Final Results From a Phase I Trial and Expansion Cohorts of Cabozantinib and Nivolumab Alone or With Ipilimumab for Advanced/Metastatic Genitourinary Tumors.

PURPOSE: Cabozantinib and nivolumab (CaboNivo) alone or with ipilimumab (CaboNivoIpi) have shown promising efficacy and safety in patients with metastatic urothelial carcinoma (mUC), metastatic renal cell carcinoma (mRCC), and rare genitourinary (GU) tumors in a dose-escalation phase I study. We report the final data analysis of the safety, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) of the phase I patients and seven expansion cohorts. METHODS: This is an investigator-initiated, multicenter, phase I trial. CaboNivo doublet expansion cohorts included (1) mUC, (2) mRCC, and (3) adenocarcinoma of the bladder/urachal; CaboNivoIpi triplet expansion cohorts included (1) mUC, (2) mRCC, (3) penile cancer, and (4) squamous cell carcinoma of the bladder and other rare GU tumors (ClinicalTrials.gov identifier: NCT02496208). RESULTS: The study enrolled 120 patients treated with CaboNivo (n = 64) or CaboNivoIpi (n = 56), with a median follow-up of 49.2 months. In 108 evaluable patients (CaboNivo n = 59; CaboNivoIpi n = 49), the ORR was 38% (complete response rate 11%) and the median duration of response was 20 months. The ORR was 42.4% for mUC, 62.5% for mRCC (n = 16), 85.7% for squamous cell carcinoma of the bladder (n = 7), 44.4% for penile cancer (n = 9), and 50.0% for renal medullary carcinoma (n = 2). Grade ≥ 3 treatment-related adverse events occurred in 84% of CaboNivo patients and 80% of CaboNivoIpi patients. CONCLUSION: CaboNivo and CaboNivoIpi demonstrated clinical activity and safety in patients with multiple GU malignancies, especially clear cell RCC, urothelial carcinoma, and rare GU tumors such as squamous cell carcinoma of the bladder, small cell carcinoma of the bladder, adenocarcinoma of the bladder, renal medullary carcinoma, and penile cancer.

Pathological concordance rate and outcomes by subtype in advanced papillary renal cell carcinoma.

OBJECTIVE: To evaluate the clinical significance of subtyping (type 1 vs 2) of papillary renal cell carcinoma (PRCC) in patients treated with targeted therapy, as well as the concordance, sensitivity and positive predictive value (PPV) of local review pathology review. METHODS: Patients with advanced refractory PRCC were randomised to receive sunitinib or cabozantinib, crizotinib or savolitinib, stratified by PRCC subtype (type 1, type 2, or not otherwise specified [NOS]/mixed) by local review. Central review was retrospectively conducted by three expert genitourinary pathologists who independently reviewed cases. The sensitivity and PPV of local review were estimated and outcomes [objective response rate (ORR), progression-free survival (PFS)] were summarised for treatment groups stratified by subtypes by central review. RESULTS: Amongst the 147 patients reviewed, the prevalence of individual subtypes varied by local or central review (type 1: 17.7% vs 29.3%; type 2: 53.1% vs 45.6%; NOS/mixed: 29.3% vs 25.2%), respectively. Individual cases were frequently reclassified and local pathology review demonstrated low sensitivity (type 1: 48%, 95% confidence interval [CI] 33, 65; type 2: 67%, 95% CI 55, 78; NOS/mixed: 43%, 95% CI 27, 61). The PPVs of local review were 80%, 57.7% and 37% for type 1, 2 and NOS/mixed, respectively. Compared to sunitinib, cabozantinib demonstrated improved PFS for both type 1 and type 2 PRCC subgroups (7.4 vs 9.0 and 2.9 vs 5.6 months, respectfully) as well as higher ORR. CONCLUSIONS: The PRCC subtype assignment did not identify a subset of patients with greater clinical benefit from cabozantinib, with significant discordance between local and central review. Our findings confirm the limited clinical value of pathological subtyping of metastatic PRCC, in line with the recent World Health Organisation 2022 guidelines. PATIENT SUMMARY: In this study, categorising papillary renal cell carcinoma into type 1 or 2 subtypes showed limited concordance between central and local pathological review and did not enrich for patients more likely to benefit from cabozantinib in the S1500 PAPMET trial.

