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Featured researches published by Ran Katz.


Urology | 2003

Radical retropubic versus laparoscopic prostatectomy: a prospective comparison of functional outcome

Aristotelis G. Anastasiadis; Laurent Salomon; Ran Katz; Andras Hoznek; Dominique Chopin; C.C. Abbou

OBJECTIVES To evaluate and compare prospectively the functional results (urinary continence and erectile function) after retropubic and laparoscopic radical prostatectomy. METHODS From 1998 to 2001, 300 patients underwent radical prostatectomy, 70 by the retropubic and 230 by the laparoscopic approach. All of them completed a confidential, self-administered questionnaire regarding urinary continence and erectile function before and 1, 3, 6, and 12 months after surgery. The results were analyzed separately for day and nighttime urinary continence and by neurovascular bundle status and age for erectile function. RESULTS No differences were found between the two groups except for the duration of bladder catheterization (7.8 days for the retropubic and 5.8 for the laparoscopic approach, P = 0.0006). Before surgery, 296 patients (98.7%) were continent and 290 (96.6%) were potent. One year after surgery, diurnal urinary continence increased progressively to 66.7% and 71.6% (P >0.05), nocturnal continence to 66.7% and 87.1% (P = 0.008), and potency rates to 30% and 41% (P >0.05) for the retropubic and the laparoscopic approaches, respectively. After preservation of one and two neurovascular bundles, the potency rate increased to 27% and 46% and 44% and 53% for the retropubic and laparoscopic approaches, respectively (P >0.05). For patients younger than 60 years old with bilateral neurovascular bundle preservation, the potency rates were 72% and 81% (P >0.05). CONCLUSIONS The two approaches showed similar outcomes regarding continence and erectile function 1 year after surgery. However, the recovery of nocturnal continence seemed to occur earlier after the laparoscopic approach. It is necessary to conduct additional studies to determine the potential benefits of the laparoscopic approach regarding nocturnal continence.


European Urology | 2002

Urinary continence and erectile function: A prospective evaluation of functional results after radical laparoscopic prostatectomy

L. Salomon; Aristotelis G. Anastasiadis; Ran Katz; Alexandre de la Taille; Fabien Saint; D. Vordos; Anthony Cicco; Andras Hoznek; Dominique Chopin; C.C. Abbou

OBJECTIVES To evaluate prospectively functional results (urinary continence and erectile function) after laparoscopic radical prostatectomy. METHODS From 1998 to 2001, 235 patients underwent laparoscopic radical prostatectomy for localized prostate cancer. All of them completed a confidential, self-administered questionnaire regarding urinary continence and erectile function before, and 1, 3, 6, and 12 months after surgery. Results were analyzed separately for day and night for urinary continence and status of neurovascular bundles as well as age for erectile function. RESULTS To date, 100 consecutive patients have completed all questionnaires. Diurnal and nocturnal urinary continence have increased to 90% and 97% one year after surgery. Overall, 49.3% of the 77 patients, who were potent preoperatively, and did not receive any form of adjuvant therapy, had erections sufficient for intercourse one year after surgery. Potency rates were 38.4%, 53.8% and 58.8% after no, unilateral, and bilateral nerve bundle preservation, respectively. For younger patients (<60 years) with unilateral and bilateral neurovascular bundle preservation, potency rates were 75% and 83.3%, respectively. CONCLUSION One year after laparoscopic radical prostatectomy, urinary continence rate is 90% during the day and 97% during the night. Overall potency rates after bilateral preservation of neurovascular bundles are 58.8% and 83.8% for the subgroup of younger patients (<60 years).


Urology | 2003

Assessment of surgical technique and perioperative morbidity associated with extraperitoneal versus transperitoneal laparoscopic radical prostatectomy

Andrs Hoznek; Patrick Antiphon; Tomasz Borkowski; Matthew T. Gettman; Ran Katz; Laurent Salomon; Safwat Zaki; Alexandre de la Taille; C.lment-Claude Abbou

OBJECTIVES To compare the perioperative morbidity and surgical technique of the two main variants of laparoscopic radical prostatectomy: the more often used transperitoneal approach with primary dissection of the plane posterior to the seminal vesicles (TP-LRP) and a purely extraperitoneal approach (EP-LRP). METHODS Our initial 20 consecutive patients who underwent EP-LRP and the last 20 consecutive patients who underwent TP-LRP were included in this retrospective study. The two groups were well matched for age, American Society of Anesthesiologists score, body mass index, prostate-specific antigen level, and Gleason score. The mean time for completion of the individual laparoscopic steps was assessed for both approaches. RESULTS With EP-LRP, the mean operative time was shorter (169.6 minutes versus 224.2 minutes, P <0.001) and patients resumed a full diet earlier (mean 1.6 days versus 2.6 days, P = 0.002). The mean total dose and duration of morphine administration were higher in the TP-LRP group, but the difference was not statistically significant (6.0 mg versus 12.8 mg and 0.5 day versus 0.9 day, respectively). The catheter time was nearly identical in the two groups (mean 5.3 days with TP-LRP and 4.2 days with EP-LRP). The incidence of positive margins was not affected by the surgical approach. CONCLUSIONS These preliminary results suggest that the initial posterior dissection associated with TP-LRP is less efficacious than direct access of the prevesical space during EP-LRP. Measures of perioperative morbidity were at least equivalent, if not superior, for the EP-LRP technique. These findings, together with the significant decrease in operative time with EP-LRP, appear sufficiently important to abandon the transperitoneal technique.


