Experience with 750 consecutive laparoscopic donor nephrectomies--is it time to use a standardized classification of complications?

PURPOSE: Laparoscopic living donor nephrectomy offers patients the benefits of decreased morbidity and improved cosmesis, while maintaining equivalent graft outcomes and complication rates similar to those of open donor surgery. With expressed concern for donor safety, using a standardized complication scale would allow combining data in a donor registry so potential donors could be adequately followed and counseled. We present the largest series to our knowledge of laparoscopic living donor nephrectomy by a single surgeon. MATERIALS AND METHODS: The institution's initial 750 laparoscopic living donor nephrectomies were included in the study, and a retrospective and prospective chart and database analysis was performed. RESULTS: Mean donor age was 40.5 years and average body mass index was 25.7 kg/m(2). There were 175 patients (23%) with 2 or more renal arteries while 161 (21.5%) had early arterial bifurcations. There were 3 open conversions (0.4%) and the overall complication rate was 5.46%. Median hospital stay was 1 day and the readmission rate was 1.2%. There were 5 reoperations (0.67%), none of which was for the control of bleeding. No patients required a blood transfusion and there were no mortalities. Using a modified Clavien classification of complications for living donor nephrectomy 65.8% were grade 1, 31.7% grade 2 (12.2% grade 2a, 14.6% grade 2b, 4.9% grade 2c) and 2.4% grade 3. There were no grade 4 complications. CONCLUSIONS: With appropriate patient selection and operative experience, laparoscopic living donor nephrectomy is a safe procedure associated with low morbidity. The use of a standardized complication system specific for this procedure is encouraged and could aid in counseling potential donors in the future.

Asynchronous, out-of-sequence, transcontinental chain kidney transplantation: a novel concept.

The organ donor shortage has been the most important hindrance in getting listed patients transplanted. Living kidney donors who are incompatible with their intended recipients are an untapped resource for expanding the donor pool through participation in transplant exchanges. Chain transplantation takes this concept further, with the potential to benefit even more recipients. We describe the first asynchronous, out of sequence transplant chain that was initiated by transcontinental shipment of an altruistic donor kidney 1 week after that recipient's incompatible donor had already donated his kidney to the next recipient in the chain. The altruistic donor kidney was transported from New York to Los Angeles and functioned immediately after transplantation. Our modified-sequence asynchronous transplant chain (MATCH) enabled eight recipients, at four different institutions, to benefit from the generosity of one altruistic donor and warrants further exploration as a promising step toward addressing the organ donor shortage.

Laparoscopic assisted live donor nephrectomy--a comparison with the open approach.

Live donor renal transplantation provides significant advantages when compared with cadaveric donor renal transplantation in terms of improved patient and graft survival, a lower incidence of delayed function, and a shorter waiting time. Yet despite these advantages, live donors continue to be an under utilized source of kidneys for transplantation. Disincentives to live donation include the length of hospitalization, postoperative pain, cosmetic concerns, and the prolonged convalescence associated with the donor operation. In many instances minimally invasive video-assisted techniques have proven more efficacious than standard open procedures in terms of patient discomfort, length of hospital stay, cost, and length of time until the patient can return to full activity. Laparoscopic live donor nephrectomies are being performed at our institution in an attempt to make live donation more attractive to the potential donor. The purpose of this study was to retrospectively review the results of laparoscopic live donor nephrectomy (LapNx) and to compare them with those obtained using the standard open approach (OpenNx). Ten consecutive LapNx were performed from February 1995 through April 1996. The control group consisted of the 20 consecutive OpenNx performed at the same institution from January 1991 through January 1995 immediately before the initiation of the LapNx program. Live donors were considered candidates for LapNx if they possessed at least one kidney with normal renal anatomy with single renal vessels and a single ureter. LapNx was safely performed in all cases. No patients required open conversion or blood transfusions. The allograft warm ischemic time for the laparoscopic cases was 4.2+/-1.3 min. All kidneys harvested laparoscopically produced urine on the table immediately upon revascularization. Presently nine of the ten recipients have functioning allografts. At three months posttransplant the calculated recipient creatinine clearances were 67.0+/-11.5 ml/min and 64.8+/-21.4 ml/min for the LapNx and OpenNx groups, respectively (P=NS). The LapNx donors had a significantly decreased estimated blood loss, shorter time until resumption of oral intake, decreased postoperative pain (in terms of decreased analgesic requirements), shorter hospitalization, and a shorter interval until the resumption of full activities (P<0.05 for all). In addition, the LapNx group donors returned to work sooner than the OpenNx group (3.9+/-1.6 wk vs. 6.4+/-3.1 wk, respectively) (P=0.024). Four individuals agreed to donate a kidney only after learning of the availability of the laparoscopic approach. We conclude that laparoscopic live donor nephrectomy is technically feasible. In addition, it may offer significant advantages over the standard open approach in terms of patient comfort and convenience. These advantages may make live donor renal transplantation more attractive to prospective donors. The potential decrease in hospitalization and convalescence may also prove to be financially advantageous. We believe that further careful study of this procedure is warranted.

