LONG-TERM RESULTS OF NEPHRON SPARING SURGERY FOR LOCALIZED RENAL CELL CARCINOMA: 10-YEAR FOLLOWUP

Correlation Between BMI and Kidney Tumor Lateralization: Insights into Survival and Risk Factors

Background: Kidney cancer accounts for approximately 2% of all diagnosed cancers and fatalities worldwide, and a notable increase in its incidence has been observed in recent years. Previous studies have identified various risk factors for renal cell carcinoma (RCC), including age, gender, smoking, hypertension, overweight, and obesity. However, limited information is available regarding the correlation between RCC risk factors and tumor lateralization. Objectives: To investigate the relationship between body mass index (BMI) and the lateralization of kidney tumors in patients undergoing surgery for renal cell carcinoma. Moreover, we aim to evaluate the impact of lateralization of malignant kidney tumors on overall survival (OS) and cancer-specific survival (CSS). Materials and Methods: This single-center study included 287 patients who underwent surgical treatment for kidney tumors between January 2016 and December 2019. The patients were allocated into the following groups based on their BMI: normal (18.5-24.99 kg/m2), overweight (25-29.99 kg/m2), or obese (≥30 kg/m2). The study collected demographic and histopathological data, as well as patient history, including risk factors such as smoking and hypertension. Results: Right-sided kidney tumors occurred more frequently (55.05%, n = 158) than left-sided ones (44.95%, n = 129). A statistically significant relationship (p = 0.04731) was observed between BMI and the frequency of right-sided kidney tumors in the overweight group (70 vs. 43 cases). There was no correlation between BMI and the occurrence of kidney tumors in the normal BMI and obesity groups. Furthermore, the analysis revealed no association between the lateralization of kidney tumors, smoking, and hypertension. The 5-year survival rate was 62%, with a mean follow-up duration of 104 months (approximately 8.5 years). No statistically significant difference was observed between the right- and left-sided cancer groups, with survival rates of 58% and 66%, respectively (p = 0.652). Conclusions: This study highlighted that right-sided kidney tumors occurred significantly more frequently in overweight individuals in our cohort of patients. No association was observed between lateralization of kidney cancer and overall survival (OS) or cancer-specific survival (CSS).

Long-term consequences of positive surgical margin after partial nephrectomy for renal cell carcinoma: multi-institutional analysis

INTRODUCTION

The aim of the study was to determine the impact of positive surgical margins (PSM) after PN on very long-term recurrence in a contemporary cohort.

METHODS

Patients who underwent PN for a localized renal tumour were included. Patients were stratified according to the presence of PSM. Data on patients' characteristics, the tumour, the peri- and postoperative events were collected. Disease-free survival (DFS) and overall survival (OS) were assessed by the Kaplan-Meier method and compared by the log-rank test. Sensitivity analyses using weighted propensity score analysis was performed to account for potential selection biases arising from the nonrandom allocation of patients to different groups.

RESULTS

A total of 1115 patients were included in the study. The incidence of PSM was 5.4% (n = 61). The median follow-up time was 51 months for the PSM group and 61 months for the NSM group (p = 0.31). Recurrence rates were significantly higher in the PSM group (13%, n = 8) compared to the NSM group (7%, n = 73) (p = 0.05). This resulted in a significant reduction in DFS in the PSM group (p = 0.004), particularly pronounced in patients with clear cell renal cell carcinoma. Additionally, OS was significantly lower in the PSM group (p < 0.01). Propensity score analysis confirmed a decrease in DFS for the PSM group (p = 0.05), while there was no significant difference in OS between the two groups (p = 0.49).

CONCLUSION

In this retrospective multicenter study, PSM impact on oncological outcomes, increasing recurrence, but no difference in OS was observed post-adjustment for biases.

Tracing the evolving dynamics and research hotspots in the kidney neoplasm and nephron sparing surgery field from the past to the new era

BACKGROUND

With increasing detection of small renal masses and accumulating evidence that nephron sparing surgery (NSS) could achieve oncological equivalence and functional superiority compared with radical nephrectomy (RN), NSS has become first-line therapy for some patients with localized renal masses.

OBJECTIVE

This study aims to review the publications in the kidney neoplasm and NSS field, exploring the research hotspots.

METHOD

Kidney neoplasm and NSS related publications before July 3th 2023 were obtained from the Web of Science Core Collection database. We then used bibliometric analysis to conduct performance analysis, citation analysis and co-citation network of publications, together with keyword co-occurrence analysis.

RESULTS

Seven thousand five hundred and sixty-four documents were finally retrieved, and the annual publications increased exponentially. The most productive authors were "KAOUK JH" and "GILL IS", while USA, and 12 American affiliations such as CLEVELAND CLINIC FOUNDATION and MAYO CLINIC were far leading in this field. Journal of Urology and European Urology were journals with the highest citations and h-index.

DISCUSSION

Through literature reviewing plus co-occurrence and clustering analysis, the therapeutic effects of partial nephrectomy (PN) versus RN on patients with localized renal cell carcinoma, different operative approaches of PN, and conservative NSS methods were deemed as the most focused topics.

CONCLUSION

Three aspects were the most important hotspots in this field. Firstly, how to provide the optimal management choices for different patients. Secondly, therapeutic effects of different management options and surgical techniques needed more prospective and randomized studies. Finally, more novel technologies and surgical techniques were required.

Optimizing the kidney donor pool: transplanting donor kidneys after partial nephrectomy of masses or cysts

Background

A limiting factor in expanding the kidney donor pool is donor kidneys with renal tumors or cysts. Partial nephrectomy (PN) to remove these lesions prior to transplantation may help optimize organ usage without recurrence of malignancy or increased risk of complications.

Methods

We retrospectively analyzed all recipients of a living or deceased donor graft between February 2009 and October 2022 in which a PN was performed prior to transplant due to the presence of one or more concerning growths. Donor and recipient demographics, perioperative data, donor allograft pathology, and recipient outcomes were obtained.

Results

Thirty-six recipients received a graft in which a PN was performed to remove suspicious masses or cysts prior to transplant. Majority of pathologies turned out to be a simple renal cyst (65%), followed by renal cell carcinoma (15%), benign multilocular cystic renal neoplasm (7.5%), angiomyolipoma (5%), benign renal tissue (5%), and papillary adenoma (2.5%). No renal malignancy recurrences were observed during the study period (median follow-up: 67.2 months). Fourteen complications occurred among 11 patients (30.6% overall) during the first 6mo post-transplant. Mean eGFR (± standard error) at 36 months post-transplant was 51.9 ± 4.2 ml/min/1.73 m2 (N = 23). Three death-censored graft losses and four deaths with a functioning graft and were observed.

Conclusion

PN of renal grafts with suspicious looking masses or cysts is a safe option to optimize organ usage and decrease the kidney non-use rate, with no observed recurrence of malignancy or increased risk of complications.

Comparing Perioperative Complications of Off-Clamp versus On-Clamp Partial Nephrectomy for Renal Cancer Using a Novel Energy Balancing Weights Method

Partial nephrectomy (PN) is the primary surgical method for renal tumor treatment, typically involving clamping the renal artery during tumor removal, leading to warm ischemia and potential renal function impairment. Off-clamp approaches have been explored to mitigate organ damage, yet few results have emerged about the possible effects on hemoglobin loss. Most evidence comes from retrospective studies using propensity score matching, known to be sensitive to PS model misspecification. The energy balancing weights (EBW) method offers an alternative method to address bias by focusing on balancing all the characteristics of covariate distribution. We aimed to compare on- vs. off-clamp techniques in PN using EB-weighted retrospective patient data. Out of 333 consecutive PNs (275/58 on/off-clamp ratio), the EBW method achieved balanced variables, notably tumor anatomy and staging. No significant differences were observed in the operative endpoints between on- and off-clamp techniques, although off-clamp PNs showed slight reductions in hemoglobin loss and renal function decline, albeit with slightly higher perioperative blood loss. Our findings support previous evidence, indicating comparable surgical outcomes between standard and off-clamp procedures, with the EBW method proving effective in balancing baseline variables in observational studies comparing interventions.

Oncological and functional outcomes of patients who underwent open partial nephrectomy for kidney tumor

OBJECTIVE

To report long-term functional and oncological outcomes of OPN Methods: We enrolled 182 patients who underwent consecutive OPN with a diagnosis of kidney tumor in our clinic between April 2002 and February 2020 and were selected from our prospective OPN database. Preoperative demographic and clinical characteristics, intraoperative and pathological results, and patients' postoperative functional and oncological follow-up data were retrospectively analyzed. Overall survival (OS) and disease- free survival (DFS) were evaluated using Kaplan-Meier survival analysis. The time-dependent variation between preoperative and postoperative functional results was statistically analyzed and presented in a graph.