Urology | 2003

Location of positive surgical margins after retropubic, perineal, and laparoscopic radical prostatectomy for organ-confined prostate cancer

Laurent Salomon; Aristotelis G. Anastasiadis; Olivier Levrel; Ran Katz; Fabien Saint; Alexandre de la Taille; Antony Cicco; Dimitri Vordos; Andras Hoznek; Dominique Chopin; C.C. Abbou

OBJECTIVES To evaluate and compare the location of positive surgical margins after retropubic, perineal, and laparoscopic radical prostatectomy for organ-confined prostate cancer (pT2). METHODS From 1988 to 2001, 538 patients underwent radical prostatectomy for clinically localized prostate cancer. Patient age at surgery, clinical stage, preoperative prostate-specific antigen, and Gleason score of positive biopsies were noted. Postoperatively, specimen weight, final Gleason score, and capsular, seminal vesicle, and lymph node status, as well as tumor volume, were studied. The incidence and location of positive margins and the pathologic stage were noted according to the surgical approach. RESULTS A total of 371 patients (69.5%) had organ-confined tumors. Of the 371 patients, 116 underwent the retropubic, 86 the perineal, and 169 the laparoscopic approach, and positive surgical margins were noted in 22 (18.9%), 12 (13.9%), and 32 (18.9%) patients, respectively. Positive surgical margins were reported in 72 specimen locations, 32 (44.4%) at the apex, 17 (23.6%) at the bladder neck, and 29 (31.9%) posterolaterally. The distribution for the retropubic, perineal, and laparoscopic approaches was apex in 50%, 33.3%, and 44.4%, bladder neck in 29.1%, 41.7%, and 13.9%, and posterolaterally in 20.8%, 25%, and 41.6%, respectively. CONCLUSIONS In our series, each approach had a specific high-risk location of positive margins: the apex for the retropubic, the bladder neck for the perineal, and posterolaterally for the laparoscopic approach. Improvements in the surgical techniques should take these specific locations under consideration to decrease the incidence of positive surgical margins.


The Journal of Urology | 2002

Patient reported sexual function following laparoscopic radical prostatectomy.

Ran Katz; Laurent Salomon; Andras Hoznek; Alexandre de la Taille; D. Vordos; Antony Cicco; Dominique Chopin; Clement Claude Abbou

PURPOSE We evaluated the sexual function of patients who underwent laparoscopic radical prostatectomy. We assessed the effect of unilateral or bilateral preservation of the neurovascular bundle on the ability to achieve erections and have sexual intercourse postoperatively. MATERIAL AND METHODS Between May 1998 and September 2001, 232 men underwent laparoscopic radical prostatectomy for localized prostate cancer at our institution. Sexual function questionnaires were given to the patients preoperatively. The study included 143 patients who were potent preoperatively. After the procedure the surgeon noted whether he performed unilateral, bilateral or no nerve sparing. Sexual function questionnaires were collected at 1, 3, 6 and 12 months after surgery. RESULTS Of the 143 patients, 100, 80, 48 and 26 responded to the questionnaire at 1, 3, 6 and 12 months respectively. Of the nonnerve sparing group 11.7%, 11.1%, 16.6% and 30%, of the unilateral nerve sparing group 20%, 35%, 41.6% and 50% and of the bilateral nerve sparing group 32.5%, 41.1%, 29.1% and 87.5% respectively reported spontaneous erections 1, 3, 6 and 12 months after surgery, respectively. The overall incidence of positive lateral surgical margins in pT2 cases treated with a nerve sparing procedure was 8.4%. CONCLUSIONS The overall rate of patients who had erections preoperatively and maintained erections after surgery (53.8%) is comparable to the results for open surgery. Patients with bilateral preservation did better than those with unilateral preservation. Our preliminary results show a promising rate of potency at 1 year after laparoscopic radical prostatectomy.


Urology | 2003

Operative management of rectal injuries during laparoscopic radical prostatectomy.

