Comparison of Intraoperative Parameters and Perioperative Complications of Retroperitoneal and Transperitoneal Approaches to Laparoscopic Partial Nephrectomy: Support for a Retroperitoneal Approach in Selected Patients

Tumor morphology evaluation using 3D-morphometric features of renal masses

OBJECTIVE

To assess the correlation between the general (gender, age, and maximum tumor size) and 3D morphotopometric features of the renal tumor node, following the MSCT data post-processing, and the tumor histological structure; to propose an equation allowing for kidney malignancy assessment based on general and morphometric features.

MATERIALS AND METHODS

In total, 304 patients with unilateral solitary renal neoplasms underwent laparoscopic (retroperitoneoscopic) or robotic partial or radical nephrectomy. Before the procedure, kidney contrast-enhanced MSCT followed by the tumor 3D-modeling was performed. 3D model of the kidney tumor, and its morphotopometric features, and histological structure were analyzed. The morphotopometric ones include the side of the lesion, location by segments, the surface where the tumor, the depth of the tumor invasion into the kidney, and the shape of tumor.

RESULTS

Out of 304 patients, 254 (83.6%) had malignant kidney tumors and 50 (16.4%) benign kidney tumors. In total, 231 patients, out of 254 (90.9%) were assessed for the degree of malignant tumor differentiation. Malignant tumors were more frequent in men than in women (p < 0.001). Mushroom-shaped tumors were the most common shapes among benign renal masses (35.2%). The most common malignant kidney tumors had spherical with a partially uneven surface (27.6%), multinodular (tuberous (27.2%)), and spherical with a conical base (24.8%) shapes. Logistic regression model enabled the development of prognostic equation for tumor malignancy prediction ("low" or "high"). The univariate analysis revealed the correlation only between high differentiation (G1) and a spherical tumor with a conical base (p = 0.029).

CONCLUSION

The resulting logistic model, based on the analysis of such predictors as gender and form of kidney lesions, demonstrated a large share (87.6%) of correct predictions of the kidney tumor malignancy.

The Adhesive Perinephric Fat Score is Correlated with Outcomes of Retroperitoneal Laparoscopic Adrenalectomy for Benign Diseases

Background

Retroperitoneal laparoscopic adrenalectomy (RLA) possessing unique superiority with minimal abdominal interference is complicated by the status of periadrenal fat, including its quantity and texture. We hypothesized that an adherent perinephric fat predictor, the Mayo Adhesive Probability score (Mayo score), is associated with the perioperative outcomes of RLA.

Methods

This retrospective study included consecutive patients who underwent RLA for the diagnosis of benign adrenal tumors at our institution between 2017 and 2020. Medical records were reviewed to evaluate the association between Mayo scores obtained from preoperative computed tomography imaging and surgical outcomes as well as complications. Factors independently related to perioperative results were analyzed using multivariable regression models.

Results

In total, 186 RLA were included. According to their Mayo scores, the patients were divided as follows: 0 (n = 51, 27.4%), 1 (n = 34, 18.3%), 2 (n = 45, 24.2%), 3 (n = 29, 15.6%), 4 (n = 16, 8.6%) and 5 (n = 11, 5.9%). Longer operative time (92.0 ± 25.0 vs. 114.7 ± 30.6 vs. 137.4 ± 27.1 min, P < 0.001), higher estimated blood loss (42.2 ± 28.1 vs. 70.5 ± 44.9 vs. 132.6 ± 63.4 mL, P < 0.001) and greater decline of hemoglobin (0.7 ± 0.4 vs. 1.0 ± 0.4 vs. 1.3 ± 0.6 g/dL, P < 0.001) were significantly associated with elevated Mayo score risks. No difference in complication rates was found. The score was identified as a unique, independent risk factor for perioperative outcomes on multivariable analysis.

Conclusions

The Mayo score is a vital outcome predictor of RLA. It may be utilized in the preoperative planning for patients undergoing RLA.

A comparison of surgical practice and operative outcomes between retroperitoneal and transperitoneal laparoscopic nephrectomies – 6 years of data from the BAUS Nephrectomy database

Objectives:

While the choice of surgical approach for laparoscopic nephrectomy is broadly split between transperitoneal and retroperitoneal options, the evidence for the impact of this decision on perioperative outcomes is built on relatively small volume data, with often inconsistent findings and conclusions. We aimed to assess the impact of operative approach on perioperative outcomes for laparoscopic radical, partial and simple nephrectomy and nephroureterectomy through analysis of the British Association of Urological Surgeons (BAUS) Nephrectomy database.

Patients and methods:

All patients added to the BAUS Nephrectomy database with laparoscopic surgery between 2012 and 2017 inclusively were included and subdivided by operation and surgical approach. Preoperative patient and tumour characteristics, as well as intraoperative and post-operative short-term outcomes, were assessed.

Results:

Overall, 26,682 operations were documented over the review window (81.6% transperitoneal). Small increases in blood loss ( p = 0.001), transfusion rate ( p = 0.02) and operative length ( p = 0.01) were seen for transperitoneal radical nephrectomies and longer hospital stays seen for retroperitoneal procedures (radical nephrectomy p = 0.00l; partial nephrectomy p = 0.04). Retroperitoneal procedures were associated with increased rates of conversion for simple nephrectomy ( p = 0.02), nephroureterectomy ( p = 0.03) and most notably partial nephrectomy (10.5% versus 4.4%; p = 0.001). No further variation in intraoperative complications, post-operative complications, tumour margin positivity rates, unintended ITU admission, or likelihood of death was identified related to surgical approach.