RESULTS AND LIMITATIONS

The mean age was 54.4 ± 10.8 yr, and the median age-adjusted Charlson comorbidity index (ACCI) was 1 (interquartile range [IQR] 0-1). The mean tumor size was 3.1 ± 1.2 cm, and the median RENAL score was 6 (IQR 5-8). The most common malign histopathological subtype was clear cell carcinoma with 76.6%, and five cases (3.4%) had positive surgical margins (PSMs). The most common surgical techniques were the retroperitoneal approach (98.9%) and cold ischemia (88.5%). Estimated glomerular filtration rate (eGFR) preservation was 92% (80.8-99.3, IQR), which translates to 32% chronic kidney disease (CKD) upstaging. Acute kidney injury (AKI) was detected in 27 (14.8%) patients according to RIFLE criteria. The intraoperative complication rate was 5.5%, and the postoperative overall complication rate (Clavien-Dindo 1-5) was 30.2%. Major complications (Clavien-Dindo 3-5) were observed in 13 (7.1%) patients. The median oncological follow-up was 42 mo (21.3- 84.6, IQR), and the 5- and 10-yr OS were 90.1% and 78.6%, 5 and 10-yr DFS were 99.4% and 92.1%, respectively. No local recurrence was observed in 5 (3.4%) patients with PSMs; only one had distant metastasis in the 8th postoperative month. The retrospective design, the small number of patients who underwent PN based on mandatory indication, and one type of surgical approach may limit the generalizability of our findings.

CONCLUSIONS

This study confirms excellent long-term oncologic and functional outcomes after OPN in a cohort of patients selected from a single institution. In light of the information provided by the literature and our study, our recommendation is to push the limits of PN under every technically feasible condition in the treatment of kidney tumors to protect the kidney reserve and achieve near-perfect oncological results.

Feasibility study of a novel robotic system for transperitoneal partial nephrectomy: An in vivo experimental animal study

PURPOSE

To evaluate the safety and feasibility of partial nephrectomy with the use of the novel robotic system in an in vivo animal model.

METHODS

Right partial nephrectomy was performed in female pigs by a surgical team consisting of one surgeon and one bedside assistant. Both were experienced in laparoscopic surgery and trained in the use of the novel robotic system. The partial nephrectomies were performed using four trocars (three trocars for the robotic arms and one as an assistant trocar). The completion of the operations, set-up time, operation time, warm ischemia time (WIT) and complication events were recorded. The decrease in all variables between the first and last operation was calculated.

RESULTS

In total, eight partial nephrectomies were performed in eight female pigs. All operations were successfully completed. The median set-up time was 19.5 (range, 15-30) minutes, while the estimated median operative time was 80.5 minutes (range, 59-114). The median WIT was 23.5 minutes (range, 17-32) and intra- or postoperative complications were not observed. All variables decreased in consecutive operations. More precisely, the decrease in the set-up time was calculated to 15 minutes between the first and third attempts. The operative time was reduced by 55 minutes between the first and last operation, while the WIT was decreased by 15 minutes during the consecutive attempts. No complications were noticed in any operation.

CONCLUSIONS

Using the newly introduced robotic system, all the advantages of robotic surgery are optimized and incorporated, and partial nephrectomies can be performed in a safe and effective manner.

Insufflation via a peritoneal dialysis catheter is a safe way to achieve pneumoperitoneum: a case report

A 66-year-old female with a preoperative high index hostile abdomen was incidentally found to have a right T1a 16 mm renal cell carcinoma mass. She safely underwent robot assisted partial nephrectomy after her peritoneal dialysis catheter was alternatively used for insufflation. This adjustment in technique reduced risk related morbidity and possible conversion to open laparotomy.

Adverse pathologic features impact survival outcomes for small renal masses following nephrectomy

PURPOSE

While most small renal masses (SRM) < 4 cm have an excellent prognosis following resection, the impact of adverse T3a pathologic features on oncologic outcomes of SRMs remains unclear. We sought to compare clinical outcomes for surgically resected pT3a versus pT1a SRMs at our institution.

MATERIALS AND METHODS

We retrospectively reviewed records of patients who underwent radical or partial nephrectomy (RN, PN) for renal tumors <4 cm at our institution between 2010 and 2020. We compared features and outcomes of pT3a vs pT1a SRMs. Continuous and categorical variables were compared using Student's t and Pearson's chi-squared tests, respectively. Postoperative outcomes of interest including overall, cancer-specific, and recurrence-free survival (OS, CSS, and RFS) were analyzed using Kaplan-Meier method, Cox proportional hazard regression, and competing risk analysis. Analyses were performed using R statistical package (R Foundation, v4.0).

RESULTS

We identified 1,837 patients with malignant SRMs. Predictors of postoperative pT3a upstaging included higher renal score, larger tumor size, and presence of radiologic features concerning for T3a disease (odds ratio [OR] = 5.45, 95% confidence interval [CI] 3.92-7.59, P < 0.001). On univariable modeling, pT3a SRMs had higher positive margin rates (9.6% vs 4.1%, P < 0.001), worse OS (hazard ratio [HR] = 2.9, 95% CI 1.6-5.3, P = 0.002), RFS (HR 9.32, 95% CI 2-40.1, P = 0.003), and CSS (HR = 3.6, 95% CI 1.5-8.2, P = 0.003). On multivariable modeling, pT3a status remained associated with worse RFS (HR = 2.7, 95% CI 1.04-7, P = 0.04), but not OS (HR 1.6, 95% CI = 0.83-3.1, P = 0.2); multivariable modeling was deferred for CSS due to low event rates.

CONCLUSIONS

Adverse T3a pathologic features portend worse outcomes for SRMs, highlighting the crucial role of pre-operative planning and case selection. These patients have relatively poor prognosis, and should be monitored more closely and counseled for consideration of adjuvant therapy or clinical trials.

Evaluation of the safety of retroperitoneal laparoscopic partial nephrectomy by investigating the perioperative indicators

Background

In recent years, open nephron sparing partial nephrectomy (OPN) has been gradually applied and generally accepted. Recent statistical data show that PN not only can safely and effectively preserve the functional nephron, but also has fewer complications, low local recurrence rate and no significant difference in long-term survival rate compared with nephrectomy/radical nephrectomy, which has gradually become a routine treatment for small renal cell carcinoma. Therefore, how to maximize the protection of postoperative residual renal function (RRF) and reduce the risk of CKD while achieving the ideal local and overall tumor control effect is the key to the treatment of renal cancer, and is also the focus of attention of urologists and nephrologists.

Objective

To evaluate the safety of retroperitoneal laparoscopic partial nephrectomy (RLPN) by investigating the perioperative indicators and postoperative follow-up.

Methods

A total of 40 hospitalized patients in our hospital from December 2019 to December 2021 were selected and followed up for a long time. Patients with renal tumors less than 4cm in diameter and exogeneous or partial exogeneity were randomly divided into 2 groups. Patients in retroperitoneal laparoscopic group (n = 20) were treated with nephron sparing partial nephrectomy (0.5-1cm). Twenty patients underwent retroperitoneal laparoscopic radical nephrectomy (LRN).The time of removal of drainage tube, drainage volume, time of feeding activity and postoperative hospital stay were recorded, and the safety of the operation was evaluated.

Results

nephron sparing partial nephrectomy is suitable for patients with localized renal carcinoma or benign tumor <4cm. RLPN can be applied to all indications of open nephron sparing partial nephrectomy (OPN), with good safety, and can preserve residual renal function to the greatest extent. The operative vascular occlusion time was controlled within 40 minutes, and the use of renal function protection measures during the operation was safe and controllable in reducing the prevention of warm ischemic kidney damage, with good safety. The renal tumor capsule with 0.5cm~1cm margin was complete by postoperative pathology. In the process of tumor resection and suture collection system in the RLPN group, we improved the previous operation of "resection before hemostasis" to "resection while hemostasis" and "knot-free suture" technology, which saved the operation time of intracavity suture knotting. Reduced cortical tear caused by vertical pull during knot tying. The combined effect of biological clip and hemostatic gauze can stimulate the granulation proliferation of renal cortical wound and accelerate the repair. With the combination of knot-free suture and renal segment vascular occlusion, hot ischemic kidney damage is reduced. In the RLPN group, there were no complications of urinary fistula and bleeding, and no abnormal changes in renal function during follow-up. The safety of RLPN group is worthy of affirmation.

