Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Bulent Akdogan is active.

Publication


Featured researches published by Bulent Akdogan.


The Journal of Urology | 2006

Prognostic Significance of Bladder Tumor History and Tumor Location in Upper Tract Transitional Cell Carcinoma

Bulent Akdogan; Hasan Serkan Dogan; Saadettin Eskicorapci; Ahmet Sahin; I. Erkan; Haluk Ozen

PURPOSE We studied prognostic factors for 5-year disease specific and recurrence-free survival in patients treated for upper urinary tract transitional cell carcinoma. MATERIALS AND METHODS Since July 1987, 72 patients with a mean age of 58.9 years have undergone nephroureterectomy with bladder cuff excision. Median followup was 62.2 months (range 6 to 192). Patient age, sex, detection duration and mode, bladder tumor history, smoking habit, stone disease history, and tumor stage, grade and location were evaluated as prognostic factors. RESULTS Overall 5-year disease specific and recurrence-free survival rates were 74.9% and 67.8%, respectively. Univariate analysis revealed anemia, positive bladder tumor history, T stage, grade and tumor location in the upper tract as significant prognostic factors. On multivariate analysis T stage, grade and tumor location in the urothelium were the only significant variables for the 5-year disease specific and recurrence-free survival rates. CONCLUSIONS High tumor stage and grade, and ureteral location were significantly associated with worse disease specific and recurrence-free survival in patients with upper urinary tract transitional cell carcinoma. Our results may help define the patient groups that need adjuvant therapy and they may form a basis for further controlled studies.


Journal of Endourology | 2002

Antibiotic Prophylaxis in Percutaneous Nephrolithotomy: Prospective Study in 81 Patients

H. Serkan Dogan; Ahmet Şahin; Yeşim Çetinkaya; Bulent Akdogan; Ender Ozden; Sezer Kendi

PURPOSE To compare single-dose and short-course antibiotic prophylaxis protocols in percutaneous nephrolithotomy. PATIENTS AND METHODS Eighty-one patients with sterile urine preoperatively who underwent percutaneous nephrolithotomy were divided into two groups. The first group (N = 43) received a single intravenous dose of antibiotic (200 mg of ofloxacin) during anesthetic induction, and the second group (N = 38) received treatment doses of antibiotic (400 mg of ofloxacin per day) until the nephrostomy catheter was removed. The two groups were identical according to demographic and treatment characteristics. For each patient, microbiologic evaluation of extracted stones and urine samples was done. If patients developed fever in the postoperative period, blood and urine cultures were taken. Factors that might have affected the development of postoperative fever and infection were analyzed. RESULTS Nine patients in the first group had postoperative fever. Three had bacteriuria, and one had bacteremia. In the second group, eight patients had fever. One had bacteriuria and bacteremia. Nineteen patients (eleven in the first group, eight in the second) had positive stone cultures. No statistical difference was observed between the two groups in terms of bacteriuria, bacteremia, positive stone cultures, or postoperative fever. The febrile patients had longer operations with the use of more irrigation fluid and longer postoperative hospital stays. CONCLUSIONS In patients whose preoperative urine cultures are sterile, short-term prophylaxis has no advantage over single-dose prophylaxis as a means of preventing infection. The duration of surgery and the amount of irrigation fluid are significant risk factors for postoperative fever.


BJUI | 2004

Use of the holmium:YAG laser for ureterolithotripsy in children

Hasan Serkan Dogan; Serdar Tekgül; Bulent Akdogan; Mehmet Selcuk Keskin; Ahmet Sahin

To review our experience with rigid ureteroscopy and holmium:YAG laser for treating ureteric calculi in children.


Journal of Endourology | 2013

Prospective Comparative Study of Two Protocols of Antibiotic Prophylaxis in Percutaneous Nephrolithotomy