Conclusion:

Observed variations in perioperative outcomes were generally modest in nature, and little ground is seen to support a change in operative technique for those committed to one approach. A caveat to this exists with open conversion for retroperitoneal partial nephrectomies and requires careful consideration of patient selection by the individual surgeon.

Level of evidence:

4

Predicting operation time and creating a difficulty scoring system in donor nephrectomy

BACKGROUND

To determine predictive formulas for operation time and surgical difficulty in laparoscopic living-donor kidney transplantation.

METHODS

We retrospectively analyzed data for 222 living donors aged > 20 years and recorded factors affecting operation time from patients' computed tomography images and medical records. We used the factors significantly affecting operation time to create a formula to predict operation time and designed a model to predict surgical difficulty based on the standardized partial regression coefficient, β. We also analyzed the relationship between surgical difficulty (high vs low) and operation time.

RESULTS

This study involved 111 pure retroperitoneal donor nephrectomies (PRDN) and 111 hand-assisted laparoscopic donor nephrectomies (HALDN). Patients' mean age was 55.7 years, and 59.5% were women; 5.0% underwent right nephrectomy, and 77.0% vs. 23.0% had single- vs. multiple renal arteries. The average estimated kidney graft weight was 160.0 g; actual average graft weight was 155.3 g. The following factors were significantly correlated with operation time in the regression analysis: number of renal arteries, Mayo adhesive probability (MAP) score, estimated kidney graft weight, right nephrectomy, and operation type (PRDN). These five factors were used to create the operation time prediction equation and difficulty scoring system. The multiple r2 value was 0.40 for the operation time prediction equation. Receiver operating characteristic curve analysis of the difficulty scoring system revealed the following: sensitivity: 78.0%, specificity: 64.9%, and c-statistic: 0.76 (95% confidence interval: 0.70-0.83).

CONCLUSIONS

The equation to predict operation time and the surgical difficulty prediction model created in this study are easy to calculate and are accurate. Both may help in selecting an appropriately-skilled surgeon and in improving safety in living-donor kidney transplantation.

Transperitoneal and retroperitoneal approach in laparoscopic partial nephrectomy for posterior cT1 renal tumors: A retrospective, two-centers, comparative study

OBJECTIVES

To compare perioperative, oncological and functional outcomes of Laparoscopic Transperitoneal Partial Nephrectomy (LTPN) and Retroperitoneal Laparoscopic Partial Nephrectomy (LRPN) for posterior, cT1 renal masses (RMs).

MATERIALS AND METHODS

Databases of two urologic institutions applying different laparoscopic surgical approaches on posterior cT1 RMs between June 2016 and November 2018 were retrospectively evaluated. Data on patient demographics, perioperative data and tumor histology were collected and further analyzed statistically.

RESULTS

Each group consisted of 15 patients. Baseline characteristics were comparable in each group. When compared to LTPN, LRPN was associated with significantly shorter operative time (OT) (115 min versus 199 min, p < 0.05). No significant differences were detected in the other outcomes.

CONCLUSIONS

LRPN is associated with a significantly shorter OT compared to LTPN for posterior cT1 RMs. Both surgical approaches are safe, feasible and credible, demonstrating optimal results.

Retroperitoneoscopic approach for highly complex posterior renal hilar tumors

Objectives:

To show our single-center experience in retroperitoneoscopic approach for highly complex posterior hilar tumors. Minimally invasive nephron sparing surgery for renal hilar tumors is extremely challenging due to their anatomic location, close to the main renal vessels and the collecting system (1). Transperitoneal approach is feasible, but highly complex because the anterior disposition of the vasculature. Retroperitoneal approach can easily provide access to the posterior hilar structures and the posterolateral surface of the kidney(2, 3).

Materials and Methods:

We retrospectively reviewed our hilar renal tumor database and analyzed those in which a retroperitoneoscopic approach was chosen. The RENAL score was then calculated, and operative and ischemia times were recorded. We also collected the mean hospital stay and the presence of complications. Pathology reports and follow-up were also gathered.

Results:

Five of our twelve highly complex hilar renal tumor patients were treated using a retroperitoneoscopic approach. Mean RENAL score was 10. Mean operative time was 135 minutes. Mean warm ischemia time was 14 minutes. Mean hospital stay was 4 days. We have recorded 2 complications. One patient required a transfusion and another presented with an urinary fistula which was treated by double J stent placement. The pathology report showed a clear cell renal cell carcinoma pT1a in most of the cases. Only one patient had a positive margin. To date, no recurrences have been noticed.

Conclusions:

The treatment of complex renal hilar tumors in a minimally invasive fashion is highly challenging even in experienced hands. Retroperitoneal partial nephrectomy is feasible, safe and effective for the treatment of such lesions. Long-term oncologic outcomes of this approach are awaited.

