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Featured researches published by Oktay Akca.


European Urology | 2016

Five-year Oncologic Outcomes After Transperitoneal Robotic Partial Nephrectomy for Renal Cell Carcinoma

Hiury S. Andrade; Homayoun Zargar; Peter A. Caputo; Oktay Akca; Onder Kara; Daniel Ramirez; Georges-Pascal Haber; Robert J. Stein; Jihad H. Kaouk

BACKGROUND Robotic partial nephrectomy (RPN) is established as a minimally invasive nephron-sparing technique with excellent perioperative and intermediate oncologic outcomes. However, long-term oncologic outcomes have not been reported to date. OBJECTIVE To report long-term oncologic outcomes of RPN. DESIGN, SETTING, AND PARTICIPANTS Consecutive patients undergoing RPN from June 2006 to March 2010 were selected from our prospective RPN database. Patients with benign tumors, prior ipsilateral PN, or prior radical nephrectomy and those with follow-up of <1 mo were excluded. INTERVENTION Transperitoneal RPN. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS Demographic, perioperative, and postoperative data were analyzed. Overall survival (OS), cancer-free survival (CFS), and cancer-specific survival (CSS) were evaluated using Kaplan-Meier survival analysis. Univariate logistic regression analysis for overall mortality was performed to evaluate the odds ratio (OR) for variables of interest. RESULTS AND LIMITATIONS In total, 115 RPNs for RCC were performed in 110 patients. The mean age was 59.8±11.0 yr and the median age-adjusted Charlson comorbidity index (ACCI) was 4 (interquartile range [IQR] 3-5). The median tumor size was 2.6cm (IQR 2.0-3.7) and median RENAL score was 7 (IQR 6-9). Clear cell carcinoma was present in 67.8% of cases, and two cases (1.7%) had positive surgical margins. Glomerular filtration rate preservation was 87.8% (IQR 74.9-98.1), which translates to 19.1% chronic kidney disease upstaging. The median follow-up was 61.9 mo (IQR 50.9-71.4) and the 5-yr OS, CFS, and CSS were 91.1%, 97.8%, and 97.8%, respectively. On univariable logistic regression, ACCI was the only factor associated with a higher risk of overall mortality (OR 1.67, p=0.006). The retrospective design, the high surgical volume at our institution, and the potential selection bias with careful patient selection early in the RPN experience may limit the generalizability of our findings. CONCLUSIONS This is the first study confirming excellent long-term oncologic outcomes after RPN in a selected cohort of patients. PATIENT SUMMARY Robotic partial nephrectomy is a relatively recently developed treatment for renal cell carcinoma. This study confirms its safety and reports excellent long-term cancer control.


BJUI | 2015

Ipsilateral renal function preservation after robot-assisted partial nephrectomy (RAPN): an objective analysis using mercapto-acetyltriglycine (MAG3) renal scan data and volumetric assessment.

Homayoun Zargar; Oktay Akca; Riccardo Autorino; Luis Felipe Brandao; Humberto Laydner; Jayram Krishnan; Dinesh Samarasekera; Robert J. Stein; Jihad H. Kaouk

To objectively assess ipsilateral renal function (IRF) preservation and factors influencing it after robot‐assisted partial nephrectomy (RAPN).


The Journal of Urology | 2015

Laparoscopic Cryoablation for Renal Cell Carcinoma: 100-Month Oncologic Outcomes

Peter A. Caputo; Daniel Ramirez; Homayoun Zargar; Oktay Akca; Hiury S. Andrade; Charles O’Malley; Erick M. Remer; Jihad H. Kaouk

