Tumour in solitary kidney: laparoscopic partial nephrectomy vs laparoscopic cryoablation

Is Ablation Suitable For Small Renal Masses (SRMs)? A Meta-Analysis

RATIONALE AND OBJECTIVES

To compare perioperative and oncology outcomes of ablation and partial nephrectomy in small renal masses (SRMs).

METHODS

We conduct this meta-analysis strictly according to the PRISMA standard, and the quality evaluation follows the AMSTAR standard. Four databases, Embase, PubMed, Cochrane Library, and Web of Science, were systematically searched. The search time range is from database creation to November 2023. Stata16 statistical software was used for statistical analysis. Weighted mean difference (WMD) represented continuity variables, odds ratio or relative risk (OR/RR) represented dichotomies variables, and 95% confidence intervals (95%CI) were calculated.

RESULTS

A total of 27 studies, including 6030 patients. Results showed that patients undergoing partial nephrectomy were younger (WMD = -5.45 years, 95%CI [-7.44, -3.46], P < 0.05), had longer operation time (WMD = 64.91 min, 95%CI [44.47, 85.34], P < 0.05), had longer length of stay (WMD = 2.91 days, 95%CI [2.04, 3.78], P < 0.05), and had more estimated blood loss (WMD = 97.76 ml, 95%CI [69.48, 126.04]. P < 0.05), the overall complication rate was higher (OR = 1.84, 95%CI [1.48, 2.29], P < 0.05), the major complication rate was higher (OR = 1.98, 95%CI [1.36, 2.88], P < 0.05), and the recurrence rate was lower (OR = 0.32, 95%Cl [0.20, 0.50], P < 0.05). However, there were no differences between ablation and partial nephrectomy in cancer-specific survival (CSS) (HR = 2.07, 95%CI [0.61, 7.04], P > 0.05), overall survival (OS) (HR = 1.24, 95%CI [0.58, 2.65], P > 0.05), and recurrence-free survival (RFS) (HR = 2.68, 95%CI [0.91, 7.88], P > 0.05).

CONCLUSION

Patients undergoing partial nephrectomy are younger, have longer operation time and length of stay, and have higher complication rate. However, there was no significant difference in CSS, OS, and RFS between partial nephrectomy and ablation, but more well-designed, high-quality studies are needed to confirm this.

Long-term Renal Function Outcomes After Stereotactic Ablative Body Radiotherapy for Primary Renal Cell Carcinoma Including Patients with a Solitary Kidney: A Report from the International Radiosurgery Oncology Consortium of the Kidney

BACKGROUND AND OBJECTIVE

Renal function preservation is particularly important following nonoperative treatment of localized renal cell carcinoma (RCC) since patients are often older with medical comorbidities. Our objective was to report long-term renal function outcomes after stereotactic ablative radiotherapy (SABR) including patients with a solitary kidney.

METHODS

Patients with primary RCC treated with SABR with ≥2 yr of follow-up at 12 International Radiosurgery Consortium for Kidney institutions were included. Renal function was measured by estimated glomerular filtration rate (eGFR).

KEY FINDINGS AND LIMITATIONS

In total, 190 patients (56 with a solitary kidney) underwent SABR and were followed for a median of 5.0 yr (interquartile range [IQR]: 3.4-6.8). In patients with a solitary kidney versus bilateral kidneys, pre-SABR eGFR (mean [standard deviation]) was 61.1 (23.2) versus 58.0 (22.3) ml/min (p = 0.32) and the median tumor size was 3.65 cm (IQR: 2.59-4.50 cm) versus 4.00 cm (IQR: 3.00-5.00 cm; p = 0.026). At 5 yr after SABR, eGFR decreased by -14.5 (7.6) and -13.3 (15.9) ml/min (p = 0.67), respectively, and there were similar rates of post-SABR dialysis (3.6% [n = 2/56] vs 3.7% [n = 5/134]). A multivariable analysis demonstrated that increasing tumor size (odds ratio [OR] per 1 cm: 1.57; 95% confidence interval [CI]: 1.14-2.16, p = 0.0055) and baseline eGFR (OR per 10 ml/min: 1.30; 95% CI: 1.02-1.66, p = 0.034) were associated with an eGFR decline of ≥15 ml/min at 1 yr.

CONCLUSIONS AND CLINICAL IMPLICATIONS

With long-term follow-up after SABR, kidney function decline remains moderate, with no observed difference between patients with a solitary kidney and bilateral kidneys. Tumor size and baseline eGFR are dominant factors predictive of long-term renal function decline.

PATIENT SUMMARY

With long-term follow-up, stereotactic ablative radiotherapy (SABR) yields moderate long-term renal function decline and low dialysis rates even in patients with a solitary kidney. SABR thus represents a promising noninvasive, nephron-sparing option for patients with localized renal cell carcinoma.

Stage IA papillary and chromophobe renal cell carcinoma: effectiveness of cryoablation and partial nephrectomy

OBJECTIVES

To evaluate the effectiveness of cryoablation compared to partial nephrectomy in patients with stage IA papillary and chromophobe renal cell carcinoma (pRCC; chRCC).

MATERIAL AND METHODS

The 2004-2016 National Cancer Database was queried for adult patients with stage IA pRCC or chRCC treated with cryoablation or partial nephrectomy. Patients receiving systemic therapy or radiotherapy, as well as those with bilateral RCC or prior malignant disease were excluded. Overall survival (OS) was assessed using Kaplan-Meier plots and Cox proportional hazard regression models. Nearest neighbor propensity matching (1:1 cryoablation:partial nephrectomy, stratified for pRCC and chRCC) was used to account for potential confounders.

RESULTS

A total of 11122 stage IA renal cell carcinoma patients were included (pRCC 8030; chRCC 3092). Cryoablation was performed in 607 (5.5%) patients, and partial nephrectomy in 10515 (94.5%) patients. A higher likelihood of cryoablation treatment was observed in older patients with non-private healthcare insurance, as well as in those with smaller diameter low-grade pRCC treated at non-academic centers in specific US geographic regions. After propensity score matching to account for confounders, there was no statistically significant difference in OS comparing cryoablation vs partial nephrectomy in patients with pRCC (HR = 1.3, 95% CI: 0.96-1.75, p = 0.09) and those with chRCC (HR = 1.38, 95% CI: 0.67-2.82, p = 0.38).

CONCLUSION

After accounting for confounders, cryoablation, and partial nephrectomy demonstrated comparable OS in patients with stage IA papillary and chromophobe RCC. Cryoablation is a reasonable treatment alternative to partial nephrectomy for these histological RCC subtypes when radiologically suspected or diagnosed after biopsy.

CRITICAL RELEVANCE STATEMENT

Cryoablation might be considered as an upfront treatment alternative to partial nephrectomy in patients with papillary and chromophobe stage IA renal cell carcinoma, as both treatment approaches yield comparable oncological outcomes.

KEY POINTS

The utilization of cryoablation for stage IA papillary and chromophobe RCC increases. In the National Cancer Database, we found specific patterns of use of cryoablation. Cryoablation and partial nephrectomy demonstrate comparable outcomes after accounting for confounders.

Perioperative, functional, and oncological outcomes after cryoablation or partial nephrectomy for small renal masses in solitary kidneys: a systematic review and meta-analysis

AIM

This study aims to compare the perioperative, functional, and oncological outcomes of cryoablation (CA) and partial nephrectomy (PN) for managing small renal masses in patients with solitary kidneys. The study seeks to assess the efficacy and safety of both interventions, evaluating their impact on kidney function and their ability to mitigate cancer recurrence.

METHODS

Searches were systematically conducted on PubMed, Scopus, EMBASE, SinoMed, and Google Scholar, identifying seven observational studies. Statistical analysis was performed using Stata v.12.0 and Review Manager version 5.2. Results for dichotomous variables are expressed using odds ratios, and weighted mean differences are used for continuous variables.

RESULTS

Our findings revealed that patients undergoing CA experienced significantly shorter operative time (p < 0.0001), reduced estimated blood loss (p < 0.00001), a shorter length of stay (p = 0.0001), and fewer postoperative complications (p = 0.02) compared to those undergoing PN. Although the CA group exhibited a lower transfusion rate (p = 0.69) compared with the PN group, the difference was not statistically significant. The combined data analysis demonstrated a significantly lower increase in serum creatinine levels after surgery in the CA group compared with the PN group (p = 0.003). Similarly, there was a noteworthy decrease in the estimated glomerular filtration rate after surgery in the PN group compared with the CA group (p < 0.0001). While not statistically significant, the CA group showed a lower postoperative dialysis rate (p = 0.11). Regarding oncological outcomes, the analysis revealed no significant differences between CA and PN concerning local recurrence (p = 0.2) and distant metastasis (p = 0.12), respectively.

