BioGlue surgical adhesive as a thermal reflector during laparoscopic cryoablation: effect on iceball size and ablation zone diameter.

BACKGROUND AND OBJECTIVES: Cryoablation represents an alternative for treating small renal cortical neoplasms (RCN). Previously, we demonstrated that applying BioGlue during cryoablation diminished bleeding and incidentally noted that the iceballs seemed larger than those in controls. We examined the effects of BioGlue as a thermal insulator of cryoablated tissue to determine its effect on iceball size. METHODS: Laparoscopic cryoablation (LCA) was performed in 6 female pigs (24 ablations) by using a single 1.47-mm cryoablation probe. One pole of each kidney was randomly treated with BioGlue prior to ablation, while the contralateral pole was the untreated control. The size of the iceball was measured using laparoscopic ultrasound. The tissue ablation zone was measured grossly after the specimens were harvested. We also documented the amount of bleeding on a subjective scale. RESULTS: There were no differences in the diameters of the iceballs between the BioGlue and control groups when measured with laparoscopic ultrasound (P=.85). Similarly, the ablation zones on gross measurement were not significantly different (P=.47). No difference occurred in the amount of subjective bleeding. CONCLUSIONS: In a porcine model, the application of BioGlue prior to LCA does not appear to increase the size of the iceball generated. No change was observed in the amount of subjective bleeding as a result of using BioGlue.

Clinical, pathologic, and functional outcomes after nephron-sparing surgery in patients with a solitary kidney: a multicenter experience.

BACKGROUND AND PURPOSE: Surgical management of a renal neoplasm in a solitary kidney is a balance between oncologic control and preservation of renal function. We analyzed patients with a renal mass in a solitary kidney undergoing nephron-sparing procedures to determine perioperative, oncologic, and renal functional outcomes. PATIENTS AND METHODS: A multicenter study was performed from 12 institutions. All patients with a functional or anatomic solitary kidney who underwent nephron-sparing surgery for one or more renal masses were included. Tumor size, complications, and recurrence rates were recorded. Renal function was assessed with serum creatinine level and estimated glomerular filtration rate. RESULTS: Ninety-eight patients underwent 105 ablations, and 100 patients underwent partial nephrectomy (PN). Preoperative estimated glomerular filtration rate (eGFR) was similar between the groups. Tumors managed with PN were significantly larger than those managed with ablation (P<0.001). Ablations were associated with a lower overall complication rate (9.5% vs 24%, P=0.01) and higher local recurrence rate (6.7% vs 3%, P=0.04). Eighty-four patients had a preoperative eGFR ≥60 mL/min/1.73 m(2). Among these patients, 19 (23%) fell below this threshold after 3 months and 15 (18%) at 12 months. Postoperatively, there was no significant difference in eGFR between the groups. CONCLUSIONS: Extirpation and ablation are both reasonable options for treatment. Ablation is more minimally invasive, albeit with higher recurrence rates compared with PN. Postoperative renal function is similar in both groups and is not affected by surgical approach.

Evaluation of perirenal fat as a predictor of cT 1a renal cortical neoplasm histopathology and surgical outcomes.

BACKGROUND AND PURPOSE: With the increasing detection of small renal cortical neoplasms (RCNs), the preoperative prediction of histopathology has become increasingly important. Because perirenal fat (PF) is known to be metabolically active, we evaluated PF as a predictor of renal tumor histopathology. PATIENTS AND METHODS: We retrospectively evaluated patients who underwent laparoscopic nephron-sparing procedures for cT(1a) RCN at two institutions. PF was measured using the digital measuring tool function on standard imaging software, at the level of the renal hilum as the perpendicular distance between the posterior surface of the kidney and the external margin of the psoas muscle. The Mann-Whitney test and logistic regression were used to examine PF, selected demographic, clinical, and operative parameters, and their association with tumor histopathology. RESULTS: Data from 250 patients were included in this study. There were 157 (63%) men and 93 (37%) women with a median body mass index (BMI) of 28 kg/m(2). Median tumor size was 2.4 cm, and the median PF distance was 12 mm. Significant correlations were noted between PF and sex and BMI. No significant correlations were found between PF and the operative parameters. Results of a multivariate logistic regression analysis revealed that PF (P<0.01), age (P<0.04), and tumor location (P<0.04) were significant predictors of clear-cell renal-cell carcinoma (RCC) histopathology. CONCLUSIONS: In this study, PF, location of tumor, and age were significant predictors of clear-cell RCC histopathology. The correlation of PF and histopathology may be useful in preoperative decision-making and surgical planning in the management of small RCN.

