Laparoscopic partial nephrectomy for endophytic hilar tumors: feasibility and outcomes

Partial Nephrectomy Versus Radical Nephrectomy for Endophytic Renal Tumors: Comparison of Operative, Functional, and Oncological Outcomes by Propensity Score Matching Analysis

Purpose

The study aimed to compare operative, functional, and oncological outcomes between partial nephrectomy (PN) and radical nephrectomy (RN) for entophytic renal tumors (ERTs) by propensity score matching (PSM) analysis.

Methods

A total of 228 patients with ERTs who underwent PN or RN between August 2014 and December 2021 were assessed. A PSM in a 1:1 ratio was conducted to balance the differences between groups. Perioperative characteristics, renal functional, and oncological outcomes were compared between groups. Univariate and multivariate logistic and Cox proportional hazard regression analyses were used to determine the predictors of functional and survival outcomes.

Results

After PSM, 136 cases were matched to the PN group (n = 68) and the RN group (n = 68). Patients who underwent RN had shorter OT, less EBL, and lower high-grade complications (all p <0.05) relative to those who underwent PN. However, better perseveration of renal function was observed in the PN group, which was reflected in 48-h postoperative AKI (44.1% vs. 70.6%, p = 0.002), 1-year postoperative 90% eGFR preservation (45.6% vs. 22.1%, p = 0.004), and new-onset CKD Stage ≥III at last follow-up (2.9% vs. 29.4%, p <0.001). RN was the independent factor of short-term (OR, 2.812; 95% CI, 1.369–5.778; p = 0.005) and long-term renal function decline (OR, 10.242; 95% CI, 2.175–48.240; p = 0.003). Furthermore, PN resulted in a better OS and similar PFS and CSS as compared to RN (p = 0.042, 0.15, and 0.21, respectively). RN (OR, 7.361; 95% CI, 1.143–47.423; p = 0.036) and pT3 stage (OR, 4.241; 95% CI, 1.079–16.664; p = 0.039) were independent predictors of overall mortality.

Conclusion

Among patients with ERTs, although the PN group showed a higher incidence of high-grade complications than RN, when technically feasible and with experienced surgeons, PN is recommended for better preservation of renal function, longer OS, and similar oncological outcomes.

Modified Laparoscopic Nephron-Sparing Surgery for Large Renal Hilar Angiomyolipoma: Dual-Center Experience

Objective

The aim of this study is to evaluate a potential successful strategy for treating large renal hilar angiomyolipoma (RHAML) during the procedure of laparoscopic nephron-sparing surgery (NSS).

Methods

The total study population includes 12 patients with large RHAMLs who underwent laparoscopic NSS in the Department of Urology of Fujian Provincial hospital and People’s Hospital of Zhejiang, ranging from January 2016 to March 2020. The perioperative variables, intraoperative procedures, and postprocedure complications were all recorded. Three months later, all patients returned to the hospital to check their postoperative recovery by reviewing the computed tomography urography (CTU) image. In the follow-up, patients were asked to have their review by CT or color doppler ultrasound every year.

Results

Laparoscopic NSS was successfully performed in all patients. The average operation time was 113.33 ± 33.39 min; the intraoperative blood loss was about 137.50 ± 91.17 ml; the warm ischemia time was 25.25 ± 4.88 min; the drainage tube extubation time was 4.58 ± 2.07 days; and the hospital stay time was 6.42 ± 1.78 days. The average follow-up time was 14.58 ± 9.18 months. After 3 months, all CTU images showed an unobstructed urinary tract in the patient, and no tumor recurrence was found. In addition, no patients had renal atrophy and urine extravasation during follow-up.

Conclusions

Laparoscopic NSS for RHAML is complex and technically demanding, but good surgical design and operation can achieve satisfactory surgical results. Modified laparoscopic NSS was a beneficial technique and may provide a reference for treating patients with RHAML.