Conclusion

The perioperative safety and short-term postoperative renal function recovery of RLPN are good, and the overall safety of this operation is worthy of affirmation.

Safety and Efficacy of Stereotactic Ablative Radiation Therapy for Renal Cell Cancer: 24-Month Results of the RSR1 Phase 1 Dose Escalation Study

PURPOSE

Stereotactic body radiation therapy (SBRT) has become a new therapeutic option for primary renal cell carcinoma. However, treatment doses lack consistency in the literature. The primary objective of this study was to determine the maximum tolerated dose for renal cancer SBRT.

METHODS AND MATERIALS

This phase 1 multicentric dose-escalation study assessed 4 dose levels: 8 Gy × 4, 8 Gy × 5, 10 Gy × 4, and 12 Gy × 4. The primary objective of this study was to determine the maximal tolerated dose, defined by the occurrence of dose-limiting toxicity was defined as any acute side effect of grade ≥4 based on the Common Terminology Criteria for Averse Events, version 4.0.

RESULTS

From October 2010 to September 2017, 13 patients were enrolled. The median follow-up was 23 months. There was no dose-limiting toxicity in our study, and the highest dose was reached successfully. No acute or late toxic effects above grade 2 were seen. There was no significant alteration of renal function after treatment. At 24 months, 2 patients had partial response and the others had stable disease.

CONCLUSIONS

After 24 months of follow-up, no dose-limiting toxicity was seen at any of the prescribed dose levels in our study. The findings suggest that our last dose level of 48 Gy in 4 12-Gy fractions can be considered safe and can be used in further studies.

Clinical Outcomes of Robotic Assisted Partial Nephrectomy for Pathologic T3a Renal Masses with Venous Tumor Thrombus

OBJECTIVE

To evaluate the safety, efficacy, and early oncologic outcomes of pT3a renal cell carcinoma (RCC) with venous involvement treated with robotic partial nephrectomy (RPN), given that experience and outcomes in this group is limited.

METHODS

A retrospective chart review of patients undergoing RPN from 9/2009-7/2020 was performed. Outcomes were captured from patients with pathologic T3a disease with vein involvement. Clinical characteristics were analyzed using SPSS (IBM, Armonk, NY). Local recurrence-free survival (LRFS) and metastasis-free survival (MFS) at 2 years were calculated from Kaplan-Meier survival curves.

RESULTS

For 45 included patients, mean operative and warm ischemia times were 199.6 min ± 47.3 and 30.5 min ± 10.5, with mean estimated blood loss of 324.9 cc ±209.5. Rates of transfusion, embolization, re-admission, and re-operation at 30 days were 8.9% (4/45), 2.2% (1/45), 11.1% (5/45), and 6.7% (3/45; cystoscopic stent placement), respectively. All tumors were malignant on pathology, with clear cell RCC being the most common (91.0%, n=41). The positive margin rate was 6.7% (n=3). Local recurrence occurred in 4.4% (n=2) at a mean time of 5.2 months ± 2.3. Four patients (8.9%) progressed to metastatic disease at a mean of 22.2 months ± 23.0. At 2 years, LRFS was 95.4% and MFS was 95.3%.

CONCLUSIONS

We present the largest known series of patients RPN for pT3a renal masses with venous tumor involvement. We found it both feasible and safe in the appropriate hands. Short term oncologic outcomes for these patients appear more favorable than historic literature suggested. SOURCES OF FUNDING: none.

Does a Positive Surgical Margin After Nephron Sparing Surgery Affect Oncological Outcome in Renal Cell Carcinoma? A Systematic Review and Meta-analysis

We systematically evaluated the impact of positive surgical margins (PSM) on oncological outcomes after partial nephrectomy for renal cell carcinoma. Forty-two studies comprising 101,153 subjects were included and five distinct meta-analyses were performed. PSM was associated with increased risk of local recurrence (hazard ratio (HR) 6.11-high certainty), metastasis (HR 3.29-moderate certainty), overall relapse (HR 2.25-high certainty), overall mortality (HR 1.30-moderate certainty), and may be associated with increased cancer-specific mortality (HR 1.91-low certainty). Patients with PSM should be counseled for the possibility of additional surgery, novel adjuvant therapies, and more rigorous surveillance.

Positive Surgical Margins After Robot-Assisted Partial Nephrectomy Predict Long-Term Oncologic Outcomes for Clinically Localized Renal Masses

Introduction: For patients with clinically localized renal masses, positive surgical margins (PSMs) after robotic partial nephrectomy (RPN) have been associated with a higher risk of disease recurrence, although some studies have challenged this conclusion. Owing to inconsistent reports and a lack of long-term robotic data, the clinical impact of PSM after RPN remains uncertain. We evaluate long-term (>6 years) survival outcomes after RPN in patients with clinically localized disease with respect to surgical margin status. Methods: We conducted a retrospective review of patients who underwent RPN for clinically localized renal masses from June 2007 to December 2012 at Washington University School of Medicine. Disease recurrence and overall survival (OS) were stratified on the presence or absence of PSM. The cohort was analyzed to identify patient- and tumor-specific characteristics associated with PSM. Results: We identified 374 RPNs performed from 2007 to 2012 with a mean follow-up time of 77.7 months (SD 32.2 months). PSM was identified in 12 (3.2%) patients. Patients with PSM were at 14-fold increased risk for recurrence with no difference in OS (p < 0.001, p = 0.130, respectively). Patients with PSM had higher incidence of chronic obstructive pulmonary disease (COPD) (25% vs 6.4%) and greater blood loss (425 mL vs 203 mL). Conclusion: With an extended follow-up period of 77 months after RPN, we found that PSM substantially increased the risk of recurrence without impacting OS. Our finding that PSM may occur more frequently in older patients with COPD must be confirmed in larger studies.

The Nephrologist's Management of Renal Cell Carcinoma After Kidney Surgery

Renal cell carcinoma is associated with chronic kidney disease as well as with common risk factors including hypertension and diabetes mellitus. Localized renal cell carcinoma is treated surgically and in these cases has a favorable prognosis. In particular, in those individuals with small renal masses (≤4 cm), preservation of kidney function should be prioritized. Postoperative chronic kidney disease or end-stage renal disease prevention should include baseline kidney function and risk factor assessment, nontumor renal biopsy, as well as counseling on treatment options to discuss maximizing kidney function preservation. Postnephrectomy prognosis can be determined with repeat laboratory and clinical assessment. Ultimately, early involvement of the nephrologist in a multidisciplinary team including the urology team will enable the reduction of postsurgical kidney disease related morbidity and potentially mortality.

The spinal distribution of metastatic renal cell carcinoma: Support for locoregional rather than arterial hematogenous mode of early bony dissemination

BACKGROUND

Quantifying the degree to which spinal involvement of metastatic renal cell carcinoma (mRCC) is a locoregional phenomenon vs. a hematogenous, bone-specific affinity has implications for prognosis and antimetastatic therapy.

OBJECTIVE

To investigate the distribution of spinal metastasis in mRCC and to explore relationships between clinical factors and patterns of spinal spread.

METHODS

Patients with mRCC and spinal involvement from June 2005 to November 2018 were identified. Clinical and biologic features including primary tumor size and degree of spinal and nonbony metastatic involvement were collected. Spinal distributions were evaluated by the permutation test, with the null hypothesis that metastases are distributed uniformly across levels.

RESULTS

One hundred patients with 685 spinal levels involved by mRCC were evaluated. A nonuniform spatial distribution was observed across the cohort (P < 0.001); a preponderance of thoracolumbar involvement was noted with the mode at L3. No significant deviation in metastatic distribution from uniform was observed in right- or left-sided tumors, subgroups of distant or local metastases, or histology. Patients with smaller tumors (<4 cm) and local spread had distribution of spinal metastases not significantly different from uniform (P = 0.292 and P = 0.126, respectively).

CONCLUSIONS

These data support a dominant locoregional as opposed to arterial hematogenous mechanism for early spinal dissemination of mRCC. Characterizations of the biologic molecular features contributing to osseous tropism and aggressive tumor biology (as seen in the subset of outlier patients with small tumors who appear to have more uniform spread), have implications for surveillance and are an area of active investigation.

Percutaneous thermoablation of small renal masses (T1a) in surgical candidate patients: oncologic outcomes

OBJECTIVE

To evaluate the local tumour progression-free survival (LTPFS), metastasis-free survival (MFS), cancer-specific survival (CSS) and overall survival (OS) of healthy surgical candidates who underwent percutaneous thermoablation (TA) as a first-line therapy for small renal masses (T1a).