Laparoscopic Nephrectomy in Patients with Previous Abdominal Surgery

Laparoscopic nephrectomy is a minimally invasive procedure that provides significant benefits to the patient, such as reduced analgesic requirements and shorter recovery time. While the popularity of laparoscopy has grown substantially, there are associated risks of injury to the blood vessels and/or viscera during the insertion of the laparoscopic ports. Such injuries can lead to a significant increase in mortality rates. Patients who have had previous abdominal surgery have a higher risk of adhesions; this has been shown to increase the risk of complications from port placement. Consequently, previous abdominal surgery was viewed as a relative contraindication to laparoscopic surgery. However, studies have demonstrated the advantages of laparoscopic surgery over an open radical approach; hence, previous abdominal surgery is no longer viewed as a contraindication. Here, we describe the case of a 62-year-old man who presented with an incidental finding of right renal cell carcinoma (RCC). We performed a radical nephrectomy on this patient who had undergone multiple previous abdominal surgeries. During this procedure, a small bowel injury occurred. Herein, we review the available evidence and describe the risk factors and techniques to avoid injury from laparoscopic port-site placement in patients undergoing nephrectomy with a history of previous abdominal surgery.

Classification of positive surgical margins and tumor recurrence after nephron-sparing surgery for small renal masses

BACKGROUND

The association of positive margin and local recurrence after nephron-sparing surgery (NSS) remains a notably controversial issue. The aim of the present study was to investigate the relationship between classification of positive surgical margins (PSMs) and tumor recurrence based pathological findings.

METHODS

Clinical, pathological, and follow-up data of 600 small renal cancer patients who underwent NSS between November 2007 and November 2017 at four hospitals in China were analyzed retrospectively.

RESULTS

Of the 600 reviewed patients, 20 had positive margins. During the follow-up period of 56 months, only three cases of tumor recurrence were identified. Pathological examination was performed, and subsequently a new classification criteria were proposed: 1) False PSMs, which could be further divided into three subtypes: i) no standard processing performed on pathological specimens (seven patients); ii) incidental incision into the tumor during operation, with the tumor bed free of tumor residues (four patients); iii) part of the tumor pseudocapsule was noted to be remained in the tumor bed, with no signs of tumor residue (four patients). 2) True PSMs with two subtypes: i) a large number of residual tumor cells at the surgical margin (three patients); ii) incision of satellite tumor nodules detected around a large tumor (two patients).

CONCLUSION

Taken together, PSMs in NSS were rarely found. Based on the pathological examination findings, PSMs can be divided into false positive and true positive. This being said, PSMs were determined to be poor predictors for local recurrence, with no predominant association with true tumor remnants in the majority of our evaluated cases. Through the key findings of our study, we concluded that PSMs should be carefully analyzed and treated on a case-by-case basis.

A Multi-Institutional Propensity Score Matched Comparison of Transperitoneal and Retroperitoneal Partial Nephrectomy for cT1 Posterior Tumors

OBJECTIVE

To compare the perioperative and renal functional outcome between transperitoneal and retroperitoneal robotic partial nephrectomy (TP-RPN and RP-RPN) in the largest cohort to date of RP-RPN for posterior tumors.

METHODS

We identified 519 patients who met eligibility criteria and underwent TP-RPN (n = 357, 68.8%) or RP-RPN (n = 162, 31.2%) for a posteriorly located cT1 tumor. Patients were propensity score (PS) matched on preoperative and tumor-specific characteristics. Perioperative outcome and renal function outcome at median follow-up 22 months were compared.

RESULTS

Between the PS matched TP-RPN (n = 157, 50%) and RP-RPN (n = 157, 50%) patients, operative time (OT) (185.0 versus 157.0, P < .001) was longer in TP-RPN versus RP-RPN patients. No significant differences in ischemia time (P = .618), blood loss (P = .178), positive surgical margins (P = .501), overall postoperative complications (P = .861), or progression of chronic kidney disease stage at median 22 months (P = .599) were identified. Length of stay (LOS) was reduced in RP-RPN patients (P = .017), but was not different once an institution used a postoperative day (POD)-1 discharge protocol (P = .579). Operative times were similar between groups in patients with obesity (P = .293) or a cT1b renal mass (P = 908).

CONCLUSION

RP-RPN for posterior tumors resulted in reduced OT and a shorter LOS compared to TP-RPN. When surgeons aimed to routinely discharge patients on POD-1, the surgical approach did not influence LOS. Operative time was similar between RP and TP-RPN among patients with obesity or a cT1b renal mass. All other measures, including ischemia time, blood loss, margin rates, complications, and renal function, did not differ between the two approaches.

Laparoscopic partial nephrectomy: Comparative study of the transperitoneal pathway and the retroperitoneal pathway

INTRODUCTION

Laparoscopic partial nephrectomy is the recommended treatment for tumours smaller than 4cm in cases where it is feasible. Depending on the location of the tumour, the transabdominal or direct retroperitoneal pathway may be considered.

OBJECTIVE

To compare the transperitoneal (TPPN) and direct retroperitoneal (RPPN) partial nephrectomies performed between 2007 and 2016.

MATERIAL AND METHODS

A retrospective study was conducted on 71 patients who underwent TPPN (42) or direct RPPN (29) partial nephrectomy. We evaluated the characteristics of the patients and tumours, including tumour complexity (PADUA, RENAL, C-index). We compared perioperational variables, including the complications between the 2 pathways.