Ran Katz; Tomasz Borkowski; Andras Hoznek; Laurent Salomon; Alexandre de la Taille; Clement Claude Abbou

OBJECTIVES To present our experience in the management of rectal injuries during laparoscopic radical prostatectomy. METHODS All patients underwent bowel preparation and received perioperative antibiotics. If rectal injury was suspected, digital rectal examination was performed, aided by bubbling air into the rectum if required. When the diagnosis was confirmed, the hole was closed in two layers of absorbable sutures. A fat flap was developed from the omentum (in the transperitoneal approach) or the perirectal fat (in the extraperitoneal approach) and placed on the suture line. Anal dilation was performed. After surgery, broad-spectrum antibiotics and a low-residue diet were prescribed. RESULTS Of 300 patients who underwent surgery between May 1998 and June 2002, 6 (2%) had a rectal injury. The first patient had received neoadjuvant hormonal therapy. Five cases were in the transperitoneal approach and were closed using omental fat and 1 was in the extraperitoneal approach with a perirectal fat flap. The first patient presented with a rectourethral fistula and was treated with catheterization for 1 month and a diverting colostomy. The others were detected intraoperatively and were treated laparoscopically. In the second patient, a diverting colostomy was performed at the end of surgery using a separate incision. Patients resumed oral intake within 2 to 7 days and were discharged from the hospital between 6 and 18 days postoperatively. No wound infection was noted. CONCLUSIONS Rectal injuries during laparoscopic radical prostatectomy can be identified and managed intraoperatively without requiring conversion. Double-layered closure reinforced by a fat flap resulted in an uneventful recovery.


Urologia Internationalis | 2003

Cadaveric versus Porcine Models in Urological Laparoscopic Training

Ran Katz; Andras Hoznek; Patrick Antiphon; Roland van Velthoven; Vincent Delmas; C.C. Abbou

Introduction: Laparoscopy performed on anesthetized pigs is an established training model. In this pilot study, we performed laparoscopy on cadavers as a training modality for urologists participating in a laparoscopic seminar. Materials and Methods: We compared data from two consecutive laparoscopy seminars performed at our institution. The first included a laparoscopy session performed on pigs. The second was in the same setup, yet laparoscopy was performed on fresh cadavers. We analyzed and compared the trainees’ perspectives regarding the 2 modalities using a 5-scale satisfaction questionnaire. Results: Seven trainees attended the cadaveric and 9 the porcine laparoscopy session. The two groups were similar in terms of age and previous laparoscopic and urological experience. The general satisfaction of the two training modalities was high in the two groups, as well as their will for another session of the same kind. Yet the trainees ranked their understanding of the surgical anatomy, laparoscopic technique and use of instruments significantly higher in the cadaveric laparoscopy group (p values were 0.007, 0.006 and 0.032, respectively). Conclusions: Cadaveric laparoscopy may offer an ideal surgical environment allowing dissection and performance of complete procedures. In this pilot study, we conducted the first reported cadaveric laparoscopy training seminar in urology. The trainees preferred the cadaveric laparoscopy and found it superior to porcine laparoscopy. We believe that cadaveric laparoscopy is an important training tool, which may be added to the armamentarium of urological laparoscopy training courses.


The Journal of Urology | 2009

Extracorporeal shock wave lithotripsy in prepubertal children: 22-year experience at a single institution with a single lithotriptor.

Ezekiel H. Landau; Ofer Z. Shenfeld; Dov Pode; Amos Shapiro; Shimon Meretyk; Giora Katz; Ran Katz; Mordechai Duvdevani; Benjamin Hardak; Helio Cipele; Guy Hidas; Vladimir Yutkin; Ofer N. Gofrit

PURPOSE The sophistication of percutaneous nephrolithotomy and ureteroscopy challenges the efficacy of ESWL for urolithiasis in prepubertal patients. We evaluated our long-term experience with ESWL in these patients and determined its efficiency. MATERIALS AND METHODS We retrospectively reviewed the charts of all prepubertal patients who underwent ESWL. We evaluated the need for tubing, the 3-month stone-free rate, the need for additional ESWL, and the effect of stone size and location, and cystinuria on the 3-month stone-free rate. RESULTS Between 1986 and 2008, 119 males and 97 females with a mean age of 6.6 years who had urolithiasis underwent ESWL using the Dornier HM3 lithotriptor. We treated 157 children with renal calculi with an average +/- SD diameter of 14.9 +/- 8.9 mm, of whom 66 (42%) required a tube in the urinary system. The 3-month stone-free rate was 80% and 31 patients (19.7%) needed an additional procedure. Stone location did not affect the stone-free rate but stone size did. We treated 59 patients for ureteral stones with an average stone length of 9.5 +/- 4.8 mm, of whom 41 (69%) required tube insertion. The 3-month stone-free rate was 78% and 13 patients (22%) needed an additional procedure. The 3-month stone-free rate did not depend on stone location or size. The rate was 37.5% in patients with cystinuria and 82.5% in all others (p <0.0001). Six patients (2.8%) had complications. CONCLUSIONS The 3-month stone-free rate after ESWL in prepubertal patients is 80% and 20% of patients require additional procedures. ESWL is most effective for kidney stones less than 11 mm. ESWL has inferior results for cystine stones compared to other calculi. Complications are rare.