Prevalence of Dietary Modification and Supplement Use in Patients with Metastatic Renal Cell Carcinoma Receiving Systemic Therapy.

Many patients diagnosed with cancer adopt dietary changes and supplement use, and a growing body of evidence suggests that such modifications can affect outcomes to cancer therapy. We sought to assess the prevalence of these practices and the surrounding physician-patient dialogue among patients with metastatic renal cell carcinoma. An online survey was administered by Kidney Cancer Research Alliance (KCCure), interrogating dietary modification patterns, supplement usage, out-of-pocket expenditure related to supplements, and patients' views toward alternative medicine practices. Patients with metastatic renal cell carcinoma receiving combination therapy were actively solicited. In total, 289 unique responses were collected. The most common first-line treatments were nivolumab/ipilimumab (32.4%) and axitinib/pembrolizumab (13.1%). Within the cohort, 147 (50.9%) started using supplements following diagnosis of renal cell carcinoma; the most utilized supplements were probiotics, cannabidiol (CBD) oil/marijuana, and Vitamin C, reported by 70 (47.6%), 61 (41.4%), and 54 (36.7%), respectively. Dietary modifications following cancer diagnosis were reported by 101 (34.9%) respondents, of which 19.8% followed the Mediterranean diet and 18.8% adopted a ketogenic diet. Most respondents (71.3%) noted that they consistently report supplement usage to their physicians. A substantial proportion of patients with metastatic renal cell carcinoma utilize dietary modification and supplements as an adjunct to antineoplastic therapy. Considering the widespread adoption of these practices and the reported effects on cancer treatment, it is crucial for healthcare providers to engage in discussions with patients regarding supplement use.

Cabozantinib and nivolumab with or without live bacterial supplementation in metastatic renal cell carcinoma: a randomized phase 1 trial.

Supplementation with CBM588, a bifidogenic live bacterial product, has been associated with improved clinical outcomes in persons with metastatic renal cell carcinoma (mRCC) receiving nivolumab and ipilimumab. However, its effect on those receiving tyrosine kinase inhibitor-based combinations is unknown. In this open-label, randomized, investigator-initiated, phase 1 study, 30 participants with locally advanced or mRCC with histological confirmation of clear cell, papillary or sarcomatoid component were randomized in a 2:1 fashion to receive cabozantinib (an inhibitor of vascular endothelial growth factor receptor, MET and AXL) and nivolumab (anti-programmed cell death protein 1) with or without CBM588 as first-line treatment. Metagenomic sequencing was performed on stool samples to characterize their gut microbiome at baseline and 13 weeks into treatment. The primary endpoint was a change in the relative abundance of Bifidobacterium spp.; secondary endpoints included objective response rate (ORR), progression-free survival (PFS) and toxicity profile. The primary endpoint of the study was not met and the addition of CBM588 to cabozantinib and nivolumab did not result in a difference in the relative abundance of Bifidobacterium spp. or alpha diversity (as measured by the Shannon index). However, ORR was significantly higher in participants treated with CBM588 compared to those in the control arm (14 of 19, 74% versus 2 of 10, 20%; P = 0.01). PFS at 6 months was 84% (16 of 19) and 60% (6 of 10) in the experimental and control arms, respectively. No significant difference in toxicity profile was seen between the study arms. Our results provide a preliminary signal of improved clinical activity with CBM588 in treatment-naive participants with mRCC receiving cabozantinib and nivolumab. Further investigation is needed to confirm these findings and better characterize the underlying mechanism driving this effect.ClinicalTrials.gov identifier: NCT05122546.