The Role of Intraoperative Ultrasonography Associated with Clampless Technique in Three-Dimensional Retroperitoneoscopic Laparoscopic Enucleation of Completely Endophytic Renal Tumors

Objectives: To evaluate perioperative and functional outcomes of clampless laparoscopic tumor enucleation for completely endophytic renal tumors with the guide of intraoperative ultrasonography. Methods: We analyzed patients with clinically completely endophytic tumors, renal tumors, who underwent clampless three-dimensional (3D) retroperitoneoscopic laparoscopic tumor enucleation between January 2012 and January 2021. Patients with exophytic tumors were excluded. Intraoperative ultrasonography was used to map out the mass in all surgeries. Results: Overall, 57 patients underwent clampless 3D retroperitoneoscopic laparoscopic tumor enucleation. Mean surgical time was 131 minutes, and mean estimated blood loss was 202 mL. Mean hospital stay was 4.7 days. Major and minor postoperative complications occurred, respectively, in 3 and 10 cases. Only a patient had a positive surgical margin. One-year renal function did not differ from baseline. Conclusion: Our study showed that clampless laparoscopic enucleation guided by laparoscopic ultrasonography ensured satisfactory outcomes for completely intrarenal tumors, with excellent renal function preservation 1 year after surgery.

A Modified Two-Layer Suture Technique for Transperitoneal Laparoscopic Partial Nephrectomy: Single-Center Clinical Experience

Purposes

This study aims to evaluate the feasibility and efficacy of a modified two-layer suture method during laparoscopic partial nephrectomy (LPN) by a comparative analysis with the traditional two-layer suture.

Methods

A total of 60 LPN patients were enrolled in this study, of which 30 patients received the modified two-layer suture method and the remaining 30 patients underwent the traditional two-layer suture. Then, surgical characteristics including operative time, warm ischemic time (WIT), estimated blood loss (EBL), and glomerular filtration rate (GFR) were recorded. Finally, univariable and multivariable linear regression analyses were used to evaluate the correlations of tumor characteristics, suture methods, and postoperative renal function.

Results

There was no significant difference between the two suture groups with respect to patient and tumor characteristics, postoperative creatinine level, and blood urea nitrogen (BUN) level. The modified suture group showed a significantly shorter clamping time and a less GFR level reduction than the traditional two-layer suture group (15 vs. 23 min; 42.32 ± 9.48 vs. 27.07 ± 7.88; p < 0.05). Additionally, the modified two-layer suture was an independent factor that influenced the clamping time and the level of GFR reduction.

Conclusion

The modified two-layer suture method is feasible and effective for LPN.

Robot-assisted partial nephrectomy versus standard laparoscopic partial nephrectomy for renal hilar tumor: A prospective multi-institutional study

OBJECTIVE

To investigate whether robot-assisted partial nephrectomy compared with laparoscopic partial nephrectomy is effective for renal hilar tumor removal.

METHODS

This was a prospective, multicenter, single-arm, open-label trial with a 2-year enrollment period. A total of 22 academic hospitals in Japan participated in the present study. Comparison with historical control values from reported studies of laparoscopic partial nephrectomy was carried out. The warm ischemia time and positive surgical margin rate were set as primary perioperative and oncological outcomes. In the historical control group, these were 27.7 min and 13%, respectively.

RESULTS

The analysis population included 105 participants. The mean warm ischemia time was 20.2 (95% confidence interval 16.7-21.8; P < 0.0001 vs 27.7). Two of 103 participants (1.9%) had a positive surgical margin (95% confidence interval 0.5-6.8%). Both results satisfy the prespecified decision criteria for the superiority of robot-assisted partial nephrectomy over the historical control of laparoscopic partial nephrectomy. Resected weight and preoperative estimated glomerular filtration rate were predictive factors of functional loss of the partially nephrectomized kidney after robot-assisted partial nephrectomy.

CONCLUSION

Robot-assisted partial nephrectomy for clinical T1 renal hilar tumors results in shorter warm ischemia time than and comparable positive surgical margin rate to those reported for laparoscopic partial nephrectomy.

Comparison of Robot-Assisted and Laparoscopic Partial Nephrectomy for Completely Endophytic Renal Tumors: A High-Volume Center Experience

Objectives: To compare the perioperative, functional, and oncologic outcomes of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) for completely endophytic renal tumors (three points for the "E" element of the R.E.N.A.L. scoring system). Materials and Methods: We retrospectively reviewed patients who underwent either RAPN or LPN between 2013 and 2016. Baseline characteristics, perioperative, functional, and oncologic outcomes were compared. Univariable and multivariable logistic analyses were performed to determine factors associated with pentafecta achievement (ischemia time ≤25 minutes, negative margin, no perioperative complication, return of estimated glomerular filtration rate [eGFR] to >90% from baseline, and no chronic kidney disease upstaging). Results: No significant differences between RAPN vs LPN were noted for operating time (105 minutes vs 108 minutes, p = 0.916), estimated blood loss (50 mL vs 50 mL, p = 0.130), renal artery clamping time (20 minutes vs 20 minutes, p = 0.695), rate of positive margins (3.3% vs 2.0%, p = 1.000), and postoperative complication rates (18.0% vs 21.6%, p = 0.639). RAPN was associated with a higher direct cost ($11240 vs $5053, p < 0.001). There were no significant differences in pathology variables, rate of eGFR decline for postoperative 12-month (9.8% vs 10.6%, p = 0.901) functional follow-up. Multivariate analysis identified that only RENAL score was independently associated with the pentafecta achievement. Conclusions: For completely endophytic renal tumors, both RAPN and LPN have excellent and similar results. Both operation techniques remain viable options in the management of these cases.