CONCLUSIONS

Our analysis indicates comparable efficacy between PN and CA in controlling tumour recurrence and metastasis. However, CA is associated with superior preservation of renal function, significantly enhanced perioperative outcomes, and fewer postoperative complications. Based on our data, it can be inferred that the scope for applying CA might be expanded to encompass more patients seeking a less invasive treatment option.

Perioperative, functional, and oncologic outcomes after ablation or partial nephrectomy for solitary renal tumors: a systematic review and meta-analysis of comparative trials

Objectives

The perioperative, functional, and oncological outcomes of patients with solitary small renal tumors (SRMs) treated with ablation (AT) or partial nephrectomy (PN) remain controversial. The aim of this study was to compare the outcomes of these two surgical techniques.

Methods

In April 2023, we conducted a literature search in several widely used databases worldwide, including PubMed, Embase, and Google Scholar. Review Manager was used to compare various parameters. The study was registered with PROSPERO (CRD42022377157).

Results

Our final meta-analysis included 13 cohort studies with a total of 2,107 patients. Compared to partial nephrectomy (PN), ablation (AT) had shorter hospital stays (WMD -2.37 days, 95% CI -3.05 to -1.69; p < 0.00001), shorter operating times (WMD -57.06 min, 95% CI -88.92 to -25.19; p = 0.0004), less postoperative creatinine increases (WMD -0.17 mg/dL, 95% CI -0.29 to -0.05; p = 0.006), less postoperative glomerular filtration rate decreases (WMD -9.84 mL/min/1.73 m2, 95% CI -14.25 to -5.44; p < 0.0001), less postoperative new-onset chronic kidney disease (OR 0.33, 95% CI 0.16 to 0.71; p = 0.005), and less intraoperative blood loss (WMD -285.92 ml, 95% CI -428.44 to -143.40; p < 0.0001). The transfusion rate was lower in the ablation group (OR 0.17, 95% CI 0.06 to 0.51; p = 0.001). The risk of local recurrence was higher in the ablation group (OR 2.96, 95% CI 1.27 to 6.89; p = 0.01), while the risk of distant metastasis was higher in the partial nephrectomy group (OR 2.81, 95% CI 1.28 to 6.18; p = 0.01). The intraoperative and postoperative complication rates were lower in the ablation group (OR 0.23, 95% CI 0.08 to 0.62; p = 0.004 and OR 0.21, 95% CI 0.11 to 0.38; p < 0.00001, respectively). However, overall survival, postoperative dialysis rate, and tumor-specific survival were not different between the two groups.

Conclusions

Our data suggest that ablation and partial nephrectomy are equally safe and effective in the treatment of small solitary kidney tumors and are better options for patients with poor preoperative physical condition or poor renal function.

Percutaneous cryoablation versus partial nephrectomy for cT1b renal tumors: An inverse probability weight analysis

PURPOSE

To investigate differential clinical outcomes in patients treated with partial nephrectomy (PN) vs. percutaneous cryoablation (PCA) for cT1b renal tumors.

MATERIALS AND METHODS

We retrospectively analyzed the records of 119 patients who had undergone PN (n = 90) or PCA (n = 29) for cT1b renal tumors. Inverse probability weighting (IPW) was used for balancing patient demographics, including renal function and tumor complexity. Perioperative complications, renal function preservation rates, and oncological outcomes such as local recurrence-free, metastasis-free, cancer-specific, and overall survival were compared using IPW-adjusted restricted mean survival times (RMSTs).

RESULTS

PCA was more likely to be selected for octogenarians (odds ratio: 11.4, 95% confidence interval [CI]: 3.33-45.1). During the median follow-up of 43 months in the PCA group and 36.5 months in the PN group, unablated local residue or local recurrence was noted in 6 patients in the PCA group and local recurrence was noted in 4 patients in the PN groups. Of the 6 patients in the PCA group, 4 underwent salvage PCA, and local control had been achieved at the last visit. In the IPW-adjusted population, PCA had significantly worse local recurrence-free survival compared with PN (IPW-adjusted RMST difference: -22.7 months, 95% CI: -45.3 to -0.4, P = 0.046). IPW-adjusted RMST for metastasis-free survival (P = 0.23), cancer-specific survival (P = 0.77), and overall survival (P = 0.11) did not differ between PCA and PN. In addition, PN was not a predictor for local control failure at the last visit (odds ratio: 0.30, 95%CI: 0.05-1.29). There were no statistically significant differences between PN and PCA in renal function preservation or overall/severe complication rates.

CONCLUSIONS

In patients with cT1b renal tumor, although the local recurrence rate is higher for PCA than for PN, PCA provides comparable distant oncologic outcomes. PCA can be an alternative treatment option for elderly, comorbid patients, even those with cT1b renal tumors.

Comprehensive Management of Renal Masses in Solitary Kidneys

BACKGROUND

A renal mass in a solitary kidney (RMSK) has traditionally been managed with partial nephrectomy (PN), although radical nephrectomy (RN) is occasionally required. Most RMSK studies have focused on patients for whom PN was achieved.

OBJECTIVE

To provide a comprehensive analysis of the management strategies/outcomes for an RMSK and address knowledge deficits regarding this challenging disorder.

DESIGN, SETTING, AND PARTICIPANTS

A total of 1024 patients diagnosed with an RMSK (1975-2022) were retrospectively evaluated. Baseline characteristics and pathologic/functional/survival outcomes were analyzed.

INTERVENTION

PN/RN/cryoablation (CA)/active surveillance (AS).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Functional outcomes, perioperative morbidity/mortality, and 5-yr recurrence-free survival (RFS) were evaluated. Kruskal-Wallis and chi-square tests were used to compare cohorts, and log-rank test and Cox proportional hazard model were used for survival analysis.

RESULTS AND LIMITATIONS

Of 1024 patients, 842 underwent PN (82%), 102 CA (10%), 54 RN (5%), and 26 AS (3%). The median tumor size and RENAL([R]adius [tumor size as maximal diameter], [E]xophytic/endophytic properties of tumor, [N]earness of tumor deepest portion to collecting system or sinus, [A]nterior [a]/posterior [p] descriptor, and [L]ocation relative to polar lines) score were 3.7 cm and 8, respectively. The median follow-up was 53 mo. For PN, 95% were clamped, and the median warm and cold ischemia times were 22 and 45 min, respectively. For PN, the median preoperative glomerular filtration rate (GFR) was 57 ml/min/1.73 m², and the median new baseline and 5-yr GFRs were 47 and 48 ml/min/1.73 m², respectively. Dialysis-free survival for PN was 97% at 5 yr. Twenty-two (2.1%) patients with clear-cell renal cell carcinoma and RENAL score ≥10 (median = 11) received tyrosine kinase inhibitors (TKIs) to facilitate PN, leading to 57% median decrease of tumor volume; PN was accomplished in 20 (91%). Forty-one patients had planned RN (4.0%), most often due to severe pre-existing chronic kidney disease (CKD), and 13 were converted from PN to RN (1.5%). Clavien III-V perioperative complications were observed in 80 (8%) patients and 90-d mortality was 0.6%. Five-year RFS for PN, CA, and RN were 83%, 80%, and 72%, respectively (p = 0.03 for PN vs RN).

CONCLUSIONS

Nephron-sparing approaches are feasible and successful in most RMSK patients. PN for an RMSK is often challenging but can be facilitated by selective use of TKIs. RN is occasionally required due to severe CKD, over-riding oncologic concerns, or conversion from PN. This is the first large RMSK study to provide a comprehensive analysis of all management strategies/outcomes.

PATIENT SUMMARY

Kidney cancer in a solitary kidney is a major challenge for achieving cancer-free status and avoiding dialysis. Although partial nephrectomy is the principal treatment for a renal mass in a solitary kidney, other options are occasionally required to optimize outcomes.

Differential efficacy of ablation therapy versus partial nephrectomy between clinical T1a and T1b renal tumors: A systematic review and meta-analysis

PURPOSE

To assess the differential clinical outcomes of patients treated with partial nephrectomy (PN) vs. those treated with ablation therapy (AT) such as radiofrequency ablation, cryoablation and microwave ablation for cT1b compared to cT1a renal tumors.