Adjuvant Everolimus in Patients with Completely Resected, Very High-risk Renal Cell Carcinoma of Clear Cell Histology: Results from the Phase 3 Placebo-controlled SWOG S0931 (EVEREST) Trial.

BACKGROUND AND OBJECTIVE: EVEREST is a phase 3 trial in patients with renal cell cancer (RCC) at intermediate-high or very high risk of recurrence after nephrectomy who were randomized to receive adjuvant everolimus or placebo. Longer recurrence-free survival (RFS) was observed with everolimus (hazard ratio [HR] 0.85, 95% confidence interval [CI] 0.72-1.00; p = 0.051), but the nominal significance level (p = 0.044) was not reached. To contextualize these results with positive phase 3 trials of adjuvant sunitinib and pembrolizumab, we conducted a secondary analysis in a similar population of EVEREST patients with very high-risk disease and clear cell histology. METHODS: Postnephrectomy patients with any clear cell component and very high-risk disease, defined as pT3a (grade 3-4), pT3b-c (any grade), T4 (any grade), or node-positive status (N+), were identified. A Cox regression model stratified by performance status was used to compare RFS and overall survival (OS) between the treatment arms. KEY FINDINGS AND LIMITATIONS: Of 1499 patients, 717 had clear cell histology and very high-risk disease; 699 met the eligibility criteria, of whom 348 were randomized to everolimus arm, and 351 to the placebo arm. Patient characteristics were similar between the arms. Only 163/348 (47%) patients in the everolimus arm completed all treatment as planned, versus 225/351 (64%) in the placebo arm. Adjuvant everolimus resulted in a statistically significant improvement in RFS (HR 0.80; 95%CI 0.65-0.99, p = 0.041). Evidence of a survival benefit was not seen (HR 0.85; 95%CI 0.64-1.14, p = 0.3) CONCLUSIONS AND CLINICAL IMPLICATIONS: In patients with clear cell RCC at very high-risk for recurrence, adjuvant everolimus resulted in significantly improved RFS compared to placebo but resulted in a high discontinuation rate due to adverse events. Although the treatment HR for OS was consistent with RFS findings, it did not reach statistical significance. With a focus on risk stratification tools and/or biomarkers to minimize toxicity risk in those not likely to benefit, this information can help inform the design of future adjuvant trials in high-risk RCC PATIENT SUMMARY: We assessed treatment with everolimus in comparison to placebo after complete surgical removal of clear-cell kidney cancer at very high risk of recurrence. We found that survival outcomes were better for patients treated with everolimus, although these patients had a higher rate of side effects.

Renal Cell Carcinoma of Variant Histology: New Biologic Understanding Leads to Therapeutic Advances.

Renal cell carcinoma (RCC) is one of the 10 most commonly diagnosed solid tumors. Most RCCs are histologically defined as clear cell, comprising approximately 75% of diagnoses. However, the remaining RCC cases are composed of a heterogeneous combination of diverse histopathologic subtypes, each with unique pathogeneses and clinical features. Although the therapeutic approach to both localized and metastatic RCCs has dramatically changed, first with the advent of antiangiogenic targeted therapies and more recently with the approval of immune checkpoint inhibitor (ICI)-based combinations, these advances have primarily benefited the clear cell RCC patient population. As such, there remains critical gaps in the optimization of treatment regimens for patients with non-clear cell, or variant, RCC histologies. Herein, we detail recent advances in understanding the biology of RCC with variant histology and how such findings have guided novel clinical studies investigating precision oncology approaches for these rare subtypes. Among the most common variant histology RCCs are papillary RCC, comprising approximately 15%-20% of all diagnoses. Although a histopathologically diverse subset of tumors, papillary RCC is canonically associated with amplification of the MET protooncogene; recently completed and ongoing trials have investigated MET-directed therapies for this patient population. Finally, we discuss the unique biology of RCC with sarcomatoid dedifferentiation and the recent clinical findings detailing its paradoxical sensitivity to ICIs.