Independent diagnostic and post-treatment prognostic models for prostate cancer demonstrate significant correlation with disease progression end points.

BACKGROUND AND PURPOSE: A major advance in the standard practice of tissue-based pathology is the new discipline of systems pathology (SP) that uses computational modeling to combine clinical, pathologic, and molecular measurements to predict biologic activity. Recently, a SP-based prostate cancer (PCa) predictive model for both preoperative (Px+) and postoperative (Px) prostatectomy has been developed. The purpose of this study is to calculate the percent agreement and the concordance between the Px+ and Px end points. PATIENTS AND METHODS: Fifty-three patients underwent robot-assisted prostatectomy for PCa, and had Px+ and Px testing performed. Data were collected on Px+ end points and Px end points along with pathologic specimen results. The percent agreement and the degree of correlation between the Px+ and Px end points were then calculated. RESULTS: The percent agreement (PA) between Px+ end points and Px end points ranged from 77% to 87%. The PA between a high Px+ favorable pathology (FP) classification and dominant Gleason score ≤ 3 and Gleason sum ≤ 6 was 71.7% and 37.4%, respectively. On univariate analysis, Px+ disease progression (DP) score significantly correlated with Px prostate-specific antigen recurrence (PSAR) score (P<0.001), while Px+ DP probability significantly correlated with PxPSAR probability (P<0.001). Px+ FP probability significantly correlated with postprostatectomy dominant Gleason grade ≤ 3 (P<0.001) and Gleason sum (P<0.001). CONCLUSION: The PA between Px+ and Px testing end points for radical prostatectomy patients was very good. Furthermore, there was a direct correlation between most Px+ and Px end points. While the Px+FP classification and Gleason sum demonstrated a poor PA, Px+FP score still maintained a direct correlation to prostatectomy Gleason sum.

Nonischemic laparoscopic partial nephrectomy using a novel wet monopolar device in a porcine model.

BACKGROUND AND PURPOSE: Laparoscopic partial nephrectomy (LPN) is the minimally invasive standard of care for the management of a cT(1a) renal mass. We evaluated a novel saline enhanced electrosurgical resection (SEER) device for performance of a nonischemic LPN. MATERIALS AND METHODS: Six pigs were used in a nonsurvival pilot study. Energy penetration was characterized by applying the SEER to the lower pole of each kidney for 30 seconds, 1 minute, and 3 minutes using pure cutting energy at 100W and a drip rate of 1 drip per second. Energy testing was performed with the hilum clamped in six kidneys and without clamping in six kidneys. Subsequently, a nonischemic upper pole LPN was performed with the SEER device, and the kidneys were harvested. The areas of necrosis were sectioned and stained with hematoxylin and eosin. Depth of necrosis was visualized grossly and microscopically for each time point. We also recorded time to perform LPN, estimated blood loss (EBL), and subjective severity of bleeding. RESULTS: The average operative time was 15.4 minutes. The mean EBL was 44.2 mL with nine (75%) cases classified as minimal, 2 (17%) moderate, and 1 (8%) severe bleeding. The mean depth of necrosis on the kidney remnants was 2.97 mm. The mean depth of necrosis for unclamped kidneys at 30 seconds, 1 minute, and 3 minutes was 0.38 mm, 0.88 mm, and 1.27 mm, respectively. The mean depths for the clamped kidneys were 2.73 mm, 3.23 mm, and 8.68 mm respectively. Depth of necrosis was significantly higher in the clamped kidneys at 3 minutes (P=0.0035). CONCLUSIONS: In the porcine model, the SEER transected parenchyma and collecting system with low resection times and minimal blood loss. Use of coagulation during resection is the main advantage of a monopolar resection compared with cold scissors. Testing performed for 3 minutes during hilar clamping demonstrated a significantly deeper level of necrosis.