METHODS

The institutional review board approved this bi-institutional retrospective study of 85 consecutive surgical candidates with 97 biopsy-proven malignant renal masses (T1a) treated with percutaneous TA from 2008 to 2016. The LTPFS, MFS, CSS and OS rates were calculated using the Kaplan-Meier method. Descriptive analysis was also performed.

RESULTS

The median tumour size was 2.3 cm (range, 0.7-3.9 cm). The minimal and mean follow-up periods were 24 and 56 months, respectively. Local recurrence was detected in four patients (4.7%) at 8.5, 13.8, 58.0 and 64.0 months of follow-up and retreated successfully with percutaneous TA. No patient developed metastatic renal cell carcinoma, and none died due to renal oncologic complications. One patient died of heart attack. The 5-year LTPFS, OS, MFS and CSS rates were 93.0%, 98.4%, 100% and 100%, respectively. Only two patients (2.3%) had major complications (Clavien-Dindo grade > II), including ureteropelvic junction stenosis and urinary obstruction due to ureteral blood clots.

CONCLUSIONS

Our study demonstrates that percutaneous TA is a feasible and effective first-line therapy for healthy surgical candidates with small renal masses (T1a). The 5-year LTPFS, OS, CSS and MFS rates were 93.0%, 98.4%, 100% and 100%, respectively, with a major complication rate of only 2.3%.

KEY POINTS

• Image-guided percutaneous thermoablation of small renal malignancies was effective in 95.3% of the healthy surgical candidates. • Major complications were detected in 2.3% of the patients. • The local tumour progression-free survival rate was 97.6% and 93.0% at 3 and 5 years, respectively.

Cryoablation for Secondary Renal Cell Carcinoma After Surgical Nephrectomy

PURPOSE

To retrospectively evaluate the clinical outcomes of cryoablation for secondary renal cell carcinoma for patients with a history of nephrectomy for initial renal cell carcinoma.

MATERIALS AND METHODS

Thirty patients with 40 renal tumors who had undergone a nephrectomy for initial renal cell carcinoma and cryoablation for renal cell carcinoma as a secondary treatment during the period from April 2014 to December 2018 at a single center institution were enrolled. The patients' overall survival, local control, relapse-free survival, change of renal function, and complications were evaluated. The clinical factors of relapse-free survival were also evaluated.

RESULTS

The 5 year overall survival rate was 94.5%, the 5 year local control rate was 89.3%, and the 5 year relapse-free survival rate (RFSR) was 56.3%. There was an average reduction in renal function of 8.5% after 1 year, and > grade 3 complications occurred in only one case. The RFSR in the patients whose initial stage was T3 was 0%, significantly lower than the 70.4% RFSR in the patients whose initial stage was T1 or T2.

CONCLUSION

Cryoablation for secondary renal cell carcinoma after nephrectomy was safe and provided good local control with preserved renal function. However, the indications for cryoablation should be carefully considered for patients with T3-stage initial renal cell carcinoma, because of the high risk of relapse.

LEVEL OF EVIDENCE

III.

Off-clamp tumor excision using soft coagulation in laparoscopic and robotic partial nephrectomy

INTRODUCTION

The aim of this study was to assess the perioperative outcomes of off-clamp tumor excision using soft coagulation in laparoscopic and robotic partial nephrectomy.

METHODS

We retrospectively analyzed the data from 78 patients who underwent minimally invasive partial nephrectomy, using soft coagulation, at the Shiga University of Medical Science, between September 2013 and April 2017. Tumor excision and hemostasis without renal arterial clamping was performed using soft coagulation. Collecting system repair and renorrhaphy with arterial clamping were carried out only if the collecting system had been opened.

RESULTS

Forty-three of the 78 patients underwent laparoscopic partial nephrectomy using soft coagulation and the other 35 patients underwent robotic partial nephrectomy using soft coagulation. The median estimated total blood loss was 73 (0-1140) mL and no patient needed a blood transfusion. No cases featured postoperative hemorrhagic events. Six patients with urinary fistula needed prolonged ureteral stenting. The median percentage change of the estimated glomerular filtration rate was -7.2 at one to 3 months after surgery.

CONCLUSION

The off-clamp soft coagulation technique in laparoscopic partial nephrectomy and robotic partial nephrectomy is a safe and feasible approach to excise kidney tumors. This procedure may reduce the incidence of perioperative hemorrhagic complications.

Use of hemostatic agents for surgical bleeding in laparoscopic partial nephrectomy: Biomaterials perspective

In recent years, there was an abrupt increase in the incidence of renal tumors, which prompt up the appearance of cutting-edge technology, including minimally invasive and organ-preserving approaches, such as laparoscopic partial nephrectomy (LPN). LPN is an innovative technique used to treat small renal masses that have been gaining popularity in the last few decades due to its promissory results. However, the bleeding control remains the main challenge since the majority of currently available hemostatic agents (HAs) used in other surgical specialities are inefficient in LPN. This hurried the search for effective HAs adapted for LPN surgical peculiarities, which resulted on the emergence of different types of topical HAs. The most promising are the natural origin HAs because of their inherent biodegradability, biocompatibility, and lowest toxicity. These properties turn them top interests' candidates as HAs in LPN. In this review, we present a deep overview on the progress achieved in the design of HAs based on natural origin polymers, highlighting their distinguishable characteristics and providing a clear understanding of their hemostat's role in LPN. This way it may be possible to establish a structure-composition properties relation, so that novel HAs for LPN can be designed to explore current unmet medical needs.

Acute kidney injury after nephrectomy: a new nomogram to predict postoperative renal function

Background

We aimed to develop a nomogram based on preprocedural features for early prediction of acute kidney injury (AKI) and to assess the prognosis in patients after radical and partial nephrectomy.

Methods

The study included a development cohort of 1111 patients who were treated between June 2012 and June 2017 and an additional validation cohort of 356 patients who were treated between July 2017 and June 2018. Stepwise regression and logistic regression analyses were used to evaluate the association between predictors and AKI. Incorporating all independent predictors, a nomogram for postoperative AKI was developed and externally validated. Patients were followed up for 5 years to assess renal function, acute kidney disease (AKD), chronic kidney disease (CKD), hospital readmission and mortality were key prognosis we focused on.

Results

After multivariate logistic regression, radical nephrectomy (odds ratio (OR) = 3.57, p < 0.001), aspirin (OR = 1.79, p = 0.008), systolic blood pressure (OR = 1.41, p = 0.004), triglyceride (OR = 1.26, p = 0.024), and alkaline phosphatase (OR = 1.75, p = 0.034) were independent risk factors for postoperative AKI, while albumin (OR = 0.72, p = 0.031) was a protective factor for postoperative AKI. Patients with a higher estimated glomerular filtration rate (eGFR) (60–90 ml/min/1.73 m², OR = 0.41, p = 0.004; ≥ 90 ml/min/1.73 m², OR = 0.37, p < 0.001) were less prone to AKI than those with a lower eGFR (< 15 ml/min/1.73 m²). These predictors were all included in the final nomogram. The area under the receiver operating characteristics curve for the model were 0.77 (p < 0.001) in the development cohort and 0.72 (p < 0.001) in the validation cohort. The incidence of AKD and CKD were 27.12 and 18.64% in AKI group, which were much higher than those in no AKI group (p < 0.001).

Conclusions

The nomogram had excellent predictive ability and might have significant clinical implications for the early detection of AKI in patients undergoing nephrectomy.

Radiofrequency ablation (RFA) of T1a renal cancer with externally cooled multitined expandable electrodes

INTRODUCTION

To retrospectively evaluate the mid-term outcomes of percutaneous radiofrequency ablation (RFA) with multitined expandable electrodes externally cooled with saline solution in patients with T1a renal cell carcinoma (RCC).

MATERIALS AND METHODS

In this retrospective study, we evaluated 39 RCC in 35 patients treated with CT-guided RFA in 41 procedures (2011-2017). All patients were staged T1a, N0, M0 prior to RFA. Mean tumor size was 24.48 mm. A 4-tined expandable RFA electrode cooled with pump-circulating saline was used. Efficacy was evaluated verifying complete tumor necrosis (no contrast enhancement on imaging) at the end of the procedure and on subsequent controls. Follow-up observation period was 5 years. Minor/major complications, hospitalization days, serum creatinine and GFR pre- and post-RFA (compared using paired t test) and post-operative pain (evaluated with NRS after treatment) were considered as safety indicators. Overall survival was also calculated (Kaplan-Meier method).

