A Systematic Review of Research Gaps in the Evaluation and Management of Localized Renal Masses

Renal and major clinical outcomes and their determinants after nephrectomy in patients with pre-existing chronic kidney disease: A retrospective cohort study

The consequences of partial nephrectomy (PN) compared to radical nephrectomy (RN) are less documented in patients with pre-existing chronic kidney disease (CKD) or with solitary kidney (SK). We assessed renal outcomes, and their determinants, after PN or RN in a retrospective cohort of patients with moderate-to-severe CKD (RN-CKD and PN-CKD) or SK (PN-SK). All surgical procedures conducted between 2013 and 2018 in our institution in patients with pre-operative estimated glomerular filtration rate (eGFR)<60 mL/min/1.73m2 or with SK were included. The primary outcome was a composite criterion including CKD progression or major adverse cardio-vascular events (MACE) or death, assessed one year after surgery. Predictors of the primary outcome were determined using multivariate analyses. A total of 173 procedures were included (67 RN, and 106 PN including 27 SK patients). Patients undergoing RN were older, with larger tumors. Preoperative eGFR was not significantly different between the groups. One year after surgery, PN-CKD was associated with lower rate of the primary outcome compared to RN-CKD (43% vs 71% p = 0.007). In multivariate analysis, independent risk factors for the primary outcome were postoperative AKI (stage 1 to stage 3 ranging from OR = 8.68, 95% CI 3.23-23.33, to OR = 28.87, 95% CI 4.77-167.61), larger tumor size (OR = 1.21 per cm, 95% CI 1.02-1.45), while preoperative eGFR, age, sex, diabetes mellitus, and hypertension were not. Postoperative AKI after PN or RN was the major independent determinant of worse outcomes (CKD progression, MACE, or death) one year after surgery.

Long-Term Follow-Up in Patients Undergoing Renal Mass Biopsy: Seeding is not Anecdotal

INTRODUCTION

Renal biopsy is recommended if the outcome might alter therapeutic decisions for patients who present with renal masses of unclear etiology. However, little is known about long-term risks related to this procedure.

PATIENTS AND METHODS

We performed a retrospective analysis of an institutional database maintained by a tertiary referral center that included patients who underwent renal biopsies between 2003 and 2005 with a follow-up of at least 15 years. Renal biopsies were taken percutaneously with a coaxial technique according to guideline recommendations and included off-line ultrasound guidance.

RESULTS

We identified 106 patients who underwent biopsies for a renal mass of unclear etiology. The median age was 58.7 years (43.7-66.2). A median of 4.2 (3-6) biopsies were collected from each patient. Tumor seeding leading to local growth was identified in 6 patients (5,7%) after a median follow-up of 8.2 years. Four of these lesions that were resected exhibited the same histology as the original biopsy result; these patients experienced no further recurrence. In 45 patients (42%), the biopsy results led to a therapy other than surgery (n = 28 lymphoma, n = 6 metastasis from other malignancies, n = 11 oncocytoma). The remaining 61 patients (58%) were diagnosed with renal cell carcinoma treated either surgically or with ablation. None of the patients developed metastatic spread related to tumor seeding.

CONCLUSION

Tumor seeding after renal mass biopsy is a rare, but relevant risk associated with this procedure. As indications for renal mass biopsy increase, longer-term follow-up and improved biopsy techniques should be considered to address this complication.

Decision-making in active surveillance in kidney cancer: current trends and future urine and tissue markers

Surveillance for small renal masses is a growing choice of management amongst physicians and patients. These decisions, however, can be difficult as patient factors and tumor factors may blur the line between continued surveillance and intervention. Currently, there are no biomarkers that are readily available to aid in the decision making for patients with known renal cell carcinoma; however, many show promise. We herein review the literature of the adjunct tools that are currently available for decision making in small renal masses, but also new potential biomarkers that can potentially be of use.

Oncological outcomes of active surveillance and percutaneous cryoablation of small renal masses are similar at intermediate term follow-up

BACKGROUND

Active surveillance (AS) and minimally invasive ablative therapies such as percutaneous cryoablation (PCA) are emerging as alternative treatment modalities in the management of small renal masses (SRMs).

METHODS

Fifty-nine patients underwent PCA since 2011 and 75 underwent AS since 2010 at two different institutions. Only patients with follow-up ≥ 6 months were included. All patients were followed with a standardized protocol. Treatment failure was defined by dimensional progression for AS and renal recurrence for PCA, in addition to stage and/or metastatic progression for both groups.