Pseudotumor of the bladder: a late complication of inguinal herniorrhaphy.

Damage to the bladder during inguinal hernia repair is possible especially if the bladder or a bladder diverticulum is involved in the hernia sac. Unrecognized injury to the bladder can lead to late complications. We report a case of pseudotumor in a bladder diverticulum due to long-term retention of a misplaced suture. The literature on bladder injury after inguinal herniorrhaphy and on pseudotumor formation is briefly reviewed. It is important to be aware of a history of inguinal surgery and to obtain definitive histologic evidence of malignancy prior to making the diagnosis of bladder carcinoma. This will avoid unnecessary radical surgery, chemotherapy, or radiation therapy.

Laparoscopic radical prostatectomy: initial short-term experience.

OBJECTIVES: To determine the feasibility and efficacy of a laparoscopic approach to the radical retropubic prostatectomy (RRP). METHODS: A transperitoneal laparoscopic technique was developed to perform an RRP. Intra-abdominal access was obtained through five 10-mm trocars. After dissection of the prostate, the urethrovesical anastomosis was created via a transvesical approach. The prostate was removed by extending the umbilical incision. RESULTS: Between September 1991 and May 1995, nine laparoscopic RRPs were performed. The operative time averaged 9.4 hours. Only 1 of 9 patients had a positive surgical margin that involved the urethra. Six of 9 patients were completely continent postoperatively. Of the 4 patients who were potent preoperatively, 2 continued to have erections. There were three complications: cholecystitis, thrombophlebitis associated with a pulmonary embolism, and a small bowel hernia into a trocar site. CONCLUSIONS: Laparoscopic radical prostatectomy is feasible but currently offers no advantage over open surgery with regard to tumor removal, continence, potency, length of stay, convalescence, and cosmetic result.

New laparoscopic suturing device: initial clinical experience.

OBJECTIVES: New instrumentation and techniques have enabled laparoscopic surgeons to perform complicated reconstructive procedures. Few centers have attempted these procedures because of the excessive time involved with laparoscopic suturing. The Endo stitch suture device was developed to facilitate suture placement. We clinically compared conventional intracorporeal suturing and Endo Stitch suturing for laparoscopic suture placement and knot tying. METHODS: Intracorporeal suturing was used to complete laparoscopic dismembered pyeloplasties and bladder neck suspensions. Sutures were placed with either needle holders and graspers or the automatic suture device. A total of 85 maneuvers were assessed. Operative videotapes were reviewed to assess accuracy of suture placement, knot tying, and time to place suture and tie knots. All suturing was performed by an experienced laparoscopist. RESULTS: Accuracy of stitch placement and knot tying were equivalent. The average time for stitch placement with the Endo Stitch was 43 +/- 27 seconds (n = 41). This was significantly less than the average stitch placement time for conventional suturing, which was 151 +/- 24 seconds (n = 14). The Endo Stitch knot tying was completed in an average of 74 +/- 50 seconds (n = 17), whereas knot tying with the conventional technique took 197 +/- 70 seconds (n = 13). The needle is automatically loaded in the Endo Stitch after each suture and is immediately ready. CONCLUSIONS: The Endo Stitch device reduced the amount of time needed for placement of stitches and knot tying. Reconstructive laparoscopic procedures requiring multiple suture placement may be completed in a shorter time period using this instrument.

Laparoscopy for the acute abdomen in the postoperative urologic patient.