Impact of renal cell carcinoma molecular subtypes on immunotherapy and targeted therapy outcomes.

Saliby et al. show that a machine learning approach can accurately classify clear cell renal cell carcinoma (RCC) into distinct molecular subtypes using transcriptomic data. When applied to tumors biospecimens from the JAVELIN Renal 101 (JR101) trial, a benefit is observed with immune checkpoint inhibitor (ICI)-based therapy across all molecular subtypes.

CD70-Targeted Allogeneic CAR T-Cell Therapy for Advanced Clear Cell Renal Cell Carcinoma.

Therapeutic approaches for clear cell renal cell carcinoma (ccRCC) remain limited; however, chimeric antigen receptor (CAR) T-cell therapies may offer novel treatment options. CTX130, an allogeneic CD70-targeting CAR T-cell product, was developed for the treatment of advanced or refractory ccRCC. We report that CTX130 showed favorable preclinical proliferation and cytotoxicity profiles and completely regressed RCC xenograft tumors. We also report results from 16 patients with relapsed/refractory ccRCC who received CTX130 in a phase I, multicenter, first-in-human clinical trial. No patients encountered dose-limiting toxicity, and disease control was achieved in 81.3% of patients. One patient remains in a durable complete response at 3 years. Finally, we report on a next-generation CAR T construct, CTX131, in which synergistic potency edits to CTX130 confer improved expansion and efficacy in preclinical studies. These data represent a proof of concept for the treatment of ccRCC and other CD70+ malignancies with CD70- targeted allogeneic CAR T cells. Significance: Although the role of CAR T cells is well established in hematologic malignancies, the clinical experience in solid tumors has been disappointing. This clinical trial demonstrates the first complete response in a patient with RCC, reinforcing the potential benefit of CAR T cells in the treatment of solid tumors.

Impact of Synchronous versus Metachronous Metastasis on Outcomes in Patients with Metastatic Renal Cell Carcinoma Treated with First-line Immune Checkpoint Inhibitor-based Combinations.

BACKGROUND AND OBJECTIVE: The impact of time of metastasis onset with respect toprimary renal cell carcinoma (RCC) diagnosis on survival outcomes is not well characterized in the era of immune checkpoint inhibitor (ICI)-based combinations. Herein, we assessed differences in clinical outcomes between synchronous and metachronous metastatic RCC (mRCC). METHODS: Data for patients with mRCC treated with first-line ICI-based combination therapies between 2014 and 2023 were retrospectively collected. Patients were categorized as having synchronous metastasis if present within 3 mo of RCC diagnosis; metachronous metastasis was defined as metastasis >3 mo after primary diagnosis. Time to treatment failure (TTF), overall survival (OS), and the disease control rate (DCR) were assessed. KEY FINDINGS AND LIMITATIONS: Our analysis included 223 eligible patients (126 synchronous and 97 metachronous). Median TTF did not significantly differ between the synchronous and metachronous groups (9 vs 19.8 mo; p = 0.063). Median OS was significantly shorter in the synchronous group (28.0 vs 50.9 mo; p = 0.001). Similarly, patients with synchronous metachronous metastasis (58.7% vs. 78.4%; p = 0.002). On multivariable analyses, synchronous metastasis remained independently associated with worse OS and DCR. CONCLUSIONS AND CLINICAL IMPLICATIONS: In this hypothesis-generating study, patients with mRCC with synchronous metastasis who were treated with first-line ICI-based combinations have a poorer OS and worse DCR than those with metachronous mRCC. If these results are externally validated, time to metastasis could be included in prognostic models for mRCC. PATIENT SUMMARY: Our study demonstrates that patients treated with current first-line immunotherapies, who present with metastasis at the initial diagnosis of kidney cancer have worse overall survival compared to those who develop metastasis later. These results can help physicians and patients understand life expectancy.

Randomized, Double-Blind Phase III Study of Pazopanib Versus Placebo in Patients With Metastatic Renal Cell Carcinoma Who Have No Evidence of Disease After Metastasectomy: ECOG-ACRIN E2810.