RESULTS

Treatment failure was observed in 14 cases (18,7%) during AS (mainly due to dimensional progression) and 12 patients (16%) underwent delayed intervention with a mean follow-up of 36,83 months. Seven patients (11,9%) in the PCA group experienced treatment failure with a mean follow-up of 33,39 months and 3 of them underwent re-ablation successfully. Cancer-specific-survival at 2 and 5 years was 100% and 95,8% in AS-group vs. 98,2% and 98,2% in PCA-group (p=0,831). One patient in both groups died from metastatic disease. Overall-survival at 2 and 5 years was 91,7% and 82,4% in the AS-group vs. 96,5% and 96,5% in the PCA-group (p=0,113). Failure-free survival at 2 and 5 years was 90,9% and 70,1% in the AS-group vs. 93,1% and 70,9% in the PCA-group (p=0,645).

CONCLUSIONS

AS and PCA provide similar survival outcomes and are safe and valid treatment options for elderly and comorbid patients with SRMs.

The future of perioperative therapy in advanced renal cell carcinoma: how can we PROSPER?

Patients with high-risk renal cell carcinoma (RCC) experience high rates of recurrence despite definitive surgical resection. Recent trials of adjuvant tyrosine kinase inhibitor therapy have provided conflicting efficacy results at the cost of significant adverse events. PD-1 blockade via monoclonal antibodies has emerged as an effective disease-modifying treatment for metastatic RCC. There is emerging data across other solid tumors of the potential efficacy of neoadjuvant PD-1 blockade, and preclinical evidence supporting a neoadjuvant over adjuvant approach. PROSPER RCC is a Phase III, randomized trial evaluating whether perioperative nivolumab increases recurrence-free survival in patients with high-risk RCC undergoing nephrectomy. The neoadjuvant component, intended to prime the immune system for enhanced efficacy, distinguishes PROSPER from other purely adjuvant studies and permits highly clinically relevant translational studies.

Essential Research Priorities in Renal Cancer: A Modified Delphi Consensus Statement

BACKGROUND

Identification of clear and focused research priorities is crucial to drive research forward.

OBJECTIVE

To identify research priorities in renal cell carcinoma (RCC) through a multidisciplinary collaboration between clinicians, researchers, and patients.

DESIGN, SETTING, AND PARTICIPANTS

In phase I, 44 RCC experts provided 24 literature reviews within their field, summarising research gaps (RGs). Three expert discussion meetings and patient interviews were performed, and 39 potential RGs were identified. In phase II, experts (N=82) scored these gaps on a nine-point scale (1-3: not important; 4-6: important; 7-9: critical) through a multistep Delphi process involving three online surveys and two further consensus meetings. The surveys aimed to reach a consensus, defined as ≥70% agreement by experts.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Three iterations of the Delphi survey were performed. The results obtained after the third Delphi survey were distributed amongst the RCC experts and patient representatives for final feedback.

RESULTS AND LIMITATIONS

In the first Delphi survey, the response rate was 56% (46/82), increasing to 67% (55/82) and 71% (58/82) in the second and third iterations, respectively. Survey respondents included 45.7% urologists, 37.0% oncologists, 8.7% radiologists, and 8.6% other specialists (pathologists, health economists, geneticist, and scientists). The process resulted in the identification of 14 crucial RGs, across a broad range of RCC themes. Key themes included further research into systemic therapies for RCC and management strategies that maximise quality of life, especially in patient groups that are "difficult to treat" and have rarer RCC subtypes. Two crucial RGs relate to biomarkers and novel imaging approaches for both localised and metastatic disease, to enable prognostic risk stratification and individualise patient management. Study participants were from a UK and European setting; therefore, we acknowledge that the RGs identified represent European priorities.

CONCLUSIONS

These RGs will facilitate international collaboration towards a concerted attempt to improve patients' survival and quality of life.

PATIENT SUMMARY

We formed a collaboration between researchers, clinicians, and patients to identify research priorities in kidney cancer. We identified 14 priorities that will improve patient outcomes by focusing on research efforts.

A scoping review describes methods used to identify, prioritize and display gaps in health research

BACKGROUND AND OBJECTIVES

Different methods to examine research gaps have been described, but there are still no standard methods for identifying, prioritizing, or reporting research gaps. This study aimed to describe the methods used to identify, prioritize, and display gaps in health research.

METHODS

A scoping review using the Arksey and O'Malley methodological framework was carried out. We included all study types describing or reporting on methods to identify, prioritize, and display gaps or priorities in health research. Data synthesis is both quantitative and qualitative.

