Survival in Patients With Primary Metastatic Renal Cell Carcinoma Treated With Sunitinib With or Without Previous Cytoreductive Nephrectomy: Results From a Population-based Registry

Real-World Impact of Upfront Cytoreductive Nephrectomy in Metastatic Non-Clear Cell Renal Cell Carcinoma Treated with First-Line Immunotherapy Combinations or Tyrosine Kinase Inhibitors (A Sub-Analysis from the ARON-1 Retrospective Study)

BACKGROUND

About 20% of patients with renal cell carcinoma present with non-clear cell histology (nccRCC), encompassing various histological types. While surgery remains pivotal for localized-stage nccRCC, the role of cytoreductive nephrectomy (CN) in metastatic nccRCC is contentious. Limited data exist on the role of CN in metastatic nccRCC under current standard of care.

OBJECTIVE

This retrospective study focused on the impact of upfront CN on metastatic nccRCC outcomes with first-line immune checkpoint inhibitor (IO) combinations or tyrosine kinase inhibitor (TKI) monotherapy.

METHODS

The study included 221 patients with nccRCC and synchronous metastatic disease, treated with IO combinations or TKI monotherapy in the first line. Baseline clinical characteristics, systemic therapy, and treatment outcomes were analyzed. The primary objective was to assess clinical outcomes, including progression-free survival (PFS) and overall survival (OS). Statistical analysis involved the Fisher exact test, Pearson's correlation coefficient, analysis of variance, Kaplan-Meier method, log-rank test, and univariate/multivariate Cox proportional hazard regression models.

RESULTS

Median OS for patients undergoing upfront CN was 36.8 (95% confidence interval [CI] 24.9-71.3) versus 20.8 (95% CI 12.6-24.8) months for those without CN (p = 0.005). Upfront CN was significantly associated with OS in the multivariate Cox regression analysis (hazard ratio 0.47 [95% CI 0.31-0.72], p < 0.001). In patients without CN, the median OS and PFS was 24.5 (95% CI 18.1-40.5) and 13.0 months (95% CI 6.6-23.5) for patients treated with IO+TKI versus 7.5 (95% CI 4.3-22.4) and 4.9 months (95% CI 3.0-8.1) for those receiving the IO+IO combination (p = 0.059 and p = 0.032, respectively).

CONCLUSIONS

Our study demonstrates the survival benefits of upfront CN compared with systemic therapy without CN. The study suggests that the use of IO+TKI combination or, eventually, TKI monotherapy might be a better choice than IO+IO combination for patients who are not candidates for CN regardless of IO eligibility. Prospective trials are needed to validate these findings and refine the role of CN in current mRCC management.

Understanding and integrating cytoreductive nephrectomy with immune checkpoint inhibitors in the management of metastatic RCC

Cytoreductive nephrectomy became accepted as standard of care for selected patients with metastatic renal cell carcinoma (mRCC) because of improved survival observed in patients treated with cytoreductive nephrectomy in combination with interferon-α in two randomized clinical trials published in 2001. Over the past two decades, novel systemic therapies have shown higher treatment response rates and improved survival outcomes compared with interferon-α. During this rapid evolution of mRCC treatments, systemic therapies have been the primary focus of clinical trials. Results from multiple retrospective studies continue to suggest an overall survival benefit for selected patients treated with nephrectomy in combination with systemic mRCC treatments, with the notable exception of one debated clinical trial. The optimal timing for surgery is unknown, and proper patient selection remains crucial to improving surgical outcomes. As systemic therapies continue to evolve, clinicians have an increasing need to understand how to incorporate cytoreductive nephrectomy into the management of mRCC.

The role of cytoreductive nephrectomy in metastatic renal cell carcinoma in the targeted therapy and immunological therapy era: a systematic review and meta-analysis

BACKGROUND

The role of cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC) remains controversial. In addition, several unanswered questions regarding the use of CN remain: Can CN provide survival benefits for patients with mRCC? Where do we place CN in the treatment sequence paradigm among patients with mRCC? How do we best stratify patients with mRCC for CN therapy?