RESULTS

Of 35 patients, 30/35 had 1 treatment (primary effectiveness rate 86%), 4/35 had 2 treatments and 1/35 had 3 treatments for residual disease. There were no relapses and no mid-long-term complications; 3 minor (8%) and 1 major (2.7%) complications during perioperative period were reported. Mean before and after RFA serum creatinine rates were, respectively, 1.08 mg/dl and 1.11 mg/dl (p value: 0.4117). NRS median value is 0.8. Hospitalization days median value is [2.8 ± 1.9] days. 91.4% of all patients survived, with a median overall survival time of 65 months.

CONCLUSIONS

Mid-term results show that CT-guided RFA with multitined expandable electrodes externally cooled with saline solution is an effective and safe treatment in patients with RCC-staged T1aN0M0. Data reported in our study are in line with data reported in the literature from patients treated with other devices.

Robust Association between Acute Kidney Injury after Radical Nephrectomy and Long-term Renal Function

The association between acute kidney injury (AKI) and long-term renal function after radical nephrectomy has not been evaluated fully. We reviewed 558 cases of radical nephrectomy. Postoperative AKI was defined by the Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria. Values of estimated glomerular filtration rate (eGFR) were collected up to 36 months (median 35 months) after surgery. The primary outcome was new-onset chronic kidney disease (CKD) stage 3a or higher or all-cause mortality within three years after nephrectomy. The functional change ratio (FCR) of eGFR was defined as the ratio of the most recent GFR (24-36 months after surgery) to the new baseline during 3-12 months. A multivariable Cox proportional hazard regression analysis for new-onset CKD and a multivariable linear regression analysis for FCR were performed to evaluate the association between AKI and long-term renal outcomes. A correlation analysis was performed with the serum creatinine ratio and used to determine AKI and FCR. AKI occurred in 43.2% (n = 241/558) and our primary outcome developed in 40.5% (n = 226/558) of patients. The incidence of new-onset CKD was significantly higher in patients with AKI than those without at all follow-up time points after surgery. The Cox regression analysis showed a graded association between AKI and our primary outcome (AKI stage 1: Hazard ratio 1.71, 95% confidence interval 1.25-2.32; AKI stage 2 or 3: Hazard ratio 2.72, 95% confidence interval 1.78-4.10). The linear regression analysis for FCR showed that AKI was significantly associated with FCR (β = -0.168 ± 0.322, p = 0.011). There was a significant negative correlation between the serum creatinine ratio and FCR. In conclusion, our analysis demonstrated a robust and graded association between AKI after radical nephrectomy and long-term renal functional deterioration.

Comparative Clinicopathologic Characteristics and Outcomes of Paediatric and Adult Xp11 Translocation Renal Cell Carcinomas: a Retrospective Multicentre Study in China

This study aimed to compare the clinicopathologic features and prognosis in patients with Xp11 translocation renal cell carcinomas (RCCs). In total, 8083 RCCs were screened at five centres from January 2007 to December 2018, including 8001 adults (≥18 years) and 82 children (<18 years). Finally, 73 adults and 17 children were identified as Xp11 translocation RCCs, accounting for 1.1% (90 of 8083) of the RCCs. However, 4 children and 1 adult were excluded because of loss to follow-up when performing the survival analysis. The proportion of paediatric and adult Xp11 translocation RCCs was 20.7% (17 of 82) and 0.9% (73 of 8001) of RCCs, respectively, and the incidence in children and adults was significantly different (P < 0.01). Lymph node positivity (LN+) most commonly occurred in children (58.8%) compared with adults (28.8%; P = 0.02), but children with LN+ showed significantly higher five-year overall survival and progression-free rates (OS: 75.0%; PFS: 64.8%) than adult patients (OS: 40.3%; PFS: 0%) (log-rank P^PFS < 0.01; P^OS = 0.04). Multivariable analysis indicated that local lymph node metastasis was associated with both PFS (HR = 0.10; 95% CI 0.02–0.51; P = 0.01) and OS (HR = 0.11; 95% CI 0.01–0.98; P = 0.04) in adults. Adult patients with LN+ may indicate a worse prognosis than paediatric patients.

Scintigraphic evaluation of renoprotective effects of coenzyme Q10 in a rat renal ischemia-reperfusion injury

PURPOSE

Renal ischemia-reperfusion injury (RIRI) may occur secondary to several reasons leading to renal failure. Coenzyme-Q10 (CoQ10) is a well-known antioxidant. However, the effects CoQ10 against RIRI have not been evaluated. Our aim was to evaluate protective effects of CoQ10 to renal ischemia-reperfusion by biochemical, immunohistochemical and scintigraphic findings.

METHODS

Thirty Wistar-albino rats were randomly separated into groups of 10; Group Sham; Group ischemia-reperfusion (IR) had left renal pedicle clamping; Group CoQ10+IR had IR and CoQ10. Twenty-four hours later after reperfusion, scintigraphy was performed and after that, rats were sacrificed. To demonstrate effects of RIRI, serum urea and creatinine levels and tissue levels oxidative stress markers were evaluated. Both kidneys were subjected to histopathological evaluation and to confirm RIRI-induced immunohistochemical aspects of apoptosis, terminal-deoxynucleotidyl-transferase mediated-deoxyuridine-triphosphate-nick-end-labeling assay and caspase-3 were assessed.

RESULTS

Tissue oxidative stress, histopathologic changes, apoptosis scores and quantitative scintigraphic parameters were significantly higher in Group IR compared with Group Sham. Although tissue oxidative stress levels and histopathologic changes were not significant, quantitative scintigraphic parameters of contralateral kidney of Group IR were significantly increased. Compared with Group IR, Group CoQ10+IR presented decreased tissue oxidative stress levels; decreased scores of histopathology and apoptosis; and decreased quantitative scintigraphic parameters with increased split renal function in ischemic kidney.

CONCLUSIONS

Our results suggest that other than its antioxidant properties, CoQ10 shows antiperoxidative, antiapoptotic and antiinflammatory potential in protecting renal functioning of ischemic kidney. Furthermore, our results show that renal scintigraphy is a feasible method to detect early changes in renal functioning after RIRI.

Prediction of significant estimated glomerular filtration rate decline after renal unit removal to aid in the clinical choice between radical and partial nephrectomy in patients with a renal mass and normal renal function

OBJECTIVES

To develop a clinically applicable predictive model to quantitate the risk of estimated glomerular filtration rate (eGFR) decline to ≤45 mL/min/1.73 m2 after radical nephrectomy (RN) to better inform decisions between RN and partial nephrectomy (PN).

PATIENTS AND METHODS

Our prospectively maintained kidney cancer registry was reviewed for patients with a preoperative eGFR >60 mL/min/1.73 m2 who underwent RN for a localized renal mass. New baseline renal function was indexed. We used multivariable logistic regression to develop a predictive nomogram and evaluated it using receiver-operating characteristic (ROC) analysis. Decision-curve analysis was used to assess the net clinical benefit.

RESULTS

A total of 668 patients met the inclusion criteria, of whom 183 (27%) experienced a decline in eGFR to ≤45 mL/min/1.73 m2 . On multivariable analysis, increasing age (P = 0.001), female gender (P < 0.001), and increasing preoperative creatinine level (P < 0.001) were associated with functional decline. We constructed a predictive nomogram that included these variables in addition to comorbidities with a known association with kidney disease, but found that a simplified model excluding comorbidities was equally robust (cross-validated area under the ROC curve was 0.78). Decision-curve analysis showed the net clinical benefit at probabilities >~11%.

CONCLUSIONS

The decision to perform RN vs PN is multifaceted. We have provided a simple quantitative tool to help identify patients at risk of a postoperative eGFR of ≤45 mL/min/1.73 m2 , who may be stronger candidates for nephron preservation.

Effect of 3-Dimensional Virtual Reality Models for Surgical Planning of Robotic-Assisted Partial Nephrectomy on Surgical Outcomes: A Randomized Clinical Trial

IMPORTANCE

Planning complex operations such as robotic-assisted partial nephrectomy requires surgeons to review 2-dimensional computed tomography or magnetic resonance images to understand 3-dimensional (3-D), patient-specific anatomy.

OBJECTIVE

To determine surgical outcomes for robotic-assisted partial nephrectomy when surgeons reviewed 3-D virtual reality (VR) models during operative planning.

DESIGN, SETTING, AND PARTICIPANTS

A single-blind randomized clinical trial was performed. Ninety-two patients undergoing robotic-assisted partial nephrectomy performed by 1 of 11 surgeons at 6 large teaching hospitals were prospectively enrolled and randomized. Enrollment and data collection occurred from October 2017 through December 2018, and data analysis was performed from December 2018 through March 2019.