RESULTS

We found no differences in terms of age, sex, Charlson's score and BMI. A larger proportion of patients in the direct RPPN group had prior major abdominal surgery (7.1 vs. 24.1%; P=.043). There were no differences in tumour size, laterality, polarity or complexity in any of the assessed scores. There were significant differences in tumour location (anterior/middle/posterior) between the TPPN and RPPN groups (54.8/31/14.3 vs. 3.4/13.8/82.8%; P<.001). There were no differences in the surgical time or length of stay. The TPPN group had a smaller urinary tract opening (4.8 vs. 27.6%; P=.007) and a higher percentage of haemostatic renorrhaphy (47.6 vs. 17.2%; P=.008). There were no differences in the need for warm ischaemia, in the changes in haemoglobin levels or in the glomerular filtration rate. The complication rates were similar for the two series.

CONCLUSION

The two pathways show similar results in terms of renal function preservation, complications and oncological results. However, we recommend understanding both techniques and adapting the access type to the clinical case.

Complications of Renal Surgery

The incidence of the small renal mass continues to increase owing to the aging population and the ubiquity imaging. Most of these tumors are stage I tumors. Management strategies include surveillance, ablation, and extirpation. There is a wide body of literature favoring nephron-sparing approaches. Although nephron-sparing surgery may yield decreased long-term morbidity, it is not without its drawbacks, including a higher rate of complications. Urologists must be attuned to the complications of surgery and develop strategies to minimize risk. This article reviews expected complications of surgery on renal masses and risk stratification schema.

WITHDRAWN: Surgical management of localised renal cell carcinoma

This review is being updated and replaced following the publication of a protocol (Krabbe L‐M, Kunath F, Schmidt S, Miernik A, Cleves A, Walther M, Kroeger N. Partial nephrectomy versus radical nephrectomy for clinically localized renal masses [Protocol]. Cochrane Database of Systematic Reviews 2016, Issue 2. Art. No.: CD012045. DOI: 10.1002/14651858.CD012045) for a new review with a narrower scope. It will remain withdrawn when the new review is published.

The editorial group responsible for this previously published document have withdrawn it from publication.

Off-Clamp Renal Tumourectomy by Retroperitoneoscopy in Posterior Renal Tumours of Medium Complexity (Padua score 8-9)

BACKGROUND

The guidelines recommend partial surgery for T1 renal tumours. Various aspects of this surgery have evolved in recent years, including the clamping method and duration, enucleation, the retroperitoneoscopic approach and the use of 3mm ports. We present our initial series on laparoscopic renal tumourectomy by retroperitoneoscopy (LRTR) and analyse our learning curve and use of 3-mm instrumentation.

MATERIAL AND METHODS

From January 2011 to January 2015, we performed LRTR on 50 patients with posterior or convex T1 renal tumours. After 10 cases, the technique changed to off-clamp, and 11 cases were subsequently performed with 3mm instrumentation.

RESULTS

The mean tumour size was 34.36 mm (14-62), with a mean PADUA score of 8.42 (5-12). The mean operative time was 163.1 minutes (75-300), and the mean warm ischaemia time was 4.21 minutes (0-28). The main renal artery was not clamped in 41 (82%) patients, and no vessel (zero ischaemia) was clamped in 39 (78%) patients. Seven cases had positive margins (6 focal). Eleven LRTRs were performed with 3mm instrumentation, with shorter surgical times, less intraoperative bleeding and shorter hospital stays.

CONCLUSIONS

Retroperitoneoscopy coupled with enucleation enables the extirpation without clamping of posterior renal tumours, with a relatively short learning curve. The 3-mm material enables the technique to be performed, although in our experience it has resulted in a higher rate of positive surgical margins.

Retroperitoneal Robot-Assisted Partial Nephrectomy for Posterior Renal Masses Is Associated with Earlier Hospital Discharge: A Single-Institution Retrospective Comparison

PURPOSE

To compare perioperative outcomes, specifically hospital length of stay (LOS), after retroperitoneal and conventional transperitoneal robot-assisted partial nephrectomy (RAPN).

PATIENTS AND METHODS

We retrospectively compared consecutive patients with a posterior renal mass undergoing retroperitoneal RAPN (n=116) versus transperitoneal RAPN (n=97) at our institution between July 2007 and March 2014. The surgical approach was based on patient and tumor characteristics, history of abdominal surgery, and surgeon preference. The primary outcome was postoperative LOS, and secondary outcomes included complication rate, inpatient narcotic pain medication use, and inpatient antiemetic use.

RESULTS

Baseline patient and tumor characteristics were similar between groups. A significantly great proportion of patients undergoing retroperitoneal RAPN had LOS equal to 1 day (57% vs 10%, P<0.01). Complication rates were similar between groups (P=0.37). Median pain medication use was also similar between groups (P=0.85). A significantly greater proportion of retroperitoneal RAPN patients, however, needed no antiemetics postoperatively (59% vs 43%, P=0.02). On multivariate analysis, transperitoneal RAPN was a significant predictor of LOS greater than 1 day (odds ratio=7.4, P<0.01), when controlling for age, sex, body mass index, patient comorbidity, previous abdominal surgery, baseline kidney function, nephrometry score, and tumor size.