RESULTS

Among 1,938 identified documents, 139 articles were selected for analysis; 90 (65%) aimed to identify gaps, 23 (17%) aimed to determine research priorities, and 26 (19%) had both aims. The most frequent methods in the review were aimed at gap identification and involved secondary research, which included knowledge synthesis (80/116 articles, 69%), specifically systematic reviews and scoping reviews (58/80, 73%). Among 49 studies aimed at research prioritization, the most frequent methods were both primary and secondary research, accounting for 24 (49%) reports. Finally, 52 (37%) articles described methods for displaying gaps and/or priorities in health research.

CONCLUSION

This study provides a mapping of different methods used to identify, prioritize, and display gaps or priorities in health research.

Comparative effectiveness of management options for patients with small renal masses: a prospective cohort study

OBJECTIVES

To explore the comparative effectiveness of partial nephrectomy (PN), radical nephrectomy (RN), ablative therapies (ablation) and active surveillance (AS) for small renal masses (SRMs; tumour diameter ≤4.0 cm) in the domains of survival, renal function and quality of life (QoL) using the prospectively maintained Delayed Intervention and Surveillance for Small Renal Masses (DISSRM) Registry.

PATIENTS AND METHODS

Estimated glomerular filtration rate (eGFR) was calculated from creatinine values to determine renal function. QoL was measured using the Short Form 12 (SF-12) questionnaire. The Kaplan-Meier method and Cox proportional hazards regression were used for survival analysis. The mixed-effects model was used for renal function and QoL analysis.

RESULTS

Of 638 patients, 231 (36.2%) chose PN, 41 (6.4%) RN, 27 (4.2%) ablation and 339 (53.1%) AS. Cancer-specific survival at 7 years was 98.8% in PN patients and 100% in all other groups. Overall survival (OS) at 7 years was 87.9%, 90.2%, 83.5% and 66.1% in PN, RN, ablation and AS patients, respectively. The OS rate was significantly worse in the AS group than other groups and likely attributable to older age and increased comorbidities. The eGFR was lowest in RN patients but comparable in all other groups. QoL was lowest in AS patients due to lower physical health scores, but mental health scores were similar in all groups.

CONCLUSIONS

With excellent oncological outcomes in all groups, nephron-sparing approaches, like PN and ablation, are preferred over RN when intervention is indicated for SRMs. AS is a reasonable option for select patients, given the comparable oncological and mental health outcomes.

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.

Quantitative computer-aided diagnostic algorithm for automated detection of peak lesion attenuation in differentiating clear cell from papillary and chromophobe renal cell carcinoma, oncocytoma, and fat-poor angiomyolipoma on multiphasic multidetector computed tomography

OBJECTIVE

To evaluate the performance of a novel, quantitative computer-aided diagnostic (CAD) algorithm on four-phase multidetector computed tomography (MDCT) to detect peak lesion attenuation to enable differentiation of clear cell renal cell carcinoma (ccRCC) from chromophobe RCC (chRCC), papillary RCC (pRCC), oncocytoma, and fat-poor angiomyolipoma (fp-AML).

MATERIALS AND METHODS

We queried our clinical databases to obtain a cohort of histologically proven renal masses with preoperative MDCT with four phases [unenhanced (U), corticomedullary (CM), nephrographic (NP), and excretory (E)]. A whole lesion 3D contour was obtained in all four phases. The CAD algorithm determined a region of interest (ROI) of peak lesion attenuation within the 3D lesion contour. For comparison, a manual ROI was separately placed in the most enhancing portion of the lesion by visual inspection for a reference standard, and in uninvolved renal cortex. Relative lesion attenuation for both CAD and manual methods was obtained by normalizing the CAD peak lesion attenuation ROI (and the reference standard manually placed ROI) to uninvolved renal cortex with the formula [(peak lesion attenuation ROI - cortex ROI)/cortex ROI] × 100%. ROC analysis and area under the curve (AUC) were used to assess diagnostic performance. Bland-Altman analysis was used to compare peak ROI between CAD and manual method.

RESULTS

The study cohort comprised 200 patients with 200 unique renal masses: 106 (53%) ccRCC, 32 (16%) oncocytomas, 18 (9%) chRCCs, 34 (17%) pRCCs, and 10 (5%) fp-AMLs. In the CM phase, CAD-derived ROI enabled characterization of ccRCC from chRCC, pRCC, oncocytoma, and fp-AML with AUCs of 0.850 (95% CI 0.732-0.968), 0.959 (95% CI 0.930-0.989), 0.792 (95% CI 0.716-0.869), and 0.825 (95% CI 0.703-0.948), respectively. On Bland-Altman analysis, there was excellent agreement of CAD and manual methods with mean differences between 14 and 26 HU in each phase.

CONCLUSION

A novel, quantitative CAD algorithm enabled robust peak HU lesion detection and discrimination of ccRCC from other renal lesions with similar performance compared to the manual method.