Search

The role of upfront cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC) in the era of immune checkpoint inhibitors is unclear.To evaluate the relationship between upfront CN and clinical outcomes in the setting of mRCC treated with immune checkpoint inhibitors or targeted therapy.Using the International Metastatic RCC Database Consortium, we retrospectively identified patients diagnosed with de novo mRCC treated with immune checkpoint inhibitors or targeted therapy.Overall survival (OS) was compared between the two groups using the Kaplan-Meier method and multivariable Cox regressions adjusting for known prognostic factors.We identified a total of 4639 eligible patients with mRCC. Among the 4202 patients treated with targeted therapy and 437 patients treated with immune checkpoint inhibitors, 2326 (55%) and 234 (54%) patients received upfront CN prior to treatment start. In multivariable analyses, CN was associated with significantly better OS in both the immune checkpoint inhibitor-treated (hazard ratio [HR]: 0.61; 95% confidence interval [CI], 0.41-0.90, p = 0.013) and the targeted therapy treatment (HR: 0.72; 95% CI, 0.67-0.78, p 0.001) group. There was no difference in OS benefit of CN between the immune checkpoint inhibitor and targeted therapy treatment groups (interaction p = 0.6). Limitations include selection of patients from large academic centers and the retrospective nature of the study.Upfront CN is associated with a significant OS benefit in selected patients treated by either immune checkpoint inhibitors or targeted therapy, and still has a role in selected patients in the era of immune checkpoint inhibitors.Before effective systemic therapies were available for metastatic kidney cancer, surgical removal of the primary (kidney) tumor was the mainstay of treatment. The role of removing the primary tumor has recently been called into question given that more effective systemic therapies have become available. In this study, we find that removal of the primary kidney tumor still has a benefit for selected patients treated with highly effective modern systemic therapies, including targeted therapies and immune checkpoint inhibitors.

Supplementary Figures and Legends for Supplementary Tables

Prior data have variably implicated the inactivation of the mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) complex with increased tumor sensitivity to immune checkpoint inhibitors (ICI). Herein, we examined the association between mSWI/SNF variants and clinical outcomes to ICIs. We correlated somatic loss-of-function (LOF) variants in a predefined set of mSWI/SNF genes (ARID1A, ARID1B, SMARCA4, SMARCB1, PBRM1, and ARID2) with clinical outcomes in patients with cancer treated with systemic ICIs. We identified 676 patients from Dana-Farber Cancer Institute (DFCI, Boston, MA) and 848 patients from a publicly available database from Memorial Sloan Kettering Cancer Center (MSKCC, New York, NY) who met the inclusion criteria. Multivariable analyses were conducted and adjusted for available baseline factors and tumor mutational burden. Median follow-up was 19.6 (17.6–22.0) months and 28.0 (25.0–29.0) months for the DFCI and MSKCC cohorts, respectively. Seven solid tumor subtypes were examined. In the DFCI cohort, LOF variants of mSWI/SNF did not predict improved overall survival (OS), time-to-treatment failure (TTF), or disease control rate. Only patients with renal cell carcinoma with mSWI/SNF LOF showed significantly improved OS and TTF with adjusted HRs (95% confidence interval) of 0.33 (0.16–0.7) and 0.49 (0.27–0.88), respectively, and this was mostly driven by PRBM1. In the MSKCC cohort, where only OS was captured, LOF mSWI/SNF did not correlate with improved outcomes across any tumor subtype. We did not find a consistent association between mSWI/SNF LOF variants and improved clinical outcomes to ICIs, suggesting that mSWI/SNF variants should not be considered as biomarkers of response to ICIs.

Supplementary Tables

Purpose:Neuroendocrine prostate cancer (NEPC) is a resistance phenotype that emerges in men with metastatic castration-resistant prostate adenocarcinoma (CR-PRAD) and has important clinical implications, but is challenging to detect in practice. Herein, we report a novel tissue–informed epigenetic approach to noninvasively detect NEPC.Experimental Design:We first performed methylated immunoprecipitation and high-throughput sequencing (MeDIP-seq) on a training set of tumors, identified differentially methylated regions between NEPC and CR-PRAD, and built a model to predict the presence of NEPC (termed NEPC Risk Score). We then performed MeDIP-seq on cell-free DNA (cfDNA) from two independent cohorts of men with NEPC or CR-PRAD and assessed the accuracy of the model to predict the presence NEPC.Results:The test cohort comprised cfDNA samples from 48 men, 9 with NEPC and 39 with CR-PRAD. NEPC Risk Scores were significantly higher in men with NEPC than CR-PRAD (P = 4.3 × 10–7) and discriminated between NEPC and CR-PRAD with high accuracy (AUROC 0.96). The optimal NEPC Risk Score cutoff demonstrated 100% sensitivity and 90% specificity for detecting NEPC. The independent, multi-institutional validation cohort included cfDNA from 53 men, including 12 with NEPC and 41 with CR-PRAD. NEPC Risk Scores were significantly higher in men with NEPC than CR-PRAD (P = 7.5×10–12) and perfectly discriminated NEPC from CR-PRAD (AUROC 1.0). Applying the predefined NEPC Risk Score cutoff to the validation cohort resulted in 100% sensitivity and 95% specificity for detecting NEPC.Conclusions:Tissue-informed cfDNA methylation analysis is a promising approach for noninvasive detection of NEPC in men with advanced prostate cancer.

Supplementary Table from Detecting Neuroendocrine Prostate Cancer Through Tissue-Informed Cell-Free DNA Methylation Analysis

Supplementary Figure from Detecting Neuroendocrine Prostate Cancer Through Tissue-Informed Cell-Free DNA Methylation Analysis

Although therapeutic options for patients with advanced renal cell carcinoma (RCC) have increased in the past decade, no biomarkers are yet available for patient stratification or evaluation of therapy resistance. Given the dynamic and heterogeneous nature of clear cell RCC (ccRCC), tumor biopsies provide limited clinical utility, but liquid biopsies could overcome these limitations. Prior liquid biopsy approaches have lacked clinically relevant detection rates for patients with ccRCC. This study employed ccRCC‐specific markers, CAIX and CAXII, to identify circulating tumor cells (CTC) from patients with metastatic ccRCC. Distinct subtypes of ccRCC CTCs were evaluated for PD‐L1 and HLA‐I expression and correlated with patient response to therapy. CTC enumeration and expression of PD‐L1 and HLA‐I correlated with disease progression and treatment response, respectively. Longitudinal evaluation of a subset of patients demonstrated potential for CTC enumeration to serve as a pharmacodynamic biomarker. Further evaluation of phenotypic heterogeneity among CTCs is needed to better understand the clinical utility of this new biomarker., Circulating tumor cells (CTCs) were evaluated for their expression of programmed death ligand‐1 (PD‐L1) and human leukocyte antigen class I (HLA‐I), so that biomarkers of therapeutic resistance of clear cell renal cell carcinoma can be developed. CTCs were captured with antibody‐conjugated magnetic beads against EpCAM and CAIX then probed for CAXII and CK expression using microfluidic technology.