Robot-assisted versus laparoscopic partial nephrectomy for anatomically complex T1b renal tumors with a RENAL nephrometry score ≥7: A propensity score-based analysis

Objectives

To present the perioperative, functional, and oncological outcomes of robot‐assisted partial nephrectomy (RPN) compared with laparoscopic partial nephrectomy (LPN) for anatomically complex T1b renal tumors with RENAL nephrometry scores ≥7.

Patients and methods

One hundred and seventy patients, during the study period, were retrospectively reviewed in our analysis according to inclusion criteria. Propensity score matching (PSM) (1:1) method was applied to impose restrictions on the potential baseline confounders. The comparisons of perioperative and functional outcomes between the RPN and LPN groups were conducted and analyzed after PSM, Kaplan‐Meier analyses were performed to assess the differences about oncological outcomes between the two groups before and after PSM.

Results

One hundred and nine and 61 T1b renal tumors with RENAL scores ≥7 were identified in the LPN and RPN groups, respectively. All significant differences in baseline characteristics disappeared after PSM. Except for 3 patients missing an appropriate pair, all the patients in the RPN group were successfully matched to 58 patients in the LPN group in a 1:1 ratio. Within the matched cohort, the RPN group was related to a significantly shorter mean operating time (OT) (P = .040), shorter mean warm ischemia time (WIT) (P = .023), and shorter median postoperative hospital stay (P = .023). The possibilities of surgical conversion, postoperative complication, and positive surgical margin were similar in the LPN and RPN groups. And there was also no significant difference in the pathological, renal functional, and oncological outcomes between the two series.

Conclusions

For patients with anatomically complex T1b renal tumors with a RENAL nephrometry score ≥7, RPN had an advantage over LPN in reducing OT, WIT, and postoperative hospital stay length without increasing the risk of complications and weakening the oncological control, while the two surgical methods were similar in renal functional preservation.

Trifecta Outcomes in Renal Hilar Tumors: A Comparison Between Robotic and Open Partial Nephrectomy

OBJECTIVES

To report a comparative analysis of outcomes in patients who underwent excisions of renal hilar tumors using both open and robotic approaches.

MATERIALS AND METHODS

We retrospectively reviewed robotic and open patients who underwent partial nephrectomy of renal hilar tumors between 2011 and 2016. "Trifecta" was defined as negative surgical margins, no complications, and a glomerular filtration rate (GFR) preservation of ≥90% at last follow-up. Inverse probability of treatment weighting (IPTW) was applied to equilibrate treatment groups, minimize selection bias, and optimize inference on the basis of each patient's clinicodemographic characteristics.

RESULTS

One hundred robotic and 64 open patients had sufficient data for IPTW. After weighting, there were no statistical differences in baseline characteristics between the two groups (p < 0.05). On adjusted analyses, robotic partial nephrectomy (RPN) achieved equivalent rates of trifecta to open surgery (21.1% vs 13.9%, respectively, p = 0.387). There were no differences between robotic and open cohorts for negative margin rates (72.8% vs 90.4%, p = 0.124), absence of complications (68.6% vs 75.2%, p = 0.587), or GFR ≥90% (39.4% vs 21.6%, p = 0.111). The robotic cohort had a shorter mean length of stay (3.8 vs 5.0 days, p = 0.012), and no difference in estimated blood loss (253.3 vs 357.1, p = 0.091) or operating time (199.8 vs 200.4, p = 0.961).

CONCLUSIONS

In our analysis both open and RPN for hilar tumors were equally likely to achieve a low "trifecta" outcome with a shorter mean length of stay in the robotic cohort.

Surgical Treatment of Completely Endophytic Renal Tumor: a Systematic Review

PURPOSE OF REVIEW

An endophytic renal tumor represents a special surgical challenge in terms of location and safe removal. For this reason we wanted to review the existing literature on this subject.