MATERIALS AND METHODS

Multiple databases were searched for articles published before August 2021. Studies were deemed eligible if they compared clinical outcomes in patients who underwent PN with those who underwent AT for cT1a and/or cT1b renal tumors.

RESULTS

Overall, 27 studies comprising 13,996 patients were eligible for this meta-analysis. In both cT1a and cT1b renal tumors, there was no significant difference in the percent decline of estimated glomerular filtration rates or in the overall/severe complication rates between PN and AT. Compared to AT, PN was associated with a lower risk of local recurrence in both patients with cT1a and cT1b tumors (cT1a: pooled risk ratio [RR]; 0.43, 95% confidence intervals [CI]; 0.28-0.66, cT1b: pooled RR; 0.41, 95%CI; 0.23-0.75). Subgroup analyses regarding the technical approach revealed no statistical difference in local recurrence rates between percutaneous AT and PN in patients with cT1a tumors (pooled RR; 0.61, 95%CI; 0.32-1.15). In cT1b, however, PN was associated with a lower risk of local recurrence (pooled RR; 0.45, 95%CI; 0.23-0.88). There was no difference in distant metastasis or cancer mortality rates between PN and AT in patients with cT1a, or cT1b tumors.

CONCLUSIONS

AT has a substantially relevant disadvantage with regards to local recurrence compared to PN, particularly in cT1b renal tumors. Despite the limitations inherent to the nature of retrospective and unmatched primary cohorts, percutaneous AT could be used as a reasonable alternative treatment for well-selected patients with cT1a renal tumors.

A Systematic Review and Meta-Analysis of Minimally Invasive Partial Nephrectomy Versus Focal Therapy for Small Renal Masses

Background

Minimally invasive partial nephrectomy (MIPN) and focal therapy (FT) are popular trends for small renal masses (SRMs). However, there is currently no systematic comparison between MIPN and FT of SRMs. Therefore, we systematically study the perioperative, renal functional, and oncologic outcomes of MIPN and FT in SRMs.

Methods

We have searched the Embase, Cochrane Library, and PubMed for articles between MIPN (robot-assisted partial nephrectomy and laparoscopic partial nephrectomy) and FT {radiofrequency ablation (RFA), microwave ablation (MWA), cryoablation (CA), irreversible electroporation, non-thermal [irreversible electroporation (IRE)] ablation, and stereotactic body radiation therapy (SBRT)}. We calculated pooled mean difference (MD), odds ratios (ORs), and 95% confidence intervals (CIs) (CRD42021260787).

Results

A total of 26 articles (n = 4,420) were included in the study. Compared with MIPN, the operating time (OP) of FT had significantly lower (SMD, −1.20; CI, −1.77 to −0.63; I2 = 97.6%, P &lt; 0.0001), estimated blood loss (EBL) of FT had significantly less (SMD, −1.20; CI, −1.77 to −0.63; I2 = 97.6%, P &lt; 0.0001), length of stay (LOS) had shorter (SMD, −0.90; CI, −1.26 to −0.53; I2 = 92.2%, P &lt; 0.0001), and estimated glomerular filtration rate (eGFR) of FT was significantly lower decrease (SMD, −0.90; CI, −1.26 to −0.53; I2 = 92.2%, P &lt; 0.0001). However, FT possessed lower risk in minor complications (Clavien 1–2) (OR, 0.69; CI, 0.45 to 1.07; I2 = 47%, P = 0.023) and overall complications (OR, 0.71; CI, 0.51 to 0.99; I2 = 49.2%, P = 0.008). Finally, there are no obvious difference between FT and MIPN in local recurrence, distant metastasis, and major complications (P &gt; 0.05).

Conclusion

FT has more advantages in protecting kidney function, reducing bleeding, shortening operating time, and shortening the length of stay. There is no difference in local recurrence, distant metastasis, and major complications. For the minimally invasive era, we need to weigh the advantages and disadvantages of all aspects to make comprehensive choices.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier PROSPERO (CRD42021260787).

Image-guided percutaneous cryoablation of T1b renal cell carcinomas in patients with comorbidities

PURPOSE

To investigate the influence of comorbidities and tumor characteristics on outcomes following percutaneous cryoablation (PCA) of T1b renal cell carcinoma (RCC).

MATERIALS AND METHODS

Age-adjusted Charlson comorbidity index (ACCI); standardized system for quantitating renal tumor size, location, and depth (RENAL nephrometry score [RNS]); and local tumor control and survival were retrospectively investigated in 28 patients who underwent PCA for stage T1b RCC. Risk factors for elevated serum creatinine levels were also investigated.

RESULTS

Complete ablation was obtained in 27 of 28 patients. Two cases of metastasis were observed; one patient died 12 months after PCA. Overall survival at 5 years was 79.1%, with a mean follow-up of 42.0 ± 16.0 months. Local tumor control was not correlated with the ACCI and RNS. Worsening renal function 3 months after PCA was observed in ten patients, and it correlated with the presence of single kidneys (7/28 patients; p = 0.023). Significant worsening of renal function continued until 1 year after PCA (p = 0.013). Having a single kidney was a risk factor for worsened renal function after PCA (odds ratio, 8.00; 95% confidence interval 1.170-54.724).

CONCLUSION

PCA for T1b RCC confers positive local tumor control regardless of comorbidities and tumor characteristics.

Stereotactic Body Radiotherapy for Palliation of Hematuria Arising From Urothelial Carcinoma of the Kidney in Unfavorable Surgical Candidates

INTRODUCTION

Hematuria can be a distressing and debilitating complication of urothelial carcinoma (UC) of the kidney for patients who are not candidates for surgery or ureteroscopic ablation. We retrospectively assessed the efficacy, tolerability, and safety of stereotactic body radiotherapy (SBRT) for controlling gross hematuria in this patient population.

MATERIALS AND METHODS

Institutional Review Board (IRB)-approved review of the records, laboratory values, pathology, and imaging of 8 consecutive patients treated with SBRT over a 5-year period for uncontrolled gross hematuria caused by UC of the renal pelvis or calyces.

RESULTS

Therapy was delivered in 3 to 5 treatments over 1 to weeks. Individual treatments lasted an average of 17.2 minutes. No patient experienced treatment-related pain, vomiting, or diarrhea. All enjoyed cessation of bleeding within a week of completing therapy. Hematuria recurred in 2 patients in 4 and 22 months. Of the patients who have not re-bled, 3 expired of metastatic disease or co-morbidities, and 3 remain alive up to 6 years posttreatment. Of patients who have survived longer than a year, creatinine has changed by -0.05 to +0.35, and estimated glomerular filtration rate has fallen by an average of 22%. No patient has required dialysis.

CONCLUSIONS

SBRT appears to be an effective and well-tolerated means of palliating gross hematuria secondary to UC of the renal pelvis or calyces in patients who are unfavorable candidates for nephrectomy or ureteroscopic ablation. Treatment was associated with a moderate decline in renal function.

Comparison of Robot-Assisted Laparoscopic Partial Nephrectomy with Laparoscopic Cryoablation in the Treatment of Localised Renal Tumours: A Propensity Score-Matched Comparison of Long-Term Outcomes

Preserving renal function and controlling oncological outcomes are pertinent when managing renal neoplasms. Cryoablation is the recommended treatment only for clinical T1a stage renal tumour. Here, we compared the outcomes of robot-assisted laparoscopic partial nephrectomy (RaPN) and laparoscopic cryoablation (LCA) in the treatment of patients with localised T1-T2 renal tumours. Overall, 86 patients who received RaPN and 78 patients underwent LCA were included in this study. The intraoperative, postoperative, and oncological outcomes in the LCA group were non-inferior to the RaPN group. Moreover, LCA demonstrated shorter operative time (267.45 ± 104.53 min vs. 138.56 ± 45.28 min, p < 0.001), lower blood loss (300.56 ± 360.73 mL vs. 30.73 ± 50.31 mL, p < 0.001), and slight renal function deterioration because of the reduced invasiveness, without compromising on the oncological outcomes.