Metastatic castration-resistant prostate cancer is typically lethal, exhibiting intrinsic or acquired resistance to second-generation androgen-targeting therapies and minimal response to immune checkpoint inhibitors1. Cellular programs driving resistance in both cancer and immune cells remain poorly understood. We present single-cell transcriptomes from 14 patients with advanced prostate cancer, spanning all common metastatic sites. Irrespective of treatment exposure, adenocarcinoma cells pervasively coexpressed multiple androgen receptor isoforms, including truncated isoforms hypothesized to mediate resistance to androgen-targeting therapies2,3. Resistance to enzalutamide was associated with cancer cell–intrinsic epithelial–mesenchymal transition and transforming growth factor-β signaling. Small cell carcinoma cells exhibited divergent expression programs driven by transcriptional regulators promoting lineage plasticity and HOXB5, HOXB6 and NR1D2 (refs. 4–6). Additionally, a subset of patients had high expression of dysfunction markers on cytotoxic CD8+ T cells undergoing clonal expansion following enzalutamide treatment. Collectively, the transcriptional characterization of cancer and immune cells from human metastatic castration-resistant prostate cancer provides a basis for the development of therapeutic approaches complementing androgen signaling inhibition., Single-cell transcriptomic analysis of metastatic castration-resistant prostate cancer uncovers pervasive coexpression of androgen receptor isoforms and cancer cell–intrinsic and microenvironmental programs of treatment resistance

Prior data have variably implicated the inactivation of the mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) complex with increased tumor sensitivity to immune checkpoint inhibitors (ICI). Herein, we examined the association between mSWI/SNF variants and clinical outcomes to ICIs. We correlated somatic loss-of-function (LOF) variants in a predefined set of mSWI/SNF genes (ARID1A, ARID1B, SMARCA4, SMARCB1, PBRM1, and ARID2) with clinical outcomes in patients with cancer treated with systemic ICIs. We identified 676 patients from Dana-Farber Cancer Institute (DFCI, Boston, MA) and 848 patients from a publicly available database from Memorial Sloan Kettering Cancer Center (MSKCC, New York, NY) who met the inclusion criteria. Multivariable analyses were conducted and adjusted for available baseline factors and tumor mutational burden. Median follow-up was 19.6 (17.6–22.0) months and 28.0 (25.0–29.0) months for the DFCI and MSKCC cohorts, respectively. Seven solid tumor subtypes were examined. In the DFCI cohort, LOF variants of mSWI/SNF did not predict improved overall survival (OS), time-to-treatment failure (TTF), or disease control rate. Only patients with renal cell carcinoma with mSWI/SNF LOF showed significantly improved OS and TTF with adjusted HRs (95% confidence interval) of 0.33 (0.16–0.7) and 0.49 (0.27–0.88), respectively, and this was mostly driven by PRBM1. In the MSKCC cohort, where only OS was captured, LOF mSWI/SNF did not correlate with improved outcomes across any tumor subtype. We did not find a consistent association between mSWI/SNF LOF variants and improved clinical outcomes to ICIs, suggesting that mSWI/SNF variants should not be considered as biomarkers of response to ICIs.

Background Cabozantinib is approved for the first and subsequent line treatment of metastatic clear-cell renal cell carcinoma (ccRCC) based on trials in which most patients were immune checkpoint blockade (ICB) naive. With an expanding role of ICB in earlier lines of therapy, we assessed activity of cabozantinib in patients with metastatic ccRCC after progressing on anti-PD-1/PD-L1–based ICBs. Methods We retrospectively analysed the clinical outcomes of 86 patients from 2 academic centres who received cabozantinib after progression on ICB alone, ICB in combination with vascular endothelial growth factor inhibitors (VEGFis) or ICB in combination with other therapies. Overall response rate (ORR, investigator assessed), time to treatment failure (TTF), overall survival (OS) and toxicities leading to dose reductions or cessation were evaluated. Results Eighty-six patients were included in the analysis; the median age was 63 years (range 33–84) and the median number of prior therapies was 2 (range 1–10). The type of prior ICB therapy was ICBs alone (64%), an ICB in combination with a VEGFi (29%) or ICBs in combination with other therapies (7%). At the time of cabozantinib treatment, 71% of patients were in the International Metastatic RCC Database Consortium good- or intermediate-risk groups. Approximately half of patients (52%) were started on cabozantinib at the full 60 mg daily dose. The ORR was 36% (95% confidence interval [CI] = 26–47%) with no complete response and 43% achieving stable disease; 21% had primary progressive disease. The median TTF was 6.5 months (95% CI = 5.3–8.5.). The median OS was 13.1 months (95% CI = 8.7-NR) with 55% (95% CI = 41–66%) OS rate at 12 months. Most common reasons for dose reductions were fatigue (27%), palmar-plantar erythrodysesthesia (16%) and diarrhoea (10%). Conclusions Cabozantinib is active in patients treated with prior ICB-based therapies, with no new safety signals. This study supports the use of cabozantinib after ICB-based therapies.

Summary Background Data on patients with COVID-19 who have cancer are lacking. Here we characterise the outcomes of a cohort of patients with cancer and COVID-19 and identify potential prognostic factors for mortality and severe illness. Methods In this cohort study, we collected de-identified data on patients with active or previous malignancy, aged 18 years and older, with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection from the USA, Canada, and Spain from the COVID-19 and Cancer Consortium (CCC19) database for whom baseline data were added between March 17 and April 16, 2020. We collected data on baseline clinical conditions, medications, cancer diagnosis and treatment, and COVID-19 disease course. The primary endpoint was all-cause mortality within 30 days of diagnosis of COVID-19. We assessed the association between the outcome and potential prognostic variables using logistic regression analyses, partially adjusted for age, sex, smoking status, and obesity. This study is registered with ClinicalTrials.gov, NCT04354701, and is ongoing. Findings Of 1035 records entered into the CCC19 database during the study period, 928 patients met inclusion criteria for our analysis. Median age was 66 years (IQR 57–76), 279 (30%) were aged 75 years or older, and 468 (50%) patients were male. The most prevalent malignancies were breast (191 [21%]) and prostate (152 [16%]). 366 (39%) patients were on active anticancer treatment, and 396 (43%) had active (measurable) cancer. At analysis (May 7, 2020), 121 (13%) patients had died. In logistic regression analysis, independent factors associated with increased 30-day mortality, after partial adjustment, were: increased age (per 10 years; partially adjusted odds ratio 1·84, 95% CI 1·53–2·21), male sex (1·63, 1·07–2·48), smoking status (former smoker vs never smoked: 1·60, 1·03–2·47), number of comorbidities (two vs none: 4·50, 1·33–15·28), Eastern Cooperative Oncology Group performance status of 2 or higher (status of 2 vs 0 or 1: 3·89, 2·11–7·18), active cancer (progressing vs remission: 5·20, 2·77–9·77), and receipt of azithromycin plus hydroxychloroquine (vs treatment with neither: 2·93, 1·79–4·79; confounding by indication cannot be excluded). Compared with residence in the US-Northeast, residence in Canada (0·24, 0·07–0·84) or the US-Midwest (0·50, 0·28–0·90) were associated with decreased 30-day all-cause mortality. Race and ethnicity, obesity status, cancer type, type of anticancer therapy, and recent surgery were not associated with mortality. Interpretation Among patients with cancer and COVID-19, 30-day all-cause mortality was high and associated with general risk factors and risk factors unique to patients with cancer. Longer follow-up is needed to better understand the effect of COVID-19 on outcomes in patients with cancer, including the ability to continue specific cancer treatments. Funding American Cancer Society, National Institutes of Health, and Hope Foundation for Cancer Research.