PURPOSE: Patients with no evidence of disease (NED) after metastasectomy for renal cell carcinoma are at high risk of recurrence. Pazopanib is an inhibitor of vascular endothelial growth factor receptor and other kinases that improves progression-free survival in patients with metastatic RCC (mRCC). We conducted a randomized, double-blind, placebo-controlled multicenter study to test whether pazopanib would improve disease-free survival (DFS) in patients with mRCC rendered NED after metastasectomy. PATIENTS AND METHODS: Patients with NED after metastasectomy were randomly assigned 1:1 to receive pazopanib 800 mg once daily versus placebo for 52 weeks. The study was designed to observe an improvement in DFS from 25% to 45% with pazopanib at 3 years, corresponding to 42% reduction in the DFS event rate. RESULTS: From August 2012 to July 2017, 129 patients were enrolled. The study was unblinded after 83 DFS events (92% information). The study did not meet its primary end point. An updated analysis at 60.5-month median follow-up from random assignment (95% CI, 59.3 to 71.0) showed that the 3-year DFS was 27.4% (95% CI, 17.9 to 41.7) for pazopanib and 21.9% (95% CI, 13.3 to 36.2) for placebo. Hazard ratio (HR) for DFS was 0.90 ([95% CI, 0.60 to 1.34]; Pone-sided = .29) in favor of pazopanib. Three-year overall survival (OS) was 81.9% (95% CI, 72.7 to 92.2) for pazopanib and 91.4% (95% CI, 84.4 to 98.9) for placebo. The HR for OS was 2.55 (95% CI, 1.23 to 5.27) in favor of placebo (Ptwo-sided = .012). Health-related quality-of-life measures deteriorated in the pazopanib group during the treatment period. CONCLUSION: Pazopanib did not improve DFS as the primary end point compared with blinded placebo in patients with mRCC with NED after metastasectomy. In addition, there was a concerning trend favoring placebo in OS.

Tumor Mutational Burden in Metastatic Castration-Resistant Prostate Cancer and Response to Checkpoint Inhibition.

This single-center cohort study assesses the association of tumor mutational burden status in patients with metastatic castration-resistant prostate cancer and response to immune checkpoint inhibitor therapy.

Long-Term Survival in Patients With Relapsed/Refractory Advanced Renal Cell Carcinoma Treated With Tivozanib: Analysis of the Phase III TIVO-3 Trial.

BACKGROUND: Tivozanib is an oral vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI) with efficacy in advanced renal cell carcinoma (RCC). Long-term exploratory analyses from the TIVO-3 trial in relapsed/refractory (R/R) RCC including patients (26%) with prior immuno-oncology (IO) therapy are reported. METHODS: Patients with R/R advanced RCC that progressed with 2 or 3 prior systemic therapies (≥1 VEGFR TKI) were randomized to tivozanib 1.5 mg QD or sorafenib 400 mg BID, stratified by IMDC risk and previous therapy. Safety, investigator-assessed long-term progression-free survival (LT-PFS), and serial overall survival (OS) were assessed. RESULTS: Mean time on treatment was 11.0 months with tivozanib (n = 175) and 6.3 months with sorafenib (n = 175). Fewer grade ≥3 treatment-related adverse events occurred with tivozanib (46%) than sorafenib (55%). Dose modification rates were lower with tivozanib than sorafenib across age/prior IO subgroups; prior IO therapy did not impact dose reductions or discontinuations in either arm. Landmark LT-PFS rates were higher with tivozanib (3 years: 12.3% vs 2.4%; 4 years: 7.6% vs 0%). After 22.8 months mean follow-up, the OS HR was 0.89 (95% CI, 0.70-1.14); when conditioned on 12-month landmark PFS, tivozanib showed significant OS improvement over sorafenib (HR, 0.45; 95% CI, 0.22-0.91; 2-sided P = .0221). CONCLUSIONS: Tivozanib demonstrated a consistent safety profile and long-term survival benefit in patients with R/R advanced RCC who were alive and progression free at 12 months. These post hoc exploratory analyses of LT-PFS and conditional OS support a clinically meaningful improvement with tivozanib versus sorafenib in this advanced RCC population.

