Sinan Sözen
Gazi University
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Publication
Featured researches published by Sinan Sözen.
International Urology and Nephrology | 1999
Kenan Isen; Bora Küpeli; Zafer Sinik; Sinan Sözen; Ibrahim Bozkirli
We investigated the efficacy of prophylactic use of single dose oral ofloxacin and trimethoprim-sulfamethoxazole regimens for transrectal prostate biopsy in 110 men. In the ofloxacin, trimethoprim-sulfamethoxazole and control groups, urinary infection was found in 2 (4.76%), 3 (6.66%) and 6 (26.08%) patients, respectively. Both of these antibiotic regimens produced a statistically significant reduction in urinary infection (p<0.02, p<0.05).Our study indicates that single dose fluoroquinolone or trimethoprimsulfamethoxazole prophylaxis seems to be effective, practical and economical.
European Urology | 1999
Sinan Sözen; Hasan Biri; Zafer Sinik; Bora Küpeli; Turgut Alkibay; Ibrahim Bozkirli
Objective: To assess sensitivity, specificity, accuracy, positive predictive value and negative predictive value of nuclear matrix protein 22 (NMP22) test, BTA stat test and cytology in the urine of patients with a spectrum of urologic conditions, including bladder cancer. Methods: A total of 140 patients (40 with bladder cancer) provided a urine sample which was divided into appropriate aliquots for each of the tests cited above. The endoscopist, pathologist, cytologist and the person performing BTA stat test and NMP22 test were blinded as to the results of the other tests. Results: Receiver-operating characteristics curve interpretation determined that 12.0 U/ml was an optimal reference value for NMP22 to detect transitional cell carcinoma of the bladder in this patient group. Comparative results demonstrate a clear superiority of NMP22 and BTA stat tests in sensitivity in bladder cancer detection (p < 0.01), while cytology and NMP22 were better than BTA stat test in specificity (p < 0.05). Conclusions: NMP22 and BTA stat test results represented significant improvement over urinary cytology for detection of transitional cell carcinoma. The sensitivities of NMP22 and BTA stat tests for detection of transitional cell carcinoma in this group of patients were as much as twice that of cytology. When the cutoff value of urinary NMP22 was set at 12.0 U/ml, NMP22 was more accurate than the other tests (p < 0.05).
Journal of Endourology | 2003
Sinan Sözen; Bora Küpeli; Lütfi Tunç; Çağrı Şenocak; Turgut Alkibay; Üstünol Karaoğlan; Ibrahim Bozkirli
PURPOSE To evaluate the results of pneumatic lithotripsy (PL) with ureteroscopy in the treatment of ureteral stones. PATIENTS AND METHODS We reviewed, retrospectively, the records of 500 patients (366 male, 134 female) with ureteral calculi treated by PL with the Swiss Lithoclast. Of these patients, 124 (24.8%) were treated primarily and 376 (75.2%) were treated secondarily after unsuccessful extracorporeal shockwave lithotripsy (SWL). The results were evaluated 3 months after treatment by excretory urography, ultrasonography, or both. RESULTS The over-all stone-free and fragmentation rates were 94.6% and 96.8%, respectively. These values were 97.1% and 98.5% for stones <or=10 mm and 83.7% and 89.1% for stones >10 mm, respectively. The main complications were stone migration (2.0%), urosepsis (3.0%), and ureteral perforation (1.4%). CONCLUSIONS While SWL is generally excepted as a first-line treatment option in ureteral stones because of its noninvasive nature, in situ lithotripsy, and especially PL, has higher success rates with minimal morbidity. Thus, PL seems to be a good alternative in patients in whom SWL was unsuccessful or not indicated and in patients who need early stone removal.
Cancer Biology & Therapy | 2004
I. Durak; Hasan Biri; Erdinç Devrim; Sinan Sözen; Aslıhan Avcı
Aim: Investigation of possible effects of aqueous extract of urtica dioica leaves on adenosine deaminase activity in prostate tissue from patients with prostate cancer. Methods: Ten prostate tissues from patients with pathologically proven localized prostate cancer (Gleason scores 4 to 7) were used in the study. In the tissues, ADA activities with and without preincubation with different amounts of urtica dioica extracts were performed. Results: Aqueous extract of urtica dioica results in significant inhibition on adenosine deaminase (ADA) activity of prostate tissue. Conclusion: ADA inhibition by urtica dioica extract might be one of the mechanisms in the observed beneficial effect of urtica dioica in prostate cancer.