OBJECTIVES: Exploratory laparotomy offers the greatest diagnostic accuracy of intra-abdominal pathologic processes, but can be associated with significant morbidity. Laparoscopy provides diagnostic capabilities equivalent to that of open exploration, but with potentially less morbidity. We present 3 cases in which laparoscopy was used to diagnose and manage urologic patients with an acute abdomen in a postoperative period. METHODS: Three patients underwent laparoscopy between 1 and 14 days postoperatively for an acute abdomen (fever, elevated white blood cell count, and peritoneal signs). The initial procedures included a pubovaginal sling repair with fascia lata, endoscopic placement of a percutaneous gastrostomy tube, and a laparoscopic ureterolithotomy for a distal stone. RESULTS: In each of the 3 patients laparoscopy revealed misplacement or malfunction of a previously placed tube. In all cases, the patient was managed laparoscopically without the need for laparotomy. CONCLUSIONS: These cases demonstrate the feasibility of laparoscopy to provide diagnostic and therapeutic solutions to postoperative urologic patients presenting with an acute abdomen.

Effect of laparoscopic pelvic lymph node dissection on the natural history of D1 (T1-3, N1-3, M0) prostate cancer.

OBJECTIVES: Reports of abdominal wall tumor implantation after laparoscopic procedures have raised questions regarding the safety of laparoscopic surgery when applied to patients with malignancies. Our objective was to determine if laparoscopic pelvic lymph node dissection (LPLND) had a negative effect on tumor behavior and clinical outcome in men with Stage T1-3, N1-3, M0 (D1) prostate cancer. METHODS: Fifty-two men were retrospectively identified at four institutions who had pelvic nodes positive for metastatic prostate adenocarcinoma at LPLND and at least 1 year of follow-up. Operative and clinical records were reviewed to determine morbidity, adjuvant treatment, onset of hormone-resistant disease, and survival. RESULTS: During a mean follow-up of 3.1 years, there were no cases of trocar site tumor implantation. There were four perioperative complications, including enterotomy, epigastric vessel injury, abscess, and symptomatic lymphocele formation. There were three deaths from prostate cancer (5.8%) occurring 3 to 4 years after LPLND. For the 45 men treated with early androgen ablation, the 5-year biochemical prostate-specific antigen and clinical progression free rates were 45% and 55%, respectively. CONCLUSIONS: Abdominal wall tumor implantation after LPLND for prostate cancer was not demonstrated, even in patients who developed hormone-resistant disease. LPLND in men with Stage D1 disease did not alter short-term disease progression. Longer follow-up in a larger cohort is necessary to determine if LPLND will have an impact on the 5 and 10-year disease progression and survival rates for patients with Stage D1 prostate cancer.

Telesurgery. Remote monitoring and assistance during laparoscopy.

In comparison to open surgery, laparoscopy results in less postoperative pain, shorter hospitalization, more rapid return to the work force, a better cosmetic result, and a lower incidence of postoperative intra-abdominal adhesions. These advantages are indisputable when comparing large series for cholecystectomy and smaller series for pelvic lymph node dissection, nephrectomy, and bladder neck suspension in experienced hands. Urologists have an obligation to explore the application of these methods to urologic disease and to adjust the standard of care accordingly. Several barriers to the expansion of urologic laparoscopic surgery exist. The experience in extirpative and reconstructive urologic procedures is limited when compared with the data on cholecystectomy. These procedures are technically complex and demand advanced laparoscopic skills and familiarity with laparoscopic anatomy. The steep learning curve translates into long operative times and an unacceptably high rate of complications for inexperienced laparoscopic surgeons. Most practicing urologists have no formal training in advanced laparoscopy, and no formal credentialing guidelines exist. Telesurgical technology may provide one solution to this problem. Through telesurgical mentoring, less experienced surgeons with basic laparoscopic skills could receive training in advanced techniques from a world expert without the need for travel. These systems could also be used to proctor laparoscopic cases for credentialing purposes and to provide a more uniform standard of care. This review has outlined some of the exciting progress made in the field of telesurgery over the past 10 years and described some of the technical and legal obstacles that remain to be surmounted. During the 1990s, urologists were at the forefront of innovation in remote telepresence surgery. As the scope of minimally invasive urologic surgery expands during the first few decades of the twenty-first century, telesurgical mentoring should have an increasingly important role.

Laparoscopic infrared imaging.