Percutaneous CT-Guided Renal Cryoablation: Technical Aspects, Safety, and Long-Term Oncological Outcomes in a Single Center

Background and objectives: Cryoablation is emerging as a safe and effective therapeutic option for treating renal cell carcinoma. This study analyzed the safety and long-term oncological outcomes of cryoablation in our center. Materials and methods: Patients who underwent computed tomography (CT)-guided percutaneous cryoablation between February 2011 and June 2020 for one or more clinically localized renal tumors were identified. Technical success and treatment efficacy were assessed. Post-procedural complications were classified according to the Clavien-Dindo system. Recurrence-free survival was determined for biopsy-proven malignant renal tumors. Results: A total of 174 renal tumors, 78 of which were biopsy-proven malignant carcinomas, were treated in 138 patients (97 males and 41 females, mean age: 73 years, range: 43-89 years). Mean tumor size was 2.25 cm and 54.6% of the lesions required a complex approach. Technical success was achieved in 171 out of 174 tumors (98.3%). Primary treatment efficacy was 95.3% and increased to 98.2% when retreats were taken into account. The overall complication rate was 29.8%. No complications of Clavien-Dindo grade III or more were encountered. Median follow-up was 21.92 months (range: 0.02-99.87). Recurrence-free survival was 100% at 1 year, 95.3% (95% CI: 82.1%-98.8%) at 3 years, and 88.6% (95% CI: 71.8%-95.7%) at 5 years. Conclusions: Cryoablation is a safe and effective technique for the treatment of small renal lesions, with no major complications when performed by expert interventional radiologists. The multidisciplinary discussion is essential, especially considering the high number of histologically undetermined lesions. Our long-term oncological outcomes are encouraging and in line with the literature.

Functional and oncological outcome of percutaneous cryoablation versus laparoscopic partial nephrectomy for clinical T1 renal tumors: A propensity score-matched analysis

PURPOSE

To evaluate the clinical trifecta of percutaneous cryoablation (PCA) vs. laparoscopic partial nephrectomy (LPN) for cT1 renal tumors.

PATIENTS AND METHODS

We retrospectively analyzed the records of patients who had undergone 2 types of nephron sparing surgeries (NSS) PCA or LPN for cT1 renal tumors between November 2011 and December 2019. The cohorts were matched by one-to-one propensity scores based on patient demographics, renal function, and tumor complexity. Perioperative and oncological outcomes and preservation of renal function following surgery were compared.

RESULTS

After matching, a total of 180 patients who had undergone NSS for de novo renal tumors were evaluable: 90 for PCA and 90 for LPN. No statistically significant differences were noted among the measured baseline characteristics in the propensity score-matched cohorts. Overall perioperative complication rates were 5.5% in the PCA and 11.1% in the LPN groups (P = 0.28). The rate of eGFR preservation 1 to 3 months after surgery was significantly higher for PCA than for LPN (92.8 ± 11.5% vs. 88.5 ± 14.6%, P = 0.03). Median follow-up was 33 months for PCA and 18 months for LPN (P < 0.001). Three residual and 4 recurrent tumors were later diagnosed in the PCA group and 1 recurrent tumor in the LPN group. The 5-year local recurrence-free survival was lower for PCA than LPN (90.2% vs. 98.5%, P = 0.36). The 5-year metastasis-free survival rate was similar in both groups (98.4% vs. 100%, P = 0.38). The 5-year overall and cancer-specific survival rates were comparable in both groups (91.7% vs. 98.9%, P = 0.53, and 95% vs. 100%, P = 0.55, respectively).

CONCLUSIONS

Clinical T1 RCC patients are better treated with LPN if technically possible. Though PCA had a higher local recurrence rate, medium-term local control was not inferior to LPN. Additionally, PCA patients tended to retain renal function without severe complications. PCA appears to be a reasonable option for patients with high comorbidity at presentation.

Limitations of Available Studies Prevent Reliable Comparison Between Tumour Ablation and Partial Nephrectomy for Patients with Localised Renal Masses: A Systematic Review from the European Association of Urology Renal Cell Cancer Guideline Panel

The European Association of Urology (EAU) Renal Cell Carcinoma (RCC) Guideline Panel performed a protocol-driven systematic review (SR) on thermal ablation (TA) compared with partial nephrectomy (PN) for T1N0M0 renal masses, in order to provide evidence to support its recommendations. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed, and only comparative studies published between 2000 and 2019 were included. Twenty-six nonrandomised comparative studies were included, recruiting a total of 167 80 patients. Risk of bias (RoB) assessment revealed high or uncertain RoB across all studies, with the vast majority being retrospective, observational studies with poorly matched controls and short follow-up. Limited data showed TA to be safe, but its long-term oncological effectiveness compared with PN remains uncertain. A quality assessment of pre-existing SRs (n=11) on the topic, using AMSTAR, revealed that all SRs had low confidence rating, with all but two SRs being rated critically low. In conclusion, the current data are inadequate to make any strong and clear conclusions regarding the clinical effectiveness of TA for treating T1N0M0 renal masses compared with PN. Therefore, TA may be cautiously considered an alternative to PN for T1N0M0 renal masses, but patients must be counselled carefully regarding the prevailing uncertainties. We recommend specific steps to improve the evidence base based on robust primary and secondary studies. PATIENT SUMMARY: In this report, we looked at the literature to determine the effectiveness of thermoablation (TA) in the treatment of small kidney tumours compared with surgical removal. We found that TA could cautiously be offered as an option due to many remaining uncertainties regarding its effectiveness.

Active surveillance and focal ablation for small renal masses: a better solution for comorbid patients

The natural history of small renal masses (SRM) is still not well understood and they are frequently incidentally diagnosed in elderly patients. Therefore, there is a need for less invasive options sparing the patient from the side-effects related to conventional surgical treatment. PubMed and Medline database search was performed to look for new findings on active surveillance and focal therapy for SRM. Sixty-one articles published between 2002 and 2018 were selected for the purpose of the review. There is growing evidence confirming the safety of active surveillance in patients at surgical risk and there appears to be a satisfactory intermediate-term outcome of focal treatment of SRM. In the group of elderly patients with a decreased life expectancy active surveillance appears to be the most appropriate approach. The future of minimally invasive therapy appears bright, especially with the improvement of new imaging modalities.

Systematic Review of Contemporary Evidence for the Management of T1 Renal Cell Carcinoma: What IRs Need to Know for Kidney Cancer Tumor Boards

Renal cell carcinoma is a relatively common malignancy, with 60 to 70 thousand cases a year in the United States alone. Increased utilization of cross-sectional imaging has led to an increase in the number of early renal cell cancers seen by the medical establishment. In addition, certain patient populations have an increased risk of developing kidney cancers which may mandate aggressive screening protocols. This article discusses the epidemiology of renal cell cancers; discusses the current management guidelines from multiple specialty societies; discusses some of the surgical and interventional techniques used in the treatment of such lesions; and provides a review of the literature regarding treatments of early-stage renal cell cancers.

Comparison among cryoablation, radiofrequency ablation, and partial nephrectomy for renal cell carcinomas sized smaller than 2 cm or sized 2-4 cm: A population-based study

This study aimed to compare radiofrequency ablation (RFA), cryoablation (CRA), and partial nephrectomy (PN) for renal cell carcinoma (RCC) sized ≤2 cm or 2 to 4 cm.The Surveillance, Epidemiology, and End Results (SEER) database was used to identify 17,234 patients diagnosed with T1aN0M0 RCC from 2004 to 2015. Overall survival (OS) and cancer-specific survival (CSS) were compared among patients who were treated using PN, CRA, or RFA. The Cox proportional hazards model was used to determine prognostic factors for survival.In patients with RCCs sized 2 to 4 cm, better OS and CSS were observed with PN than with CRA or RFA. On multivariable analysis, compared to PN, CRA and RFA were independently associated with poor OS and CSS in patients with RCCs sized 2 to 4 cm. In patients with RCCs sized ≤2 cm, better OS was observed with PN than with CRA or RFA; however, CSS was similar. On multivariable analysis, compared to PN, RFA was independently associated with poor OS in patients with RCCs sized ≤2 cm.CRA or RFA should not be recommended for patients with RCCs sized 2 to 4 cm; PN is an effective treatment modality in these patients. For patients with RCCs sized ≤2 cm, CRA can be an equally effective alternative to PN.

A comparison of outcomes for standard and multiplex partial nephrectomy in a solitary kidney: The National Cancer Institute experience

OBJECTIVES

To study the short and intermediate surgical, renal functional, and oncologic outcomes of multiplex partial nephrectomy (mPN) and standard partial nephrectomy (sPN) in the setting of a solitary kidney.