Immuno-Oncology Advances in Genitourinary Cancers.

Immuno-oncology (IO) has made monumental gains in the past decade in the genitourinary space. In this review, we highlight advances with IO in renal cell carcinoma where it now has become standard-of-care frontline therapy in the metastatic setting but also discuss challenges with the initial approach. In urothelial carcinoma, we discuss the growing use of IO including exciting recent updates with IO-based regimens that may soon become the new standard of care. We further discuss difficulties with IO in prostate cancer, germ cell tumors, and penile squamous cell carcinoma. Finally, we highlight advances in IO approaches beyond checkpoint inhibition including the role of the gut microbiome and T-cell redirecting therapies.

Outcomes of Patients with Brain Metastases from Renal Cell Carcinoma Receiving First-line Therapies: Results from the International Metastatic Renal Cell Carcinoma Database Consortium.

Patients with brain metastases (BrM) from renal cell carcinoma and their outcomes are not well characterized owing to frequent exclusion of this population from clinical trials. We analyzed data for patients with or without BrM using the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC). A total of 389/4799 patients (8.1%) had BrM on initiation of systemic therapy. First-line immuno-oncology (IO)-based combination therapy was associated with longer median overall survival (OS; 32.7 mo, 95% confidence interval [CI] 22.3-not reached) versus tyrosine kinase inhibitor monotherapy (20.6 mo, 95% CI 15.7-24.5; p = 0.019), as were intensive focal therapies with stereotactic radiotherapy or neurosurgery (31.4 mo, 95% CI 22.3-37.5) versus whole-brain radiotherapy alone or no focal therapy (16.5 mo, 95% CI 10.2-21.1; p = 0.028). On multivariable analysis, IO-based regimens (HR 0.49, 95% CI 0.25-0.97; p = 0.040) and stereotactic radiotherapy or neurosurgery (HR 0.48, 95% CI 0.29-0.78; p = 0.003) were independently associated with longer OS, as was IMDC favorable or intermediate risk (HR 0.40, 95% CI 0.24-0.66; p < 0.001). Intensive systemic and focal therapies were associated with better prognosis in this population. Further studies should explore the clinical effectiveness of multimodal strategies. PATIENT SUMMARY: In a large group of patients with advanced kidney cancer, we found that 8.1% had brain metastases when starting systemic therapy. Patients with brain metastases had significantly poorer prognosis than those without brain metastases. Receipt of combination immunotherapy, stereotactic radiotherapy, or neurosurgery was associated with longer overall survival.

Assessment of eligibility criteria in renal cell carcinoma trials evaluating systemic therapy.

OBJECTIVES: To characterise the restrictiveness of eligibility criteria in contemporary renal cell carcinoma (RCC) trials, using recommendations from the American Society of Clinical Oncology (ASCO)-Friends of Cancer Research (FCR) initiative. METHODS: vPhase I-III trials assessing systemic therapies in patients with RCC starting between 30 June 2012 and 30 June 2022 were identified. Eligibility criteria regarding brain metastases, prior or concurrent malignancies, hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, and human immunodeficiency virus (HIV) infection were identified and stratified into three groups: exclusion, conditional inclusion, and not reported. Descriptive statistics were used to determine the frequency of eligibility criteria. Fisher's exact test or chi-square test were used to calculate their associations with certain trial characteristics. RESULTS: A total of 423 RCC trials were initially identified of which 112 (26.5%) had sufficient accessible information. Exclusion of patients with HIV infection, HBV/HCV infection, brain metastases, and prior or concurrent malignancies were reported in 74.1%, 53.6%, 33.0%, and 8.0% of trials, respectively. In the context of HIV and HBV/HCV infection, patients were largely excluded from trials evaluating immunotherapy (94.4% and 77.8%, respectively). In addition, brain metastases were excluded in trials assessing targeted therapy (36.4%), combined therapy (33.3%), and immunotherapy (22.2%). Exclusion of patients with prior or concurrent malignancies was less frequently reported, accounting for 9.1%, 8.3%, and 5.6% targeted therapy, combined therapy and immunotherapy trials, respectively. CONCLUSION: A substantial proportion of RCC trials utilise restrictive eligibility criteria, excluding patients with fairly prevalent comorbidities. Implementing the ASCO-FCR recommendations will ensure resulting data are more inclusive and aligned with patient populations in the real-world.