Retrospective comparison of laparoscopic partial nephrectomy versus laparoscopic renal cryoablation for small (<3.5 cm) cortical renal masses.

OBJECTIVE: We compared perioperative and short-term outcomes of renal laparoscopic partial nephrectomy (LPN) and laparoscopic cryoablation (LCA) in patients with small (<3.5 cm) renal cortical neoplasms. METHODS: A retrospective analysis from our prospectively established database was performed. We identified 92 patients with 95 lesions treated with LPN and 75 patients with 91 lesions treated with LCA. RESULTS: The LPN and LCA groups were comparable in mean tumor size and preoperative and postoperative creatinine level (P=.495, P=.953, and P=.101) respectively. Patients undergoing LPN were younger in age (58.8 versus 69.2 years, P<.001), had a higher mean estimated blood loss (168.4 versus 6 mL, P=.005), and had a prolonged mean operative time (151.6 versus 128.6 minutes, P=.01). Six complications occurred in the LCA group and 11 in the LPN group. The median follow-up time was 21.8 months for LPN and 14 months for LCA (P<.001). Two recurrences were detected in the LCA group, and 1 recurrence was reported after LPN. CONCLUSIONS: In the treatment of small renal cortical neoplasms with short-term follow-up, LPN and LCA seem to be equally effective. LCA offers decreased blood loss, shorter operative time, and less morbidity. Longer follow-up is required to establish oncologic efficacy.

Prospective randomized evaluation of gel mat foot pads in the endoscopic suite.

BACKGROUND AND PURPOSE: Several studies that compare open and laparoscopic procedures have demonstrated that the minimally invasive surgeon has greater musculoskeletal pain when compared with open surgeons. The purpose of our study was to demonstrate whether the use of the gel mat in the endoscopic setting offered any ergonomic benefit to the surgeon. MATERIALS AND METHODS: One hundred endoscopic procedures, by 11 different surgeons, were randomized intostudy (use of a gel mat) and control groups. Procedures included both percutaneous nephrolithotomies and ureteroscopies and were randomized without regard to the type or expected length of the procedure. All subjects completed a preoperative, intraoperative, immediate postoperative, and 24-hour postoperative questionnaire. During the procedures, an independent observer recorded the number of intraoperative stretches and positional changes because of discomfort. RESULTS: The mean preoperative metrics for the gel mat and no gel mat groups were similar with the exception of the ≤60-minute group, whose members found the gel mat group starting with greater overall discomfort (1.7 vs 1.3, P=0.0273). In the ≤60 minute group, gel mat use significantly decreased postoperative discomfort (P=0.0435) and improved postoperative energy (P=0.0411). In those procedures >60 minutes, the gel mat improved postoperative discomfort and energy as well as the number of stretches and postural changes during the procedure. CONCLUSION: Application of gel mats in the endoscopic setting improves surgeon overall postoperative discomfort and energy in all cases. For cases >60 minutes duration, gel mats also decrease the number of stretches and postural changes from discomfort. Some of these salutary effects may translate into more efficient surgery and better patient outcomes.

Validating the use of the Mimic dV-trainer for robotic surgery skill acquisition among urology residents.