PATIENTS AND METHODS

Review of a prospectively maintained database of patients undergoing solitary kidney partial nephrectomy at our institution was performed. Patients were stratified into 2 cohorts: mPN-where 3 or more renal tumors were resected and sPN-where 1 or 2 tumors were resected. Perioperative, renal functional, and oncological outcomes were compared.

RESULTS

Ninety-three patients with a solitary kidney underwent a total of 121 surgical procedures; 43 (35.5%) were sPN and 78 (64.4%) were mPN. The total and major (Clavien Grade III and IV) complication rates between sPN and mPN were similar (57.1% vs. 70.1%, P = 0.2; 31.0% vs. 35.1%, P = 0.3). At 12 months post-op, the percentage of patients with eGFR > 45 was similar in each group (sPN 87.0%, mPN 73.7%; P = 0.2), and long-term hemodialysis rates were 4.7% and 6.4%, respectively. Completion nephrectomy was performed in 2.3% of sPN and 2.6% of mPN. At a median follow-up of 40.1 months, the metastasis rate was 8.6% in the sPN group and 4.1% in the mPN group (P = 0.4).

CONCLUSIONS

Partial nephrectomy in the setting of a solitary kidney can effectively preserve renal function. The renal functional and oncologic outcomes were similar in sPN and mPN, with low hemodialysis rates and complication rates within the expected range of these operations. Three or more tumors in a solitary kidney should not be a contraindication for nephron sparing surgery.

Partial nephrectomy vs cryoablation for T1a renal cell carcinoma: A comparison of survival benefit stratified by tumour size

OBJECTIVE

We compared the impact on survival outcomes of partial nephrectomy (PN) and cryoablation (CA) for patients diagnosed with T1a renal cell carcinoma (RCC).

PATIENTS AND METHODS

Among patients diagnosed between 2004 and 2014 in the Surveillance, Epidemiology and End Results program, we identified histologically confirmed T1aN0M0 RCC treated with PN (n = 17644) or CA (n = 868). Propensity score matching (PSM) was performed. Kaplan-Meier method, Cox proportional hazards model were used to calculate cancer specific mortality (CSM) and overall mortality (OM) in the unmatched and matched cohort, and in subgroups based on tumour size (< 2 cm, 2-3 cm, 3-4 cm). Sensitivity analyses were performed.

RESULTS

A total of 18512 patients were identified: PN (93.88%) and CA (6.12%). In the propensity-score matched cohort, for tumours ≤ 2 cm, the CA and PN groups had similar CSM (HR: 1.41, 95% CI: 0.32-6.31, p = 0.65) and OM (HR 0.97, 95%CI: 0.47-2.01, p = 0.93). For tumours 2-3 cm, CA was associated with similar CSM (HR 1.64, 95%CI: 0.67-4.03, p = 0.28) but higher OM (HR 2.05, 95%CI: 1.35-3.11, p < 0.001), compared with PN. For tumours 3-4 cm, CA was associated with increased CSM (HR: 3.76, 95% CI: 1.62-8.69, p = 0.002) and OM (HR 2.17, 95%CI: 1.48-3.18, p < 0.001).

CONCLUSION

For RCC ≤ 2 cm, PN and CA are equal in survival outcomes. For RCC 2-4 cm, PN may have a possible advantage over CA.

Cryoablation versus Partial Nephrectomy for Clinical Stage T1 Renal Masses: A Systematic Review and Meta-Analysis

Introduction: Cryoablation has been considered as the most efficacious ablative alternative to partial nephrectomy (PN) for selected patients. Our objective is to assess the existing evidence relating to the safety and efficacy of cryoablation compared with PN for clinical T1 renal masses.

Materials and Methods: A comprehensive search of PMC, EMBASE, and the Cochrane Library was conducted to identify studies containing comparison of cryoablation and PN. By utilizing those included studies, a systematic review and cumulative meta-analyses were performed to assess the safety and efficacy between cryoablation and PN for T1 renal masses.

Results: 17 retrospective studies providing available data were included in our study. Significant differences were found about all oncological variables including all-cause death, cancer-specific death, metastasis and local-recurrence (p < 0.001, p = 0.03, p < 0.001, and p < 0.001, respectively) between the PN group and the cryoablation group. The mean difference between two groups for percent estimated glomerular filtration rate decrease and creatinine increase was -4.84 and 0.15 respectively (p < 0.001 and p = 0.006, respectively). The incidences of overall and postoperative complications in the PN group were significantly higher than that in the cryoablation group (p = 0.001 and p < 0.001, respectively), but the result about intraoperative complications didn't show a significant difference between the two groups (p = 0.53).

Conclusions: Comparing with PN, cryoablation for clinical T1 renal tumors is associated with poorer oncological outcomes, but the existing disadvantages are accompanied by lower rate of overall and postoperative complications and superior renal functional preservation. For patients with imperative indications for nephron-sparing surgery who can't risk more invasive PN, cryoablation could be an attractive option. Owing to the inherent limitations of eligible studies, conclusions drawn from our meta-analyses should be interpreted cautiously and be confirmed further with well-designed randomized controlled trials with extensive follow-up length.

Partial nephrectomy versus ablative techniques for small renal masses: a systematic review and network meta-analysis

PURPOSE

To compare partial nephrectomy (PN), radiofrequency ablation (RFA), cryoablation (CRA) and microwave ablation (MWA) regarding oncologic, perioperative and functional outcomes.

MATERIAL AND METHODS

The MEDLINE, EMBASE and COCHRANE libraries were searched for studies comparing PN, RFA, CRA or MWA and reporting on any-cause or cancer-specific mortality, local recurrence, complications or renal function. Network meta-analyses were performed.

RESULTS

Forty-seven studies with 24,077 patients were included. Patients receiving RFA, CRA or MWA were older and had more comorbidities compared with PN. All-cause mortality was higher for CRA and RFA compared with PN (incidence rate ratio IRR = 2.58, IRR = 2.58, p < 0.001, respectively). No significant differences in cancer-specific mortality were evident. Local recurrence was higher for CRA, RFA and MWA compared with PN (IRR = 4.13, IRR = 1.79, IRR = 2.52, p < 0.05 respectively). A decline in renal function was less pronounced after RFA versus PN, CRA and MWA (mean difference in GFR MD = 6.49; MD = 5.82; MD = 10.89, p < 0.05 respectively).

CONCLUSION

Higher overall survival and local control of PN compared with ablative therapies did not translate into significantly better cancer-specific mortality. Most studies carried a high risk of bias by selecting younger and healthier patients for PN, which may drive superior survival and local control. Physicians should be aware of the lack of high-quality evidence and the potential benefits of ablative techniques for certain patients, including a superior complication profile and renal function preservation.

KEY POINTS

• Patients selected for ablation of small renal masses are older and have more comorbidities compared with those undergoing partial nephrectomy. • Partial nephrectomy yields lower all-cause mortality, which is probably biased by patient selection and does not translate into prolonged cancer-free survival. • The decline of renal function is smallest after radiofrequency ablation for small renal masses.

Partial Nephrectomy versus Thermal Ablation for Clinical Stage T1 Renal Masses: Systematic Review and Meta-Analysis of More than 3,900 Patients

PURPOSE

A systematic review and meta-analysis of clinical trials was undertaken to compare percutaneous thermal ablation versus partial nephrectomy (PN) for stage T1 renal tumors.

MATERIALS AND METHODS

A comprehensive search of major databases was conducted from October 2000 to July 2016. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. Incidences of all-cause mortality (ACM), cancer-specific mortality (CSM), local recurrence (LR), and metastases, as well as complication rates and changes in estimated glomerular filtration rate (eGFR), were evaluated.

RESULTS

Inclusion criteria were met by 15 of 961 papers. These studies represented 3,974 patients who had undergone an ablative procedure (cryoablation or radiofrequency ablation; n = 1,455; 37%) or PN (n = 2,519; 63%). ACM and CSM rates were higher for ablation than for PN (hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.54-2.87 [P < .05]; HR, 3.84; 95% CI, 1.66-8.88 [P < .05], respectively). No statistically significant difference in LR rate or risk of metastasis was seen between ablation and PN (HR, 1.32; 95% CI, 0.79-2.22 [P = .22]; HR, 1.83; 95% CI, 0.67-5.01 [P = 0.23], respectively). Complication rates were lower for ablation than for PN (13% vs 17.6%; odds ratio, 0.49; 95% CI, 0.25-0.94; P < .05). A significantly greater decrease in eGFR was observed after PN (13.09 mL/min/1.73 m²) vs ablation therapy (4.47 mL/min/1.73 m²).

