Transperitoneal Robot-Assisted Partial Nephrectomy: A Comparison of Posterior and Anterior Renal Masses

Robot-assisted partial nephrectomy for renal cell carcinoma in the isthmus of horseshoe kidney

The anatomic features of a horseshoe kidney are unique—the kidney is fixed and poorly mobile, with many arterial and venous blood supplies, thereby complicating minimally invasive surgery for renal cancer in this setting. Several reports have described robot-assisted partial nephrectomy (RAPN) to treat renal cancer in a horseshoe kidney, but no reports of RAPN for renal cancer in the isthmus of a horseshoe kidney have been published to date. This case report describes the technique and usefulness of RAPN for treatment of renal cancer located in the isthmus of a horseshoe kidney.

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Robot-assisted partial nephrectomy for a horseshoe kidney is technically difficult.

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The problem is poor kidney mobility and complex blood vessels.

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This describes the technique and the benefit of RAPN for a tumor in the isthmus.

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The key is to create an appropriate and safe surgical view for each scene.

Nephrometry scores: a validation of three systems for peri-operative outcomes in retroperitoneal robot-assisted partial nephrectomy

OBJECTIVE

To externally validate the RENAL, PADUA and SPARE nephrometry scoring systems for use in retroperitoneal robot-assisted partial nephrectomy (RAPN).

MATERIALS AND METHODS

Nephrometry scores were calculated for 322 consecutive patients receiving retroperitoneal RAPN at a tertiary referral centre from 2017. Patients with multiple tumours were excluded. Scores were correlated with peri-operative outcomes, including the trifecta (warm ischaemia time <25 min, no peri-operative complications and a negative surgical margin), both as continuous and categorical variables. Comparisons were performed using Spearman correlation and ability to predict the trifecta was assessed using binomial logistical regression.

RESULTS

All three scoring systems correlated significantly with the main variables (operating time, warm ischaemia time and estimated blood loss), both as continuous and categorical variables. Only PADUA and SPARE were able to predict achievement of the trifecta (PADUA area under the curve [AUC] 0.623, 95% confidence interval [CI] 0.559-0.668; SPARE AUC 0.612, 95% CI 0.548-0.677).

CONCLUSION

This study validates the RENAL, PADUA and SPARE scoring systems to predict key intra-operative outcomes in retroperitoneal RAPN. Only PADUA and SPARE were able to predict achievement of the trifecta. As a simplified version of the PADUA scoring system with comparable outcomes, we recommend using the SPARE system.

Comparison of Kidney Function in the Early Postoperative Period in Transperitoneal Robot-Assisted Laparoscopic Partial Nephrectomy Between Anterior and Posterior Renal Tumors: A Propensity Score-Matched Study

OBJECTIVE

To compare early postoperative renal function in transperitoneal robot-assisted laparoscopic partial nephrectomy (RAPN) for anterior and posterior renal tumors.

PATIENTS AND METHODS

This study included 227 patients who underwent transperitoneal RAPN for anterior or posterior renal tumors. Tumor position was defined by RENAL nephrometry score. To minimize selection bias between anterior and posterior tumors, patient variables were adjusted using 1:1 propensity score matching.

RESULTS

Of the 227 patients, 125 were classified as having anterior tumors and 102 as having posterior tumors. After matching, 82 patients were included in each group. The mean preoperative estimated glomerular filtration rate (eGFR) was 66 mL/min/1.73 m². The mean tumor size was 28 to 29 mm. The decrease in early postoperative nadir eGFR (-10% vs -4.0%, p = 0.0103) was significantly higher for posterior tumors than for anterior tumors. However, the difference improved 6 to 12 months after surgery (-6.0% vs -6.2%, p = 0.9564). The other surgical outcomes, including operative time, warm ischemia time (WIT), complications, surgical margin status, and length of hospital stay, were not significantly different between the two groups. In multivariate analysis of the entire cohort, posterior tumors (vs anterior tumor, odds ratio [OR]: 2.30, p = 0.0051), longer WIT (OR: 3.10, p = 0.0019), and high tumor complexity (vs low complexity, OR: 3.46, p = 0.0264) were independent predictors for development of a 10% decrease in early postoperative eGFR.