CONCLUSIONS

For patients with posterior renal masses, retroperitoneal RAPN significantly reduces their hospital LOS when compared with transperitoneal RAPN.

Transperitoneal versus retroperitoneal robotic partial nephrectomy: matched-pair comparisons by nephrometry scores

PURPOSE

The purpose of this study was to compare perioperative outcomes of transperitoneal (TP) and retroperitoneal (RP) robot-assisted partial nephrectomy (RPN) by matched analysis using nephrometry systems.

METHODS

A total of 107 patients who underwent RPN by a single surgeon from December 2008 to June 2012 were analyzed; 57 patients underwent TP RPN and 50 patients underwent RP RPN. Baseline demographic characteristics, perioperative outcomes and changes in renal function were collected by retrospective review of medical records. Matched-pair comparisons were done using RENAL score and C-index.

RESULTS

No significant difference was observed between TP and RP RPN in patient age, body mass index, gender, laterality, clinical stage, tumor size, RENAL score or ASA score. The TP RPN had more cystic renal masses (TP vs. RP = 33 vs. 12 %, p = 0.012) and RP RPN had shorter median operation times (150 vs. 120 min, p = 0.015) and shorter mean warm ischemic times (26.2 vs. 22.6 min, p = 0.040) than TP RPN. In the matched-pair analysis, RP RPN showed shorter operation times with similar warm ischemic times. Estimated blood loss and visual analog pain scales showed no significant differences between groups. A total of 12 (11.4 %) postoperative complications occurred, all Clavien class I or II with no significant difference in incidence.

CONCLUSIONS

Retroperitoneal robot-assisted partial nephrectomy showed shorter operation time and generally equivalent perioperative results to TP RPN. RP RPN is a viable treatment option for treating posterior or lateral renal masses.

[Positive surgical margins in nephron sparing surgery for renal cell carcinoma]

Nephron sparing surgery (NSS) with a minimal tumor-free margin is considered the cornerstone in the contemporary management of renal cell carcinoma (RCC) stage T1. The aim of this study is to review incidence, predictive risk factors, clinical significance and oncologic outcomes of positive surgical margins (PSM) in NSS. English articles published before March 2014 have been searched in Medline Databank.PSM are present in 0-7% of patients in all surgical approaches considered. Some predictive factors,such as tumor size, localization, and histology have been identified in the past. Other topics concerning surgical technique and approach are discussed.The majority of patients with PSM do not experience disease recurrence and PSM impact on overall survival and cancer-specific survival seems to be irrelevant. These results lead to more conservative clinical strategies. However, an active surveillance is mandatory for all patients with PSM and especially for those with high risk disease. Generalization of these results is limited by the low level of evidence of available studies. Further efforts are necessary to avoid PSM intraoperatively and to provide prospective information in order to standardize the postoperative management.

Transperitoneal approach versus retroperitoneal approach: a meta-analysis of laparoscopic partial nephrectomy for renal cell carcinoma

OBJECTIVE

To compare the efficiency and safety of the transperitoneal approaches with retroperitoneal approaches in laparoscopic partial nephrectomy for renal cell carcinoma and provide evidence-based medicine support for clinical treatment.

METHODS

A systematic computer search of PUBMED, EMBASE, and the Cochrane Library was executed to identify retrospective observational and prospective randomized controlled trials studies that compared the outcomes of the two approaches in laparoscopic partial nephrectomy. Two reviewers independently screened, extracted, and evaluated the included studies and executed statistical analysis by using software STATA 12.0. Outcomes of interest included perioperative and postoperative variables, surgical complications and oncological variables.

RESULTS

There were 8 studies assessed transperitoneal laparoscopic partial nephrectomy (TLPN) versus retroperitoneal laparoscopic partial nephrectomy (RLPN) were included. RLPN had a shorter operating time (SMD = 1.001,95%confidence interval[CI] 0.609-1.393,P<0.001), a lower estimated blood loss (SMD = 0.403,95%CI 0.015-0.791,P = 0.042) and a shorter length of hospital stay (WMD = 0.936 DAYS,95%CI 0.609-1.263,P<0.001) than TLPN. There were no significant differences between the transperitoneal and retroperitoneal approaches in other outcomes of interest.

CONCLUSIONS

This meta-analysis indicates that, in appropriately selected patients, especially patients with intraperitoneal procedures history or posteriorly located renal tumors, the RLPN can shorten the operation time, reduce the estimated blood loss and shorten the length of hospital stay. RLPN may be equally safe and be faster compared with the TLPN.

Robotic retroperitoneal surgery: a contemporary review

PURPOSE OF REVIEW

Robotic-assisted renal surgery is being increasingly utilized for various kidney diseases; however, the majority of these are performed via a transperitoneal approach. Retroperitoneal robotic surgery is a relatively new technique, which allows direct access to the posterolateral surface of the kidney, as well as posterior hilar structures. In this review, we summarize the most recent publications and review our experience of retroperitoneal robotic surgery.