CONCLUSIONS

Thermal ablation showed no significant difference in LR or metastases compared with PN. Thermal ablation was associated with a lower morbidity rate and a lesser reduction in eGFR compared with PN, but with higher ACM and CSM rates.

Focal ablation therapy for renal cancer in the era of active surveillance and minimally invasive partial nephrectomy

Partial nephrectomy is the optimal surgical approach in the management of small renal masses (SRMs). Focal ablation therapy has an established role in the modern management of SRMs, especially in elderly patients and those with comorbidities. Percutaneous ablation avoids general anaesthesia and laparoscopic ablation can avoid excessive dissection; hence, these techniques can be suitable for patients who are not ideal surgical candidates. Several ablation modalities exist, of which radiofrequency ablation and cryoablation are most widely applied and for which safety and oncological efficacy approach equivalency to partial nephrectomy. Data supporting efficacy and safety of ablation techniques continue to mature, but they originate in institutional case series that are confounded by cohort heterogeneity, selection bias, and lack of long-term follow-up periods. Image guidance and surveillance protocols after ablation vary and no consensus has been established. The importance of SRM biopsy, its optimal timing, the type of biopsy used, and its role in treatment selection continue to be debated. As safety data for active surveillance and experience with minimally invasive partial nephrectomy are expanding, the role of focal ablation therapy in the treatment of patients with SRMs requires continued evaluation.

[Ablative therapy in kidney cancer: Oncological, functional, perioperative outcomes and cost]

INTRODUCTION

The incidence of kidney cancer has increased significantly over the past few decades presumably due to the increased use of imaging. The aim of this article is to describe contemporary outcomes of ablative therapy and to compare them to other therapeutic options in terms of oncological, functional, perioperative outcomes and cost.

MATERIAL AND METHODS

We searched MEDLINE^®, Embase^®, using (MeSH) words; from January 2005 through May 2017, and we looked for all the studies. Investigators graded the strength of evidence in terms of methodology, language and relevance.

RESULTS

Ninety-one articles were analyzed. We described the outcomes of ablative therapy in relation to the energy used and the approach, and compared these outcomes to the other therapeutic options in terms of oncological, functional and perioperative outcomes. We analyzed these studies in order to search for predictive factors influencing the results of ablative therapy. We also analyzed the economic burden of small renal tumor management.

CONCLUSION

The strength of evidence is based almost entirely on retrospective studies and is susceptible to the inherent limitations of this study design. Although, the evidence was low among studies, our revue showed that, in elderly patients treated with ablative therapy for cT1a tumors, the cancer-specific survival was comparable to partial nephrectomy with differences in overall survival that are explained by competing risks of death in the old population. Considering the functional results, the renal function preservation seems to be comparable between the 2 groups while the perioperative morbidity is higher in the partial nephrectomy group. The evidence base medicine at this time cannot support the extension of the indications of ablative therapy beyond the actual implementations.

Renal Cell Carcinoma: Alternative Nephron-Sparing Treatment Options for Small Renal Masses, a Systematic Review

BACKGROUND

The standard treatment of T1 renal cell carcinoma (RCC) is (partial) nephrectomy. For patients where surgery is not the treatment of choice, for example in the elderly, in case of severe comorbidity, inoperability, or refusal of surgery, alternative treatment options are available. These treatment options include active surveillance (AS), radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), or stereotactic body radiotherapy (SBRT). In the present overview, the efficacy, safety, and outcome of these different options are summarized, particularly focusing on recent developments.

MATERIALS AND METHODS

Databases of MEDLINE (through PubMed), EMBASE, and the Cochrane Library were systematically searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The search was performed in December 2016, and included a search period from 2010 to 2016. The terms and synonyms used were renal cell carcinoma, active surveillance, radiofrequency ablation, microwave ablation, cryoablation and stereotactic body radiotherapy.

RESULTS

The database search identified 2806 records, in total 73 articles were included to assess the rationale and clinical evidence of alternative treatment modalities for small renal masses. The methodological quality of the included articles varied between level 2b and level 4.

CONCLUSION

Alternative treatment modalities, such as AS, RFA, CA, MWA, and SBRT, are treatment options especially for those patients who are unfit to undergo an invasive treatment. There are no randomized controlled trials available comparing surgery and less invasive modalities, leading to a low quality on the reported articles. A case-controlled registry might be an alternative to compare outcomes of noninvasive treatment modalities in the future.

[Focal therapy for small renal masses : Observation, ablation or surgery]

BACKGROUND

The rising incidence of renal cell carcinoma, its more frequent early detection (stage T1a) and the increasing prevalence of chronic renal failure with higher morbidity and shorter life expectancy underscore the need for multimodal focal nephron-sparing therapy.

DISCUSSION

During the past decade, the gold standard shifted from radical to partial nephrectomy. Depending on the surgeon's experience, the patient's constitution and the tumor's location, the intervention can be performed laparoscopically with the corresponding advantages of lower invasiveness. A treatment alternative can be advantageous for selected patients with high morbidity and/or an increased risk of complications associated with anesthesia or surgery. Corresponding risk stratification necessitates previous confirmation of the small renal mass (cT1a) by histological examination of biopsy samples. Active surveillance represents a controlled delay in the initiation of treatment.

RESULTS

Percutaneous radiofrequency ablation (RFA) and laparoscopic cryoablation are currently the most common treatment alternatives, although there are limitations particularly for renal tumors located centrally near the hilum. More recent ablation procedures such as high intensity focused ultrasound (HIFU), irreversible electroporation, microwave ablation, percutaneous stereotactic ablative radiotherapy and high-dose brachytherapy have high potential in some cases but are currently regarded as experimental for the treatment of renal cell carcinoma.

Renal Functional Outcomes after Surgery, Ablation, and Active Surveillance of Localized Renal Tumors: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Management strategies for localized renal masses suspicious for renal cell carcinoma include radical nephrectomy, partial nephrectomy, thermal ablation, and active surveillance. Given favorable survival outcomes across strategies, renal preservation is often of paramount concern. To inform clinical decision making, we performed a systematic review and meta-analysis of studies comparing renal functional outcomes for radical nephrectomy, partial nephrectomy, thermal ablation, and active surveillance.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1997 to May 1, 2015 to identify comparative studies reporting renal functional outcomes. Meta-analyses were performed for change in eGFR, incidence of CKD, and AKI.

RESULTS

We found 58 articles reporting on relevant renal functional outcomes. Meta-analyses showed that final eGFR fell 10.5 ml/min per 1.73 m2 lower for radical nephrectomy compared with partial nephrectomy and indicated higher risk of CKD stage 3 or worse (relative risk, 2.56; 95% confidence interval, 1.97 to 3.32) and ESRD for radical nephrectomy compared with partial nephrectomy. Overall risk of AKI was similar for radical nephrectomy and partial nephrectomy, but studies suggested higher risk for radical nephrectomy among T1a tumors (relative risk, 1.37; 95% confidence interval, 1.13 to 1.66). In general, similar findings of worse renal function for radical nephrectomy compared with thermal ablation and active surveillance were observed. No differences in renal functional outcomes were observed for partial nephrectomy versus thermal ablation. The overall rate of ESRD was low among all management strategies (0.4%-2.8%).

CONCLUSIONS

Renal functional implications varied across management strategies for localized renal masses, with worse postoperative renal function for patients undergoing radical nephrectomy compared with other strategies and similar outcomes for partial nephrectomy and thermal ablation. Further attention is needed to quantify the changes in renal function associated with active surveillance and nephron-sparing approaches for patients with preexisting CKD.

Ablative Therapy for Small Renal Masses

The management of small renal masses has become an important public health topic. The increased use of cross-sectional imaging and ultrasound has led to a downward stage migration for the detection of small renal masses. Cancer-specific survival, however, has not reflected this trend accordingly. Although partial nephrectomy has been the mainstay of treatment of small renal masses less than 4 cm, there is growing interest in ablative therapies, such as cryoablation and radiofrequency ablation, due to decreased morbidity. Oncologic outcomes are limited by methodology and length of follow-up, but short-term recurrence rates are low.

Multipoint Thermal Sensors Associated with Improved Oncologic Outcomes Following Cryoablation

INTRODUCTION

Cryoablation (CA) is a minimally invasive modality for the management of small renal cortical neoplasms (RCN). Effective ablation is dependent on achieving target temperatures during CA that result in tumor cell death. We investigated long-term oncologic outcomes following CA using multipoint thermal sensors (MTS), which allow precise temperature determination at four points along the needle.