PD-1 blockade has transformed the management of advanced clear cell renal cell carcinoma (ccRCC), but the drivers and resistors of the PD-1 response remain incompletely elucidated. Here, we analyzed 592 tumors from patients with advanced ccRCC enrolled in prospective clinical trials of treatment with PD-1 blockade by whole-exome and RNA sequencing, integrated with immunofluorescence analysis, to uncover the immunogenomic determinants of the therapeutic response. Although conventional genomic markers (such as tumor mutation burden and neoantigen load) and the degree of CD8+ T cell infiltration were not associated with clinical response, we discovered numerous chromosomal alterations associated with response or resistance to PD-1 blockade. These advanced ccRCC tumors were highly CD8+ T cell infiltrated, with only 27% having a non-infiltrated phenotype. Our analysis revealed that infiltrated tumors are depleted of favorable PBRM1 mutations and enriched for unfavorable chromosomal losses of 9p21.3, as compared with non-infiltrated tumors, demonstrating how the potential interplay of immunophenotypes with somatic alterations impacts therapeutic efficacy. A pooled genetic, transcriptomic and immunopathologic analysis of over 500 tumors from patients with advanced renal cell cancer suggests that response to PD-1 blockade depends on both CD8+ T cell infiltration and enrichment of tumor-intrinsic somatic alterations.

Background International Metastatic Renal Cell Carcinoma (mRCC) Database Consortium (IMDC) risk groups are important when considering therapeutic options for first-line treatment. Materials and Methods Adult patients with clear cell mRCC initiating first-line sunitinib between 2010 and 2018 were included in this retrospective database study. Median time to treatment discontinuation (TTD) and overall survival (OS) were estimated using Kaplan-Meier analysis. Outcomes were stratified by IMDC risk groups and evaluated for those in the combined intermediate and poor risk group and separately for those in the intermediate risk group with one versus two risk factors. Results Among 1,769 patients treated with first-line sunitinib, 318 (18%) had favorable, 1,031 (58%) had intermediate, and 420 (24%) had poor IMDC risk. Across the three risk groups, patients had similar age, gender, and sunitinib initiation year. Median TTD was 15.0, 8.5, and 4.2 months in the favorable, intermediate, and poor risk groups, respectively, and 7.1 months in the combined intermediate and poor risk group. Median OS was 52.1, 31.5, and 9.8 months in the favorable, intermediate, and poor risk groups, respectively, and 23.2 months in the combined intermediate and poor risk group. Median OS (35.1 vs. 21.9 months) and TTD (10.3 vs. 6.6 months) were significantly different between intermediate risk patients with one versus two risk factors. Conclusion This real-world study found a median OS of 52 months for patients with favorable IMDC risk treated with first-line sunitinib, setting a new benchmark on clinical outcomes of clear cell mRCC. Analysis of intermediate risk group by one or two risk factors demonstrated distinct clinical outcomes. Implications for Practice This analysis offers a contemporary benchmark for overall survival (median, 52.1 months; 95% confidence interval, 43.4–61.2) among patients with clear cell metastatic renal cell carcinoma who were treated with sunitinib as first-line therapy in a real-world setting and classified as favorable risk according to International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk group classification. This study demonstrates that clinical outcomes differ between IMDC risk groups as well as within the intermediate risk group based on the number of risk factors, thus warranting further consideration of risk group when counseling patients about therapeutic options and designing clinical trials.

Key Points Question Given the higher COVID-19–related mortality rate observed among men than among women, is androgen deprivation therapy associated with decreased rate of 30-day mortality from COVID-19 among patients with prostate cancer? Findings In this cohort study of 1106 patients, no statistically significant difference was found in the rates of all cause 30-day mortality following COVID-19 infection among men with prostate cancer receiving androgen deprivation therapy (15%) vs those not receiving androgen deprivation therapy (14%). Meaning The findings of this cohort study do not support an association between androgen deprivation therapy and 30-day mortality among patients with COVID-19 infection., Importance Androgen deprivation therapy (ADT) has been theorized to decrease the severity of SARS-CoV-2 infection in patients with prostate cancer owing to a potential decrease in the tissue-based expression of the SARS-CoV-2 coreceptor transmembrane protease, serine 2 (TMPRSS2). Objective To examine whether ADT is associated with a decreased rate of 30-day mortality from SARS-CoV-2 infection among patients with prostate cancer. Design, Setting, and Participants This cohort study analyzed patient data recorded in the COVID-19 and Cancer Consortium registry between March 17, 2020, and February 11, 2021. The consortium maintains a centralized multi-institution registry of patients with a current or past diagnosis of cancer who developed COVID-19. Data were collected and managed using REDCap software hosted at Vanderbilt University Medical Center in Nashville, Tennessee. Initially, 1228 patients aged 18 years or older with prostate cancer listed as their primary malignant neoplasm were included; 122 patients with a second malignant neoplasm, insufficient follow-up, or low-quality data were excluded. Propensity matching was performed using the nearest-neighbor method with a 1:3 ratio of treated units to control units, adjusted for age, body mass index, race and ethnicity, Eastern Cooperative Oncology Group performance status score, smoking status, comorbidities (cardiovascular, pulmonary, kidney disease, and diabetes), cancer status, baseline steroid use, COVID-19 treatment, and presence of metastatic disease. Exposures Androgen deprivation therapy use was defined as prior bilateral orchiectomy or pharmacologic ADT administered within the prior 3 months of presentation with COVID-19. Main Outcomes and Measures The primary outcome was the rate of all-cause 30-day mortality after COVID-19 diagnosis for patients receiving ADT compared with patients not receiving ADT after propensity matching. Results After exclusions, 1106 patients with prostate cancer (before propensity score matching: median age, 73 years [IQR, 65-79 years]; 561 (51%) self-identified as non-Hispanic White) were included for analysis. Of these patients, 477 were included for propensity score matching (169 who received ADT and 308 who did not receive ADT). After propensity matching, there was no significant difference in the primary end point of the rate of all-cause 30-day mortality (OR, 0.77; 95% CI, 0.42-1.42). Conclusions and Relevance Findings from this cohort study suggest that ADT use was not associated with decreased mortality from SARS-CoV-2 infection. However, large ongoing clinical trials will provide further evidence on the role of ADT or other androgen-targeted therapies in reducing COVID-19 infection severity., This cohort study using data from the COVID-19 and Cancer Consortium registry examines whether androgen deprivation therapy is associated with decreased rates of mortality within 30 days of COVID-19 diagnosis among patients with prostate cancer.

Translocation renal cell carcinoma (tRCC) is an aggressive and poorly-characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 tRCC patients identified across multiple genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to many targeted therapies. Consistently, we find that outcomes for tRCC patients treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKI) are worse than those treated with immune checkpoint inhibition (ICI). Multiparametric immunofluorescence confirmed the presence of CD8 + tumor-infiltrating T cells compatible with a clinical benefit from ICI and revealed an exhaustion immunophenotype distinct from clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.

