Abdurrahman Özgür
Marmara University
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Featured researches published by Abdurrahman Özgür.
International Urology and Nephrology | 2004
Abdurrahman Özgür; Fikret Fatih Önol; Levent Türkeri
Introduction: Initial diagnostic evaluation may provide information about the extent of disease after radical retropubic prostatectomy (RRP). The aim of this study was to investigate the predictive value of preoperative serum prostate specific antigen (PSA) level, local disease extension identified by transrectal ultrasound (TRUS), total number of positive biopsies and percentage of positive cores for cancer, as well as TRUS Biopsy Gleason score in determining the extent of disease in radical retropubic prostatectomy specimens. Materials and methods: A retrospective analysis was performed on 171 patients who underwent RRP from March 1993 to February 2003 for organ confined prostate cancer and whose follow-up data was accessible. The correlation of preoperative serum PSA level, local disease extension in TRUS, the total number of positive sextant biopsies and the percent of cores positive for cancer and Gleason score at TRUS biopsy specimen with the extent of disease at final pathology (Extra-capsular extension (ECE), seminal vesicle invasion (SVI), lymph node involvement (LNI) and surgical margin (SM) status on RRP specimens) were analyzed. Results: The median age of the patients was 65 years. The mean preoperative serum PSA level of all patients was 11.6 ± 1.2 (median 8.6) ng/ml. Histopathological evaluation of RRP specimens revealed 60 (35%) patients with ECE, 38 (22.2%) with SVI, 7 (0.04%) with LNI, and 58 (33.9%) had positive SM. Comparing the preoperative TRUS findings and postoperative evaluation of RRP specimens, the sensitivity of TRUS in predicting the ECE was 11.8% and specificity was 96%. Sensitivity of TRUS in predicting SVI was 9.8% and its specificity was 99%. With univariate analysis (sample t-test), Gleason score, percent of cores positive for cancer, and DRE were found to be predictive factors for extra-prostatic disease in RRP specimens. But with multivariate analysis (logistic regression test) Gleason score appears to be the most important and independent predictive factor for extra-prostatic disease in RRP specimens. Serum PSA levels and percentages of cores positive for cancer were also significant predictors of non organ-confined disease found at final pathology. Conclusion: Gleason score is the most important and independent predictive factor for extra-prostatic disease. Serum PSA levels and percentages of cores positive for cancer are the other important but non-independent predictive factors.
Urologia Internationalis | 2008
Abdurrahman Özgür; Fikret Fatih Önol; Feriha Ercan; Tufan Tarcan
Introduction: The effect of L-arginine on bladder tissue structure and function in a rat bladder injury model were investigated. Methods: 24 male Sprague-Dawley rats were used. The control group received a regular diet. The L-arginine group received oral L-arginine (1 g/day). The protamine sulfate (PS) group received intravesical PS every 48 h (0.5 ml, 5 mg/ml). L-Arginine was administered to the PS+L-arginine group in addition to PS. At the end of 1 week, bladder tissues were processed for histological and functional studies. Results: The PS group revealed urothelial damage with glycosaminoglycan layer irregularity and mast cell infiltration which was not evident in the PS+L-arginine group. 120 mM potassium and electrical field stimulation (EFS)-induced contractions in the PS group were significantly lower than in other groups, whereas carbachol-induced contractions were not significantly different. Relaxation responses of precontracted strips to EFS and isoproterenol did not reveal a significant decrease in the PS group, whereas L-arginine significantly enhanced these responses in PS-treated animals. Conclusions: Intravesical PS causes urothelial damage and inflammation that is associated with significant changes in rat bladder tissue contractility. Oral L-arginine treatment is found to prevent these histological and contractile alterations. Our findings may indicate the nitric oxide-cGMP pathway as a possible therapeutic target in various bladder diseases associated with urothelial damage.