METHODS

We performed a retrospective review of 20 patients with <4 cm RCN who underwent de novo CA from 2005 to 2009. In 11 procedures, MTS needles were deployed with the goal of obtaining -20°C at the tumor margin, while 9 were done without MTS. Patient demographics, tumor characteristics, and CA procedure data were retrieved and analyzed. Follow-up CT or MRI was used to assess recurrence status.

RESULTS

With a mean follow-up of 45 months, none of the 11 patients experienced a recurrence in the MTS group, compared with 4 of 9 (44.4%) patients in the non-MTS group (p = 0.026). Of the biopsy-confirmed renal cancers, none of the 6 in the MTS group, compared with 3 of 6 (50%) in the non-MTS group, recurred (p = 0.182). Age, tumor size, surgical approach, tumor histopathology, grade, follow-up time, and skin-to-tumor distance were similar between the MTS and non-MTS groups. The MTS group was also associated with increased total length of freeze (p = 0.041), procedure time (p = 0.020), cryoprobe utilization (p = 0.049), and a greater ratio of cryoprobes used per cm diameter of tumor (p = 0.003).

CONCLUSIONS

In this small renal mass pilot study, the use of MTS needles to monitor temperature and guide cryoneedle deployment was associated with improved oncologic outcomes.

Small renal masses in the elderly: Contemporary treatment approaches and comparative oncological outcomes of nonsurgical and surgical strategies

Over the last decades, there has been a significant stage migration in renal cell carcinoma and especially older patients are getting diagnosed more frequently with low stage disease, such as small renal masses ≤4 cm of size. Considering the particular risk profile of an older population, often presenting with a nonnegligible comorbidity profile and progressive renal dysfunction, treatment approaches beyond aggressive radical surgical procedures have come to the fore. We sought to give a contemporary overview of the available different treatment strategies for incidental small renal masses in an elderly population with the focus on comparative oncological outcomes of nonsurgical and surgical modalities.

Minimally Invasive Partial Nephrectomy Versus Laparoscopic Cryoablation for Patients Newly Diagnosed with a Single Small Renal Mass

BACKGROUND

Minimally invasive partial nephrectomy (MIPN) and laparoscopic renal cryoablation (LRC) are two treatment options increasingly used for small renal masses.

OBJECTIVE

To compare perioperative, oncologic, and functional outcomes after MIPN and LRC.

DESIGN, SETTING, AND PARTICIPANTS

We included 372 consecutive patients newly diagnosed with a single small renal mass and treated with either MIPN or LRC at a single institution.

INTERVENTION

MIPN and LRC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Regression models were used to evaluate the impact of surgical treatment (MIPN vs LRC) on perioperative, oncologic, and functional outcomes.

RESULTS AND LIMITATIONS

Overall, 206 patients (55%) underwent MIPN and 166 (45%) were treated with LRC. In multivariate analysis, the rate of postoperative complications was significantly lower in the MIPN compared to the LRC group (20% vs 28%; adjusted difference -11%; p=0.02) after adjusting for age at surgery, American Society of Anesthesiologists score (1 vs 2 vs 3), and tumor size. The median follow-up was similar in the two groups (43 and 39 mo for MIPN and LRC, respectively). In univariate Cox regression analysis, treatment type was not significantly associated with disease-free survival (hazard ratio 1.06, 95% confidence interval [CI] 0.45-2.52; p=0.9). The disease-free survival rate at 5 yr was 92% in MIPN and 93% in LRC patients. In multivariate linear regression analysis, LRC was significantly associated with a higher estimated glomerular filtration rate (eGFR) at 6 mo compared to MIPN (coefficient 4.68, 95% CI 0.06-9.30; p=0.047) after adjusting for age at surgery, tumor size, and preoperative eGFR. There was no significant association between surgical treatment and postoperative eGFR at 3 yr after surgery (coefficient -2.36, 95% CI -7.55 to 2.83; p=0.4). Limitations include the retrospective study design and selection bias.

CONCLUSIONS

MIPN and LRC provided similar cancer control and comparable renal function at intermediate-term follow-up. Both surgical techniques emerged as viable treatment options for patient newly diagnosed with a single small renal mass. Further multi-institutional studies with longer follow-up and nephrometry scores are needed to corroborate our findings.

PATIENT SUMMARY

In patients newly diagnosed with a single small renal mass, minimally invasive partial nephrectomy and laparoscopic renal cryoablation provided similar cancer control and comparable renal function at intermediate-term follow-up.

Safety and Efficacy of Thermal Ablation for Small Renal Masses in Solitary Kidney: Evidence from Meta-Analysis of Comparative Studies

Objective

To evaluate comparative renal functional preservation, perioperative and oncologic outcomes, and complications of thermal ablation (TA) versus partial nephrectomy (PN) in management of Small renal masses (SRMs) in solitary kidney.

Methods and Findings

Medline, Embase, Web of Science and the Cochrane Library were systematically searched. A meta-analysis for comparative studies comparing TA with PN was performed. According to predefined inclusion criteria, seven datasets were identified from 8 observational studies including a total of 628 patients. Cumulated data showed the changes of creatinine (p=0.02) and estimated glomerular filtration rate (eGFR) (p<0.0001) in TA arm were significantly less than these in PN arm. Significantly less new-set chronic kidney disease (CKD) was observed in TA group (p=0.04). In terms of postoperative dialysis rate, the difference favoring TA was also noted, though there is no statistical significance (p=0.09). With regard to perioperative outcomes, our data demonstrated that patients who underwent TA had significantly shorter operation time (p=0.002), less blood loss (p<0.0001), shorter length of stay (p<0.00001), and less transfusion rate (p=0.01) than those underwent PN. In addition, patients underwent TA suffered less intra- and postoperative complications (p=0.007, p<0.00001; respectively). With regard to oncologic outcomes, disease-free survival (DFS) (p<0.00001) and cancer-specific survival (CSS) (p=0.01) in the PN arm were significantly better than these of the TA arm. But, TA yielded a comparable overall survival to PN (p=0.40). Sensitivity analyses led to very similar results with overall results, and confirmed its stability.

Conclusions

Our analysis indicates that PN have advantage in controlling cancer recurrence. However, TA is associated with significantly better renal functional preservation and perioperative outcomes, and less complications without increasing overall death. Our data suggest that indication for TA may be extended to select younger, healthier patients who desire a much less invasive therapeutic option.

Current status of cryotherapy for prostate and kidney cancer

In terms of treating diseases, minimally invasive treatment has become a key element in reducing perioperative complications. Among the various minimally invasive treatments, cryotherapy is often used in urology to treat various types of cancers, especially prostate cancer and renal cancer. In prostate cancer, the increased incidence of low-risk, localized prostate cancer has made minimally invasive treatment modalities an attractive option. Focal cryotherapy for localized unilateral disease offers the added benefit of minimal morbidities. In renal cancer, owing to the increasing utilization of cross-sectional imaging, nearly 70% of newly detected renal masses are stage T1a, making them more susceptible to minimally invasive nephron-sparing therapies including laparoscopic and robotic partial nephrectomy and ablative therapies. This article reviews the various outcomes of cryotherapy compared with other treatments and the possible uses of cryotherapy in surgery.

Comparison between laparoscopic partial nephrectomy and laparoscopic ablation therapy: a meta-analysis

OBJECTIVE

To conduct a meta-analysis of the literature evaluating comparisons on the peri-operative and oncological outcomes between laparoscopic partial nephrectomy (LPN) and laparoscopic ablation therapy (LAT) in the treatment of small renal masses (SRMs).

MATERIAL AND METHODS

MEDLINE, EMBASE, Google Scholar, Cochrane Library, and CNKI were searched for clinical trials comparing LPN with LAT. Data of peri-operative and follow-up outcomes were extracted and compared. Publication bias was identified and sensitivity analysis was also performed.

RESULTS

Data from 11 studies including 928 patients (525 patients in the LPN group and 403 in the LAT group) were collected. Baseline characteristics were compared and differences were found in age, preoperative renal function and proportion of solitary kidney (p < 0.05 respectively). For peri-operative outcomes, the LPN group had greater estimated blood loss, longer operative duration and length of hospital stay, and more peri-operative complications (p < 0.05, respectively). The LAT group had a significantly higher local recurrence (p < 0.05). There was no significant difference in postoperative change of renal function (p = 0.21).