RECENT FINDINGS

Retroperitoneal robotic surgery has been successfully applied to radical nephrectomy, partial nephrectomy and pyeloplasty. The current series, although few, find this approach ideal for posterior and lateral renal masses, and technically feasible with the advances in robotic technology. The retroperitoneal approach has been shown to decrease operative times, narcotic need and permit quicker return of bowel function. Furthermore, there does not appear to be any increase in perioperative complications using this approach.

SUMMARY

The limited data using this technique offer an encouraging outlook on robotic retroperitoneal surgery. The retroperitoneal approach permits direct access to the renal hilum, no need for bowel mobilization and excellent visualization for posteriorly located renal disease.

Robotic retroperitoneal partial nephrectomy

PURPOSE OF REVIEW

Robotic-assisted renal surgery is being increasingly utilized; however, the majority of these are performed via a transperitoneal approach. Retroperitoneal robotic surgery is a relatively new technique allowing direct access to the posterolateral surface of the kidney, as well as posterior hilar structures. In this review, we summarize the most recent publications and review our experience of robotic retroperitoneal partial nephrectomy.

RECENT FINDINGS

The retroperitoneal approach has been successfully applied to robotic partial nephrectomy. The current series find this approach ideal for posterior and lateral renal masses, and technically feasible with the advances in robotic technology. The retroperitoneal approach has been shown to decrease operative times, narcotic need, and permit quicker return of bowel function. Furthermore, there does not appear to be any increase in perioperative complications using this approach. Since 2006, we have treated 68 patients using this approach. The mean age was 58.9 years, and mean preoperative tumor size 2.5 cm (range 1-5 cm). Mean operative and warm ischemia time were 125 min and 20.7 min, respectively. The majority of patients had renal cell carcinoma, with a 4.4% positive margin rate. The most common complication was an arterial pseudoaneurysm in 3 (4.4%) patients. The limited data using this technique offer an encouraging outlook on robotic retroperitoneal partial nephrectomy. The retroperitoneal approach permits direct access to the renal hilum, no need for bowel mobilization, and excellent visualization for posteriorly located renal masses.

Comparison of transperitoneal and retroperitoneal laparoscopic nephrectomy for renal cell carcinoma: a systematic review and meta-analysis

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Laparoscopic nephrectomy is now considered to be the reference procedure for kidney cancer. It can be performed via a transperitoneal or retroperitoneal approach. Each approach has its advantages and disadvantages. No definitive conclusions regarding objective difference between the two approaches have been reached to date. This meta-analysis indicates that in appropriately selected patients, especially patients with posteriorly located renal tumors, the retroperitoneal approach may be faster and equally safe compared with the transperitoneal approach.

OBJECTIVE

To evaluate the efficiency and safety of the retroperitoneal and transperitoneal approaches in laparoscopic radical/partial nephrectomy (RN/PN) for renal cell carcinoma.

METHODS

A systematic search of PUBMED, EMBASE, and the Cochrane Library was performed to identify prospective randomized controlled trials and retrospective observational studies that compared the outcomes of the two approaches. Outcomes of interest included perioperative and postoperative variables, surgical complications and oncological variables.

RESULTS

Twelve studies assessing transperitoneal laparoscopic RN (TLRN) vs retroperitoneal laparoscopic RN (RLRN) and six studies assessing transperitoneal laparoscopic PN (TLPN) vs retroperitoneal laparoscopic PN (RLPN) were included. The RLRN approach had a shorter time to renal artery control (weighted mean difference [WMD] 68.65 min; 95% confidence interval [CI] 40.80-96.50; P < 0.001) and a lower overall complication rate (odds ratio 2.12; 95% CI 1.30-3.47; P = 0.003) than TLRN. RLPN had a shorter operating time (WMD 48.85 min; 95% CI 29.33-68.37; P < 0.001) and a shorter length of hospital stay (WMD 1.01 days; 95% CI 0.39-1.63; P = 0.001) than TLPN. There were no significant differences between the retroperitoneal and transperitoneal approaches in other outcomes of interest.

CONCLUSIONS

This meta-analysis indicates that, in appropriately selected patients, especially patients with posteriorly located renal tumours, the retroperitoneal approach may be faster and equally safe compared with the transperitoneal approach. Despite our rigorous methodology, conclusions drawn from our pooled results should be interpreted with caution because of the inherent limitations of the included studies.

Positive surgical margins after nephron-sparing surgery

CONTEXT

Little is known on the natural history of positive surgical margins (PSMs) in partial nephrectomy (PN). Accumulating data suggest that secondary nephrectomy might not be necessary in all patients with PSMs after PN.

OBJECTIVE

Provide an overview on incidence and risk factors for PSMs after partial nephrectomy and on the rate of local and distant disease recurrence related to PSMs. We also provide recommendations on how to avoid and how to treat PSMs after PN.

EVIDENCE ACQUISITION

A nonsystematic literature research was based on Medline, Scopus, and Web of Science queries on these keywords: nephron-sparing surgery, partial nephrectomy/ies, and margin. Only human studies (original research) published in English were included.