OBJECTIVE: To compare robotic surgery skill acquisition of residents trained with Mimic dVTrainer (MdVT) and da Vinci Surgical System (dVSS) console. No standardized curriculum currently exists for robotic surgical education. The MdVT is a compact hardware platform that closely reproduces the experience of the dVSS. METHODS: Sixteen urology trainees were randomized into 3 groups. A baseline evaluation using dVSS was performed and consisted of 2 exercises requiring endowrist manipulation (EM), camera movement and clutching (CC), needle control (NC), and knot-tying (KT). Groups 1 and 2 completed a standardized training curriculum on MdVT and dVSS, respectively. Group 3 received no additional training. After completion of the training phase, all trainees completed a secondary evaluation on dVSS consisting of the same exercises performed during baseline evaluation. RESULTS: There was no difference in baseline performance scores across the 3 groups. Although Group 3 showed no significant improvement in EM/CC domain (P = .15), Groups 1 and 2 had statistically significant improvement in EM/CC domain (P = .039 and P = .007, respectively). The difference in improvement between Groups 1 and group 2 was not statistically different (P = .21). Only Group 2 trainees showed significant improvement in the NC and KT domains during secondary evaluation (P = .02). CONCLUSION: Curriculum-based training with MdVT or dVSS significantly improves robotic surgery aptitude. Similar improvements are seen for exercise domains shared between MdVT and dVSS groups. Follow-up studies are necessary to assess the efficacy of MdVT over a wider spectrum of domains.

Pilot study evaluation of standard laparoscopic suturing and a novel parenchymal apposition mechanism for minimally invasive renal reconstruction.

OBJECTIVES: The most technically demanding portion of a laparoscopic partial nephrectomy is the renorrhaphy. The purpose of this study was to determine whether a parenchymal apposition mechanism (PAM) device would be as effective as standard laparoscopic technique (SLT) with respect to efficiency, capability, and safety of renal defect closure. MATERIALS AND METHODS: In this pilot study, participants were recruited to perform surgical reconstruction of a standardized renal parenchymal defect with both SLT and the PAM. The PAM prototype was engineered using two salmon egg hooks connected by absorbable suture and placed within a V-shaped foam delivery mechanism. After hook placement, tensioning of the connecting suture using a Weck clip apposed the defect edges. Each participant performed a single closure with SLT and with the PAM device of a standardized defect in ex vivo porcine kidneys. Closure time, tissue trauma/damage during closure, and the intraparenchymal pressure were recorded. RESULTS: A total of 13 subjects, 7 medical students, 3 residents, 2 fellows, and 1 attending were enrolled. There was no statistical difference between the two methods of closure in average time for closure. In a subgroup analysis of subjects who had performed laparoscopic reconstructive procedures as the primary surgeon, SLT was significantly faster than PAM (P=.036). Mean pressures achieved in attempted closure using SLT and PAM were not significantly different (0.38 N for both groups; P=.99). The mean parenchymal trauma rating was not significantly different between the groups; however, the upper limit of the range of trauma ratings was greater in the standard closures. CONCLUSION: This pilot study demonstrated the feasibility of PAM use in an ex vivo porcine kidney model. Additional testing and continued design modifications are necessary to explore its use in laparoscopic reconstruction of the kidney and other organs.

Polyglyconate unidirectional barbed suture for posterior reconstruction and anastomosis during robot-assisted prostatectomy: effect on procedure time, efficacy, and minimum 6-month follow-up.

BACKGROUND AND PURPOSE: With widespread implementation of posterior rhabdosphincter reconstruction (RSR) followed by urethrovesical anastomosis (UVA), reconstruction has become a significant portion of robot-assisted laparoscopic prostatectomy (RALP). Successful anastomosis can be measured by time for reconstruction and the absence of urinary leak. We prospectively evaluated the experience of a single surgeon (KKB) in using the V-Loc™ wound closure device for the posterior RSR and UVA, and compared it with a standard reconstruction and anastomosis. PATIENTS AND METHODS: A total of 84 patients divided into two groups underwent RALP, undergoing RSR and UVA using a Van Velthoven technique with the V-Loc or with a standard 3-0 monofilament suture. The primary end point was the time to complete RSR, UVA, and the total reconstruction. As a secondary end point, the clinical evidence of an anastomotic leak was also documented. RESULTS: The mean RSR, UVA, and total times were 9, 18, and 27 minutes for the control group, and 6, 12 and 18 minutes for the V-Loc group, respectively. The time differences between the two groups for RSR, UVA, and total time were 3 minutes (P<0.01), 6 minutes (P<0.01), and 9 minutes (P<0.001), respectively. There was no clinical evidence of anastomotic leak in either group. Continence recovery was equivalent between the groups at 6 weeks and 6 months. At a 9-month follow-up, no patients in either group had a clinical UVA stricture necessitating intervention. CONCLUSIONS: The V-Loc suture is associated with a significantly shorter time for the RSR and UVA compared with the traditional suture and is not associated with a higher incidence of clinical urinary leak; however, a larger randomized study with long-term follow-up is necessary to confirm these results.