RECENT FINDINGS

In high-activity robotic centers, robot-assisted partial nephrectomy (RAPN) is a safe and efficacious surgical approach for completely endophytic renal tumors. As research innovation, the application of the radio-guided occult lesion localization technique (ROLL) facilitates the location and complete excision of the tumor during surgery. There are few studies that specifically report the experience with completely endophytic renal tumors. The endophytic tumor is usually smaller than exophytic. Frequently it represents a high complexity value in the different Score systems reported in the last decade. This surgery should be performed by experienced urologists regardless of the surgical approach they prefer (open, laparoscopic, or robotic). It is necessary to develop new techniques for intraoperative easy localization and intraoperative evaluation of surgical margins.

Retroperitoneal Laparoscopic Partial Nephrectomy Versus Radical Nephrectomy for Clinical T1 Renal Hilar Tumor: Comparison of Perioperative Characteristics and Short-Term Functional and Oncologic Outcomes

PURPOSE

To present our single-center experience with retroperitoneal laparoscopic partial nephrectomy (LPN) and retroperitoneal laparoscopic radical nephrectomy (LRN) for T1 renal hilar tumors and evaluate which one is better.

METHODS

A retrospective review of 63 patients with hilar tumors undergoing retroperitoneal LPN or LRN was performed. The perioperative characteristics, change in estimated glomerular filtration rate (eGFR) from baseline to month 3, and oncologic outcomes were summarized.

RESULTS

In total, 25 patients underwent LPN, and 38 patients underwent LRN. The mean tumor size in the LPN and LRN groups was 4.5 and 4.9 cm, respectively. The mean operation time was longer in the LPN group than that in the LRN group (212.5 minutes versus 160.7 minutes, respectively; P < .05). Patients undergoing the LPN had a longer median length of hospital stay after surgery (9 days versus 7 days, P < .05). Four percent of patients in the LPN group experienced postoperative complications compared with 5% of patients in the LRN group, which was not significantly different. Compared with preoperative eGFR, postoperative eGFR at 3 months decreased by 15.2 mL/min/1.73 m² and 27.8 mL/min/1.73 m² in the LPN and the LRN groups, respectively (P < .05). There was one local recurrence in the LPN group and three local or distant recurrences in the LRN group (P > .05).

CONCLUSIONS

In experienced hands, although retroperitoneal LRN can result in shorter operation times and shorter lengths of stay, retroperitoneal LPN can preserve renal function better than LRN. Retroperitoneal LPN should be the priority in selected patients with T1 renal hilar tumors, especially for patients with renal insufficiency.

Robust augmented reality registration method for localization of solid organs' tumors using CT-derived virtual biomechanical model and fluorescent fiducials

BACKGROUND

Augmented reality (AR) is the fusion of computer-generated and real-time images. AR can be used in surgery as a navigation tool, by creating a patient-specific virtual model through 3D software manipulation of DICOM imaging (e.g., CT scan). The virtual model can be superimposed to real-time images enabling transparency visualization of internal anatomy and accurate localization of tumors. However, the 3D model is rigid and does not take into account inner structures' deformations. We present a concept of automated AR registration, while the organs undergo deformation during surgical manipulation, based on finite element modeling (FEM) coupled with optical imaging of fluorescent surface fiducials.

METHODS

Two 10 × 1 mm wires (pseudo-tumors) and six 10 × 0.9 mm fluorescent fiducials were placed in ex vivo porcine kidneys (n = 10). Biomechanical FEM-based models were generated from CT scan. Kidneys were deformed and the shape changes were identified by tracking the fiducials, using a near-infrared optical system. The changes were registered automatically with the virtual model, which was deformed accordingly. Accuracy of prediction of pseudo-tumors' location was evaluated with a CT scan in the deformed status (ground truth). In vivo: fluorescent fiducials were inserted under ultrasound guidance in the kidney of one pig, followed by a CT scan. The FEM-based virtual model was superimposed on laparoscopic images by automatic registration of the fiducials.

RESULTS

Biomechanical models were successfully generated and accurately superimposed on optical images. The mean measured distance between the estimated tumor by biomechanical propagation and the scanned tumor (ground truth) was 0.84 ± 0.42 mm. All fiducials were successfully placed in in vivo kidney and well visualized in near-infrared mode enabling accurate automatic registration of the virtual model on the laparoscopic images.

CONCLUSIONS

Our preliminary experiments showed the potential of a biomechanical model with fluorescent fiducials to propagate the deformation of solid organs' surface to their inner structures including tumors with good accuracy and automatized robust tracking.