MATERIALS AND METHODS

A search strategy was conducted in the PubMed, Embase, and Web of Science databases. Studies were included only in the English language. The risk of bias assessment was made by using ROBINS-I (Risk of Bias in Nonrandomized Studies of Interventions) and RoB 2 (Risk of Bias 2) tools. The expected outcomes were analyzed by meta-analyses with the fixed-effects model or random effects model, including overall survival (OS) and progression-free survival (PFS). The measure of effect was the hazard ratio (HR) with a 95% CI, and sensitivity analysis was conducted to assess the reliability of the final results.

RESULTS

A total of 30 studies were included in the qualitative analysis. The HR for OS was 0.55 (95% CI, 0.50-0.61), and PFS was 0.72 (95% CI, 0.66-0.80), favoring CN compared with no CN. The upfront CN plus targeted therapy (TT) group had superior OS (HR, 0.57; 95% CI, 0.51-0.64) compared with the TT alone group. Furthermore, upfront CN plus systemic therapy (ST) was associated with numerically inferior OS compared with ST plus deferred CN in patients with mRCC (HR, 1.31; 95% CI, 0.98-1.74). Finally, the leave-one-out test of sensitivity analysis indicated that the results of this meta-analysis were stable and reliable in the overall HR estimates for these survival outcomes.

CONCLUSIONS

First, CN was associated with better survival than no CN in patients with mRCC. Second, the combination of upfront CN and TT may lead to superior survival outcomes compared to TT alone in patients with mRCC. Survival outcomes were similar between the upfront CN+ST group and the ST+deferred CN group in patients with mRCC. Exact patient selection based on baseline prognostic factors is needed to promise maximal survival for patients with mRCC.

Cytoreductive nephrectomy for synchronous metastatic renal cell carcinoma. Is there enough evidence?

OBJECTIVE

To assess the role of Cytoreductive Nephrectomy for synchronous metastatic Renal Cell Carcinoma patients in the Systemic Therapy era and beyond regarding the Overall Survival, the optimal sequence between Systemic Therapy and Cytoreductive Nephrectomy and prognostic factors.

METHODS

The systematic review was conducted in accordance with the PRISMA guidelines. Bibliographic search was performed in Medline (PubMed), ClinicalTrials.gov, and Cochrane Library-Cochrane Central Register of Controlled Trials (CENTRAL). Studies included were those indexed from 2005 in an attempt to limit those conducted in the cytokine era. Risk of bias assessment was performed by two authors (K.S and T.L) using the Cochrane Collaborative Risk of Bias tool for randomized trials, the Cochrane Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for nonrandomized studies.

RESULTS

Cytoreductive nephrectomy was associated with improved overall survival in all but one of the observational studies. While in all of these studies the unvariable analysis showed improved overall survival in favor of the cytoreductive nephrectomy group in some studies the subgroup analysis showed no benefit. Regarding the optimal sequence, deferred cytoreductive nephrectomy demonstrated better results in more studies than upfront cytoreductive nephrectomy but a advantage was not clearly certain. In the analysis of possible prognostic factors for overall survival with cytoreductive nephrectomy, most common prognostic factors found were age (in 8 studies), tumor histology (in 7 studies), number of metastasis (in 6 studies), and T stage.

CONCLUSIONS

Cytoreductive nephrectomy can still play an important role in wisely selected patients, although the role of cytoreductive nephrectomy in the new immunotherapy era needs to be defined.

Do Metastatic Kidney Cancer Patients Benefit From Cytoreductive Nephrectomy? A Real-World Retrospective Study From the SEER Database

Introduction: The benefit of cytoreductive nephrectomy (CN) for metastatic kidney cancer has been challenged recently. The study aimed to evaluate the prognostic roles of surgical resection of primary tumor site for metastatic kidney cancer under a real-world setting.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database (2010–2015) and the overall survival (OS) and cancer-specific survival (CSS) were evaluated using the Cox proportional hazards regression model. One-to-one matching using the propensity score was used to estimate and compare the survival rates.

Results: The SEER data contain records of 8,932 patients from 2010 to 2015. The data showed that 61.7% of the patients underwent CN while 38.2% did not receive any surgery. The median survival month for a patient without surgery was 4 months and for a patient with surgery was 19 months. The multivariate analysis showed that surgical resection of the primary tumor site was an independent favorable predictor for both OS and CSS (all p < 0.001) in the original and the matching cohort.

