LMs), 22 atypical leiomyomas (ALMs), and 22 leiomyosarcomas (LMSs)) was immunostained with antibodies against estrogen (ER) and progesterone receptors (PR), COX‐2 and c‐kit. 7 of 20 LM cases and 5 of 22 ALM cases were immunopositive for COX‐2, whereas none of the LMS cases stained immunopositive (p≤0.05). 4 of 20 LM cases and 5 of 22 ALM cases were immunopositive for c‐kit, whereas 15 of 22 LMS cases showed c‐kit immunopositivity (p≤0.05). In conclusion, very few LMs and ALMs show COX‐2 immunopositivity. LMSs usually do not express COX‐2. COX‐2 expression in smooth muscle tumors is not a prominent feature. Therefore, COX‐2 inhibitors may not be useful in LMS therapy. C‐kit was significantly expressed in uterine LMSs.


International Urology and Nephrology | 2006

Adult paratesticular myxofibrosarcoma: report of a rare entity and review of the literature.

Burak Özkan; Mustafa Ozguroglu; Hamdi Özkara; Haydar Durak; Zübeyr Talat

A case of 70 years old man with a slowly enlarging painful scrotal mass is herein reported. Computed tomography scan of the scrotum showed a homogenous and encapsulated mass, associated with the tunica albuginea. There was no evidence of any metastatic lesion(s). Orchidectomy was performed with high ligation of the spermatic cord. Histopathologic examination revealed a rare case of paratesticular myxofibrosarcoma. Complete surgical resection is the only curative treatment modality in the treatment of these low grade tumors. Adjuvant chemotherapy or radiotherapy are not recommended for paratesticular myxofibrosarcomas.


European Radiology | 2002

Abdominal leiomyosarcomas: radiologic appearances at various locations

Sebuh Kurugoglu; Gunduz Ogut; Ismail Mihmanli; Ugur Korman; Haydar Durak

Abstract. Leiomyosarcomas are soft tissue tumors that account for approximately 15% of all soft tissue sarcomas. Leiomyosarcomas may be located at almost any part of the abdomen but especially are more common in the retroperitoneum, followed by gastrointestinal tract and genital system. They develop mainly in adult life and are very rare in children. In this article, imaging findings of leiomyosarcomas in various abdominal locations are presented. Radiologic studies are capable of providing useful information on the localization, size, changes in the internal structure of the tumor, its extension and invasion. Leiomyosarcoma should be considered in the differential diagnosis in case of detection of a large, circumscribed, and heterogenous abdominal mass. Histopathologically, diagnosis of malignancy depends particularly on mitotic counts, size, rate of necrosis, and infiltrating margins.


Journal of Ultrasound in Medicine | 2016

Is There Any Difference Between Seminomas and Nonseminomatous Germ Cell Tumors on Shear Wave Elastography? A Preliminary Study

Atilla Suleyman Dikici; Mehmet Emin Er; Deniz Alis; Cesur Samanci; Fethi Emre Ustabasioglu; Cetin Demirdag; Haydar Durak; Fatih Kantarci; Ismail Mihmanli

OBJECTIVES The purpose of this study was to evaluate the ability of shear wave elastography (SWE) to differentiate seminomas from nonseminomatous germ cell tumors. METHODS Approval for this retrospective study was obtained from the local Ethics Committee of Istanbul University Cerrahpasa Medical School. Fifteen patients with malignant testicular lesions were examined by grayscale sonography, color or power Doppler sonography, and SWE between February 2011 and October 2015. The size of each lesion, Doppler signal parameters, echogenicity, presence of microlithiasis, unifocality or multifocality, and histopathologic findings were the main factors evaluated. RESULTS The mean age of the patients was 33 years (range, 25-55 years). There were no differences between seminomas and nonseminomatous germ cell tumors in terms of Doppler signals, echogenicity, microlithiasis, or focality. Only the homogeneous and heterogeneous echogenicity patterns differed significantly. However, a significant difference was evident in SWE-derived quantitative data. CONCLUSIONS Seminomas and nonseminomatous germ cell tumors do not differ significantly on grayscale or Doppler sonography, except in terms of homogeneity. However, SWE seems to differentiate seminomas from nonseminomatous germ cell tumors.The purpose of this study was to evaluate the ability of shear wave elastography (SWE) to differentiate seminomas from nonseminomatous germ cell tumors.

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