BACKGROUND: As an adjunct to direct visual imaging, an infrared endoscope was developed to assist in the identification of various anatomic structures and to assess tissue viability during laparoscopic procedures. A camera sensitive to emitted energy in the mid-infrared range (3 to 5 microm) was incorporated into a two-channel visible-light laparoscope. METHODS AND MATERIALS: Laparoscopic procedures were performed in a porcine model, inexperienced laparoscopists being asked to localize and differentiate structures before dissection using the visible-light system and then the infrared system. To determine clinical utility, nine laparoscopic urologic procedures were performed with the assistance of the infrared system. RESULTS: In the clinical evaluation, infrared imaging proved to be useful in differentiating between blood vessels and other anatomic structures. In contrast to the experience with the conventional endoscope, vessel identification, assessment of organ perfusion, and transperitoneal localization of the ureter was successful in all instances using the infrared system. In the porcine model, this system also permitted assessment of bowel perfusion during laparoscopic occlusion of mesenteric vessels and distinguished between the cystic duct and artery. CONCLUSION: Infrared imaging is a potentially powerful adjunct to laparoscopic surgery. It may improve the differentiation and localization of anatomic structures and allow assessment of physiologic features, such as perfusion, not previously attainable with laparoscopic techniques.

Digital radiographic imaging transfer: comparison with plain radiographs.

Advances in digital imaging and computer display technology have allowed development of clinical teleradiographic systems. There are limited data assessing the effectiveness of such systems when applied to urologic pathology. In an effort to appraise the effectiveness of teleradiology in identifying renal calculi, the accuracy of findings on transmitted radiographic images were compared with those made when viewing the actual plain film. Plain films (KUB) were obtained from 26 patients who presented to the radiology department to rule out urinary calculous disease. The films were digitalized by a radiograph scanner into ARCNEMA-2 file format, compressed by a NASA algorithm, and transferred via a 28.8-kbps modern over standard telephone lines to a remote section 25 miles away, where they were decompressed and viewed on a 1600 x 1200-pixel monitor. Two attending urologists and two endourologic fellows were randomized to read either the transmitted image or the original radiograph with minimal clinical history provided. Of the 26 plain radiographic films, 24 were correctly interpreted by the fellows and 25 by the attending physicians (92% and 96% accuracy, respectively) for a total accuracy of 94% with no statistical difference (p = 0.16). After compression, all but one of the digital images were transferred successfully. The attending physicians correctly interpreted 24 of the 25 digital images (96%), whereas the fellows were correct on 21 interpretations (84%), resulting in a total 90% accuracy with a significant difference between the groups (p < or = 0.04). Overall, no statistical difference between the interpretations of the plain film and the digital image was revealed (p = 0.21). Using available technology, KUB images can be transmitted to a remote site, and the location of a stone can be determined correctly. Higher accuracy is demonstrated by experienced surgeons.

Laparoscopic renal surgery in patients at high risk for intra-abdominal or retroperitoneal scarring.

Prior open abdominal or renal surgery has been considered a relative contraindication to laparoscopic surgery because of the likelihood of adhesion formation and perinephric scarring, which results in difficulty obtaining access to the peritoneal cavity and during surgical dissection. The purpose of this study was to examine the feasibility and morbidity of laparoscopic renal surgery in patients at high risk for intra-abdominal or retroperitoneal scarring. Twenty-four patients who underwent laparoscopic renal surgery at our institution gave a history of significant open abdominal or renal surgery. Seven patients had undergone prior open extraperitoneal (N = 6) or percutaneous (N = 1) renal procedures, 10 patients had undergone prior open laparotomy for various reasons, and 7 patients had undergone open pelvic surgery. The mean interval from the prior operation to laparoscopic renal surgery was 16.5 years (range 0.3-44 years). Operative time, estimated blood loss, incidence of complications, perioperative parenteral narcotic use, length of hospitalization convalescence, and degree of intra-abdominal and retroperitoneal scarring were assessed. Patients who developed complications were compared with patients who did not. No difficulty was encountered while obtaining initial access to the peritoneal cavity or retroperitoneal space. No bowel or visceral injuries occurred during Veress needle or trocar placement. The laparoscopic procedure was completed successfully in all cases. The mean operative time was 4.3 (range 2.0-10.9) hours. The mean estimated blood loss was 266 mL (range 50-1200 mL). There were eight complications (overall complication 33%) including three major and five minor complications. Patients who developed complications had a higher total scarring score that those who did not (p = 0.01). For experienced laparoscopic surgeons, laparoscopic renal surgery in patients who have a history of open abdominal or renal surgery can be successful. Access via the transperitoneal or retroperitoneal route can be obtained safely, and the procedure usually can be performed in a timely fashion. However, a relatively high perioperative complication rate can be expected, particularly for those patients with significant intraperitoneal and retroperitoneal scarring.