PURPOSE With the incidence of renal cell carcinoma on the rise treatment options for the small renal mass have broadened. Cryoablation is increasingly used as a therapeutic option for renal tumors in select cases. However, studies with long-term oncologic outcomes are sparse. We evaluated the long-term oncologic outcomes of laparoscopic renal mass cryoablation. MATERIALS AND METHODS We reviewed our laparoscopic cryoablation database for patients treated with laparoscopic cryoablation from October 1997 to February 2005. Patients with less than 3 months of followup were excluded from study. Patient and tumor characteristics, and perioperative outcomes, including complications, were recorded. Recurrence-free, cancer specific and overall survival was analyzed using Kaplan-Meier curves. RESULTS A total of 142 tumors in 138 consecutive patients were treated with laparoscopic cryoablation. Mean age of the cohort was 66.35 years. Of the patients 99 (71.7%) were male and 39 (28.3%) were female. Mean body mass index was 29.15 kg/m(2) and median ASA score was 3. A solitary kidney was present in 23 patients (16.2%). Mean tumor size on cross-sectional imaging was 2.4 cm. The mean preoperative and postoperative estimated glomerular filtration rate was 66.72 and 61.00 ml per minute, respectively. The postoperative estimated glomerular filtration rate was determined at a mean ± SD of 15.17 ± 10.99 months of followup. The median R.E.N.A.L. nephrometry score was 5. Of the 142 tumors 100 were diagnosed as renal cell carcinoma after histopathological examination of the biopsy specimen. At 3, 5 and 10 years in patients diagnosed with renal cell carcinoma estimated recurrence-free survival was 91.4%, 86.5% and 86.5%, estimated cancer specific survival was 96.8%, 96.8% and 92.6%, and estimated overall survival was 88.7%, 79.1% and 53.8%, respectively. Mean followup was 98.8 ± 54.2 months in those diagnosed with renal cell carcinoma. Mean time to recurrence was 2.3 years. The latest experienced recurrence was 4.4 years after laparoscopic cryoablation. There was a postoperative complication rate of 10.6% with a total of 15 complications. CONCLUSIONS Laparoscopic cryoablation achieves good long-term oncologic outcomes for localized small renal masses. It can safely be used in patients who cannot undergo or are unwilling to accept the risks of partial nephrectomy. Mean time to recurrence was 2.3 years and all recurrences developed within 4.4 years of initial treatment.


Urology | 2011

SWL in Lower Calyceal Calculi: Evaluation of the Treatment Results in Children and Adults

Cemal Göktaş; Oktay Akca; Rahim Horuz; Okan Gökhan; Selami Albayrak; Kemal Sarica

OBJECTIVE To evaluate the treatment parameters of shockwave lithotripsy (SWL) in lower calyceal calculi in adults and children in a comparative manner. MATERIAL AND METHODS Between 2006 and 2011, SWL was performed for lower calyceal calculi in 282 adults (mean age 48.5 years, range 28-64) and 54 children (mean age 48 months, range 5-141). The Wolf Piezolith 3000 lithotriptor has been used for SWL. Success rates, auxiliary procedures, additional interventions, and complications were evaluated in detail in a comparative manner. RESULTS Mean stone size was 7.7 mm (range 5-25) and 8.1 mm (range 5-23) in children and in adults, respectively. Mean SWL sessions were 1.5 (range 1-5) in children and 2.4 (range 1-6) in adults. Although 66.6% of children were stone-free after the first session, 28% of adult patients were stone-free after the first SWL session, showing a statistically significant difference (P = .0001). After the treatments, although a complete stone-free status was obtained in 85% of children, 31.5% of adults were stone-free at 3-month follow-up after SWL (P = .0001). Although no auxiliary procedures were needed in children, 8.2% of adults required them. Likewise, the percentage of additional procedures were higher in adults than children (20.2%). CONCLUSION SWL for lower calyceal calculi has been found to be highly successful in pediatric patients. These results demonstrate that, irrespective of stone size, SWL should be the first treatment alternative in the management of lower calyx stones in children.


BJUI | 2015

Laparoendoscopic single-site (LESS) vs laparoscopic living-donor nephrectomy: a systematic review and meta-analysis

Riccardo Autorino; Luis Felipe Brandao; Bashir R. Sankari; Homayoun Zargar; Humberto Laydner; Oktay Akca; Marco De Sio; Vincenzo Mirone; Shih-Chieh J. Chueh; Jihad H. Kaouk

The aim of this study was to provide a systematic review and meta‐analysis of reports comparing laparoendoscopic single‐site (LESS) living‐donor nephrectomy (LDN) vs standard laparoscopic LDN (LLDN). A systematic review of the literature was performed in September 2013 using PubMed, Scopus, Ovid and The Cochrane library databases. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta‐analyses criteria. Weighted mean differences (WMDs) were used to measure continuous variables and odds ratios (ORs) to measure categorical ones. Nine publications meeting eligibility criteria were identified, including 461 LESS LDN and 1006 LLDN cases. There were more left‐side cases in the LESS LDN group (96.5% vs 88.6%, P < 0.001). Meta‐analysis of extractable data showed that LLDN had a shorter operative time (WMD 15.06 min, 95% confidence interval [CI] 4.9–25.1; P = 0.003), without a significant difference in warm ischaemia time (WMD 0.41 min, 95% CI –0.02 to 0.84; P = 0.06). Estimated blood loss was lower for LESS LDN (WMD −22.09 mL, 95% CI –29.5 to –14.6; P < 0.001); however, this difference was not clinically significant. There was a greater likelihood of conversion for LESS LDN (OR 13.21, 95% CI 4.65–37.53; P < 0.001). Hospital stay was similar (WMD –0.11 days, 95% CI –0.33 to 0.12; P = 0.35), as well as the visual analogue pain score at discharge (WMD –0.31, 95% CI –0.96 to 0.35; P = 0.36), but the analgesic requirement was lower for LESS LDN (WMD –2.58 mg, 95% CI –5.01 to –0.15; P = 0.04). Moreover, there was no difference in the postoperative complication rate (OR 1.00, 95% CI 0.65–1.54; P = 0.99). Renal function of the recipient, as based on creatinine levels at 1 month, showed similar outcomes between groups (WMD 0.10 mg/dL, –0.09 to 0.29; P = 0.29). In conclusion, LESS LDN represents an emerging option for living kidney donation. This procedure offers comparable surgical and early functional outcomes to the conventional LLDN, with a lower analgesic requirement. However, it is more technically challenging than LLDN, as shown by a greater likelihood of conversion. The role of LESS LDN remains to be defined.