Emre Tüzel; Orhan Cem Aktepe; Bulent Akdogan

BACKGROUND AND PURPOSE Percutaneous nephrolithotomy (PCNL) is considered to be a clean-contaminated surgical procedure, and all patients are recommended to receive antibiotic prophylaxis before the operation to prevent septic events. The aim of the present study is to prospectively compare two different protocols of antibiotic prophylaxis in PCNL. PATIENTS AND METHODS Seventy-three patients with preoperative sterile urine were randomized into single-dose or short-course antibiotic prophylaxis groups. Patients in the first group (n=36) were given only a single dose of ceftriaxone during induction of anesthesia, while the second group (n=37) were given an oral third-generation cephalosporin after ceftriaxone until nephrostomy catheter withdrawal. For each patient, urine samples that were taken during initial access into the collecting system, as well as some stone fragments, were sent for culture and sensitivity analysis. Moreover, urine samples of the patients were cultured preceding nephrostomy catheter removal. Occurrence of perioperative infection related events was compared in both groups. RESULTS The demographic and treatment-related characteristics of both groups were similar. Peroperative urine samples revealed bacteriuria in one and two patients for the first and second groups, respectively. Fever of >38°C (P=0.52) developed in four (11.1%) patients in the first and six (16.2%) patients in the second group. Positive stone cultures developed in eight patients; of those, three (8.3%) were in the first and five (13.5%) were in the second group (P=0.47). The urine sent for culture on the nephrostomy catheter withdrawal day had positive results in three and two patients for the first and second groups (P=0.54). CONCLUSION Both antibiotic prophylaxis methods were similar in terms of preventing septic complications. Therefore, we think that a single-dose antibiotic prophylaxis protocol may be safely recommended to patients undergoing PCNL.


Clinical Genitourinary Cancer | 2012

Prevalence and predictors of benign lesions in renal masses smaller than 7 cm presumed to be renal cell carcinoma.

Bulent Akdogan; Ahmet Gudeloglu; Kubilay Inci; Levent Mert Gunay; Artan Koni; Haluk Ozen

UNLABELLED The present study was designed to determine the incidence and predictive factors of benign renal lesions in 450 patients who underwent surgical removal of solitary renal masses <7 cm in diameter. Of the 450 renal masses, 88 (19.9%) were benign lesions. Female sex, nephron-sparing surgery, surgery between 1990 and 1996, cystic components on imaging, and small tumors (<4 cm) were independently associated with benign pathology. PURPOSE To determine the association between preoperative parameters with final benign pathology in patients who underwent surgical removal of solitary renal masses <7 cm in diameter. MATERIALS AND METHODS A database of 450 patients without metastatic disease who underwent radical nephrectomy or nephron-sparing surgery (NSS) for removal of renal masses <7 cm between January 1990 and December 2009 was reviewed. Age, sex, symptoms, year and type of surgery, solid or cystic appearance, and tumor size were analyzed as presumed predictors of benign pathology. Multivariate analysis was performed to identify parameters associated with benign pathology. RESULTS In all, 88 (19.9%) of the tumors were benign, including 39 (8.7%) oncocytomas and 22 (4.9%) angiomyolipomas. The benign lesion rate for tumors ≤2, 2.1-4, and 4.1-7 cm was 30.3%, 27.1%, and 12.5%, respectively (2P < .001). For the periods of 1990-1996, 1997-2003, and 2004-2009, the frequency of benign tumors was 25%, 17.3%, and 18.4% (2P = .271), the incidental tumor rate was 48.1%, 60.4%, and 63.8% (2P = .027), mean tumor size was 5, 4.6, and 4.1 cm (2P < .001), and the NSS rate was 28.8%, 43.2%, and 52.7% (2P < .001), respectively. Logistic regression analysis revealed that female sex, NSS, surgery between 1990 and 1996, cystic components on imaging, and small tumors (<4 cm) based on radiologic examination were independently associated with benign pathology (odds ratio [OR] = 3.26, 2.56, 2.43, 2.41, and 1.96, respectively). CONCLUSIONS The incidence of incidental and small tumors amenable to NSS increased over time. Female sex was the strongest predictor of benign pathology.


Urologic Oncology-seminars and Original Investigations | 2013

A prospective randomized multicenter study of Turkish Society of Urooncology comparing two different mechanical bowel preparation methods for radical cystectomy

Güven Aslan; Sümer Baltaci; Bulent Akdogan; Uğur Kuyumcuoğlu; Mustafa Kaplan; Cag Cal; Oztug Adsan; Kadir Türkölmez; Sinan Ekici; Gokhan Faydaci; Elnur Mammadov; Levent Türkeri; Haluk Ozen; Yaşar Bedük