Retroperitoneoscopic Partial Nephrectomy for Moderately Complex Ventral Hilar Tumors: Surgical Technique and Trifecta Outcomes from a Single Institution in China

OBJECTIVES

T1 ventral renal hilar tumors (VRHTs) represent a very special type of tumor, for which laparoscopic partial nephrectomy (LPN) by the retroperitoneal approach is challenging. In this study, we report our surgical technique and Trifecta results.

METHODS

Renal rotation technique has been established for retroperitoneal laparoscopic partial nephrectomy (RLPN) for VRHTs in our institution. Trifecta was used as a composite outcome measure for assessing quality of PLPN using this technique. A retrospective analysis of RLPN cases in 12 patients with VRHTs was performed.

RESULTS

Mean tumor size was 3.4 cm and median R.E.N.A.L. score was 8 (range 7-9). Mean warm ischemia time was 23.1 minutes, suture time 28.1 minutes, estimated blood loss 139.2 mL, operation time 122.8 minutes, and median hospital stay was 4 days. Three patients (25.0%) had Clavien-Dindo grade I-II complications. Seven patients (58.3%) achieved Trifecta. Postoperative pathological examination showed renal cell carcinoma in all cases with negative surgical margin. A median follow-up of 7 months revealed no local recurrence or distant metastases.

CONCLUSIONS

Our Trifecta outcomes demonstrate that RLPN with renal rotation technique is feasible, safe, and effective for moderately complex VRHTs. The short-term functional and oncologic outcomes are promising; however, long-term follow-up is needed.

Comparison of robot-assisted and laparoscopic partial nephrectomy for complex renal tumours with a RENAL nephrometry score ≥7: peri-operative and oncological outcomes

OBJECTIVE

To evaluate the peri-operative, functional and oncological outcomes of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) for moderately or highly complex tumours (defined as RENAL nephrometry score ≥7).

PATIENTS AND METHODS

We retrospectively analysed the medical charts of 216 patients with complex tumours who underwent LPN (n = 135) or RAPN (n = 81) between 2008 and 2014. Peri-operative data, pathological variables, complications, functional and oncological outcomes were reviewed.

RESULTS

Demographic characteristics were similar in the two groups. LPN was associated with a longer operating time (149.6 vs 135.6 min; P = 0.017) and greater estimated blood loss (220.8 vs 196.5 mL; P = 0.013). RAPN was associated with a higher direct cost. There were no differences in warm ischaemia time, transfusion rate, conversion rate, hospital stay, operative complications and estimated glomerular filtration rate change at 6 months after surgery. The mean follow-ups for LPN and RAPN were 31.4 and 16.5 months, respectively. The 3-year recurrence-free survival rate was 95.2% for LPN and 97.1% for RAPN (P = 0.71).

CONCLUSION

In patients with complex tumours, RAPN and LPN provided acceptable and similar results in terms of peri-operative, functional and oncological outcomes. RAPN was superior to LPN in terms of estimated blood loss and operating time, and LPN was the more cost-effective approach. Both surgery techniques remain viable options in the management of complex tumours with RENAL scores ≥7.

Outcomes and limitations of laparoscopic and robotic partial nephrectomy

PURPOSE OF REVIEW

The objective of this review article is to summarize and critically analyze the studies published in the previous year and report perioperative, functional, and oncologic outcomes after laparoscopic partial nephrectomy (LPN) and robot-assisted partial nephrectomy (RAPN).

RECENT FINDINGS

Recent case series studies evaluating LPN confirmed the good oncologic results of this approach at intermediate and long-term follow-ups. Recent studies investigating RAPN confirmed the promising perioperative outcomes reported in the initial case series. Many studies tested and demonstrated the feasibility of both procedures in the treatment of very complex cases represented by tumors larger than 4 cm, hilar/central tumors, endophytic tumors, or tumors located in solitary kidney. Comparative studies confirm advantages in favor of RAPN in comparison with LPN, mainly in terms of warm ischemia time and perioperative outcomes. A recent matched pair analysis showed equivalent perioperative and functional outcomes between RAPN and open partial nephrectomy (OPN).

SUMMARY

LPN and above all RAPN represent valid alternatives to OPN in the conservative treatment of renal tumors. Both procedures can be proposed also for the treatment of complex cases. Further, well conducted, comparative studies between RAPN and OPN are needed to test the ability of RAPN as an alternative to OPN in the treatment of more complex cases.