The Journal of Urology | 2014

30-Day Hospital Readmission after Robotic Partial Nephrectomy—Are We Prepared for Medicare Readmission Reduction Program?

Luis Felipe Brandao; Homayoun Zargar; Humberto Laydner; Oktay Akca; Riccardo Autorino; Oliver Ko; Dinesh Samarasekera; Jianbo Li; John Rabets; Jayram Krishnan; Georges-Pascal Haber; Jihad H. Kaouk; Robert J. Stein

PURPOSE After CMS introduced the concept of the Hospital Readmissions Reduction Program, hospitals and health care centers became financially penalized for exceeding specific readmission rates. MATERIALS AND METHODS We retrospectively reviewed our institutional review board approved database of patients undergoing robotic partial nephrectomy at our institution and included in our analysis patients who were readmitted to any hospital as an inpatient stay within 30 days from discharge home after robotic partial nephrectomy. RESULTS From March 2006 to March 2013 a total of 627 patients underwent robotic partial nephrectomy at our center and 28 (4.46%) were readmitted within 30 days of surgery. Postoperative bleeding was responsible for 8 (28.5%) readmissions. Pulmonary embolism was reported in 3 cases and retroperitoneal abscess was diagnosed in 2. Urinary leak requiring surgical intervention developed in 2 patients, pneumonia was diagnosed in 2 and 2 patients were readmitted for chest pain. Overall 9 (32.1%) patients presented with major complications requiring intervention. On multivariable analysis Charlson comorbidity index score was the only factor significantly associated with a higher 30-day readmission rate (p = 0.03). If the Charlson score was 5 or greater the chance of hospital readmission would be 2.7 times higher. CONCLUSIONS Increased comorbidity, specifically a Charlson score of 5 or greater, was the only significant predictor of a higher incidence of 30-day readmission. This information can be useful in counseling patients regarding robotic partial nephrectomy and in determining baseline rates if CMS expands the number of conditions they evaluate for excess 30-day readmissions.


European Urology | 2014

Robot-assisted Laparoscopic Adrenalectomy: Step-by-Step Technique and Comparative Outcomes

Luis Felipe Brandao; Riccardo Autorino; Homayoun Zargar; Jayram Krishnan; Humberto Laydner; Oktay Akca; Maria Carmen Mir; Dinesh Samarasekera; Robert J. Stein; Jihad H. Kaouk

BACKGROUND Recent evidence supports the use of robotic surgery for the minimally invasive surgical management of adrenal masses. OBJECTIVE To describe a contemporary step-by-step technique of robotic adrenalectomy (RA), to provide tips and tricks to help ensure a safe and effective implementation of the procedure, and to compare its outcomes with those of laparoscopic adrenalectomy (LA). DESIGN, SETTING, AND PARTICIPANTS We retrospectively reviewed the medical charts of consecutive patients who underwent RA performed by a single surgeon between April 2010 and October 2013. LA cases performed by the same surgeon between January 2004 and May 2010 were considered the control group. SURGICAL PROCEDURE The main steps of our current surgical technique for RA are described in this video tutorial: patient positioning, port placement, and robot docking; exposure of the adrenal gland; identification and control of the adrenal vein; circumferential dissection of the adrenal gland; and specimen retrieval and closure. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Demographic parameters and main surgical outcomes were assessed. RESULTS AND LIMITATIONS A total of 76 cases (RA: 30; LA: 46) were included in the analysis. Median tumor size on computed tomography (CT) was significantly larger in the LA group (3cm [interquartile range (IQR): 3] vs 4cm [IQR: 3]; p=0.002). A significantly lower median estimated blood loss was recorded for the robotic group (50ml [IQR: 50] vs 100ml [IQR: 288]; p=0.02). The RA group presented five minor complications (16.7%) and one major (Clavien 3b) complication (3.3%), whereas four minor complications (8.7%) and one major (Clavien 3b) complication (2.3%) were observed in the LA group. No significant difference was noted between groups in terms of malignant histology (p=0.66) and positive margin rate (p=0.60). Distribution of pheochromocytomas in the LA group was significantly higher than in the RA group (43.5% vs 16.7%; p=0.02). CONCLUSIONS The standardization of each surgical step optimizes the RA procedure. The robotic approach can be applied for a wide range of adrenal indications, recapitulating the safety and effectiveness of open surgery and potentially improving the outcomes of standard laparoscopy. PATIENT SUMMARY In this report we detail our surgical technique for robotic removal of adrenal masses. This procedure has been standardized and can be offered to patients, with excellent outcomes.