Introduction Patients with lung cancer (LC) are susceptible to severe outcomes from COVID-19. This study evaluated disruption to care of patients with LC during the COVID-19 pandemic. Methods The COVID-19 and Cancer Outcomes Study (CCOS) is a prospective cohort study comprised of patients with a current or past history of hematological or solid malignancies with outpatient visits between March 2 and March 6, 2020, at two academic cancer centers in the Northeastern United States (US). Data was collected for the three months prior to the index week (baseline period) and the following three months (pandemic period). Results 313 of 2365 patients had LC, 1578 had other solid tumors, and 474 had hematological malignancies. Patients with LC were not at increased risk of COVID-19 diagnosis compared to patients with other solid or hematological malignancies. When comparing data from the pandemic period to the baseline period, patients with LC were more likely to have a decrease in in-person visits compared to patients with other solid tumors (aOR 1.94; 95% CI, 1.46–2.58), but without an increase in telehealth visits (aOR 1.13; 95% CI 0.85–1.50). Patients with LC were more likely to experience pandemic-related treatment delays than patients with other solid tumors (aOR 1.80; 95% CI 1.13–2.80) and were more likely to experience imaging/diagnostic procedure delays than patients with other solid tumors (aOR 2.59; 95% CI, 1.46–4.47) and hematological malignancies (aOR 2.01; 95% CI, 1.02–3.93). Among patients on systemic therapy, patients with LC were also at increased risk for decreased in-person visits and increased treatment delays compared to those with other solid tumors. Discussion Patients with LC experienced increased cancer care disruption compared to patients with other malignancies during the early phase of the COVID-19 pandemic. Focused efforts to ensure continuity of care for this patient population are warranted.

Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings build on prior work and shed light on the molecular drivers of aggressivity and responsiveness to ICI of S/R RCC., Sarcomatoid and rhabdoid tumours are highly aggressive forms of renal cell carcinoma that are also responsive to immunotherapy. In this study, the authors perform a comprehensive molecular characterization of these tumours discovering an enrichment of specific alterations and an inflamed phenotype.

BackgroundCD73–adenosine signaling in the tumor microenvironment is immunosuppressive and may be associated with aggressive renal cell carcinoma (RCC). We investigated the prognostic significance of CD73 protein expression in RCC leveraging nephrectomy samples. We also performed a complementary analysis using The Cancer Genome Atlas (TCGA) dataset to evaluate the correlation of CD73 (ecto-5′-nucleotidase (NT5E), CD39 (ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1)) and A2 adenosine receptor (A2AR;ADORA2A) transcript levels with markers of angiogenesis and antitumor immune response.MethodsPatients with RCC with available archived nephrectomy samples were eligible for inclusion. Tumor CD73 protein expression was assessed by immunohistochemistry and quantified using a combined score (CS: % positive cells×intensity). Samples were categorized as CD73negative(CS=0), CD73lowor CD73high(< and ≥median CS, respectively). Multivariable Cox regression analysis compared disease-free survival (DFS) and overall survival (OS) between CD73 expression groups. In the TCGA dataset, samples were categorized as low, intermediate and highNT5E,ENTPD1andADORA2Agene expression groups. Gene expression signatures for infiltrating immune cells, angiogenesis, myeloid inflammation, and effector T-cell response were compared betweenNT5E,ENTPD1andADORA2Aexpression groups.ResultsAmong the 138 patients eligible for inclusion, ‘any’ CD73 expression was observed in 30% of primary tumor samples. High CD73 expression was more frequent in patients with M1 RCC (29% vs 12% M0), grade 4 tumors (27% vs 13% grade 3 vs 15% grades 1 and 2), advanced T-stage (≥T3: 22% vs T2: 19% vs T1: 12%) and tumors with sarcomatoid histology (50% vs 12%). In the M0 cohort (n=107), patients with CD73hightumor expression had significantly worse 5-year DFS (42%) and 10-year OS (22%) compared with those in the CD73negativegroup (DFS: 75%, adjusted HR: 2.7, 95% CI 1.3 to 5.9, p=0.01; OS: 64%, adjusted HR: 2.6, 95% CI 1.2 to 5.8, p=0.02) independent of tumor stage and grade. In the TCGA analysis, highNT5Eexpression was associated with significantly worse 5-year OS (p=0.008).NT5EandENTPD1expression correlated with higher regulatory T cell (Treg) signature, whileADORA2Aexpression was associated with increased Treg and angiogenesis signatures.ConclusionsHigh CD73 expression portends significantly worse survival outcomes independent of stage and grade. Our findings provide compelling support for targeting the immunosuppressive and proangiogenic CD73–adenosine pathway in RCC.

Summary Immune checkpoint blockade (ICB) results in durable disease control in a subset of patients with advanced renal cell carcinoma (RCC), but mechanisms driving resistance are poorly understood. We characterize the single-cell transcriptomes of cancer and immune cells from metastatic RCC patients before or after ICB exposure. In responders, subsets of cytotoxic T cells express higher levels of co-inhibitory receptors and effector molecules. Macrophages from treated biopsies shift toward pro-inflammatory states in response to an interferon-rich microenvironment but also upregulate immunosuppressive markers. In cancer cells, we identify bifurcation into two subpopulations differing in angiogenic signaling and upregulation of immunosuppressive programs after ICB. Expression signatures for cancer cell subpopulations and immune evasion are associated with PBRM1 mutation and survival in primary and ICB-treated advanced RCC. Our findings demonstrate that ICB remodels the RCC microenvironment and modifies the interplay between cancer and immune cell populations critical for understanding response and resistance to ICB., Graphical abstract, Highlights • Distinct CD8+ T cell phenotypes are enriched after immune checkpoint blockade (ICB) • Immune checkpoint ligands are upregulated in macrophages and tumor cells after ICB • Two cancer cell subpopulations are conserved across heterogeneous RCC tumors • Cancer cell programs drive distinct immune interactions and predict patient outcomes, Bi et al. dissect the cancer cell and immune microenvironmental transcriptional programs in immune checkpoint blockade-exposed metastatic renal cell carcinoma, revealing immune subpopulation reprogramming and interactions with distinct cancer cell populations in the context of clinical resistance.

Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors1–3, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings shed light on the molecular drivers of aggressivity and responsiveness to immune checkpoint inhibitors of S/R RCC tumors.