Conclusions: In the era of target therapy, CN might still be a vital method to treat metastatic kidney cancer.

Nephrectomy improves the survival of metastatic renal cell cancer patients with moderate to good performance status-results from a Finnish nation-wide population-based study from 2005 to 2010

Background

The purpose of this study was to evaluate the effects of cytoreductive nephrectomy (CN) and metastasectomies on the survival of patients with synchronous metastatic renal cell cancer (mRCC) using real-life, population-based national dataset.

Methods

Nationwide data, including all cases of synchronous mRCC in Finland diagnosed on a 6-year timeframe, based on the Finnish Cancer Registry and complemented with patient records from the treating hospitals, were analyzed. Patients with Eastern Cooperative Oncology Group (ECOG) performance status 3–4 were excluded. Univariate and adjusted multivariable survival analysis were performed, including subgroup analysis for patients with different medical therapies. Nephrectomy complications were also analyzed.

Results

A total of 732 patients were included in the analysis. CN was performed for 389 (53.1%) patients, whereas 68 (9.3%) patients underwent nephrectomy and metastasectomies of all lesions (surgery with curative intent). Median overall survival (OS) for patients who did not undergo nephrectomy was 5.9 (95% confidence interval [CI] = 4.6–7.2) months. Patients who had a CN had a median OS of 16.6 (95% CI = 14.2–19.1, p < 0.001) months, whereas patients who had surgery with curative intent had a median OS of 51.3 (95% CI = 36.0–66.6, p < 0.001) months. The survival benefit of CN and metastasectomies remained significant in all medical therapy subgroups and in both of the applied multivariable statistical models.

Conclusions

Surgical treatment of metastatic renal cell cancer is associated with a significant survival benefit in patients with good and moderate performance status, regardless of the chosen medical therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02308-0.

Development and validation of a nomogram to predict overall survival for patients with metastatic renal cell carcinoma

Background

Heterogeneity of metastatic renal cell carcinoma (RCC) constraints accurate prognosis prediction of the tumor. We therefore aimed at developing a novel nomogram for accurate prediction of overall survival (OS) of patients with metastatic RCC.

Methods

We extracted 2010 to 2016 data for metastatic RCC patients in the Surveillance, Epidemiology, and End Results (SEER) database, and randomly stratified them equally into training and validation sets. Prognostic factors for OS were analyzed using Cox regression models, and thereafter integrated into a 1, 3 and 5-year OS predictive nomogram. The nomogram was validated using the training and validation sets. The performance of this model was evaluated by the Harrell’s concordance index (C-index), calibration curve, integrated discrimination improvement (IDI), category-free net reclassification improvement (NRI), index of prediction accuracy (IPA), and decision curve analysis (DCA).

Results

Overall, 2315 metastatic RCC patients in the SEER database who fulfilled our inclusion criteria were utilized in constructing a nomogram for predicting OS of newly diagnosed metastatic RCC patients. The nomogram incorporated eight clinical factors: Fuhrman grade, lymph node status, sarcomatoid feature, cancer-directed surgery and bone, brain, liver, and lung metastases, all significantly associated with OS. The model was superior to the American Joint Committee on Cancer (AJCC) staging system (7th edition) both in training (C-indices, 0.701 vs. 0.612, P < 0.001) and validation sets (C-indices, 0.676 vs. 0.600, P < 0.001). The calibration plots of the nomogram corresponded well between predicted and observed values. NRI, IDI, and IPA further validated the superior predictive capability of the nomogram relative to the AJCC staging system. The DCA plots revealed reliable clinical application of our model in prognosis prediction of metastatic RCC patients.

Conclusions

We developed and validated an accurate nomogram for individual OS prediction of metastatic RCC patients. This nomogram can be applied in design of clinical trials, patient counseling, and rationalizing therapeutic modalities.

Cytoreductive Nephrectomy in Patients Presenting With Advanced Disease: Have We Finally Answered the Question?