Urologia Internationalis | 2006
Levent Türkeri; Yusuf Temiz; Abdurrahman Özgür; Fikret Fatih Önol
Introduction: The type of skin incision affects the course of surgery during radical nephrectomy. We investigated the efficacy of a new type of incision for the surgical approach to large renal masses. Patients and Methods: Fourty patients (23 males and 17 females, mean age 63 years) who underwent radical nephrectomy in our department between 2002 and 2004 were evaluated. The outcomes in the groups with chevron incision and abdominal wall flap incision (AFI) were compared in terms of greatest tumor diameter, operation duration, perioperative blood loss, postoperative complications, and duration of hospitalization. Statistical analysis was made by independent-samples t test. Results: Chevron incision was used in the first 15 patients, while subsequent 25 patients were operated via AFI. The operation duration was slightly longer in the AFI group (3.78 vs. 3 h); however, the mean largest tumor diameter was significantly greater in patients operated via AFI (11.3 vs. 7.4 cm, p < 0.05). The mean blood losses were 1,100 and 590 ml in the chevron incision and AFI groups, respectively (p < 0.05). There was no significant difference in terms of duration of hospitalization and postoperative morbidity. Conclusion: In our experience, AFI provides the best exposure and improved control of renal vessels and vena cava during radical nephrectomy and enables a safe dissection even in very large tumors with minimal blood loss.
Archivos españoles de urología | 2005
Fikret Fatih Önol; Abdurrahman Özgür; Levent Türkeri
OBJECTIVES In this study, we investigated the association of positive biopsy core percent (PBCP), as well as other preoperative factors, with prostate cancer outcomes in a cohort of consecutive patients with clinically localized prostate cancer who underwent RRP. METHODS Data from 203 patients who underwent RRP from March 1993 to May 2004 for clinically organ confined prostate cancer was analysed. The correlation of preoperative serum prostate specific antigen (PSA) level, biopsy Gleason score, total number of positive biopsies and PBCP with the extent of disease at final pathology and biochemical progression were analyzed. RESULTS The mean PBCP was 29.8+/-21.1 (median 25). Histopathological examination of the RRP specimens revealed ECE in 66 (32.5 %), SVI in 43 (21.2 %), LNI in 8 (4 %), and positive SM in 59 (29.1 %). Overall, only 9% of patients ( 18 of 203) had biochemical progression at a median postoperative follow-up of 22 months. Univariate analysis revealed serum PSA, biopsy Gleason Score, the number of positive cores and PBCP as predictive factors for extra-prostatic disease in RRP specimens. However, multivariate analysis revealed that biopsy Gleason score and serum PSA were the strongest independent predictive factors for extra-prostatic disease while percent positive biopsy cores carried significance in the prediction of ECE and SM positivity. The number of positive cores was not a predictor of non-organ confined disease. Preoperative serum PSA was the only prognostic factor for determination of biochemical failure. CONCLUSION Gleason score is the most important and independent predictive factor for extra-prostatic disease. The percentage of cores positive for cancer has significance only in the prediction of ECE and SM positivity. Further studies are needed before routine use of PBCP as one of the important preoperative prognostic factors.
International Urology and Nephrology | 2004
Abdurrahman Özgür; Alper Şişmanoğlu; Cenk Murat Yazici; Emine Coşar; Devrim Tezen; Yalçi İlker
Archivos españoles de urología | 2003
Abdurrahman Özgür; Y. Ilker; Levent Türkeri
International Urology and Nephrology | 2005
Y. Ilker; Abdurrahman Özgür; Cenk Murat Yazici
International Urology and Nephrology | 2005
Abdurrahman Özgür; N. Yalem Iker
Archivos españoles de urología | 2003
Abdurrahman Özgür; Tufan Tarcan; Ferruh Simsek; Rengin Ahiskali
Urologia Internationalis | 2006
Massimo Lazzeri; A.K. Taghizadeh; A. El Madani; P.R. Gard; C.-Y. Li; P.J. Thomas; S.P. Denyer; Seung-June On; Ja Hyeon Ku; Mehdi Salehipour; Abdolaziz Khezri; Valiallah Azizi; Mohsen Kroup; Mete Kaya; Mehmet Emin Boleken; Fadile Yildiz Zeyrek; Ilyas Ozardali; Turan Kanmaz; Ozcan Erel; Selçuk Yücesan; T.Y. Hosono; K. Kuratsukuri; Y. Nitta; K. Sugimura; T. Harada; T. Nakatani; Mete Kilciler; Selahattin Bedir; Fikret Erdemir; Ali Avci