INTERVENTIONS

Patients were assigned to either a control group undergoing usual preoperative planning with computed tomography and/or magnetic resonance imaging only or an intervention group where imaging was supplemented with a 3-D VR model. This model was viewed on the surgeon's smartphone in regular 3-D format and in VR using a VR headset.

MAIN OUTCOMES AND MEASURES

The primary outcome measure was operative time. It was hypothesized that the operations performed using the 3-D VR models would have shorter operative time than those performed without the models. Secondary outcomes included clamp time, estimated blood loss, and length of hospital stay.

RESULTS

Ninety-two patients (58 men [63%]) with a mean (SD) age of 60.9 (11.6) years were analyzed. The analysis included 48 patients randomized to the control group and 44 randomized to the intervention group. When controlling for case complexity and other covariates, patients whose surgical planning involved 3-D VR models showed differences in operative time (odds ratio [OR], 1.00; 95% CI, 0.37-2.70; estimated OR, 2.47), estimated blood loss (OR, 1.98; 95% CI, 1.04-3.78; estimated OR, 4.56), clamp time (OR, 1.60; 95% CI, 0.79-3.23; estimated OR, 11.22), and length of hospital stay (OR, 2.86; 95% CI, 1.59-5.14; estimated OR, 5.43). Estimated ORs were calculated using the parameter estimates from the generalized estimating equation model. Referent group values for each covariate and the corresponding nephrometry score were summed across the covariates and nephrometry score, and the sum was exponentiated to obtain the OR. A mean of the estimated OR weighted by sample size for each nephrometry score strata was then calculated.

CONCLUSIONS AND RELEVANCE

This large, randomized clinical trial demonstrated that patients whose surgical planning involved 3-D VR models had reduced operative time, estimated blood loss, clamp time, and length of hospital stay.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers (1 registration per site): NCT03334344, NCT03421418, NCT03534206, NCT03542565, NCT03556943, and NCT03666104.

Changing trends in surgical management of renal tumours from 2000 to 2016: a nationwide study of Medicare claims data

BACKGROUND

Guidelines recommend nephron sparing surgery where possible for patients with T1 renal tumours. The trends of nephron sparing surgery outside the USA are limited, particularly since the introduction of robotic-assisted partial nephrectomy (RAPN). The aim of this study was to describe contemporary surgical management patterns of renal tumours in Australia according to Medicare claims data.

METHODS

Claims data according to the Medicare Benefits Schedule on surgical management of renal tumours in adult Australians between January 2000 and December 2016 was collated. Analysis of absolute number, population-adjusted rate and renal cancer-adjusted rate of interventions according to age and gender were performed, as well as proportion of RAPN.

RESULTS

Between 2000 and 2016, the rate of partial nephrectomy (PN) increased while radical nephrectomy (RN) remained stable (PN: 0.87-4.16, RN: 6.52-6.70 per 100 000 population). Since 2015, PN has become more common than RN in patients aged 25 to 44 years (0.98 versus 0.95 procedures per 100 000 population). Renal cancer-adjusted rate exhibited a trend towards increasing utilization of PN and reduced RN across all age groups. An increase in overall surgical treatment was observed (25%-41%), mainly due to increased treatment of patients older than 75 years. The proportion of RAPN was seen to rapidly increase (4.7% in 2010 to 58% in 2016).

CONCLUSIONS

Treatment utilization for renal masses has markedly changed in Australia according to Medicare claims. PN is increasingly replacing RN in younger patients, and older patients are receiving more surgical treatment. The impact of increased RAPN utilization is yet to be determined.

Low level of Cyclin-D1 correlates with worse prognosis of clear cell renal cell carcinoma patients

Cyclin-D1 (CCND1) belongs to the highly conserved cyclin family whose members are characterized by abundant expression during the cell cycle. As an oncogene, high level of CCND1 was observed and related to poor prognosis and tumor recurrence in many cancers. In this study, we focused on the role of CCND1 in the clinical outcome of clear cell renal cell carcinoma (ccRCC). Gene Expression Omnibus database, The Cancer Genome Atlas database, and immunohistochemical staining were used. The mRNA and protein levels of CCND1 were significantly enhanced in ccRCC tumor tissues. However, the low level of CCND1, but not high level of CCND1, was related to poor prognosis and tumor recurrence in ccRCC. Further analysis showed that CCND1 mRNA level decreased with increasing ccRCC tumor grades and the rate of recurrence in ccRCC patients. In a nomogram model, the CCND1 mRNA level was shown to help predict ccRCC patient recurrence. CCND1 is a strong determinant for prediction of recurrence. The patients with high CCND1 level appear to have a more favorable prognosis together with more frequent low-grade tumors and low rate of recurrence. This is the first study to investigate the prognostic roles of CCND1 in ccRCC and discovered that CCND1 had an unconventional positive impact on the clinical outcome of ccRCC patients.

Case report of a combined oncocytoma and type 1 papillary renal cell carcinoma: a rare entity

An extremely rare renal hybrid tumor composed of papillary renal cell carcinoma (PRCC) and renal oncocytoma (RO) within the same tumor is described. Only eight previous cases are documented in the literature. A 44-year-old man showed a 3.5 cm renal mass composed by areas with tubulo-papillary structures made up with small cells with scanty cytoplasm adjacent to polygonal cells forming solid sheet and tubules with abundant eosinophilic cytoplasm and uniform, round central nuclei without mitoses. Complete immunohistochemical panel suggested a diagnosis of type 1 PRCC combined with RO. Contrary to previous cases of hybrid renal tumors reported in the literature, no pseudocapsule divided the two histotypes of tumors. Our patient is the youngest among the previous reports being 44. Collision tumours have previously been described, although mixed renal tumours composed of oncocytoma and PRCC is extremely rare. There is no evidence to suggest a relationship between oncocytoma and papillary RCC since they originate from different cells and have different prognoses. Given the possibility of oncocytomas to harbour other tumours, we suggest careful examination of the samples to exclude the presence of an associated malignant neoplasm, which might have a significantly worse prognosis than oncocytoma. Differential diagnosis is needed, and immunohistochemical stains are of great help in distinguishing between the two histological components.

Fluorescence-guided selective arterial clamping during RAPN provides better early functional outcomes based on renal scan compared to standard clamping

To compare the functional and operative outcomes of robot-assisted partial nephrectomy with selective arterial clamping guided by near infrared fluorescence imaging (NIRF-RAPN) versus a cohort of patients who underwent standard RAPN without selective arterial clamping (S-RAPN). 62 consecutive patients underwent RAPN from January 2016 to May 2017: the last 20 patients underwent NIRF-RAPN. Preoperative and postoperative renal scan at 1 month were performed to evaluate the glomerular filtration rate (GFR) of the operated renal unit and total function. Functional and operative outcomes of cases were compared with a cohort of 42 patients undergoing S-RAPN. Selective clamping was performed in 15 patients (75%), whereas five (25%) cases were converted to S-RAPN, due to incomplete ischemic appearance of the tumor after selective clamping. Median tumor diameter was 40 mm in both groups. Median selective clamping was 24 min in both groups. Operative time (206' vs 190') and blood loss (200 vs 170 cc) were comparable. No major complications have been reported in the NIRF-RAPN group, whereas three acute hemorrhages with embolization were found in the S-RAPN group. The analysis of renal scan data revealed that a greater loss of GFR in the operated renal unit was observed after S-RAPN compared to NIRF-RAPN [21.5% vs. 5.5%; p = 0.046], as well as total GFR loss [8% vs 0%; p = 0.007]. The use of NIRF imaging was associated with improved short-term renal functional outcomes compared to RAPN without selective arterial clamping. To our knowledge, this is the first comparative study analyzing the GFR obtained from renal scan.

Percutaneous cryoablation for renal cell carcinoma using ultrasound-guided targeting and computed tomography-guided ice-ball monitoring: radiation dose and short-term outcomes

BACKGROUND

Usefulness of ultrasound (US)-guided mass targeting and computed tomography (CT)-guided ice-ball monitoring in percutaneous cryoablation (PCA) for renal cell carcinoma (RCC) is still uncertain.

PURPOSE

To assess radiation dose and short-term outcomes of PCA for RCC using US-guided targeting and CT-guided ice-ball monitoring.