Determining the appropriate patients for cytoreductive nephrectomy (CN) has evolved with the integration of more effective systemic therapies for patients with metastatic renal cell carcinoma (mRCC). While previously considered to be first-line therapy for mRCC, CN has not demonstrated a significant survival advantage over systemic therapy in more recent randomized trials when compared with targeted therapy. Conversely, multiple observational studies demonstrate a therapeutic benefit for CN. This review synthesizes the current literature regarding patient selection for CN and further evaluates the role of CN in the current era of immune checkpoint inhibitor therapy. With careful patient selection, CN maintains an important role in the management of mRCC patients.

Contemporary Cytoreductive Nephrectomy Provides Survival Benefit in Clear-cell Metastatic Renal Cell Carcinoma

INTRODUCTION

A recent randomized trial questioned the role of cytoreductive nephrectomy in clear-cell metastatic renal cell carcinoma (ccmRCC). We reassessed the effect of cytoreductive nephrectomy on survival in a contemporary population-based ccmRCC cohort.

PATIENTS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2010-2015), we focused on patients with ccmRCC. The primary endpoint consisted of overall mortality. Univariable and multivariable Cox regression models were applied in the overall cohort and in patients who underwent targeted therapy. Sensitivity analyses included 1:1 propensity score matching, 3- and 6-month landmark analyses, incremental survival benefit analyses, and metastases number and location-based stratifications.

RESULTS

Of 4062 patients with ccmRCC, 2241 (55.1%) received targeted therapy; cytoreductive nephrectomy was performed in 2226 (54.8%) patients and 1168 (52.1%) patients in the overall and targeted therapy cohorts, respectively. Cytoreductive nephrectomy was associated with lower overall mortality in the overall cohort (median survival, 30 vs. 9 months; hazard ratio [HR], 0.43; P < .001), as well as in the targeted therapy cohort (median survival, 28 vs. 12 months; HR, 0.49; P < .001). In sensitivity analyses, cytoreductive nephrectomy was associated with lower overall mortality after 1:1 propensity score-matching (HR, 0.49; P < .001), in 3- and 6-month landmark analyses (HR, 0.49; P < .001 and HR, 0.51; P < .001, respectively), in metastases number and location-based stratifications, except for exclusive liver metastases, as well as in all incremental benefit analyses.

CONCLUSION

Cytoreductive nephrectomy is associated with better survival in patients with ccmRCC, including those exposed to targeted therapy, after adjustment for multiple potential confounders.

Cytoreductive Nephrectomy in the Era of Tyrosine Kinase and Immuno-Oncology Checkpoint Inhibitors

The role for cytoreductive nephrectomy (CN) in the treatment of metastatic renal cell carcinoma (mRCC) has evolved with advancements in systemic therapy. During the cytokine-based immunotherapy era, CN provided a clear survival benefit and was considered standard of care in management of mRCC. The development of targeted systemic therapy directed at the vascular endothelial growth factor pathway altered the treatment paradigm and accentuated the importance of risk stratification in treatment selection. This article reviews the literature evaluating the benefit of CN during the evolution of systemic therapy and provides clinical recommendations for current utilization of CN in patients with mRCC.

Clinical use of vascular endothelial growth factor receptor inhibitors for the treatment of renal cell carcinoma

In recent years, there have been increased incidences of metastatic renal cell carcinoma (RCC), which is refractory to conventional chemotherapy. Owing to the insensitivity to traditional therapy, targeted therapy becomes a possible alternative strategy. Over the past decade, the development of targeted treatments for metastatic RCC has advanced considerably. Several studies have shown that the vascular endothelial growth factor pathway is an important mediator for the occurrence and development of RCC, and tyrosine kinase inhibitors (TKIs) that target vascular endothelial growth factor receptors (VEGFRs) have been considered optimal therapeutic options for RCC. Six small molecules that inhibit VEGFR1/2/3, namely, sunitinib, sorafenib, axitinib, pazopanib, cabozantinib, and lenvatinib, have been approved by the Food and Drug Administration (FDA) for the treatment of RCC. Additionally, clinical trials assessing seven TKIs that target VEGFRs are currently in progress. To some extent, these drugs improve quality of life and prolong the survival of patients. This paper presents a review of the systemic targeted therapies against VEGFRs that have been approved so far or are undergoing trials as treatments for RCC.