Urologia Internationalis | 2006

Laparoscopic Radical Prostatectomy in Patients following Transurethral Resection of the Prostate

Ran Katz; Tomasz Borkowski; Andras Hoznek; Laurent Salomon; Matthew T. Gettman; Clement Claude Abbou

Objectives: Previous transurethral resection of the prostate (TURP) was reported to impose difficulties during open radical prostatectomy. We describe our experience in laparoscopic radical prostatectomy (LRP) following transurethral resection of the prostate. Patients and Methods: The series included 35 patients: 22 patients underwent transperitoneal LRP (tpLRP) and 13 underwent extraperitoneal LRP (epLRP). The minimal interval between TURP and laparoscopy was 3 months. Patients’ charts were reviewed for their preoperative characteristics, intraoperative difficulties and complications, and outcome. Results: Patients’ mean age was 67.5 ± 4.4 years. 12 patients were cT1a,b and 23 patients were cT1c/T2. Twenty-two patients underwent tpLRP and 13 underwent epLRP. No statistical difference was found between the preoperative characteristics and the pathological results of cT1a,b vs. T1c/cT2 patients, or tpLRP vs. epLRP patients. Thirty-three procedures were completed laparoscopically and 2 were converted to open surgery. Perioperative complications included two leaking anastomoses, prolonged lymph drainage in 1 case, atelectasis (n = 1) and duodenal ulcer (n = 1). Twelve positive margins were noted, half of them in pT2 tumors. The mean follow-up was 28.5 months. Twenty-five of 35 patients had more than 12 months of follow-up. Among them 19 patients were completely continent (76%) and 6 (24%), reported mild stress incontinence. Conclusions: Although LRP following TURP is sometimes more technically difficult, simple modifications in the operative strategy help facilitate surgery. LRP following TURP favorably compares to open radical prostatectomy after TURP and laparoscopy in non-TURP patients.


Urologic Oncology-seminars and Original Investigations | 2009

The natural history of bladder carcinoma in situ after initial response to bacillus Calmette-Gúerin immunotherapy

Ofer N. Gofrit; Dov Pode; Galina Pizov; Kevin C. Zorn; Ran Katz; Mordechi Duvdevani; Amos Shapiro

OBJECTIVES To explore patterns of recurrence, muscle invasion, and disease specific mortality in patients with bladder carcinoma in situ (CIS) who responded to an induction course with intravesical bacillus Calmette-Gúerin (BCG) immunotherapy. METHODS Between June 1985 and December 2003, 104 patients (mean age 67 years) were diagnosed with either pure (38 patients) or concomitant (66 patients) CIS. Patients who responded to one (92 patients) or two (12 patients) induction courses of intravesical BCG instillation were included in the study. Response was determined and monitored by routine periodic bladder biopsies. Outcome of patients and the effect of various prognostic parameters were assessed after a median follow-up of 75 months. RESULTS The 5- and 10-year recurrence-free survival rates were 63% and 54%, respectively. The 5- and 10-year muscle-invasive-free survival rates were 79% and 77%, and the 5- and 10-year disease-specific survival rates were 90.5 and 85.8%, respectively. Median time to recurrence, muscle invasion, and disease-specific mortality was 18, 19, and 40 months, respectively. Pure and concomitant CIS were associated with a similar outcome. The recurrence of nonmuscle-invasive tumor did not increase the risk for muscle invasion or mortality. CONCLUSIONS Pure and concomitant bladder CIS share similar biologic behavior. Muscle-invasive disease is expected in about 25% of the BCG responders followed for long time periods and disease-specific mortality in 15%. Tumor recurrence, whether nonmuscle-invasive or muscle-invasive, follows a similar time table suggesting that these are not sequential but parallel and independent processes.

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Dov Pode

Hebrew University of Jerusalem

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Ofer N. Gofrit

Hebrew University of Jerusalem

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Ezekiel H. Landau

Hebrew University of Jerusalem

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Amos Shapiro

Washington University in St. Louis

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Amos Shapiro

Washington University in St. Louis

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Mordechai Duvdevani

University of Western Ontario

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Kevin C. Zorn

Université de Montréal

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Vladimir Yutkin

Hebrew University of Jerusalem

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Mordechai Duvdevani

University of Western Ontario

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Ofer Z. Shenfeld

Hebrew University of Jerusalem

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