Purpose: Neuroendocrine prostate cancer (NEPC) is a resistance phenotype that emerges in men with metastatic castration-resistant prostate adenocarcinoma (CR-PRAD) and has important clinical implications, but is challenging to detect in practice. Herein, we report a novel tissue–informed epigenetic approach to noninvasively detect NEPC. Experimental Design: We first performed methylated immunoprecipitation and high-throughput sequencing (MeDIP-seq) on a training set of tumors, identified differentially methylated regions between NEPC and CR-PRAD, and built a model to predict the presence of NEPC (termed NEPC Risk Score). We then performed MeDIP-seq on cell-free DNA (cfDNA) from two independent cohorts of men with NEPC or CR-PRAD and assessed the accuracy of the model to predict the presence NEPC. Results: The test cohort comprised cfDNA samples from 48 men, 9 with NEPC and 39 with CR-PRAD. NEPC Risk Scores were significantly higher in men with NEPC than CR-PRAD (P = 4.3 × 10–7) and discriminated between NEPC and CR-PRAD with high accuracy (AUROC 0.96). The optimal NEPC Risk Score cutoff demonstrated 100% sensitivity and 90% specificity for detecting NEPC. The independent, multi-institutional validation cohort included cfDNA from 53 men, including 12 with NEPC and 41 with CR-PRAD. NEPC Risk Scores were significantly higher in men with NEPC than CR-PRAD (P = 7.5×10–12) and perfectly discriminated NEPC from CR-PRAD (AUROC 1.0). Applying the predefined NEPC Risk Score cutoff to the validation cohort resulted in 100% sensitivity and 95% specificity for detecting NEPC. Conclusions: Tissue-informed cfDNA methylation analysis is a promising approach for noninvasive detection of NEPC in men with advanced prostate cancer.

Translocation renal cell carcinoma (tRCC) is a poorly-characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 patients with tRCC identified across genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to targeted therapies. Consistently, we find that outcomes for patients with tRCC treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKI) are worse than those treated with immune checkpoint inhibition (ICI). Using multiparametric immunofluorescence, we find that the tumors are infiltrated with CD8(+) T cells, though the T cells harbor an exhaustion immunophenotype distinct from that of clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.

PURPOSE In this multicenter phase II trial, we evaluated atezolizumab combined with bevacizumab in patients with advanced renal cell carcinoma (RCC) with variant histology or any RCC histology with ≥ 20% sarcomatoid differentiation. PATIENTS AND METHODS Eligible patients may have received previous systemic therapy, excluding prior bevacizumab or checkpoint inhibitors. Patients underwent a baseline biopsy and received atezolizumab 1,200 mg and bevacizumab 15 mg/kg intravenously every 3 weeks. The primary end point was overall response rate (ORR) by RECIST version 1.1. Additional end points were progression-free survival (PFS), toxicity, biomarkers of response as determined by programmed death-ligand 1 (PD-L1) status, and on-therapy quality-of-life (QOL) metrics using the Functional Assessment of Cancer Therapy Kidney Symptom Index-19 and the Brief Fatigue Inventory. RESULTS Sixty patients received at least 1 dose of either study agent; the majority (65%) were treatment naïve. The ORR for the overall population was 33% and 50% in patients with clear cell RCC with sarcomatoid differentiation and 26% in patients with variant histology RCC. Median PFS was 8.3 months (95% CI, 5.7 to 10.9 months). PD-L1 status was available for 36 patients; 15 (42%) had ≥ 1% expression on tumor cells. ORR in PD-L1–positive patients was 60% (n = 9) v 19% (n = 4) in PD-L1–negative patients. Eight patients (13%) developed treatment-related grade 3 toxicities. There were no treatment-related grade 4-5 toxicities. QOL was maintained throughout therapy. CONCLUSION In this study, atezolizumab and bevacizumab demonstrated safety and resulted in objective responses in patients with variant histology RCC or RCC with ≥ 20% sarcomatoid differentiation. This regimen warrants additional exploration in patients with rare RCC, particularly those with PD-L1–positive tumors.

Improving early cancer detection has the potential to substantially reduce cancer-related mortality. Cell-free methylated DNA immunoprecipitation and high-throughput sequencing (cfMeDIP-seq) is a highly sensitive assay capable of detecting early-stage tumors. We report accurate classification of patients across all stages of renal cell carcinoma (RCC) in plasma (area under the receiver operating characteristic (AUROC) curve of 0.99) and demonstrate the validity of this assay to identify patients with RCC using urine cell-free DNA (cfDNA; AUROC of 0.86).

Background Antibiotic use alters commensal gut microbiota, which is a key regulator of immune homeostasis. Objective To investigate the impact of antibiotic use on clinical outcomes in metastatic renal cell carcinoma (mRCC) patients treated with systemic agents. Design, setting, and participants We analyzed two cohorts: an institutional cohort (n = 146) receiving programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1)-based immune checkpoint inhibitors (ICIs) and a trial-database cohort (n = 4144) receiving interferon-α (n = 510), mammalian target of rapamycin (mTOR) inhibitors (n = 660), and vascular endothelial growth factor targeted therapies (VEGF-TT; n = 2974) on phase II/III clinical trials. Outcomes measurements and statistical analysis The association of antibiotic use (defined as use from 8 wk before to 4 wk after the initiation of anticancer therapy) with progression-free survival (PFS) and overall survival (OS) was evaluated using Cox regression, adjusted for known prognostic factors including International Metastatic RCC Database Consortium risk factors. Results and limitations Most patients were male, had clear cell histology, and were at an intermediate risk. Overall, in the institutional cohort, objective response rate (ORR) was 30%, PFS was 7.2 mo, and 1-yr OS was 77%. Antibiotic users (n = 31, 21%) had a lower ORR (12.9% vs 34.8%, p = 0.026) and shorter PFS (adjusted hazard ratio [HR] = 1.96, 95% confidence interval [CI] 1.20–3.20, p = 0.007) than antibiotic nonusers. In the trial-database cohort, antibiotic use (n = 709, 17%) adversely impacted OS in patients treated with interferon (HR = 1.62, 95% CI 1.13–2.31, p = 0.008) or with VEGF-TT and prior cytokines (HR = 1.65, 95% CI 1.04–2.62, p = 0.033), but not patients treated with mTOR inhibitors or VEGF-TT without prior cytokines. Limitations include retrospective design, and limited details regarding concomitant medications and antibiotic indication/duration. Conclusions Antibiotic use appears to reduce the efficacy of immunotherapy-based regimens in mRCC. The modulation of gut microbiota may play an important role in optimizing outcomes of patients treated with ICIs. Patient summary We evaluated metastatic renal cell carcinoma patients and found that those who were treated with immunotherapy had worse outcomes if they also received antibiotics at the start of treatment. This study highlights the importance of judicious antibiotic use.

The tumor immune microenvironment plays a critical role in cancer progression and response to immunotherapy in clear cell renal cell carcinoma (ccRCC), yet the composition and phenotypic states of immune cells in this tumor are incompletely characterized. We performed single-cell RNA and T cell receptor sequencing (scRNA-seq/scTCR-seq) on 164,722 individual cells from tumor and adjacent non-tumor tissue in patients with ccRCC across disease stages – early, locally advanced, and advanced/metastatic. Terminally exhausted CD8(+) T cells were enriched in metastatic disease and were restricted in TCR diversity. Within the myeloid compartment, pro-inflammatory macrophages were decreased, and suppressive M2-like macrophages were increased in advanced disease. Terminally exhausted CD8(+) T cells and M2-like macrophages co-occurred in advanced disease and expressed ligands and receptors that support T cell dysfunction and M2-like polarization. This immune dysfunction circuit is associated with a worse prognosis in external cohorts and identifies potentially targetable immune inhibitory pathways in ccRCC.