The Current and Evolving Landscape of First-Line Treatments for Advanced Renal Cell Carcinoma

Agents targeting the vascular endothelial growth factor (VEGF) and its receptors (VEGFRs), as well as the mammalian target of rapamycin (mTOR) and immune checkpoint receptor programmed death 1 (PD-1) signaling pathway have improved clinical outcomes for patients with advanced renal cell carcinoma (RCC). The VEGFR tyrosine kinase inhibitors (TKIs) pazopanib and sunitinib are FDA-approved first-line treatment options for advanced RCC; however, other treatment options in this setting are available, including the recently approved combination of nivolumab (anti-PD-1) and ipilimumab (anti-cytotoxic T-lymphocyte-associated protein-4 [CTLA-4]) for patients with intermediate or poor risk. Unfortunately, treatment guideline recommendations provide little guidance to aid first-line treatment choice. In addition, several ongoing randomized phase III trials of investigational first-line regimens may complicate the RCC treatment paradigm if these agents gain approval. This article reviews clinical trial and real-world evidence for currently approved and investigational first-line treatment regimens for advanced RCC and provides clinical evidence to aid first-line treatment selection. IMPLICATIONS FOR PRACTICE: Vascular endothelial growth factor receptor tyrosine kinase inhibitors are approved by the U.S. Food and Drug Administration as first-line treatment options for advanced renal cell carcinoma; however, the treatment paradigm is rapidly evolving. The combination of nivolumab plus ipilimumab was recently approved for intermediate- and poor-risk patients, and other combination strategies and novel first-line agents will likely be introduced soon.

Position of cytoreductive nephrectomy in the setting of metastatic renal cell carcinoma patients: does the CARMENA trial lead to a paradigm shift?

Introduction > The role of cytoreductive nephrectomy (CN) in combination with targeted therapy has been debated after the results of the CARMENA trial. We decided to reassess the available evidence on the setting of CN in metastatic renal cell carcinoma (mRCC) patients. Methods > Critical review of the literature focusing on CN in mRCC patients. Results > Previous trials demonstrated a survival benefit of CN during the cytokine-era. In the targeted therapies-era, retrospective studies has confirmed the survival benefit of CN but presented inherent selection biases. Recently, the CARMENA trial showed that sunitinib alone was not inferior to CN plus sunitinib, and could be followed by subsequent CN in good-responders patients. CN is found to be a morbid surgery (perioperative mortality rate of 0-13% and major postoperative complications rate of 3-36%) and should be avoided in patients with primary refractory disease, using targeted therapy as a selection tool. Some parameters have been associated with shorter overall survival, leading to propose up-front CN only to patients with good performance status, a high-volume renal tumor and a low metastatic burden. Conclusions > While previous studies demonstrated a survival benefit of CN, the CARMENA trial showed that immediate CN was not necessary in some patients with mRCC, leading to a paradigm shift. Targeted therapy should be proposed as first line treatment, and the response to pre-surgical therapy could be used as a selection tool for subsequent decision of CN in good-responders patients.

Efficacy and safety of third- and fourth-line targeted therapy in Japanese patients with metastatic renal cell carcinoma: A retrospective analysis

Introduction:

There is limited data on the efficacy of sequential targeted therapy for metastatic renal cell carcinoma (mRCC) beyond the second line, especially for Asian patients. We evaluated the efficacy and side effects of targeted therapy beyond the second line.

Materials and Methods:

We retrospectively reviewed 69 patients who were administered targeted therapy for mRCC at our institution between 2008 and 2016. Sunitinib, pazopanib, sorafenib, axitinib, everolimus, and temsirolimus were available in Japan in 2016, and treatment had been conducted with those six agents. Twenty-four patients underwent therapy beyond the second line. The progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. In addition, a survey on patients’ attitudes toward cancer treatment was conducted. Twenty-five of the 69 patients responded to the question with their opinions on the continuation of treatment after standard therapy failure.

Results:

The median PFS was 7.6 and 2.5 months for third- and fourth-line therapy. The median OS calculated from the initiation of third-line therapy was 14.2 months. The rates of serious toxicities with third- and fourth-line regimens were not markedly increased compared with first- and second-line therapies. Forty percent of patients hoped to continue treatment after exhausting standard care.