European Urology | 2015

Robotic Surgery Revives Radical Perineal Prostatectomy.

Oktay Akca; Homayoun Zargar; Jihad H. Kaouk

Radical perineal prostatectomy (RPP) was first described by Young at the beginning of 20th century [1]. With refinements of the anatomic retropubic approach in the early 1980s, the perineal approach became less favored, as most urologists preferred the familiar and less complex anatomy of the retropubic approach. However, technical modifications to allow for cavernous nerve sparing and pelvic lymph node dissection have allowed RPP to remain an alternative technique for surgeons who are familiar with this approach [2]. Despite comparable oncologic and functional outcomes [3], technical challenges (eg, deep and narrow operative field, ergonomic issues affecting the surgeon) have encumbered wider RPP use [4]. To overcome these challenges, we conceived and developed a robotic approach to RPP in a cadaveric model [5]. We report the clinical feasibility of this approach in two patients with localized prostate cancer for whom alternative transabdominal approaches were considered to be technically challenging. One patient had a surgical history of abdominoperineal resection of the rectum for ulcerative colitis and bilateral inguinal mesh herniorrhaphy. The other patient had a history of aborted robotic assisted laparoscopic radical prostatectomy due to abdominal adhesions and morbid obesity 3 mo earlier. For robotic [1_TD


Journal of Endourology | 2014

Perineal robot-assisted laparoscopic radical prostatectomy: feasibility study in the cadaver model.

Humberto Laydner; Oktay Akca; Riccardo Autorino; R. Eyraud; Homayoun Zargar; Luis Felipe Brandao; Ali Khalifeh; Kamol Panumatrassamee; Jean-Alexandre Long; Wahib Isac; Robert J. Stein; Jihad H. Kaouk

DIFF]RPP, the patient is placed in an exaggerated lithotomy position with a 158 Trendelenburg tilt. The perineal incision is made at the apex of a semicircular line drawn between the ischial tuberosities. With normal perineal anatomy after incision of the central tendon, using Belt’s approach, the rectourethral muscle is exposed [6]. A single port is then placed, and the robot is docked (Fig. 1). E U R O P E A N U R O L O G Y 6 8 ( 2 0 1 5 ) 3 4 0 – 3 4 3


Urology | 2014

Robot-assisted partial nephrectomy for ≥ 7 cm renal masses: a comparative outcome analysis.

Luis Felipe Brandao; Homayoun Zargar; Riccardo Autorino; Oktay Akca; Humberto Laydner; Dinesh Samarasekera; Jayram Krishnan; Georges-Pascal Haber; Robert J. Stein; Jihad H. Kaouk

PURPOSE To evaluate the feasibility of perineal robot-assisted laparoscopic radical prostatectomy (P-RALP) in the cadaver model. METHODS The prostate was assessed by ultrasonography and cystoscopy in the lithotomy position. After incision and subcutaneous dissection, a single-port device was placed and the robot was docked. The rectourethralis muscle was divided and the levator ani fibers were split. The Denonvilliers fascia was incised and the posterior prostate and seminal vesicles were dissected. The apex was dissected and the urethra was transected. The anterior and lateral planes were dissected and the prostate pedicles were clipped. The prostate was freed from the bladder neck and the vesicourethral anastomosis was performed. The robot was undocked and the wound was sutured in layers. Cystoscopy confirmed integrity of the anastomosis. The specimen was sent for histopathology examination. RESULTS Nerve-sparing P-RALP was successfully completed in three cadavers. Median time for setting was 23 minutes. Time for posterior dissection was 15 minutes. Dissection of the apex and section of the urethra took 9 minutes. Time for anterolateral dissection was 14 minutes. Time for bladder neck dissection was 7 minutes. Vesicourethral anastomosis took 8 minutes. Total operative time was 89 minutes. The prostate capsule was grossly intact and histopathology examination was negative for prostatic tissue in all distal urethral sections and in two of three bladder neck sections. CONCLUSIONS P-RALP is feasible in the cadaver. Future studies should evaluate the feasibility of lymph node dissection through the same incision, clinical feasibility, and prospective comparisons with standard techniques.

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Riccardo Autorino

Virginia Commonwealth University

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Daniel Ramirez

University of Texas Southwestern Medical Center

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