EVIDENCE SYNTHESIS

PSMs are present in 0-7% of patients after open PN, in 0.7-4% after laparoscopic PN, and in 3.9-5.7% after robot-assisted PN. The thickness of healthy parenchyma surrounding the tumour is irrelevant as long as complete tumour removal is achieved. The coincidence of a highly malignant tumour and PSM increases the risk of local recurrence. Intermediate follow-up data indicate that the vast majority of patients with PSMs will not experience local or distant tumour recurrence. Frozen-section analysis for evaluation of resection margins during PN is of minor clinical significance, as the surgeon's gross assessment of macroscopically negative margins provides reliable results.

CONCLUSIONS

PSMs in PN are rare. As indicated by intermediate follow-up data, the majority of patients with PSMs after PN remain without disease recurrence, and a surveillance strategy seems preferable to surgical reintervention.

Laparoscopic partial nephrectomy: a matched-pair comparison of the transperitoneal versus the retroperitoneal approach

OBJECTIVES

To compare surgical and functional results of both surgical approaches to endoscopic partial nephrectomy. It is currently performed either by the transperitoneal (t) or the retroperitoneal (r) approach.

METHODS

This was a retrospective, matched-pair comparison of 105 patients who underwent either transperitoneal laparoscopic (Graz) or retroperitoneoscopic (Klagenfurt) partial nephrectomy for clinical T1a renal masses.

RESULTS

A total of 35 patients after transperitoneal laparoscopic and 70 patients after retroperitoneoscopic partial nephrectomy were included to this analysis after matching for age (T: 59.3 vs R: 60.1 a), preoperative glomerular filtration rate (GFR) (T: 93.2 vs R: 96.1 mL/min) and tumor size (T: 2.4 vs R: 2.5 cm). Nephrometry scores were comparable between groups and were low, medium, and high in 54.3%, 45.7%, and 0% (t) and 55.7%, 42.9%, and 1.4% (r) of patients (P = .9). Operative time (T: 139.3 minutes vs. R: 83.9 minutes; P < .001) and hospitalization (T: 7 days, R: 5 days; P < .001) were shorter in the retroperitoneoscopic group. Ischemia time (T: 24.3 minutes, R: 22.6 minutes) and postsurgical GFR (T: 86.6 vs R: 90.0 mL/min), postsurgical GFR-decrease (T: 7.1%, R: 6.2%, P = .9) and decline of hemoglobin (T: 17.1%, R: 16.6%) were comparable. Complications were 4 nephrectomies (T: n = 1, R: n = 3), 2 revisions for hemorrhage (R: n = 2), 4 pneumothorax (R: n = 4), and 2 urinary fistulas (T: n = 2). The positive surgical margin rate was comparable between groups (T: n = 3, R: n = 5).

CONCLUSIONS

Transperitoneal laparoscopic and retroperitoneoscopic partial nephrectomy provide comparable surgical and functional results. One advantage of the retroperitoneoscopic access seems to be a shorter total surgical time.

Retroperitoneal laparoscopic upper-pole nephroureterectomy for duplex kidney anomalies in adult patients

OBJECTIVES

To present our surgical techniques and experience with retroperitoneal laparoscopic upper pole nephroureterectomy for a duplex kidney in adult patients without vesicoureteral reflux.

METHODS

A total of 32 adult patients with a duplex kidney underwent laparoscopic upper pole nephroureterectomy. A 3-port, finger- and balloon-dissecting, retroperitoneal approach was used. The upper pole renal parenchyma was divided circumferentially between the upper and lower poles using a harmonic scalpel, maintaining a margin around the upper pole parenchyma to avoid any possible injury to the lower pole functioning moiety. The urothelium of the remnant upper pole parenchyma was stripped off, and the edges of the remnant upper pole parenchyma were approximated with figure-of-8 stitches. The distal upper pole ureter was mobilized and transected at the point at which the ureter crossed anterior to the iliac vessels. Intravenous urography and renal ultrasonography were performed at 3 and 6 months postoperatively.

RESULTS

All laparoscopic operations were performed successfully without conversion to open surgery. The mean operative time was 83 minutes. The mean blood loss was 18 mL. The mean postoperative hospital stay was 7 days. No intraoperative or major postoperative complications occurred. The intravenous urography and renal ultrasound findings 3 and 6 months postoperatively demonstrated normal pyelography findings and renal function of the preserved lower pole in all patients.

CONCLUSIONS

Retroperitoneal laparoscopic upper pole nephroureterectomy is a safe and effective procedure and an excellent minimally invasive treatment option for the adult patient with a duplex kidney.

Laparoscopic ureterolithotomy as a primary modality for large proximal ureteral calculi: comparison to rigid ureteroscopic pneumatic lithotripsy

OBJECTIVE

To define the role of laparoscopic ureterolithotomy (LU) as a primary modality for large proximal ureteral stones, we compared the outcomes of primary LU with those of ureterorenoscopy (URS), the currently established modality in this circumstance.

MATERIALS AND METHODS

Among 71 patients who underwent LU in our institution between February 2005 and January 2010, 32 patients with stone size over 1.5 cm who underwent LU as a primary modality without prior shockwave lithotripsy or URS and for whom LU was conducted as a separate procedure were exclusively enrolled. Based on preoperative characteristics of patients and stones, this patient group was matched with the URS group (n = 32, rigid pneumatic lithotripter) during the same period.