Conclusions:

Our retrospective study indicates the efficacy and safety of third- and fourth-line targeted therapies. In addition to the efficacy, a patient can also influence treatment continuation.

High competing risks minimize real-world utility of adjuvant targeted therapy in renal cell carcinoma: a population-based analysis

Objective

To utilize a population-based approach to address the role of adjuvant TT in the management of RCC.

Methods

Patients with RCC (2006-2013) in the SEER database were stratified by metastatic disease at the time of diagnosis (cM0/cM1). cM0 patients following surgical excision were stratified into low and high-risk (ASSURE and S-TRAC criteria). Multivariable analyses performed to identify predictors of TT receipt; Fine and Gray competing risks analyses used to identify predictors of cancer-specific mortality (CSM). Subset analyses included patients with clear cell histology and high-risk cM0. Survival analyses were used to evaluate overall survival (OS) and cancer-specific survival (CSS) for all cohorts, stratified on TT receipt.

Results

79,926 patients included (71,682 cM0, 8,244 cM1); median follow-up for the entire cohort was 40.1 months. Of 31,453 patients with histologic grade data, 18,328 and 13,125 were low- and high-risk cM0, respectively. TT utilization in cM1 patients peaked at 50.6% and was associated with reduced CSM (HR 0.73, p<0.01). In contrast, TT utilization (presumed salvage therapy) never exceeded 2.2% in the entire cM0 cohort and 3.5% in the high-risk cM0 cohort. On competing risks analysis, TT receipt was associated with increased CSM in all cohorts.

Conclusion

When compared to the cM1 patients, TT receipt in cM0 patients does not provide any cancer-specific survival benefit, even in the small percentage of patients that eventually progress to metastatic disease. Competing risks mortality further limit any potential benefit in this population. Based on current evidence, adjuvant TT cannot be recommended for RCC patients.

Prognostic effect of cytoreductive nephrectomy in synchronous metastatic renal cell carcinoma: a comparative study using inverse probability of treatment weighting

PURPOSE

To test the hypothesis that cytoreductive nephrectomy (CN) improves overall survival (OS) of patients with synchronous metastatic renal cell carcinoma (mRCC), who subsequently receive targeted therapies (TT).

METHODS

We identified 261 patients who received TT for synchronous mRCC with or without prior CN. To achieve balance in baseline characteristics between groups, we used the inverse probability of treatment weighting (IPTW) method. We conducted OS analyses, including IPTW-adjusted Kaplan-Meier curves, Cox regression models, interaction term, and landmark and sensitivity analyses.

RESULTS

Of the 261 patients, 97 (37.2%) received CN and 164 (62.8%) did not. IPTW-adjusted analyses showed a statistically significant OS benefit for patients treated with CN (HR 0.63, 95% CI 0.46-0.83, P = 0.0015). While there was no statistically significant difference in OS at 3 months (P = 0.97), 6 months (P = 0.67), and 12 months (P = 0.11) from diagnosis, a benefit for the CN group was noted at 18 months (P = 0.005) and 24 months (P = 0.004). On interaction term analyses, the beneficial effect of CN increased with better performance status (P = 0.06), in women (P = 0.03), and in patients with thrombocytosis (P = 0.01).

CONCLUSIONS

IPTW-adjusted analysis of our patient cohort suggests that CN improves OS of patients with synchronous mRCC treated with TT. On the whole, the survival difference appears after 12 months. Specific subgroups may particularly benefit from CN, and these subgroups warrant further investigation in prospective trials.

Cytoreductive nephrectomy in patients with metastatic renal cell carcinoma in the era of targeted therapy: a bibliographic review

PURPOSE

To evaluate the role of cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC), against a background of lack of evidence following the introduction of targeted therapy.

METHODS

A literature review was performed in January 2017 using the MEDLINE/PubMed and EMBASE databases. The PRISMA guidelines were followed for conduct of the study. Two authors independently screened the 270 papers retrieved from the search, and the finally selected publications were identified by consensus between the two reviewers. A total of 55 studies were included in the present review.