OBJECTIVE To investigate the outcomes and complication rates of urinary diversion using mechanical bowel preparation (BP) with 3 day conventional and limited BP method through a standard perioperative care plan. MATERIALS AND METHODS This study was designed as a prospective randomized multicenter trial. All patients were randomized to 2 groups. Patients in standard 3-day BP protocol received diet restriction, oral antibiotics to bowel flora, oral laxatives, and saline enemas over a 3-day period, whereas limited the BP arm received liberal use of liquid diet, sodium phosphate laxative, and self administered enema the day before surgery. All patients received same perioperative treatment protocol. The endpoints for the assessment of outcome were anastomotic leakage, wound infection, wound dehiscence, intraperitoneal abscess, peritonitis, sepsis, ileus, reoperation, and mortality. Bowel function recovery, including time to first bowel movement, time to first oral intake, time to regular oral intake, and length of hospital stay were also assessed. RESULTS Fifty-six patients in 3-day BP and 56 in limited BP arm were evaluable for the study end points. Postoperatively, 1 patient in limited BP and 2 patients in 3-day BP arm died. There was no statistical difference in any of the variables assessed throughout the study, however, a favorable return of bowel function and time to discharge as well as lower complication rate were observed in limited BP group. CONCLUSIONS Regarding all endpoints, including septic and nonseptic complications, current clinical research offers no evidence to show any advantage of 3-day BP over limited BP.


Journal of Pediatric Urology | 2006

Significance of age-specific creatinine levels at presentation in posterior urethral valve patients

Bulent Akdogan; Hasan Serkan Dogan; Selcuk Keskin; Berk Burgu; Serdar Tekgül

OBJECTIVE Determination of prognostic factors is of great importance in decision making on therapies and informing parents about the probable outcome of disease. The present study aims to evaluate and assess the prognostic factors in posterior urethral valve (PUV) patients. MATERIALS AND METHODS The data of 68 patients treated between 1996 and 2004 were evaluated retrospectively. The mean age at diagnosis was 36.4 months. The serum creatinine levels were standardized using the age-specific creatinine reference (ASCR) levels. The age at diagnosis, clinical presentation, initial serum creatinine, method of treatment, presence of vesicoureteral reflux (VUR) and hydroureteronephrosis (HUN), all of which may effect the prognosis, were evaluated. RESULTS The analysis revealed that, of the 36 patients whose initial serum creatinine levels were within ASCR, only one (2.8%) had a final serum creatinine higher than ASCR values. In contrast, of the 32 patients whose initial serum creatinine levels were not within ASCR, 19 (59.4%) had final serum creatinine levels higher than ASCR (P<0.001). The distribution of final serum creatinine according to treatment method, presence of UTI before treatment and age at diagnosis was not statistically significant; however, the difference in distribution for initial serum creatinine (P<0.001), mode of clinical presentation (0.016), presence of HUN (0.019) and state of VUR (0.037) before treatment was statistically significant. CONCLUSION Final outcome with regard to renal function in PUV patients is affected by bilateral VUR and most significantly by serum creatinine levels higher than ASCR.


Urologic Oncology-seminars and Original Investigations | 2010

Renal cell carcinoma with inferior vena cava thrombus: The Hacettepe experience

Sertac Yazici; Kubilay Inci; Cenk Yucel Bilen; Ahmet Gudeloglu; Bulent Akdogan; Dilek Ertoy; Volkan Kaynaroğlu; Metin Demircin; Haluk Ozen

OBJECTIVES We evaluated the clinical outcome and factors affecting survival in patients with renal cell carcinoma (RCC) and tumor thrombus involving inferior vena cava (IVC). METHODS Between 1990 and 2007, 28 patients with RCC and tumor thrombus extending into IVC underwent radical nephrectomy and thrombectomy. Patient data were reviewed retrospectively to evaluate the demographics, clinical presentation, surgical approach, pathological features, clinical outcomes, and survival. RESULTS Twenty-eight patients with a mean age of 52.7 years were operated. Thrombus level was infrahepatic in 15 patients (54%), intrahepatic in 3 patients (10%), suprahepatic in 3 patients (10%), supradiaphragmatic in 2 patients (8%), and intracardiac in 5 patients (18%). All patients with intracardiac thrombi underwent cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). The mean tumor size was 98.21 mm. Four patients had distant metastases and 3 patients had lymph node involvement. Pathological examination revealed RCC of clear cell type in 26 patients, papillary in 1 and chromophobe in 1 patient. At a mean follow-up of 36.4 months, 16 patients were still alive while 8 patients died due to disease progression and 2 patients died of other causes. Two patients died of pulmonary emboli in the early postoperative period. Lymph node involvement, distant metastases, hypercalcemia, and sarcomatoid component were found to be factors affecting overall survival significantly. Level of tumor thrombus and Fuhrman grade did not affect survival. CONCLUSIONS Radical nephrectomy and tumor thrombectomy is currently known to be the most effective method in patients with RCC and tumor thrombus extending into IVC. Factors affecting survival are the ones related to tumor biology. Tumor thrombus level does not affect the prognosis.