CONCLUSION

In comparison with LPN, LAT provides better peri-operative outcomes, but a higher local recurrence rate. LAT does not seem to provide an obvious advantage in protecting renal function. Further clinical trials with randomized design and long-term follow-up are needed.

Nephron sparing surgery for De Novo kidney graft tumor: results from a multicenter national study

Nephron sparing surgery (NSS) results in the transplanted population remain unknown because they are only presented in small series or case reports. Our objective was to study renal sparing surgery for kidney graft renal cell carcinomas (RCC) in a multicenter cohort. Data were collected from 32 French transplantation centers. Cases of renal graft de novo tumors treated as RCC since the beginning of their transplantation activity were included. Seventy-nine allograft kidney de novo tumors were diagnosed. Forty-three patients (54.4%) underwent renal sparing surgery. Mean age of grafted kidneys at the time of diagnosis was 47.5 years old (26.1-72.6). The mean time between transplantation and tumor diagnosis was 142.6 months (12.2-300). Fifteen tumors were clear cell carcinomas (34.9%), and 25 (58.1%) were papillary carcinomas. Respectively, 10 (24.4%), 24 (58.3%) and 8 (19.5%) tumors were Fuhrman grade 1, 2 and 3. Nine patients had postoperative complications (20.9%) including four requiring surgery (Clavien IIIb). At the last follow-up, 41 patients had a functional kidney graft, without dialysis and no long-term complications. NSS is safe and appropriate for all small tumors of transplanted kidneys with good long-term functional and oncological outcomes, which prevent patients from returning to dialysis.

Robotic nephron-sparing surgery for renal tumors: Current status

There have been a number of advances in robotic partial nephrectomy (RPN) for renal masses. We reviewed these advances with emphasis on the evolution of technique and outcomes as well as the expanding indications for RPN. Literature in the English language was reviewed using the National Library of Medicine database. Relevant articles were extracted, and their citations were utilized to broaden our search. The identified articles were reviewed and summarized with a focus on novel developments. RPN is an evolving procedure and is an emerging viable alternative to laparoscopic partial nephrectomy and open partial nephrectomy with favorable outcomes. The contemporary techniques used for RPN demonstrate excellent perioperative outcomes. The short-term oncologic outcomes are comparable to those of laparoscopic and open surgical approaches. Further studies are needed to assess long-term oncologic control.

Laparoscopic renal cryoablation

In light of evidence linking radical nephrectomy and consequent suboptimal renal function to adverse cardiovascular events and increased mortality, research into nephron-sparing techniques for renal masses widely expanded in the past two decades. The American Urological Association (AUA) guidelines now explicitly list partial nephrectomy as the standard of care for the management of T1a renal tumors. Because of the increasing utilization of cross-sectional imaging, up to 70% of newly detected renal masses are stage T1a, making them more amenable to minimally invasive nephron-sparing therapies including laparoscopic and robotic partial nephrectomy and ablative therapies. Cryosurgery has emerged as a leading option for renal ablation, and compared with surgical techniques it offers benefits in preserving renal function with fewer complications, shorter hospitalization times, and allows for quicker convalescence. A mature dataset exists at this time, with intermediate and long-term follow-up data available. Cryosurgical recommendations as a first-line therapy are made at this time in limited populations, including elderly patients, patients with multiple comorbidities, and those with a solitary kidney. As more data emerge on oncologic efficacy, and technical experience and the technology continue to improve, the application of this modality will likely be extended in future treatment guidelines.

The contemporary role of ablative treatment approaches in the management of renal cell carcinoma (RCC): focus on radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFU), and cryoablation

INTRODUCTION

Currently, most of renal tumors are small, low grade, with a slow growth rate, a low metastatic potential, and with up to 30 % of these tumors being benign on the final pathology. Moreover, they are often diagnosed in elderly patients with preexisting medical comorbidities in whom the underlying medical conditions may pose a greater risk of death than the small renal mass. Concerns regarding overdiagnosis and overtreatment of patients with indolent small renal tumors have led to an increasing interest in minimally invasive, ablative as an alternative to extirpative interventions for selected patients.

OBJECTIVE

To provide an overview about the state of the art in radiofrequency ablation (RFA), high-intensity focused ultrasound, and cryoablation in the clinical management of renal cell carcinoma.

METHODS

A PubMed wide the literature search of was conducted.

RESULTS

International consensus panels recommend ablative techniques in patients who are unfit for surgery, who are not considered candidates for or elect against elective surveillance, and who have small renal masses. The most often used techniques are cryoablation and RFA. These ablative techniques offer potentially curative outcomes while conferring several advantages over extirpative surgery, including improved patient procedural tolerance, faster recovery, preservation of renal function, and reduction in the risk of intraoperative and postsurgical complications. While it is likely that outcomes associated with ablative modalities will improve with further advances in technology, their application will expand to more elective indications as longer-term efficacy data become available.

CONCLUSION

Ablative techniques pose a valid treatment option in selected patients.

Partial nephrectomy--contemporary indications, techniques and outcomes

Increased detection of the small renal mass over the last two decades has led to greater utilization of partial nephrectomy techniques. Appreciation of the negative impact of chronic renal impairment has resulted in partial nephrectomy surpassing radical nephrectomy as the preferred treatment for technically feasible lesions. Indeed the management of localized renal tumours has become focused on techniques that maximally preserve nephron quantity and quality, and therefore maximize renal function after surgery. Postoperative renal function is determined primarily by three factors: preoperative renal function, volume of renal mass preserved and surgical renal ischaemia. Minimization of surgical ischaemia is achieved by early unclamping and unclamped (zero ischaemia) techniques. In addition, laparoscopic and robotic approaches to nephron-sparing surgery have significantly reduced the morbidity of the partial nephrectomy procedure compared with the traditional open approach. The contemporary techniques used for partial nephrectomy demonstrate excellent renal functional and oncological outcomes and minimize perioperative complications.

Evaluation of robotic and laparoscopic partial nephrectomy for small renal tumours (T1a)

OBJECTIVE

To compare laparoscopic partial nephrectomy (LPN) with robotic PN (RPN) using meta-analytical techniques, since there has been a rise in the incidence of small renal masses (SRM; <4 cm) minimally invasive approaches are becoming more popular in dealing with such pathologies.

MATERIALS AND METHODS

A systematic review of the literature was performed to identify studies comparing LPN and RPN. Comparative studies evaluating RPN and LPN that fulfilled the inclusion criteria were selected. Data on preoperative, operative (operative time, estimated blood loss [EBL], and warm ischaemia time [WIT]), postoperative (length of stay [LOS]) variables and complications were collected. A meta-analysis using random effect model was performed. A further Bland-Altman analysis of some of the operative variables was done to compare their reproducibility and mean difference in techniques.

RESULTS

Six studies matched the selection criteria. In all, 256 patients were analysed (40% RPN and 60% LPN). There was no significant different in EBL (P = 0.12, 95% confidence interval [CI] -12.01 to 104.26). Similarly, there was no significant different in WIT between the groups (P = 0.23, 95% CI -15.22 to 3.70). Also, LOS (P = 0.22, 95% CI -0.38 to 0.09) and overall postoperative complication rates were not significantly different between the groups (P = 0.84, 95% CI -0.05 to 0.06).

CONCLUSIONS

Despite multiple studies reporting better perioperative variables for RPN, the present study found no significant differences between RPN and LPN. This has implications for both the surgeon and the patient. Lack of randomised controlled trials in addition to a lack of long-term oncological data for RPN are current limitations.

Current management options for the small renal mass in a solitary kidney

The widespread use of cross-sectional imaging has resulted in an increase in the frequency of incidentally identified small renal masses (SRMs). With high cancer-specific survival rates following radical nephrectomy, there is an increasing patient cohort at risk of developing a metachronous contralateral tumour. Nephron-sparing surgery (NSS) has been shown to reduce progression of chronic kidney disease, being the impetus to utilize NSS for the management of SRMs in an anatomical or functional solitary kidney. At present, open partial nephrectomy is the gold standard treatment for an SRM in a solitary kidney; however, there are a number of other minimally invasive options, including laparoscopic partial nephrectomy, and in situ ablative procedures. In addition, variables such as warm and cold ischaemia and renal vascular clamping have been shown to affect outcomes. In this review, we summarize contemporary management options focusing specifically on oncological and functional outcomes.