Introduction: Patients with thoracic malignancies are susceptible to severe outcomes from coronavirus disease 2019 (COVID-19). The aim of this study was to evaluate the disruption to care of patients with thoracic malignancies during the COVID-19 pandemic. Methods: The COVID-19 and Cancer Outcomes Study (CCOS) is a multicenter prospective cohort study comprised of adult patients with a current or past history of hematological malignancy or invasive solid tumor who had an outpatient medical oncology visit on the index week between March 2 and March 6, 2020 at the Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai in New York, NY (MSSM) or the Dana-Farber Cancer Institute in Boston, MA (DFCI). An electronic data capture platform was used to collect patient-, cancer-, and treatment-related variables during the three months prior to the index week (the baseline period) and the following three months (the pandemic period). Two-by-three contingency tables with Fisher’s exact tests were computed. All tests were two-tailed and considered statistically significant for p Citation Format: Sheena Bhalla, Ziad Bakouny, Andrew L. Schmidt, John A. Steinharter, Douglas A. Tremblay, Mark M. Awad, Alaina J. Kessler, Robert I. Haddad, Michelle Evans, Fiona Busser, Michael Wotman, Catherine R. Curran, Brittney S. Zimmerman, Gabrielle Bouchard, Tomi Jun, Pier V. Nuzzo, Qian Qin, Laure Hirsch, Jonathan Feld, Kaitlin M Kelleher, Danielle Seidman, Hsin-Hui Huang, Chris Labaki, Heather M. Anderson-Keightly, Sarah Abou Alaiwi, Talia D. Rosenbloom, Penina S. Stewart, Matthew D. Galsky, Toni K. Choueiri, Deborah B. Doroshow. Disruption to care of patients with thoracic malignancies: A COVID-19 and cancer outcomes study [abstract]. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2021 Feb 3-5. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(6_Suppl):Abstract nr S06-02.

Background: The COVID-19 pandemic has rapidly altered cancer care However, the ways in which it has done so and the associated impact at the individual and societal levels remains poorly defined Methods: CCOS is a multicenter prospective cohort study designed to define the impact of the pandemic on cancer care delivery and outcomes The CCOS cohort comprised consecutive outpatients with cancer seen at two US cancer centers from March 2 to March 6, 2020 (index visit) Data was collected at baseline, retrospectively from the preceding 3 months, and prospectively at 3-month follow up Per patient changes in numbers of visits were compared using Wilcoxon signed rank tests Correlates of increases in telehealth visits and decreases in in-person visits were evaluated using multivariable logistic regression models Adjusted Odds ratios [aOR] and 95% confidence intervals (CI) were reported Results: Of 2365 included patients, 1219 (51 6%) had a decrease in in-person visit frequency during the pandemic period relative to the preceding 3 months Conversely, 760 (32 2%) had an increased frequency of telehealth visits (decrease in in-person and increase in telehealth visits;both p

5046 Background: Methylation profiling of circulating cell-free DNA (cfDNA) is a promising approach for non-invasive tumor detection due to the presence of tissue-specific epigenetic signatures that are detectable in cfDNA. Cell-free methylated DNA immunoprecipitation and high-throughput sequencing (cfMedDIP-seq) is a sensitive, low-input, cost-effective, bisulfite-free approach to profiling cfDNA methylomes, capable of detecting and classifying various tumor types. We tested the feasibility of cfMeDIP-seq to detect urothelial carcinoma (UC) in plasma samples. Methods: We performed cfMeDIP-seq on plasma samples from 43 patients (pts): 18 metastatic UC (UC) pts, 12 pre-cystectomy non-metastatic UC pts, and 13 cancer-free controls. Six (50%) of pre-cystectomy cases were non-muscle invasive UC. cfDNA was immunoprecipitated and enriched using an antibody targeting 5-methylcytosine and PCR-amplified to create a sequence-ready library. The top differentially methylated regions (DMRs) between UC and control samples were used to train a regularized binomial generalized linear model using 80% of the samples as a training set. The 20% of withheld test samples were then assigned a probability of being UC or control. This process was repeated 100 times. Results: The average amount (standard deviation) of cfDNA isolated from 1 ml of UC plasma samples was 29.2 (27.4) ng/µL and 8.02 (3.58) ng/µL in cancer-free controls. We identified 9,826 DMRs in plasma samples at an adjusted p-value of < 0.01, which partitioned UC and control samples. Iterative training and classification of held out samples using the top 300 DMRs resulted in a mean AUROC of 0.987. Conclusions: cfMeDIP-seq is an interesting new approach for non-invasive detection of UC. cfMeDIP-seq demonstrates high sensitivity to detect UC across all stages of UC, including non-muscle invasive disease.

e17565 Background: We previously reported the significant prognostic and predictive utility of pretreatment serum PD-L1 in the CCTG MA.31 breast cancer serum bank (SABCS 2018, abstr PD3-10). IL-8 (CXCL8) is a pro-inflammatory cytokine that binds to CXCR1 and CXCR2 and promotes tumor immune escape and progression. High serum IL-8 levels are associated with poor prognosis in many cancers, and have recently been reported to predict for reduced overall survival (OS) to nivolumab in lung cancer and melanoma (ASCO 2018, abstr #3025). Here we correlated plasma IL-8 and PD-L1 levels with OS in mCRPC patients. Methods: 201 metastatic CRPC patients had EDTA plasma available for this retrospective analysis. Patient eligibility included chemotherapy-naive mCRPC patients. The ELLA immunoassay platform (ProteinSimple, San Jose, CA) was utilized to quantitate plasma IL-8 and PD-L1. Cox regression assessed hazard ratio (HR) for OS using both categorical (median) and continuous (log-transformed) biomarkers. Results: In univariate analysis, higher plasma IL-8 levels were significantly associated with reduced OS when analyzed as a continuous variable (HR = 1.53; p = 0.003) and were of borderline significance at the median cutpoint (HR = 1.32; p = 0.069; 20.9 vs 31.5 mos median OS). Plasma PD-L1 levels were not significantly associated with OS when analyzed as a continuous variable (p = 0.17), but increased levels were significant when analyzed at the median cutpoint (HR = 1.36; p = 0.044; 21.9 vs 29.0 mos median OS). When plasma IL-8 and PD-L1 levels were combined (median cutpoints), plasma IL-8 high / PD-L1 high patients (n = 58) had a significantly shorter OS vs the plasma IL-8 low / PD-L1 low patients (n = 58) (HR = 1.69; p = 0.009; 19.3 vs 32.9 mos median OS, respectively). In multivariate analysis, when adjusted for biopsy Gleason score, age, PSA, and ECOG PS (all at time of blood draw), only high plasma IL-8 (on a continuous basis) was significantly associated with reduced OS (HR = 1.43; p = 0.019). Conclusions: In mCRPC patients, high plasma IL-8 and PD-L1 levels were associated with reduced OS (separately and combined). Circulating IL-8 and PD-L1 evaluation may inform prognosis in mCRPC and could be considered as biomarkers in future studies determining response to immune checkpoint inhibitor and anti-IL8 therapy.