CONCLUSIONS

Posterior tumors had a greater decrease in early postoperative nadir eGFR than anterior tumors, with equivalent surgical outcomes, including similar renal function, 6 to 12 months after surgery in the setting of transperitoneal RAPN.

Robotic Partial Nephrectomy for Posterior Tumors Through a Retroperitoneal Approach Offers Decreased Length of Stay Compared with the Transperitoneal Approach: A Propensity-Matched Analysis

INTRODUCTION

We sought to compare surgical outcomes between transperitoneal and retroperitoneal robotic partial nephrectomy (RPN) for posterior tumors.

PATIENTS AND METHODS

Using our multi-institutional RPN database, we reviewed 610 consecutive cases for posterior renal masses treated between 2007 and 2015. Primary outcomes were complications, operative time, length of stay (LOS), surgical margin status, and estimated glomerular filtration rate (eGFR) preservation. Secondary outcomes were estimated blood loss, warm ischemia time (WIT), disease recurrence, and disease-specific mortality. Due to significant differences in treatment year and tumor size between approaches, retroperitoneal cases were matched 1:4 to transperitoneal cases based on propensity scores using the greedy algorithm. Outcomes were compared between approaches using the chi-square and Mann-Whitney U tests.

RESULTS

After matching, 296 transperitoneal and 74 retroperitoneal cases were available for analysis, and matched groups were well balanced in terms of treatment year, age, gender, race, American Society of Anesthesiologists physical status classification (ASA) score, body mass index, tumor laterality, tumor size, R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to the collecting system or sinus, anterior/posterior, location relative to polar lines) score, and hilar location. Compared with transperitoneal, the retroperitoneal approach was associated with significantly shorter mean LOS (2.2 vs 2.6 days, p = 0.01), but longer mean WIT (21 vs 19 minutes, p = 0.01). Intraoperative (p = 0.35) and postoperative complications (p = 0.65), operative time (p = 0.93), positive margins (p = 1.0), and latest eGFR preservation (p = 0.25) were not significantly different between approaches. No differences were detected in the other outcomes.

CONCLUSIONS

Among high-volume surgeons, transperitoneal and retroperitoneal RPN achieved similar outcomes for posterior renal masses, although with slight differences in LOS and WIT. Retroperitoneal RPN may be an effective option for the treatment of certain small posterior renal masses.

Outcomes of partial nephrectomy in patients who meet percutaneous ablation criteria

INTRODUCTION

Treatment options for small renal masses include partial nephrectomy (PN), ablation and active surveillance. We sought to compare patients who met the criteria for percutaneous ablation but underwent robotic PN to the rest of our robotic PN cohort. This was done in order to detect any safety concerns and to define any risk factors that might contraindicate the use of robotic PN, an oncologically superior procedure, in patients who qualify for ablation.

MATERIAL AND METHODS

Our departmental renal mass registry was queried for patients who underwent robotic PN but also met criteria for percutaneous ablation. These were compared to the rest of the robotic PN cohort. Demographics, perioperative characteristics and recurrence data were compared.

RESULTS

Overall, 321 robotic PNs were identified. Of these, 26 (8.1%) met ablation criteria. Among patient characteristics, age and BMI were similar in both groups. Among operative characteristics, estimated blood loss (EBL) and operative time were similar. Warm ischemia time was significantly less for patients who met ablation criteria (14 vs. 17 minutes, p = 0.002). Mean tumor size was smaller for patients who met ablation criteria (2.3 vs. 2.7 cm, p = 0.012). Among postoperative characteristics, complications were similar overall and when present, stratified by Clavien grade.

CONCLUSIONS

Robotic PN is a safe, effective treatment option for small renal masses, even in patients who meet ablation criteria. There were no recurrences in our cohort and the majority of complications were Clavien grade 1.