BioGlue iceball stabilization to minimize the risk of hemorrhage during laparoscopic renal cryoablation.

OBJECTIVE: To evaluate the application of a BioGlue adhesive shell to minimize iceball fracture. Iceball fracture and hemorrhage is common with laparoscopic cryoablation (LCA) of larger (>4 cm) renal tumors. METHODS: Twenty large iceballs were created in porcine kidneys using 3 cryoablation probes in a nonsurvival study. Each kidney underwent an upper and lower pole ablation. One pole in each kidney was covered with 5 mL of BioGlue and the opposite pole served as a control. A double freeze-thaw cycle was performed (10 minutes freeze and 5 minutes active thaw) in both renal poles simultaneously. The probes were removed and the sites were monitored for 20 minutes under direct vision. Fracture length (mm), severity of fracture depth, severity of bleeding (absent, mild, moderate, severe), and estimated blood loss (EBL) (mL) were recorded. RESULTS: In the control group, the mean fracture length was 1.9 mm (range, 0-3 mm). Blood loss was absent in 10%, mild in 60%, and moderate in 30% of ablations. The mean EBL was 20.5 mL (range, 0-50 mL). For the BioGlue ablations, there were no parenchymal fractures. Blood loss was mild in 30% and absent in 70% of sites with an average EBL of 5 mL (range, 0-20). Two bleeding sites occurred as a result of subcapsular hematomas caused by initial probe placement. CONCLUSIONS: BioGlue application minimized the frequency and magnitude of renal fracture. EBL was lower with BioGlue application and most sites demonstrated no postablation bleeding. Further clinical study of the BioGlue shell should be performed to confirm these results.

Comparison of distal ureteral management strategies during laparoscopic nephroureterectomy.

BACKGROUND AND PURPOSE: The optimal approach for management of the distal ureter and bladder cuff (DUBC) during laparoscopic nephroureterectomy (LNU) for upper-tract transitional-cell carcinoma (TCC) is controversial. We describe our contemporary experience with LNU and compare several approaches to the DUBC. PATIENTS AND METHODS: A retrospective analysis was performed on 36 patients undergoing LNU. Three approaches to the DUBC were used: Open resection (OR), complete laparoscopic dissection and suture reconstruction (LR), and laparoscopic dissection with DUBC stapling (LS). Patient demographics and intraoperative, perioperative, and pathologic variables were compared. Estimated 2-year recurrence-free survival (RFS) was calculated. RESULTS: A total of 36 patients were analyzed: 10 OR, 12 LR, and 14 LS. The mean age was 69.6 years with a mean follow-up of 15 months. The LR and LS groups had significantly shorter operative times compared with the OR group (163 and 152 vs 276 minutes, respectively (P<0.05). The LR group had the shortest mean length of stay compared with the OR and LS groups (2.0 vs 3.5 and 2.7 days, respectively, P<0.05). No patient had a complete ureteral orifice, but a cystoscopically appreciable remnant of the resected ureteral orifice was noted in 50% of the LS group vs none with the LR and OR groups (P<0.05). The estimated 2-year RFS was 65% for the entire cohort with no significant differences among groups. CONCLUSIONS: Complete laparoscopic resection of the DUBC is feasible, particularly in low-stage, low-grade upper tract TCC and provides benefits such as shorter operative times and length of stay compared with an open bladder cuff excision.

Minimally invasive percutaneous ablation of parapelvic renal cysts and caliceal diverticula using bipolar energy.