Factors involved in gas embolism after laparoscopic injury to inferior vena cava.

This study evaluated the incidence and factors involved in the occurrence of gas embolism after laparoscopic injuries. A 5-MHz transesophageal echocardiographic (TEE) probe was placed in 11 anesthetized pigs and used to examine the right cardiac chambers and pulmonary artery. A calibrated carbon dioxide analyzer continuously measured end-tidal carbon dioxide (ETCO2). The ventilatory settings were adjusted to achieve a baseline ETCO2 between 25 and 28 mm Hg. A blinded dose-response curve for TEE and ETCO2 measurements were created by injecting 0.0007 to 1.5 mL/kg of CO2 gas intravenously. Venotomies (N = 22) were created laparoscopically in the inferior vena cava (IVC) of the study animals. All TEE images were videotaped and correlated with laparoscopic events. Embolic episodes were classified by comparison with images recorded during the bolus studies. A variety of methods for obtaining hemostasis and repairing the venotomies were evaluated and their effects on gas embolism were studied. No emboli were noted when the venotomies were bleeding freely, the hole was directly occluded, or the proximal IVC was compressed. Marked embolism was seen with distal IVC occlusion or when there had been significant blood loss. In this situation, manipulation of the hole and higher intraperitoneal pressures led to higher degrees of embolization. No emboli were seen in an open control group except after significant bleeding. The TEE is the most sensitive method of detecting gas emboli; however, the majority of episodes are not clinically significant. Embolism of CO2 occurs when central venous pressure is decreased by blood loss or distal compression. When significant venous bleeding occurs, intravascular volume should be maintained and the bleeding site should be directly occluded.

Laparoscopic nephrectomy: present state and future developments.

Laparoscopy has been a valuable tool in gynecologic practice for many years but it is only recently that this technology has been applied to urological surgery.1 Initially laparoscopy was used in urology only for di- agnostic purposes; however, following the success of laparoscopic cholecystectomy,' the technique was utilized to perform therapeutic procedures such as varicocelectomy and pelvic lymphadenectomy.v' Open surgery has been the standard for nephrectomy for over 100 years and the techniques, results, and complica- tions have been well documented in surgical texts. Laparoscopic nephrectomy is also a relatively new appli- cation, having only been first described in 1991.5 This article will review the current status of laparoscopic nephrectomy and speculate on its future role. The pros and cons of the laparoscopic technique when com- pared to open nephrectomy will also be discussed.

International surgical telementoring: our initial experience.

INTRODUCTION: Telesurgical laparoscopic telementoring has successfully been implemented between the Johns Hopkins Bayview Medical Center and the Johns Hopkins Hospital in 27 prior operations. In this previously reported series, telerobotic mentoring was achieved between two institutions 3.5 miles away. We report our experience in performing two international surgical telementoring operations. PURPOSE: To determine the clinical utility of international surgical telementoring during laparoscopic surgical procedures. METHOD: A laparoscopic adrenalectomy was telementored between Innsbruck, Austria (5,083 miles) and Baltimore, MD. As well, a laparoscopic varicocelectomy was telementored between Bangkok, Thailand and Baltimore, MD (10,880 miles) both over three ISDN lines (384 kbps) with an approximate 1 sec delay. RESULTS: Both procedures were successfully accomplished with an uneventful postoperative course. CONCLUSION: International telementoring is a viable method of instructing less experienced laparoscopic surgeons through potentially complex laparoscopic procedures, as well as potentially improving patient access to specialty care.

Abdominal Colpopexy: Comparison of Endoscopic Surgical Strategies (ACCESS).