608 Background: The role of CN for mRCC treated with ICI is not well defined. Our aim was to evaluate the role of CN for mRCC treated by ICI or TT using a propensity score-based analysis. Methods: We retrospectively assessed patients who were diagnosed with de novo mRCC and who had started first line systemic therapy (ICI or TT) between 2009 and 2019 using the International Metastatic RCC Database Consortium (IMDC). Overall Survival (OS) was compared between patients receiving CN and those treated by systemic therapies alone, using the Kaplan-Meier method and Cox regressions, in the TT and ICI arms separately. In order to account for treatment selection bias, inverse probability of treatment weighting (IPTW) of propensity scores, based on 14 confounding variables, was used and variables were considered balanced if standardized mean difference (SMD) < 0.1. For variables with SMD≥0.1, residual confounding was adjusted for using multivariable models. Results: 3856 patients had been treated by TT (2470 CN+ & 1386 CN-) and 198 by ICI (143 CN+ & 55 CN-). Median follow-up was 38.5 months. After IPTW, baseline characteristics were largely balanced between the CN+ and CN- arms, in the TT and ICI groups (14/14 and 12/14 with SMD < 0.1, respectively). CN was associated with significantly improved OS in both the ICI (Hazard Ratio [HR] = 0.39 [0.19-0.83]) and TT (HR = 0.56 [0.51-0.62]) groups. The interaction term between CN and therapy type (ICI vs TT) was not statistically significant (p = 0.43). The point estimates of the HRs were consistent in sensitivity analyses using multivariable models. Conclusions: In a propensity score-based analysis, CN was found to be associated with a significant OS benefit in patients treated by either ICI or TT. While this study is not a substitute for randomized controlled trials (e.g. CARMENA), the results suggest that CN may still play a role in selected patients in the ICI era.[Table: see text]

715 Background: S/R RCC are highly aggressive tumors but recent pilot clinical data have suggested that these tumors respond well to ICI. Our aim was to perform integrative molecular characterization of S/R RCC tumors in order to characterize potential features that underlie their poor prognosis and responses to ICI. Methods: We compared genomic (1), transcriptomic (2) and immune microenvironment (3) data between S/R and non-S/R tumors. (1) S/R patients from 3 cohorts [N = 209]: The Cancer Genome Atlas [TCGA], CheckMate 010/025 & panel sequencing from Dana-Farber/Harvard Cancer Center [DF/HCC]. (2) RNA-seq on S/R from 2 cohorts [N = 98]: TCGA & CheckMate 010/025. (3) Immunofluorescence for CD8+ T cells [N = 17] & Immunohistochemistry for PD-L1 expression on tumor cells [N = 118] from CheckMate 010/025. Overall Response Rate (ORR), Progression Free Survival (PFS), and Overall Survival (OS) in S/R RCC was compared between ICI and non-ICI in clinical cohorts (Table). Results: S/R tumors were significantly enriched in mutations in BAP1, NF2, RELN, and MUTYH, deletions of CDKN2A/B & amplifications of EZH2 (q < 0.05) compared to non-S/R tumors. Gene Set Enrichment Analysis showed upregulation of epithelial-mesenchymal transition, immune pathways, and proliferation programs compared to non-S/R tumors in both RNA-seq cohorts independently (q < 0.25). S/R tumors exhibited greater infiltration by CD8+ T cells at the tumor margin (p = 0.048) and PD-L1 expression on tumor cells (43.2% vs 21.0%, p < 0.01) compared to non-S/R. S/R had improved ORR, PFS, and OS on ICI vs. non-ICI (Table). Conclusions: S/R RCC tumors have distinctive molecular features that may account for their association with poor prognosis and outcomes on ICI.[Table: see text]

740 Background: Metastatic vRCC are aggressive tumors with poor prognosis. Our phase 2 trial of AB in vRCC showed a response rate of 33%. We investigated on-therapy changes in circulating immune cells and cytokines and their association with outcomes. Methods: Blood was collected at baseline (C1D1) and on-therapy (C3D1). Peripheral blood mononuclear cells were analyzed for cell type, expression of immune checkpoints, markers of activation, proliferation and function using flow cytometry; circulating cytokines by multiplex immunoassay. Relationship with progression-free (PFS) and overall survival (OS) was assessed by cox regression models. Results: Baseline and on-therapy samples were collected from all 60 patients. High baseline levels of immunosuppressive cytokines IL1α, IL6, CCL4 and IL13, as well as high baseline levels of CD4+ lymphocytes expressing CD69, were associated with inferior PFS and OS (Table). However, a decline in these markers on-therapy was not predictive of outcomes. On-therapy assessments showed an increase in the IFN-γ inducible cytokine CXCL10 (p

Background An elevated Neutrophil-to-lymphocyte ratio (NLR) is associated with worse outcomes in several malignancies. However, its role with contemporary immune checkpoint blockade (ICB) is unknown. We investigated the utility of NLR in metastatic renal cell carcinoma (mRCC) patients treated with PD-1/PD-L1 ICB. Methods We examined NLR at baseline and 6 (±2) weeks later in 142 patients treated between 2009 and 2017 at Dana-Farber Cancer Institute (Boston, USA). Landmark analysis at 6 weeks was conducted to explore the prognostic value of relative NLR change on overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Cox and logistic regression models allowed for adjustment of line of therapy, number of IMDC risk factors, histology and baseline NLR. Results Median follow up was 16.6 months (range: 0.7–67.8). Median duration on therapy was 5.1 months (

Background Monoclonal antibodies targeting the PD-1/PD-L1 axis have gained increasing attention across many solid tumors and hematologic malignancies due to their efficacy and favorable toxicity profile. With more than 1 agent now FDA-approved in a wide variety of tumor types, and with others in clinical trials, it is becoming more common that patients present to clinic for potential treatment with a second PD-1/PD-L1 inhibitor. Case presentation In this report, we present two patients with renal cell carcinoma and one with melanoma who received PD-1/PD-L1 inhibitors. Upon progression on their first-line PD-1/PD-L1 inhibitors, these patients received a different PD-1 inhibitor (nivolumab in all cases) and all had progressive disease as their best response to the subsequent PD-1 inhibitor. The reported clinical information focuses on the course of the disease and the responses to all treatment regimens. Conclusions Clinicians should refrain from using multiple PD-1/PD-L1 inhibitors sequentially outside of clinical trials until there is sufficient data to support this practice routinely. Prospective studies that allow prior treatment with PD-1/PD-L1 are needed to validate the efficacy and safety of these drugs in the second line or later setting. Furthermore, ongoing efforts that aim to identify mechanisms of resistance to immunotherapy will be informative and may ultimately assist physicians in select the optimal treatment following progression on PD-1/PD-L1 inhibitor.