RESULTS

Globally, the indications for CN have decreased over recent years. Although current guidelines consider CN an adequate option in selected patients based on prospective studies in the cytokine era, evidence for CN in the era of targeted therapy is based on retrospective studies only.

CONCLUSIONS

The results of ongoing prospective studies are still awaited. Retrospective data suggest that young male patients with oligometastatic disease and a good performance status can be considered suitable surgical candidates who may benefit from CN.

Propensity score analysis with partially observed covariates: How should multiple imputation be used?

Inverse probability of treatment weighting is a popular propensity score-based approach to estimate marginal treatment effects in observational studies at risk of confounding bias. A major issue when estimating the propensity score is the presence of partially observed covariates. Multiple imputation is a natural approach to handle missing data on covariates: covariates are imputed and a propensity score analysis is performed in each imputed dataset to estimate the treatment effect. The treatment effect estimates from each imputed dataset are then combined to obtain an overall estimate. We call this method MIte. However, an alternative approach has been proposed, in which the propensity scores are combined across the imputed datasets (MIps). Therefore, there are remaining uncertainties about how to implement multiple imputation for propensity score analysis: (a) should we apply Rubin's rules to the inverse probability of treatment weighting treatment effect estimates or to the propensity score estimates themselves? (b) does the outcome have to be included in the imputation model? (c) how should we estimate the variance of the inverse probability of treatment weighting estimator after multiple imputation? We studied the consistency and balancing properties of the MIte and MIps estimators and performed a simulation study to empirically assess their performance for the analysis of a binary outcome. We also compared the performance of these methods to complete case analysis and the missingness pattern approach, which uses a different propensity score model for each pattern of missingness, and a third multiple imputation approach in which the propensity score parameters are combined rather than the propensity scores themselves (MIpar). Under a missing at random mechanism, complete case and missingness pattern analyses were biased in most cases for estimating the marginal treatment effect, whereas multiple imputation approaches were approximately unbiased as long as the outcome was included in the imputation model. Only MIte was unbiased in all the studied scenarios and Rubin's rules provided good variance estimates for MIte. The propensity score estimated in the MIte approach showed good balancing properties. In conclusion, when using multiple imputation in the inverse probability of treatment weighting context, MIte with the outcome included in the imputation model is the preferred approach.

Description of the EuroTARGET cohort: A European collaborative project on TArgeted therapy in renal cell cancer-GEnetic- and tumor-related biomarkers for response and toxicity

OBJECTIVE

For patients with metastatic renal cell cancer (mRCC), treatment choice is mainly based on clinical parameters. With many treatments available and the limited response to treatment and associated toxicities, there is much interest in identifying better biomarkers for personalized treatment. EuroTARGET aims to identify and characterize host- and tumor-related biomarkers for prediction of response to tyrosine kinase inhibitor therapy in mRCC. Here, we describe the EuroTARGET mRCC patient cohort.

METHODS AND MATERIALS

EuroTARGET is a European collaborative project designed as an observational study for which patients with mRCC were recruited prospectively in 62 centers. In addition, 462 patients with mRCC from previous studies were included. Detailed clinical information (baseline and follow-up) from all patients was entered in web-based case record forms. Blood was collected for germline DNA and pharmacokinetic/pharmacodynamic analyses and, where available, fresh-frozen tumor material was collected to perform tumor DNA, RNA, kinome, and methylome analyses.

RESULTS

In total, 1,210 patients with mRCC were included. Of these, 920 received a tyrosine kinase inhibitor as first-line targeted treatment (sunitinib [N = 713, 78%], sorafenib [N = 41, 4%], or pazopanib [N = 166, 18%]) and had at least 6 months of outcome assessment (median follow-up 15.3 months [interquartile range: 8.5-30.2 months]). Germline DNA samples were available from 824 of these patients, fresh-frozen tumor material from 142 patients, fresh-frozen normal kidney tissue from 95 patients, and tissue microarrays created from formalin-fixed paraffin-embedded tumor material from 247 patients. Of the 920 patients, germline DNA variant chip data were successfully generated for 811 patients (Illumina HumanOmniExpress BeadChip). For 80 patients, next-generation exome sequencing of germline and tumor DNA was performed, tumor RNA sequencing was performed for 124 patients, kinome activity measured and processed for 121 patients (PamChip), and methylome data (Illumina Infinium HumanMethylation450 BeadChip) were created for 116 RCC tissues (and 23 normal kidney tissues). For 73 out of the 920 patients, all platform data types were generated. In addition, 40 patients were included in a pharmacokinetic/pharmacodynamic phase IV substudy.