The 5th Kidney Cancer Research Summit: Research Accelerating Cures for Renal Cell Carcinoma in 2023.

The 5th Kidney Cancer Research Summit was a hybrid event hosted in Boston, MA in July 2023. As in previous editions, the conference attracted a wide representation of global thought leaders in kidney cancer spanning all stages of clinical and laboratory research. Sessions covered tumor metabolism, novel immune pathways, advances in clinical trials and immunotherapy, and progress toward biomarkers. The abstract presentations were published as a supplement in The Oncologist (https://academic.oup.com/oncolo/issue/28/Supplement_1). Aiming to be more concise than comprehensive, this commentary summarizes the most important emerging areas of kidney cancer research discussed and debated among the stakeholders at the conference, with relevant updates that have occurred since.

Characterization of Patients with Metastatic Renal Cell Carcinoma Undergoing Deferred, Upfront, or No Cytoreductive Nephrectomy in the Era of Combination Immunotherapy: Results from the International Metastatic Renal Cell Carcinoma Database Consortium.

BACKGROUND: The role of cytoreductive nephrectomy (CN) has not yet been well characterized in the era of combination immunotherapy. OBJECTIVE: To evaluate characteristics and outcomes for patients with metastatic renal cell carcinoma (mRCC) who received immuno-oncology (IO)-based combination therapy according to CN status. DESIGN, SETTING, AND PARTICIPANTS: Using the International mRCC Database Consortium (IMDC), patients with mRCC who received frontline IO-based combinations were included. Upfront CN was defined as CN up to 3 mo before diagnosis of metastatic disease but before systemic therapy initiation. Deferred CN was defined as CN after systemic therapy initiation. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS: Overall survival (OS) from initiation of systemic therapy was estimated via Cox proportional-hazards regression. A 12-mo landmark time and a time-varying covariate for CN status were used to mitigate potential bias. RESULTS AND LIMITATIONS: Of the 385 patients eligible for landmark analysis, 24, 182, and 179 underwent deferred CN, upfront CN, and no CN, respectively. Patients in the no CN subgroup were older (63 yr vs 57 yr in the deferred CN subgroup and 60 yr in the upfront CN subgroup; p = 0.001) and a higher proportion had bone metastases (44% vs 26% in the deferred CN subgroup and 23% in the upfront CN subgroup; p < 0.001). A lower proportion of patients in the upfront CN subgroup had IMDC poor risk (23% vs 43% in the no CN subgroup and 47% in the deferred CN subgroup; p < 0.001). On multivariable analysis, CN receipt was an independent favorable prognostic factor (hazard ratio 0.45, 95% confidence interval 0.26-0.78; p = 0.005). The study is limited by the lack of randomization and its retrospective nature. CONCLUSIONS: Despite changes in practice patterns with the advent of novel therapeutic agents, CN may still serve as an effective surgical intervention in carefully selected patients. PATIENT SUMMARY: For patients with metastatic kidney cancer, surgery to remove the primary tumor was traditionally the treatment of choice, but immunotherapy drugs are now another option for these patients. We analyzed data for contemporary patients with metastatic kidney cancer who received combination immunotherapy as their first treatment. We found that in selected patients receiving immunotherapy, surgery to remove the primary tumor as well can result in better prognosis.