BACKGROUND AND PURPOSE: The use of bipolar electrocautery has proven advantages over monopolar energy during transurethral surgery by limiting hyponatremia and its clinical sequelae. Percutaneous ablation of caliceal diverticula and parapelvic renal cysts has been shown to be an effective surgical approach for the management of these conditions when clinically indicated. We present single center results of percutaneous ablation of renal cysts and caliceal diverticula using a bipolar energy technique and compare the results with a cohort of patients undergoing the procedure using monopolar energy. PATIENTS AND METHODS: Between July 2006 and June 2010, 30 patients with caliceal diverticula and renal cysts underwent percutaneous ablation using the bipolar resection system with saline irrigation (group 1). This group was compared with a cohort of 19 patients who underwent traditional ablation using a standard resectoscope, monopolar energy, and glycine irrigation (group 2). We evaluated operative times, change in hematocrit and serum sodium levels from preoperative levels, complication rates, as well as symptomatic and radiographic success rates. RESULTS: The mean operative times were 87 minutes and 63 minutes for groups 1 and 2, respectively (P = 0.07). The mean percent decrease in hematocrit was 3.27 ± 1.93 in group 1 and 3.82 ± 2.09 in group 2 (P = 0.16), and the mean decrease in serum sodium level was -0.21 ± 2.24 mEq/L in group 1 and 3.78 ± 2.18 mEq/L in group 2 (P < 0.001). There were no intraoperative complications. One patient needed ureteral stent placement for persistent urine leak. All patients with symptomatic renal cysts reported resolution of their discomfort, with radiographic success confirmed in 89% in group 1 and 79% in group 2 (P = 0.41). CONCLUSIONS: Percutaneous ablation of caliceal diverticula and renal cysts using a bipolar resection system is feasible and appears to have efficacy similar to that of the monopolar system. In addition, use of isotonic saline as the irrigation medium appears to reduce the risk of postoperative hyponatremia.

Contemporary experience with laparoscopic partial nephrectomy.

INTRODUCTION: We evaluated our contemporary outcomes with laparoscopic partial nephrectomy (LPN) for renal cortical neoplasms (RCN) by an experienced single surgeon in our last 100 consecutive patients. METHODS: We reviewed a prospectively established database and identified 378 patients who underwent LPN for RCN. Data from the most recent 100 consecutive patients (June 2007 to August 2009) were evaluated for oncologic, functional, and recovery outcomes, and tumors were stratified by size. There were 57 men and 43 women. The mean tumor size was 2.8 cm (range 0.9-9.0 cm). RESULTS: The mean operative time was 132 minutes (range 95-350 minutes) and the mean blood loss was 175 mL (range 25-1000 mL). There were 13 (13%) complications. Seventy-seven tumors were ≤4 cm (group 1) and 23 tumors were >4 cm (group 2). The groups were similar in terms of demographics, perioperative data, and complications. The mean warm ischemia time in groups 1 and 2 were 25.9 and 29.5 minutes, respectively (P=.04). Overall, 79% of the tumors were malignant renal cell carcinoma variants with a positive margin rate of 2%. With a median follow-up of 8 months, there was 1 local recurrence. The median change between preoperative estimated glomerular filtration rate and 3 months' follow-up estimated glomerular filtration rate was 10.1 mL per minute per 1.73 m(2) (P>.001). CONCLUSIONS: LPN is a safe and effective treatment option for RCN. With extensive experience and a well-developed surgical technique, patient outcomes are improved and postoperative complications are reduced. LPN may be applied to more complex cases including larger and hilar tumors.

Active surveillance of renal cortical neoplasms: a contemporary review.