Urologia Internationalis | 2012

Prediction of Response to Androgen Deprivation Therapy and Castration Resistance in Primary Metastatic Prostate Cancer

Rauf Taner Divrik; Levent Türkeri; Ali Feyzullah Şahin; Bulent Akdogan; Ferhat Ates; Cag Cal; Sümer Baltaci

Purpose: We tried to establish the predictive factors influencing the initial response, as well as its duration, and time to castration resistance (CR) for primary advanced prostate cancer (PC) with bone metastasis. Methods: We evaluated all patients initially receiving androgen deprivation therapy (ADT) for primary advanced PC with bone metastasis. A total of 982 patients with complete medical records available for analysis from 18 centers were included in this study. Age, initial PSA, Gleason score (GS) and extent of bone involvement (EBI) were recorded in a database. Results: Among all the patients, 896 (91.2%) responded to ADT initially. Pretreatment PSA and EBI were significant predictors in the multivariate model. Among the 659 patients who progressed into a CR state, the mean duration of response was 22.4 months. There was a significant correlation between the CR state and nadir PSA (nPSA) level and time to nPSA. Pretreatment PSA, EBI, GS, highest tumor volume in biopsy cores (%), number of positive biopsy cores, percent positive biopsy cores and time to nPSA were proven to be significant to predict a nPSA. Pretreatment PSA, GS and EBI were statistically significant predictors of PSA normalization in multivariate analysis. The limitation of the study depends on the retrospective design and a model was developed for low standardization as a result of using multicenter data. The patients enrolled in this study were from a relatively long period of time (1989–2008). Conclusions: The results of this study indicate that it is possible to predict the initial response to ADT by pretreatment PSA levels and EBI, while the duration of response can be reflected by a multitude of clinical factors including nPSA, TTnPSA, percent positive cores, biopsy GS and EBI.


Urologia Internationalis | 2007

Does Age Affect the Prognosis of Patients with Testicular Germ Cell Tumor

Kubilay Inci; Hasan Serkan Dogan; Bulent Akdogan; Ali Ergen; Celik Tasar; Haluk Ozen

Introduction: In this study, the effect of age on the prognosis of testicular germ cell tumors in patients over 40 was investigated. Materials and Methods: Ninety-three patients with testicular germ cell tumor who were 40 years old and over were identified in our germ cell tumor database. Patients were grouped according to their age with those between 40 and 44, 45 and 49 and 50 and over constituting groups I, II and III, respectively. Results: Only 15% of the patients of group III had localized disease (p = 0.002). Group III patients had a significantly lower response rate to initial chemotherapy and a higher disease progression rate during therapy (complete response rate: 33.3%, progression rate: 44.4%, p = 0.035). The multivariate analysis revealed that advanced stage was the only independent prognostic factor for survival (p = 0.0011). Conclusion: Testicular germ cell tumor patients over 50 years old presented with a more advanced stage and had higher disease progression and disease mortality rates.

Collaboration


Dive into the Bulent Akdogan's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Alessandro Volpe

University of Eastern Piedmont

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Marco Roscigno

Vita-Salute San Raffaele University

View shared research outputs
Top Co-Authors

Avatar

Tobias Klatte

Medical University of Vienna

View shared research outputs
Top Co-Authors

Avatar

Umberto Capitanio

Vita-Salute San Raffaele University

View shared research outputs
Top Co-Authors

Avatar

Oscar Rodriguez-Faba

Autonomous University of Barcelona

View shared research outputs
Top Co-Authors

Avatar

R. Campi

University of Florence

View shared research outputs
Top Co-Authors

Avatar

Hans Langenhuijsen

Radboud University Nijmegen Medical Centre

View shared research outputs
Researchain Logo
Decentralizing Knowledge