RESULTS

The LU group and the URS group were similar in age, gender distribution, body mass index, stone size (18.1 ± 4.2 versus 17.9 ± 3.6 mm; P = .88), and stone location. Members of the LU group required a longer operative time (118 ± 53 versus 59 ± 41 minutes; P < .001) and hospital stay (5.9 ± 2.1 versus 3.4 ± 2.4 days; P < .001) and had greater blood loss (155 ± 62 mL). However, stone clearance rate (no remnant stone in postoperative X-ray of the kidney, ureter, and bladder) in a single session was marginally higher in the LU group (93.8% versus 68.8%; P = .06). Total complication rate was not significant and was slightly higher in the URS group (12.5% versus 21.9%, P = .51). Stone migration into the kidney (n = 2 versus 5), ureteral perforation (n = 0 versus 3), open conversion (n = 1 versus 2), and ureteral stricture (n = 1 versus 2), as long-term complications, occurred more frequently in the URS group.

CONCLUSIONS

For large proximal ureteral stones, LU can be conducted safely as a first-line procedure without increase of complication rate, compared with conventional URS. Although LU required a prolonged operative time and a longer hospital stay and blood loss was greater, our data showed an advantage of LU in high clearance rate in a single procedure.

Surgical management of localised renal cell carcinoma

BACKGROUND

Surgical excision remains the core to the management of localised renal cancer and several studies have evaluated the safety and clinical effectiveness of laparoscopic surgery and other recently introduced interventions for the localised disease.

OBJECTIVES

To identify and review the evidence from randomised trials comparing different surgical interventions in localised renal cell carcinoma.

SEARCH STRATEGY

Randomised or quasi randomised trials comparing various surgical interventions in the management of adults with surgically resectable localised renal cancer. RCTs were identified by searching The Cochrane Central Register of Controlled Trials (CENTRAL, Issue 3, 2009), MEDLINE (Silver Platter, from 1966 to August 2009), EMBASE via Ovid (from 1980 to August 2009), and a number of other data bases.

SELECTION CRITERIA

Studies were assessed for eligibility and quality, and data from published trials were extracted by two reviewers.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

No randomised trials were identified meeting the inclusion criteria reporting on the comparison between open radical nephrectomy with laparoscopic approach or new modalities of treatment such as radiofrequency or cryoablation. Three randomised controlled trials compared the different laparoscopic approaches to nephrectomy (transperitoneal versus retroperitoneal) and found no statistical difference in operative or perioperative outcomes between the two treatment groups. There were several non-randomised and retrospective case series reporting various advantages of laparoscopic renal cancer surgery such as less blood loss, early recovery and shorter hospital stay

AUTHORS' CONCLUSIONS

The main source of evidence for the current practice of laparoscopic excision of renal cancer is drawn from case series, small retrospective studies and very few small randomised controlled trials. The results and conclusions of these studies must therefore be interpreted with caution.

Experience and learning curve of retroperitoneal laparoscopic ureterolithotomy for upper ureteral calculi

PURPOSE

To summarize our experience and evaluate the learning curve of retroperitoneal laparoscopic ureterolithotomy of the upper ureter.

PATIENTS AND METHODS

Between May 2004 and May 2007, 40 patients underwent retroperitoneal laparoscopic ureterolithotomy of the upper ureter. We divided the first and last 20 patients into group I and group II. There was no statistical difference in stone size between groups. Operative time and complications were measured as a basis for the assessment of the learning curve.

RESULTS

In group I, the complication rate was 15% (3/20), including two patients whose procedure was converted to open surgery because of intraoperative bleeding, and one patient who experienced urine leakage because of a displaced Double-J ureteral stent. In group II, no postoperative complications occurred, while the mean operative time was significantly shorter compared with the earlier operations (65 vs 120 min).

CONCLUSION

Retroperitoneal laparoscopic ureterolithotomy is safe and effective for large or impacted stones of the upper ureter. It is associated with a short learning curve in the setting of an active laparoscopic practice for selected patients.

[Role of laparoscopy in the presence of a renal mass under 4 cm in size]

The increasingly common incidental diagnosis of small renal masses (SRMs) (measuring under 4 cm in size) has led to the consideration of applying minimally invasive techniques to deal with them--particularly in view of the high percentage of non-malignant conditions of this size that are radiologically indistinguishable from tumor lesions. Accordingly, laparoscopic access has gained great importance in the management of these masses, in an attempt to lessen the morbidity associated with lumbotomy. Laparoscopic partial nephrectomy (LPN) is an evolving technique in most centers; on one hand it competes with open partial nephrectomy as the technique of choice, and on the other it will compete in the future with the non-excisional management techniques. These latter procedures in turn have become more precise thanks to laparoscopy. Based on a standardized review of the abundant literature on the treatment of SRMs, the present study examines the technical innovations and improvements afforded by the laparoscopic approach, not only for excision purposes but also a vehicle for minimally invasive treatments. Likewise, the requirements of Services of Urology and the improvements that could be introduced in health systems for advancing the application of LPN in the management of SRMs are commented. Progressive fine-tuning of the technique, with improvement of the laparoscopic repertoire and availability of hemostatic agents, will contribute to increase the indications for LPN in the future. The limited frequency of the disorder and the need to optimize the technique will require health care supervisors to centralize this type of pathology in centers with experience in laparoscopy and open partial nephrectomy.