INTRODUCTION: Over the past 2 decades, there has been a significant increase in the number of incidentally found small renal cortical neoplasms (RCNs). As more RCNs are being discovered in the elderly and infirmed patient populations, there has been a growing interest in the role of active surveillance (AS). Active surveillance is recommended for high surgical-risk patients and those with a reduced life expectancy. It is also an option for patients wishing to avoid surgery. We review the current literature on AS and highlight the natural history of disease, the important factors to evaluate during AS, and the contemporary role of biopsy. METHODS AND MATERIALS: The MEDLINE database was searched using PubMed. Search terms included active surveillance, renal mass, natural history, and renal mass histology. From 1966 to present, 17 AS series were identified, all of which have been included in this summary. A summary was performed by compiling all available data and performing a weighted mean where applicable. RESULTS: Initial tumor size does not correlate with growth rate or malignancy. The mean growth rate in large published series is low (0.28-0.34 cm/year). Tumors with high growth rates usually represent malignant lesions and typically undergo delayed intervention. Progression to metatatic disease is a low-probability event for tumors on AS (1.4%); however, this is still a risk that patients must be willing to accept. Larger tumors (cT1b and cT2) also demonstrate relatively low growth (0.57 cm/year); however, these tumors should be monitored carefully. Tumors followed for > 5 years demonstrate a low growth rate (0.15 cm/year), will not likely require intervention, and have a low chance of progression to metastatic disease. CONCLUSION: For highly selected patients with RCN, AS is a reasonable treatment option. Age, surgical risk, comorbidities, and patient opinion must all factor into the final decision when considering a patient for AS.

Laparoscopic ablation of renal neoplasms.

As a result of the widespread application of cross sectional imaging, there has been a significant rise in the incidence of small renal cortical neoplasms. The current standard of care in the management of these lesions is nephron-sparing extirpative surgery. In the last decade, however, image-guided or ablative therapies have garnered significant attention as nephron-sparing alternatives to partial nephrectomy. Although initially laparoscopic ablation was predominately intended for use as active treatment in those patients in whom more invasive therapy was contraindicated, as experience with laparoscopic ablation has become more robust, the indications for the procedure continue to evolve. The current article reviews the indications and contraindications, preoperative preparation, surgical technique, and postoperative follow-up for laparoscopic ablative procedures. Also discussed are techniques and patient selection criteria to avoid complications, as well as the management of complications that do occur.

Robotic instrument insulation failure: initial report of a potential source of patient injury.

OBJECTIVES: To report our experience with failures in the accessory tip covers that insulate the monopolar robotic cautery scissor instruments and the patient injuries that have resulted. Currently, there is no data in the literature regarding the failure rate of robotic instruments or their accessory components. METHODS: All robotic surgeries performed at our institution were recorded from July 2008 to January 2009. Instrument tip cover failures were recorded at the time of failure regardless of whether a patient complication occurred. Failure was identified by the arching of the electrical current from the insulated portion of the monopolar scissors or by an intraoperative injury. RESULTS: Four-hundred fifty-four robotic procedures were recorded. A total of 12 accessory tip cover failures were discovered, demonstrating a failure rate of 2.6%, with a patient complication rate of 0.6% (25% of all failures). CONCLUSIONS: Failure in robotic accessory tip covers can lead to patient complications. The cause for failure can be attributed to a variety of electrical and mechanical causes. All centers and surgeons performing robotic surgery should be aware of the potential for this problem to occur, and the possible interventions that may reduce tip cover failure.

Natural history of renal cortical neoplasms during active surveillance with follow-up longer than 5 years.

OBJECTIVES: To present our experience with patients who elected active surveillance for renal cortical neoplasms (RCNs) with ≥5 years of follow-up. Few data are available regarding the long-term natural history of RCNs during surveillance. METHODS: We retrospectively reviewed our urologic oncology database and identified 44 patients with 51 RCNs who had received active surveillance for >5 years of follow-up. The patient and tumor characteristics and tumor growth rate and overall survival data were evaluated. RESULTS: The median patient age was 71.7 years (range 55-92), with 32 patients (72.7%) having a Charlson comorbidity index of ≥2. The median tumor size was 2.67 cm (range 0.9-8.6) at diagnosis. Biopsy was performed in 17 patients (38.6%). Of these 17 patients, clear cell renal cell carcinoma was diagnosed in 15 and papillary renal cell carcinoma in 2 patients. The median follow-up was 77.1 months (range 60-137), and the median growth rate was 0.15 cm/y. Of these patients, 2 (4.5%) required delayed intervention. One underwent laparoscopic radical nephrectomy because of a high tumor growth rate, and one elected to withdraw from active surveillance because of personal anxiety, despite having a stable tumor size for 72 months. The latter patient underwent laparoscopic renal cryoablation. Histopathologic examination revealed clear cell renal cell carcinoma in both cases. No metastases or cancer-related deaths occurred in our cohort; 1 patient died of cardiovascular disease. CONCLUSIONS: Most RCNs undergoing surveillance for >5 years grew slowly. The metastatic potential appeared minimal in patients who demonstrated low or absent tumor growth for a long period.