Urologia Internationalis | 2002
Sinan Sözen; Cem Akbal; Cenk Sokmensuer; Sinan Ekici; Haluk Ozen
Introduction: Our objective was to evaluate the feasibility and value of microstaging in pT1 transitional cell carcinoma (TCC) of the bladder in a well-defined group of patients treated with transurethral resection (TUR) only. Materials and Methods: The clinical records of 152 patients who underwent TUR for the treatment of primary superficial TCC of the bladder between 1983 and 1997 were reviewed. Patients with primary carcinoma in situ and who received adjuvant intravesical treatments were excluded from study. We subclassified the pT1 tumors into two groups according to muscularis mucosae (MM) invasion (pT1 and pT1b). The recurrence and progression rate of cancers was analyzed according to the stage, grade, multiplicity and tumor size. Mean follow-up was 68 months. Estimation of the cumulative distribution of the disease-free interval in separate groups was calculated according to the Kaplan-Meier method. Multivariate analysis of the data was performed by using Cox regression method. A value of p < 0.05 was taken to be statistically significant with odds ratios. Results: Of the 152 patients, tumor stage was pTa in 62 (40.8%) patients and pT1 in 90 (59.2%) patients. Among those pT1 tumors, MM was identified in 50 (55.5%) of cases (pT1a = 34, pT1b = 16). In the remaining 40 (44.5%) patients, MM could not be assessed. Kaplan-Meier analysis revealed that recurrence and progression were statistically significant for stage, multiplicity and grade of tumor. However, multivariate analysis revealed that stage was the only prognostic factor for recurrence and progression (p = 0.0001). Conclusion: The present study underscores the fact that pT1b tumors have a distinct natural history. If initial conservative treatment is selected, the patients must be followed very cautiously.
Urology | 2009
Cenk Acar; Serhat Gürocak; Sinan Sözen
Sex cord-stromal tumors (SCST) are rare testicular tumors. However, as 10%-12% of SCST are malignant and 20% are metastatic at initial diagnosis, establishment of protocols for diagnosis and follow-up carries most importance. The standard treatment method is inguinal orchiectomy and testis-sparing surgery is recommended for certain conditions. The studies show that retroperitoneal lymph node dissection is seemingly more of a staging tool and aiding to determine the follow-up protocol. The first 2 years are rather important in the follow-up of the disease. Although follow-up protocol could be more vigorous for patients with malignant clinicopathologic features and metastatic disease, it can be determined individually according to the aggressive properties of the disease and patient status.
Urologia Internationalis | 2009
Turgut Alkibay; Sinan Sözen; Serhat Gürocak; İpek Işık Gönül; Aylar Poyraz; İyimser Üre
Objectives: Our aim was to review our pathological archive to find out the actual incidence of micropapillary pattern (MPP) in our urothelial carcinoma patient population and determine its correlation with clinical outcome. Patients and Methods: 14 out of 170 cases with complete clinical follow-up were clinicopathologically analyzed. The extent of MPP was determined as tumor percentage. Results: 12 further cases with MPP were defined in the review. The percentage of patients with positive MPP increased in parallel to the tumor stage. There was no considerable difference between MPP-positive and MPP-negative groups according to the progression rates in non-muscle-invasive and muscle-invasive groups. Progression-free survival was much shorter in MPP cases, but again without statistical significance. Also, there was no significant relation between percentage of MPP and progression-free survival. Conclusions: Awareness of pathologists about MPP and its highly possible relation with aggressive behavior must be raised, as it may be more common than reported. A multicentric review of a large number of cases with MPP is needed for a better definition of its biological behavior. Focal MPP cases may have a better prognosis but this needs to be confirmed.