CONCLUSIONS

Analysis of EuroTARGET cohort data will contribute to personalization of therapy for patients with mRCC. The extensive clinical data and multiplatform EuroTARGET data will be freely available.

[Should cytoreductive nephrectomy be performed in patients with metastatic renal cell carcinoma and what is the scientific rationale?]

Between 15 and 20% of patients diagnosed with renal cell carcinoma suffer from metastatic disease by the time of diagnosis. In the immunotherapy era, the standard treatment was to perform cytoreductive nephrectomy (CN) followed by treatment with interferon α. This was based on two prospective randomized trials and their combined analysis. Since the introduction of targeted therapy, the use of CN came into question and the number of performed CN has declined. Two trials (CARMENA and SURTIME) evaluating the role of CN in the times of targeted therapy have either closed early or are recruiting slowly and will probably not be able to answer this question. Thus, we need to focus on retrospective data consisting of several analyses with large numbers of patients. These analyses all seem to show a benefit in overall survival, and adjusted for prognostic factors CN represents an independent predictor of longer survival. A correlation between expected life span and efficacy of CN has been shown with a survival rate that is three times higher after 3 years. Only patients with low performance status, low life expectancy, cerebral metastases, and old age did not benefit from CN. Furthermore, symptom control of large primary tumors without response to systemic therapy and the fact that all reports of long-term remission or long survival rates are associated with the use of CN are theoretical aspects speaking in favor of this treatment. This leads to the recommendation to perform CN in all patients with good performance status in all important guidelines.

Prognostic significance of platelet-lymphocyte ratio in patients receiving first-line tyrosine kinase inhibitors for metastatic renal cell cancer

BACKGROUND

The platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR) have been reported as prognostic factors in various cancers, but their roles in metastatic renal cell cancer (mRCC) remain unclear. We investigated the significance of PLR and NLR, along with that of established prognostic factors, in mRCC patients receiving first-line tyrosine kinase inhibitors (TKI).

METHODS

Data obtained from 63 mRCC patients who received first-line TKI between 2007 and 2013 were evaluated retrospectively. The association of PLR, NLR, and established prognostic factors with progression-free survival (PFS) and overall survival (OS) was analyzed using the Kaplan-Meier method. The influence of independent prognostic factors on survival was determined using multivariable Cox regression analysis.

RESULTS

High NLR (>3.6) and PLR (>150) were related to shorter PFS (p = 0.001) and OS (p = 0.001). The presence of brain metastases [hazard ratio (HR) 4.94, 95% CI 1.75-13.9; p = 0.002] and high PLR (>150, HR 13.1, 95% CI 5.14-33.2; p = 0.001) were independently associated with PFS, and Eastern Cooperative Oncology Group Performance status ≥2 (HR 3.60, 95% CI 1.39-9.31; p = 0.008), lymph node metastasis (HR 2.76, 95% CI 1.11-6.86; p = 0.029), brain metastasis (HR 9.39, 95% CI 2.74-32.1; p = 0.001), and high PLR (>150, HR 16.1, 95% CI 4.41-58.4; p = 0.001) with OS.

CONCLUSIONS

High PLR was associated with shorter survival of mRCC patients receiving first-line TKI. The PLR may be an effective independent prognostic factor in this setting.

The Role of Cytoreductive Nephrectomy: European Association of Urology Recommendations in 2016

PATIENT SUMMARY

After the introduction of systemic targeted therapies, the use of nephrectomy in patients with metastatic renal cell carcinoma has declined. Currently, systemic therapy is offered to more patients first as a means to select those candidates that will likely benefit from removal of their primary tumour. Although studies consistently demonstrate a survival benefit after nephrectomy, most patients with poor risk metastatic disease are unlikely to benefit from surgery. Soon studies will report on the effect of nephrectomy in patients with metastatic disease at diagnosis.