INTRODUCTION: Robotic assistance during laparoscopic surgery for pelvic organ prolapse rapidly disseminated across the United States without level I data to support its benefit over traditional open and laparoscopic approaches [1]. This manuscript describes design and methodology of the Abdominal Colpopexy: Comparison of Endoscopic Surgical Strategies (ACCESS) Trial. METHODS: ACCESS is a randomized comparative effectiveness trial enrolling patients at two academic teaching facilities, UCLA (Los Angeles, CA) and Loyola University (Chicago, IL). The primary aim is to compare costs of robotic assisted versus pure laparoscopic abdominal sacrocolpopexy (RASC vs LASC). Following a clinical decision for minimally-invasive abdominal sacrocolpopexy (ASC) and research consent, participants with symptomatic stage≥II pelvic organ prolapse are randomized to LASC or RASC on the day of surgery. Costs of care are based on each patient's billing record and equipment costs at each hospital. All costs associated with surgical procedure including costs for robot and initial hospitalization and any re-hospitalization in the first 6weeks are compared between groups. Secondary outcomes include post-operative pain, anatomic outcomes, symptom severity and quality of life, and adverse events. Power calculation determined that 32 women in each arm would provide 95% power to detect a $2500 difference in total charges, using a two-sided two sample t-test with a significance level of 0.05. RESULTS: Enrollment was completed in May 2011. The 12-month follow-up was completed in May 2012. CONCLUSIONS: This is a multi-center study to assess cost as a primary outcome in a comparative effectiveness trial of LASC versus RASC.

Complications of laparoscopic living donor nephrectomy and their management: the UCLA experience.

OBJECTIVES: Because of the shortage of cadaveric kidneys, laparoscopic living donor nephrectomy (LLDN) has become a more common option for transplant recipients. The complication rate has been reported at 6.4% to 16.5%. We present the initial University of California, Los Angeles experience with the complications and their management during LLDN. METHODS: From January 2000 to December 2005, a single surgeon performed 300 consecutive LLDNs at our institution. A committee of urologists, nephrologists, and support staff approved each donor before surgery. After LLDN was completed, the patients received 30 mg of ketorolac intravenously every 6 hours until discharge. We reviewed the intraoperative and postoperative complications and their management at our institution. RESULTS: Three patients required open conversion, for an overall conversion rate of 1%. Two of the three conversions were a result of a major vascular complication (0.6%). The first major vascular complication resulted from an endovascular stapler malfunction during transection of an accessory left renal artery. The second vascular complication was a Veress needle injury to the left common iliac artery. Three postoperative major complications (1%) occurred, including 1 case of rhabdomyolysis and 2 cases of chylous ascites. Also, 7 minor postoperative complications (2.3%) occurred. Our overall complication rate was 4%. No patients died, and the mean hospital stay was 1.1 days. CONCLUSIONS: Our results have shown that LLDN is a safe procedure associated with low morbidity and a quick recovery. Appropriate patient selection is essential to ensure the safety of this procedure.

Positive margins in laparoscopic partial nephrectomy in 855 cases: a multi-institutional survey from the United States and Europe.

PURPOSE: Open partial nephrectomy has emerged as the standard of care in the management of renal tumors smaller than 4 cm. While laparoscopic radical nephrectomy has been shown to be comparable to open radical nephrectomy with respect to long-term outcomes, important questions remain unanswered regarding the oncological efficacy of laparoscopic partial nephrectomy. We examined the practice patterns and pathological outcomes following laparoscopic partial nephrectomy. MATERIALS AND METHODS: A survey was sent to academic medical centers in the United States and in Europe performing laparoscopic partial nephrectomy. The total number of laparoscopic partial nephrectomies, positive margins, indications for intraoperative frozen biopsy as well as tumor size and position were queried. RESULTS: Surveys suitable for analysis were received from 17 centers with a total of 855 laparoscopic partial nephrectomy cases. Mean tumor size was 2.7 cm (+/-0.6). There were 21 cases with positive margins on final pathology, giving an overall positive margin rate of 2.4%. Intraoperative frozen sections were performed selectively at 10 centers based on clinical suspicion of positive margins on excised tumor. Random biopsies were routinely performed on the resection bed at 5 centers. Frozen sections were never performed at 2 centers. Of the 21 cases with positive margins 14 underwent immediate radical nephrectomy based on the frozen section and 7 were followed expectantly. CONCLUSIONS: Early experience with laparoscopic partial nephrectomy in this multicenter study demonstrates oncological efficacy comparable to that of open partial nephrectomy with respect to the incidence of positive margins. The practice of intraoperative frozen sections varied among centers and is not definitive in guiding the optimal surgical treatment.