MATERIAL AND METHODS

Thirty-nine consecutive patients who underwent PCA for biopsy-proven RCC were included. Mass targeting was performed with US and ice-ball was monitored with CT guidance. Effective radiation dose of CT during PCA was recorded. Follow-up was conducted with contrast-enhanced CT or magnetic resonance imaging (MRI) (mean follow-up time = 10.1 ± 7.0 months). Local tumor progression was defined by the presence of focal enhancing areas at the ablation zone (CT, ≥ 20 HU; MRI, presence of focal enhancement on subtraction contrast-enhanced image). Technical success, major complication rate (e.g. Clavien-Dindo classification ≥ 3), and one-year local tumor progression-free survival (PFS) rate were analyzed.

RESULTS

Mean effective radiation dose in association with PCA was 12.1 ± 4.5 mSv (range = 7.0-25.2 mSv). Technical success was achieved in 100%. Local tumor progression occurred in a single patient (2.6%, 1/39), and one-year local tumor PFS rate was 95.7%. No major complication was found.

CONCLUSION

PCA using US-guided targeting and CT-guided ice-ball monitoring may allow acceptable local tumor control for RCC, as a radiation-reducing strategy.

Evaluation of a Chitosan Hemostat in a Porcine Laparoscopic Partial Nephrectomy Model: A Pilot Study

Background and Objective: The ideal hemostatic agent for laparoscopic partial nephrectomy (LPN) would provide complete hemostasis and sealing of the collecting system at a low cost. Chitosan (CS) is an established topical hemostatic agent, but standard sterilization techniques affect its functional and biologic properties, thereby preventing parenteral uses. This study sought to characterize the safety and efficacy of an implanted CS hemostat sterilized with either a standard technique, electron beam (e-beam) irradiation, or a novel technique, nonthermal nitrogen plasma, in a porcine LPN model. Methods: Laparoscopic partial nephrectomies were performed on six farm pigs and hemostasis achieved using only a CS hemostatic agent (Clo-Sur P.A.D.) that was e-beam (n = 3) or plasma sterilized (PS) (n = 3). Number of pads needed to achieve hemostasis, estimated blood loss, operative time, mass of kidney resection, and warm ischemia time were measured. Animals were monitored for 14 weeks and at harvest, retrograde ureteropyelography and histologic analysis were performed. Results: Complete hemostasis and collection system sealing were achieved in both groups. There was a trend toward less pads required for hemostasis (p = 0.056) and reduced blood loss (p = 0.096) with PS pads, although this did not achieve statistical significance. No complications were observed for 14 weeks and gross examination showed the implanted CS was encapsulated in a fibrous capsule. Histologic analysis revealed a healed nephrectomy site with residual CS and associated chronic inflammation, reactive fibrosis, and foreign body giant cell formation. Importantly, the adjacent renal tissue was intact and viable with no residual parenchymal inflammation or cytologic damage. Conclusion: CS pads alone provided safe and effective hemostasis in a porcine LPN model. PS may enhance hemostatic efficacy and resorption compared with e-beam.

Diagnostic value of imprint cytology testing in kidney tumors: review of 200 cases

INTRODUCTION

Previous investigations have studied the importance of imprint cytology (IC) testing of core needle biopsy (CNB) from various organs. We have presented the largest series, to the best of our knowledge, of IC testing of CNB for patients with kidney tumors.

MATERIALS AND METHODS

The present retrospective study (January 1, 2015, through January 30, 2016) identified laboratory information through a computer search of the cytology archived reports for 200 consecutive IC testing with CNB for renal tumors cases. A board-certified cytopathologist and cytology-trained fellow reviewed the IC testing and CNB slides and rendered them as nondiagnostic, positive for malignancy, negative for malignancy, positive for neoplasm, or atypical. The tumors were graded using the International Society of Urological Pathology grading system. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

The IC testing cases classified as atypical (n = 53) or positive for neoplasm (n = 28) were evaluated separately because of the ambiguous morphologic characteristics. Of the other 119 cases, IC testing classified 95 (80%) as positive for malignancy, 5 (4%) as negative for malignancy, and 19 (16%) as nondiagnostic. The corresponding CNB histologic diagnoses showed that 85 of 95 cases (89%) were true positive for malignancy. Of these 85 cases, 45 (53%) were low grade, 21 (25%) were high grade, and 19 (22%) were ungraded. The corresponding sensitivity, specificity, and accuracy were 85%, 11%, and 58%, respectively. The 53 IC-identified atypical cases were more likely to be malignant (n = 40; 75%). Of the remaining IC testing atypical cases, 12 (23%) were negative for malignancy and 1 (2%) was nondiagnostic. Of the 28 cases positive for neoplasm using IC, 13 (46%) were positive and 15 (54%) were negative for malignancy.

CONCLUSIONS

The relatively low diagnostic value of IC testing for renal tumors showed it to be less powerful for screening than its use in other organs.

"At-risk" kidney: How surgical factors influence renal functional preservation after partial nephrectomy

OBJECTIVES

To investigate the influence of surgical modifiable factors on chronic kidney disease upstaging in a contemporary cohort of patients with normal and "at-risk" kidneys undergoing partial nephrectomy.

METHODS

We reviewed 778 consecutive patients with (n = 634)/without (n = 144) chronic kidney disease or risk factors for chronic kidney disease in our institutional partial nephrectomy database. Chronic kidney disease upstaging was assessed using glomerular filtration rate measurements preoperatively and at 3-12 months postoperatively. Using a multivariate logistic regression, baseline clinicodemographic factors, and the operative measurements of excisional volume loss and warm and cold ischemia time on rates of chronic kidney disease upstaging were determined. Marginal effects were used to analyze the impact of ischemia time and generate interaction curves.

RESULTS

Chronic kidney disease/risk factors for chronic kidney disease had equivalent rates of chronic kidney disease upstaging as the healthy kidney cohort (31.5% vs 38.2%, P = 0.15). Of the entire cohort, 2.8% were upstaged to stage IV-V chronic kidney disease. Multivariate analysis found a significant association between chronic kidney disease upstaging and excisional volume loss in both cohorts (no chronic kidney disease/risk factors for chronic kidney disease: odds ratio 1.63, P = 0.04; chronic kidney disease/risk factors for chronic kidney disease: odds ratio 1.42, P = 0.001). Only in the chronic kidney disease/risk factors for chronic kidney disease cohort, there was an association between ischemia type/duration and chronic kidney disease upstaging (odds ratio 1.04, P = 0.04). Warm ischemia began to predict an increased risk of chronic kidney disease upstaging at 17.6 min, which became statistically significant at 49 min.

CONCLUSIONS

Chronic kidney disease upstaging is common after partial nephrectomy. Although volume loss unequivocally affects rates of upstaging irrespective of baseline renal function, warm ischemia time disproportionately influences "at-risk" kidneys. Therefore, strong consideration should be given to minimizing volume loss and using cold ischemia when extended clamp times are anticipated in "at-risk" kidneys.

Surveillance versus ablation for incidentally diagnosed small renal tumours: the SURAB feasibility RCT

BACKGROUND

There is uncertainty around the appropriate management of small renal tumours. Treatments include partial nephrectomy, ablation and active surveillance.

OBJECTIVES

To explore the feasibility of a randomised trial of ablation versus active surveillance.

DESIGN

Two-stage feasibility study: stage 1 - clinician survey and co-design work; and stage 2 - randomised feasibility study with qualitative and economic components.

METHODS

Stage 1 - survey of radiologists and urologists, and development of patient information materials. Stage 2 - patients identified across eight UK centres with small renal tumours (< 4 cm) were randomised (1 : 1 ratio) to ablation or active surveillance in an unblinded manner. Randomisation was carried out by a central computer system. The primary objective was to determine willingness to participate and to randomise a target of 60 patients. The qualitative and economic data were collected separately.

RESULTS

The trial was conducted across eight centres, with a site-specific period of recruitment ranging from 3 to 11 months. Of the 154 patients screened, 36 were eligible and were provided with study details. Seven agreed to be randomised and one patient was found ineligible following biopsy results. Six patients (17% of those eligible) were randomised: three patients received ablation and no serious adverse events were recorded. The 3- and 6-month data were collected for four (67%) and three (50%) out of the six patients, respectively. The qualitative substudy identified factors directly impacting on the recruitment of this trial. These included patient and clinician preferences, organisational factors (variation in clinical pathway) and standard treatment not included. The health economic questionnaire was designed and piloted; however, the sample size of recruited patients was insufficient to draw a conclusion on the feasibility of the health economics.

