Role of minimally invasive partial nephrectomy in the management of renal mass

Robotic partial nephrectomy: Indications, patient selection, and setup for success

Robot-assisted partial nephrectomy (RAPN) has readily become the benchmark treatment of small renal masses (SRMs). The management of SRMs is focused on preserving renal function and limiting the morbidity of a traditional open operation, thus greatly impacting overall prognosis and long-term survival. Indications and techniques have evolved over the last 2 decades. In this article, we discuss the application of this nephron-sparing technique regarding its indications, surgical considerations, and functional outcomes.

The evolving management of small renal masses

Small renal masses (SRMs) are a heterogeneous group of tumours with varying metastatic potential. The increasing use and improving quality of abdominal imaging have led to increasingly early diagnosis of incidental SRMs that are asymptomatic and organ confined. Despite improvements in imaging and the growing use of renal mass biopsy, diagnosis of malignancy before treatment remains challenging. Management of SRMs has shifted away from radical nephrectomy, with active surveillance and nephron-sparing surgery taking over as the primary modalities of treatment. The optimal treatment strategy for SRMs continues to evolve as factors affecting short-term and long-term outcomes in this patient cohort are elucidated through studies from prospective data registries. Evidence from rapidly evolving research in biomarkers, imaging modalities, and machine learning shows promise in improving understanding of the biology and management of this patient cohort.

Robot-assisted versus conventional laparoscopic partial nephrectomy for renal hilar tumors: Parenchymal preservation and functional recovery

OBJECTIVE

To determine whether robot-assisted laparoscopic partial nephrectomy (RALPN) can benefit patients in terms of functional recovery in the treatment of renal hilar tumors compared to conventional laparoscopic partial nephrectomy (CLPN).

METHODS

Between January 2019 and July 2021, patients with hilar tumors who underwent partial nephrectomy (PN) were acquired at our center and were classified into RALPN and CLPN groups. Ipsilateral parenchymal volume (IPV) and glomerular filtration rate (GFR) were determined independently 3-5 days before and 3 months after PN using contrast-enhanced computed tomography and nuclear renal scans. Pearson correlation was used to determine the link between ipsilateral GFR preservation and IPV preserved. Concurrently, multivariable analysis was employed to determine characteristics associated with functional recovery.

RESULTS

A total of 96 patients with hilar tumors were studied, of which 41 received RALPN and 55 received CLPN. Excisional parenchymal volume was 27 and 37 cm³ (p = 0.005) in RALPN and CLPN groups, respectively, and IPV preserved was 77% and 68% (p < 0.001). Furthermore, the ipsilateral GFR preserved was 77.7% and 75.3%, respectively (p = 0.003). On Pearson correlation, ipsilateral GFR preservation was linked with IPV preserved (r = 0.36, p < 0.001). According to a multivariate study, baseline GFR, IPV preserved, and surgical procedures (RALPN vs. CLPN) were significant factors influencing functional recovery.

CONCLUSION

Our study suggests that RALPN, rather than CLPN, can achieve better functional recovery in the treatment of hilar tumors due to its ability to win more IPV preserved. RALPN should be recommended as the first-line treatment for hilar tumors, but randomized controlled trials are required to validate our findings.

Application and clinical efficacy of modified early unclamping technique in robot-assisted laparoscopic partial nephrectomy

OBJECTIVE

To investigate the clinical safety and efficacy of a modified early unclamping technique in robot-assisted laparoscopic partial nephrectomy (RAPN).

METHODS

The clinical data of 38 patients with renal tumors who underwent the modified early unclamping technique in RAPN surgery admitted to the Department of Urology, the Third People's Hospital of Hangzhou and the First Affiliated Hospital of Nanchang University from January 2018 to April 2021 were retrospectively analyzed. The control group consisted of 78 patients with renal tumors who underwent standard clamping during the RAPN surgery completed by the same surgeon during the same period. The perioperative-related indicators and postoperative renal function recovery were analyzed and compared between the two groups.

RESULTS

All patients (n = 116) finished the RAPN successfully, and none were transferred to radical or open surgery in either group. The warm ischemia time in the modified early unclamping group was significantly lower than that in the standard clamping group (P < 0.001). After surgery, the renal function index at each time point in the modified early unclamping group was higher than that in the standard clamping group; renal function gradually returned to near preoperative levels after 3 months in both groups. Postoperative follow-up showed no tumor recurrence or metastasis.

CONCLUSION

The application of a modified early unclamping technique in RAPN surgery is safe and feasible. Compared with standard clamping, modified early unclamping can significantly shorten the warm ischemia time of kidneys without increasing the volume of intraoperative blood loss and complications, which helps to protect the postoperative renal function of patients.

Comparison between minimally-invasive partial and radical nephrectomy for the treatment of clinical T2 renal masses: results of a 10-year study in a tertiary care center

BACKGROUND

Even if partial nephrectomy (PN) is nowadays considered the standard for managing cT1 renal masses, its role in the management of cT2 kidney tumors is controversial. We aimed to compare oncologic and functional outcomes of minimally invasive radical nephrectomy (RN) and PN in cT2 renal masses.

METHODS

Patients with cT2 renal masses underwent minimally-invasive PN or RN performed by a highly experienced single surgeon from 2009 to 2019 were considered. Demographic, perioperative and functional variables were compared. Cumulative incidence plot and competing risks regression (CRR) models were used to test differences in 5-year cancer-specific mortality (CSM) and 5-year other-cause mortality (OCM) rates. Kaplan-Meier and Cox regression model was used to test differences in 5-year progression free survival (PFS) rates.

RESULTS

Overall, 52 PN vs. 64 RN patients were identified. Relative to RN, PN patients recorded higher rates of complications (25% vs. 7.8%, P=0.02) but lower upstaging rate (≥pT3a 64.1% vs. 19.2%, P<0.0001). Functional outcomes were in favor of PN (all P<0.001). No differences were recorded between 5-year CSM and OCM according to nephrectomy type. At CRR models, older age and upstaging were independent predictors of 5-year OCM and CSM, respectively (all P<0.01). Finally, only upstaging, high grade tumors and presence of positive surgical margins were identified as independent predictors of 5-year PFS (all P<0.01).

CONCLUSIONS

In experienced hands the treatment of cT2 renal neoplasms with minimally-invasive PN is feasible, providing perioperative and oncological safety profiles comparable to RN, with advantages in terms of functional outcomes.