Comparison of two core biopsy techniques before and after laparoscopic cryoablation of small renal cortical neoplasms.

INTRODUCTION: Cryoablation is an acceptable treatment option for small renal cortical neoplasms (RCN). Unlike extirpative interventions, intraoperative needle biopsy is the only pathologic data for ablated tumors. It is imperative that sampled tissue accurately captures pathology. We studied the optimal intraoperative needle core biopsy protocol for small RCN during laparoscopic renal cryoablation (LCA). METHODS: Patients with RCN<4cm underwent intraoperative biopsy during LCA. Four biopsy cores were taken per tumor, 2 before and 2 after LCA by using both a standard and modified technique. Standard technique: needle biopsy device was deployed after insertion into the renal tissue at a depth of 5mm. Modified technique: needle biopsy device was deployed 1mm outside of the renal tissue. Biopsies were examined and compared with reference standard pathology. Percentage agreement was calculated across biopsy types (standard vs. modified) and time points (pre- vs. postcryoablation). Logistic regression was used to identify factors impacting biopsy accuracy. RESULTS: Thirty patients with 33 RCNs underwent LCA. The mean patient age was 69.1±8.0yrs, and mean tumor size was 2.3±0.7cm. No significant bleeding resulted from biopsies. A definitive diagnosis was made in 31/33 RCNs (94.0%). Ten tumors (30.3%) were benign, 21 (63.7%) were malignant, and 2 (6.0%) were nondiagnostic. Biopsy length was significantly longer using the standard vs. modified technique with mean lengths of 9.3mm vs. 7.0mm, respectively (P=.02). Highest agreement was seen in preablation biopsies (90.3%). A significant association with agreement was seen for younger age (P=.05) and larger tumor size (P=.02). CONCLUSIONS: Younger age and larger tumor size were associated with improved accuracy. Preoperative sampling resulted in superior accuracy and the standard technique resulted in significantly longer cores. Use of preablation standard biopsy technique may result in the most accurate pathologic diagnosis for patients undergoing cryoablation for small RCNs.

Contemporary experience with laparoscopic radical nephrectomy.

INTRODUCTION: We present our single-center contemporary experience with laparoscopic radical nephrectomy (LRN). LRN is an established minimally invasive approach comparable to open radical nephrectomy for the treatment of renal cortical neoplasms. Technical advancements and surgical experience with LRN mandate a re-evaluation of contemporary outcomes. METHODS: Between June 2005 and July 2009, 74 patients underwent LRN for an enhancing renal mass. Six of these patients underwent a cytoreductive nephrectomy for metastatic renal cell carcinoma. Patient demographics, perioperative data, tumor characteristics, complication rates, and outcomes were retrospectively collected and analyzed from our prospectively established renal database. RESULTS: The mean follow-up for patients undergoing nephrectomy without metastasis was 17.4 months (1-52 months). The mean estimated blood loss was 93 mL (0-600 mL) and the overall complication rate was 5.9%. Two patients developed metastatic disease after surgery, both of whom had high-stage (pT3a) tumors. No death was caused by renal cell carcinoma. In the cytoreductive cohort, the mean estimated blood loss was 592 mL (200-1200 mL). Four were high stage (pT3a/pT3b). The mean follow-up was 4.7 months (1-15 months), with an overall survival of 50%. CONCLUSIONS: With contemporary technology and increased laparoscopic surgical experience, LRN and, in selected cases, cytoreductive LRN can be performed safely and effectively for the majority of renal tumors. Experience has resulted in a reduction in operative time and blood loss complication rates. LRN remains the approach of choice for the management of renal cortical neoplasms not amenable to nephron-sparing surgery.