CONCLUSIONS

The trial did not meet the criteria for progression and the recruitment rate was lower than hypothesised, demonstrating that a full trial is presently not possible. The qualitative study identified factors that led to variation in recruitment across the sites. Implementation of organisational and operational measures can increase recruitment in any future trial. There was insufficient information to conduct a full economic analysis.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN31161700.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 81. See the NIHR Journals Library website for further project information.

Germline genetic variants in somatically significantly mutated genes in tumors are associated with renal cell carcinoma risk and outcome

Genome-wide association studies (GWAS) have identified 13 susceptibility loci for renal cell carcinoma (RCC). Additional genetic loci of risk remain to be explored. Moreover, the role of germline genetic variants in predicting RCC recurrence and overall survival (OS) is less understood. In this study, we focused on 127 significantly mutated genes from The Cancer Genome Atlas (TCGA) Pan-Cancer Analysis across 12 major cancer sites to identify potential genetic variants predictive of RCC risk and clinical outcomes. In a three-phase design with a total of 2657 RCC cases and 5315 healthy controls, two single nucleotide polymorphisms (SNPs) that map to PIK3CG (rs6466135:A, ORmeta = 0.85, 95% CI = 0.77-0.94, Pmeta = 1.4 × 10-3) and ATM (rs611646:T, ORmeta = 1.17, 95% CI = 1.05-1.31, Pmeta = 3.5 × 10-3) were significantly associated with RCC risk. With respect to RCC recurrence and OS, two separate datasets with a total of 661 stages I-III RCC patients (discovery: 367; validation: 294) were analyzed. The most significant association was observed for rs10932384:C (ERBB4) with both outcomes (recurrence: HRmeta = 0.52, 95% CI = 0.39-0.68, Pmeta = 3.81 × 10-6; OS: HRmeta = 0.50, 95% CI = 0.37-0.67, Pmeta = 6.00 × 10-6). In addition, six SNPs were significantly associated with either RCC recurrence or OS but not both (Pmeta < 0.01). Rs10932384:C was significantly correlated with mutation frequency of ERBB4 in clear cell RCC (ccRCC) patients (P = 0.003, Fisher's exact test). Cis-eQTL was observed for several SNPs in blood/transformed fibroblasts but not in RCC tumor tissues. In summary, we identified promising genetic predictors of recurrence and OS among RCC patients with localized disease.

The Use of 3-Dimensional, Virtual Reality Models for Surgical Planning of Robotic Partial Nephrectomy

OBJECTIVE

To determine whether 3-dimensional virtual reality models of patient-specific anatomy improve outcomes in patients undergoing robotic partial nephrectomy.

MATERIALS AND METHODS

Computed tomography and magnetic resonance imaging scans for 30 patients undergoing robotic partial nephrectomy were converted to 3-dimensional virtual reality models prior to the patient's operation. These models were then viewed on the surgeon's mobile phone pre- and intraoperatively using a Google Cardboard headset to assist in surgical planning. This group was compared to 30 patients who previously underwent robotic partial nephrectomy. We compared operative time, clamp time, estimated blood loss, hospital stay, complications, and margin status between these groups. We used forward selecting multivariate regression models to create the final model controlling for significant demographic and clinical variables.

RESULTS

When controlling for case complexity and surgeon, patients with 3-dimensional, virtual reality-assisted surgical planning had significantly lower operative time (141 minutes vs 201 minutes, P < .0001), clamp time (13.2 minutes vs 17.4 minutes, P = .0274), and estimated blood loss (134 cc vs 259 cc, P = .0233). Patients without 3-dimensional, virtual reality-assisted surgical planning were more likely to have a hospital stay of greater than 2 days (odds ratio 5.1, 95% confidence interval 1.0, 26.4). There were no complications or positive margins noted in the VR group.

CONCLUSION

Use of a 3-dimensional, virtual reality model when performing robotic partial nephrectomy improves key surgical outcome parameters.

Oncologic outcomes of nephron-sparing surgery in patients with T1 multifocal renal cell carcinoma

OBJECTIVE

This study is performed to explore the pathological characteristics and oncologic outcomes of T1 multifocal renal cell carcinoma (RCC).

METHODS

The clinical data of 600 patients (442 males and 158 females) between the age of 29 and 73 years, diagnosed with T1 RCC were collected from three hospitals in China, out of which 421 cases had undergone nephron-sparing surgery (NSS) and 179 cases had undergone radical nephrectomy (RN) between December 2010 and January 2015.

RESULTS

Tumor was identified with multifocality in 32 patients (5.33%), out of which 21 were set to receive NSS, and 11 to receive RN, respectively; 21 cases of clear cell tumor, 8 cases of papillary tumor, 1 case of chromophobe tumor and 2 cases of Xp.11.2 translocation RCC. Among 568 cases of monofocal tumors, 400 patients underwent NSS, and the remaining 168 patients underwent RN, respectively. After a median follow-up of 5 years, 13 patients were found with recurrent tumors out of those who had undergone NSS, 11 with monofocal tumors and 2 with multifocal tumors containing satellite tumor nodules (p = 0.13). Out of the 32 individuals with multifocal RCC, 4 cases were reported to have died of cancer, 2 of NSS and 2 of RN. From these findings, the cancer-specific survival for NSS and RN was estimated to be 90.48% and 81.82%, respectively (p = 0.48).

CONCLUSION

The findings from the study suggested that there were pathological differences in multifocal renal tumors, and that papillary carcinoma may be more common than clear cell carcinoma. The recurrence rate and survival rate of multifocal RCC were similar to monofocal tumors. Tumor recurrence may be related to satellite tumor nodules, which can only be detected once surgery is performed.

Ischemia Techniques in Nephron-sparing Surgery: A Systematic Review and Meta-Analysis of Surgical, Oncological, and Functional Outcomes

CONTEXT

The optimal ischemia technique at partial nephrectomy (PN) for renal masses is yet to be determined.

OBJECTIVE

To summarize and analyze the current evidence about surgical, oncological, and functional outcomes after different ischemia techniques (cold, warm, and zero ischemia) at PN.

EVIDENCE ACQUISITION

A computerized systematic literature search was performed by using PubMed (MEDLINE) and Science Direct. Identification and selection of the studies were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria. Outcomes of interest were estimated blood loss (EBL), overall complications, positive surgical margins, local tumor recurrence, and renal function preservation. Meta-analysis and forest-plot diagrams were performed. Overall pooled estimates, together with 95% confidence intervals (CIs), of the incidence of all parameters were obtained using a random effect model (RE-Model) on the log transformed means (MLN), proportion, or standardized mean change, as deemed appropriate.

EVIDENCE SYNTHESIS

One hundred and fifty-six studies were included. No clinically meaningful differences were found in terms of EBL after cold (mean: 215.5; 95% CI: 154.2-276.8m), warm (mean: 201.8; 95% CI: 175.0-228.7ml), or zero (mean: 261.2; 95% CI: 171.0-351.3ml) ischemia technique. Overall, postoperative complications were recorded in 14.1% (95% CI: 6.7-27.4), 11.1% (95% CI: 10.0-12.3), and 9.7% (95% CI: 7.7-12.2) of patients after cold, warm, and zero ischemia (p<0.01), respectively. Positive surgical margins were recorded in 4.8% (95% CI: 1.9-10.9), 4.0% (95% CI: 3.4-4.8), and 5.6% (95% CI: 3.1-9.8) of patients after cold, warm, and zero ischemia (p<0.01), respectively. Local recurrence was recorded in 3.2% (95% CI: 1.9-5.2) and 3.1% (95% CI: 0.7-11.5) of patients after warm and zero ischemia (p<0.01), respectively. The log₂ of estimated glomerular filtration ratio mean changes were-1.37 (95% CI:-3.42 to 0.68),-1.00 (-2.04 to 0.03), and-0.71 (-1.15 to-0.27) ml/min after cold, warm, and zero ischemia, respectively. Low level of evidence, retrospective nature of most of included studies, a high risk of selection bias, and heterogeneity within included studies limited the overall quality of the analysis.

CONCLUSIONS

The effect of ischemia technique at PN is still debatable and subject to confounding by several factors, namely, patients' selection criteria, surgical technique used, and percentage of functional parenchyma spared during surgery. These confounders bias available evidence and were addressed by only a small part of available studies. Unfortunately, the overall quality of literature evidences and the high risk of selection bias limit the possibility of any causal interpretation about the relationship between the ischemia technique used and surgical, oncological, or functional outcomes. Thus, none of the available ischemia technique could be recommended over the other.

PATIENT SUMMARY

The present analysis shows that none of the available ischemia techniques, namely, cold, warm, or zero ischemia, is universally superior to the others, and other factors play a role in the surgical outcome.