Oncology Letters | 2014
Venhar Gürbüz; Ece Konac; Nuray Varol; Akin Yilmaz; Serhat Gürocak; Sevda Menevse; Sinan Sözen
The aim of the present study was to analyze the molecular mechanisms involved in blocking the signaling pathway and the effects of this on the progression of prostate cancer (CaP) cells in vitro. LNCaP human CaP cell line was stimulated with interleukin-6 (IL-6) in the presence/absence of Janus kinase (JAK) 2 (AG490), signal transducer and activator of transcription 3 [(STAT3) S3I-201] inhibitors and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Cytotoxic activity, the activation of phosphorylated (p)-STAT3 protein, caspase (CASP) 3 activity at protein level, vascular endothelial growth factor (VEGF) A, VEGFC, vascular endothelial growth factor receptor 2, STAT3, matrix metalloproteinase-2, myeloid cell leukemia sequence 1 (MCL-1), CASP8 and CASP9 messenger RNA (mRNA) levels were determined. Morphology and apoptosis were confirmed by DAPI staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. IL-6 rapidly induced the phosphorylation of STAT3 in a dose- and time-dependent manner with a peak expression at 3 h at a concentration of 25 ng/ml. In addition, AG490 (50 μM) and S3I-201 (300 μM) inhibited STAT3 activation. Western blotting results revealed that p-STAT3 protein expression decreased significantly with AG490 and S3I-201 treatment in LNCaP cells. AG490 and S3I-201 induced the downregulation of VEGFA, MCL-1 and STAT3 and the upregulation of CASP8 and CASP9 mRNA transcription levels. In addition, the inhibitors increased the level of CASP3 protein. Combinations of AG490- and S3I-201-TRAIL did not result in an increase in this effect. Parallel results were found by DAPI staining and TUNEL assay. To the best of our knowledge, this is the first study to investigate the possible clinical use of AG490 or S3I-201, together with the reduced use of chemotherapeutic agents with high cytotoxicity, for their ability to exert an apoptotic effect, targeting the JAK/STAT3 pathway.
Urologia Internationalis | 2007
Ilker Sen; Metin Onaran; Mustafa Tan; Cenk Acar; Ahmet Camtosun; Sinan Sözen; Ibrahim Bozkirli
Introduction: Of late, little data is available concerning factors affecting female sexual function. In the present study, we evaluated the effects of overactive bladder (OAB) syndrome symptoms on female sexual function. Materials and Methods: 40 patients with OAB symptoms and 40 age-matched women as a control group were evaluated using the Female Sexual Function Index (FSFI) for sexual function. According to the presence of urge incontinence, women with OAB were also divided into wet and dry groups. After completion of the forms, groups were compared. Results: Although scores of all domains of FSFI (desire, arousal, lubrication, orgasm, satisfaction, pain and total) in the OAB group were found to be lower than in the control group, only ‘desire’ was found to be significantly different (p = 0.035). The FSFI scores of the OAB-dry and OAB-wet group were similar to each other. Conclusion: The results indicate that there is a trend toward lower sexual function scores in women with OAB compared to controls.
American Journal of Clinical Oncology | 2001
Haluk Ozen; Cem Aygün; Ali Ergen; Sinan Sözen; Fazil Tuncay Aki; M. C. Uygur
The authors evaluated the prostate cancer detection rate in Turkish patients with prostate-specific antigen (PSA) levels of 4 ng/ml to 10 ng/ml and who had normal digital rectal examination (DRE) findings. They also aimed to evaluate the value of PSA density and percent free PSA in minimizing unnecessary prostate biopsies for these PSA ranges. This prospective study included 134 consecutive men referred for early prostate cancer detection or lower urinary tract symptoms. All men underwent transrectal ultrasound with systematic sextant needle biopsies. The ability of PSA density and percent free PSA to improve the power of PSA in the detection of prostate cancer was evaluated with statistical analyses as well as receiver operating characteristics curves. Among the 134 men, 124 (92.5%) had a benign histology and 10 (7.5%) had cancer diagnosed on the initial biopsies. Despite the disappointing results in regard to the sensitivity and specificity of PSA derivatives alone, the combination of PSA density and percent free PSA significantly increased the area under the curve compared with the use of each test alone. To increase the specificity of PSA in this patient population, the authors recommend combining two PSA derivatives in deciding whether to perform a biopsy. In a PSA range of 4 ng/ml to 10 ng/ml and with normal DRE, a percent free PSA < 21% and a PSA density > 0.18 yields highest specificity with 90% sensitivity.