4583 Background: NccRCC and ccRCCsd are aggressive tumors associated with poor prognosis and response to therapy. Combination strategies co-targeting VEGF signaling and inhibitory immune checkpoints are highly active in clear-cell renal cell carcinoma, but data is lacking in NccRCC and ccRCCsd. We conducted a multicenter, open-label, single arm phase II trial of atezolizumab plus bevacizumab in NccRCC and ccRCCsd. Methods: Patients with NccRCC and ccRCCsd ( > 20% sarcomatoid differentiation), and ECOG performance status of 0-2 were eligible. Prior systemic treatment was allowed with the exception of prior PD-1/PD-L1-directed therapy. Atezolizumab 1200mg and bevacizumab 15mg/kg were administered every 3 weeks until progression, unacceptable toxicity, or patient withdrawal. Primary endpoint was objective response rate (ORR) per RECIST 1.1. Exploratory biomarker analyses included PD-L1 expression on tumor (TC) and immune cells (IC), and spatial analysis of the immune infiltrate. Results: Sixty patients received at least 1 cycle of treatment, among whom 56 were evaluable for response (17 ccRCCsd and 39 NccRCC). ORR was 34% in the overall population, 53% in ccRCCsd and 26% in NccRCC. Median progression-free survival was 8.4 months (95%CI, 6.9-16.5). Baseline tumor tissue was available for 36 patients. TC PD-L1 expression ≥1% was associated with improved ORR (9/14, 64%) compared to patients with PD-L1 expression < 1% (4/20, 20%). Patients with TC PD-L1 expression ≥1% who experienced progressive disease as best response had shorter average distance between tumor cells and nearest neighboring immune cells at baseline. Further analysis of the immune tumor microenvironment on an expanded cohort, including IC PD-L1 expression and correlation with clinical outcomes, is ongoing and will be updated. Conclusions: The combination of atezolizumab plus bevacizumab is active in NccRCC and ccRCCsd. Candidate predictive biomarkers include PD-L1 expression in TC and topological analysis of the immune infiltrate. Clinical trial information: NCT02724878.

4582 Background: CD73 or ecto-5'-nucleotidase mediates the de-phosphorylation of adenosine monophosphate to adenosine which promotes immunosuppression in the tumor microenvironment. Its prognostic significance in localized RCC has not been well characterized. Methods: We assessed CD73 protein expression using immunohistochemistry (Cell Signaling Technology, D7F9A, 1:25) on tissue microarrays (TMAs) containing tumor tissue from patients with pT1-4,N0-1, M0 RCC who underwent nephrectomy.CD73 expression was quantified using a combined score (CS: intensity x percentage of cells staining positive). CD73 positivity was defined as any CD73 expression on tumor cells (CS > 0). Patients were categorized into CD73 negative (CS = 0), low ( < median CS) and high (≥ median CS) groups. Clinical data was collected retrospectively.Baseline patient characteristics were compared between CD73 negative and positive (high + low) groups using the Cochran-Armitage trend test. Multivariable Cox regression evaluated associations of CD73 expression with disease-free and overall survival (DFS, OS) after adjusting for other baseline prognostic variables. Results: Of the 112 patients included, clear cell was the most common histology (70%) followed by chromophobe (12.5%), and papillary (12%) RCC. CD73 expression (CS > 0) was noted in 22% (n = 25) of tumors and was associated with more advanced stage (T3-4/N+: 37.5% vs. 25%; p = 0.02) and a trend towards higher nuclear grade (≥3: 48% vs. 35%; p = 0.07). Median follow-up from nephrectomy was 9.7 yrs. In multivariable analysis adjusting for nuclear grade ( < 3 vs. ≥3) and stage (T1-2, N0 vs. T3-4/N+), tumors with high CD73 expression had significantly worse DFS and OS (Table). Conclusions: CD73 expression was found in 22% of RCC patients and was associated with adverse pathologic features and poor prognosis independent of tumor stage and histologic grade. Our results provide strong rationale for further investigation of the CD73/adenosine pathway as a therapeutic target in RCC. [Table: see text]

4514 Background: S/R mRCC are poorly characterized rapidly progressing tumors associated with poor prognosis. Although conventional therapies are less effective for these tumors, emerging data suggests that ICIs may be especially effective. Our aim was to characterize the genomic alterations (GA) in S/R mRCC tumors and evaluate their response to ICIs. Methods: We retrospectively compared the activity of first-line ICIs to non-ICI-based therapies for S/R mRCC patients (pts) treated at DFCI and analyzed sequencing data from an NGS panel (275-447 genes) on a subset of these patients (matched by histology to non-S/R mRCC). For S/R mRCC pts treated with ICI vs non-ICI therapies, overall survival (OS) and time to treatment failure (TTF) were compared by Cox regression and objective response rate (ORR) by logistic regression. GA frequencies were compared by Fisher’s test and tumor mutational burden (TMB) by Mann Whitney U between S/R and non-S/R mRCC. Results were considered statistically significant if p < 0.05 or q < 0.10. Results: 125 S/R mRCC pts were included (88 S, 23 R, 14 S&R) among which 103 were clear cell and 48 had sequencing data. GA in BAP1 were significantly more frequent in S/R vs non-S/R (25% vs 4.3%; q = 0.096) while other GA had similar frequencies and TMB (median [IQR]) was similar (7.2 [5.2-8.4] vs 6.8 [5.3-9.1] mut/Mb; p = 0.98). Median follow-up was 35.4 (95% CI = 24.9 – 46.0) months (m). On multivariable analysis, S/R mRCC pts treated with ICI had significantly better clinical outcomes (Table). Conclusions: Pts with S/R mRCC have a higher frequency of BAP1 GA and better outcomes on ICIs compared to non-ICI-based therapies. Future studies should determine the molecular mechanisms underlying the improved response to ICIs in S/R mRCC. [Table: see text]

103 Background: ICIs have shown benefit across several metastatic carcinomas, yet predictive biomarkers are still lacking. 20% of malignancies harbor alterations in ≥1gene that is part of PBAF complex. With recent data suggesting an association between PBRM1 mutations (mts) and outcomes in renal cell carcinoma (RCC) pts treated with ICIs (Miao, Science, 2018), we examined the association between PBAF mts and OS in ICI-treated patients across several solid cancer (ca) types. Methods: Of 6007 pts with different ca histologies and targeted exome sequencing (Oncopanel) at Dana Farber Cancer institute (DFCI), 138 pts had truncating mts in any PBAF gene (SMARCA4, PBRM1, and ARID2) or oncogenic missense mts in SMARCA4 and were treated with ICIs. 138 histology-matched DFCI pts had none. A publicly-available cohort (2:1 histology matched) from Memorial Sloan Kettering (MSKCC) (Samstein et al., Nature Genetics, 2019) of 621 ca pts (PBAF mutant [MT] = 207, PBAF wild type [WT] = 414) treated with ICIs was analyzed for association between PBAF mts and OS. OS was defined from time from ICI initiation. OS was compared by Cox regression between PBAF MT and PBAF WT. Hazard ratio (HR) was derived using univariable and multivariable analysis (MVA) adjusted for ICI regimen (single vs combination) and age. Results: Median (Md) follow-up for the combined cohort (n = 897) was 27 months (m). Major histologies were non-small cell lung ca (268; 29.9%), melanoma (220; 24.5%), RCC (181; 20.2%), and bladder ca (65; 7.2%). Results on univariable and MVA analyses from individual and combined cohorts are presented below. Conclusions: PBAF mts are associated with survival in ICI-treated ca pts. Work in progress with non-ICI treated pts will determine if this is prognostic or predictive of response. [Table: see text]

66 Background: Patients with mRCC with S/R components tend to have a poor prognosis with few therapeutic options available. Recent data suggest that immune checkpoint inhibitor (ICI)-based therapies may be especially effective for these patients. Our aim was to evaluate the efficacy of ICI-based therapies in patients with S/R mRCC. Methods: We retrospectively assessed objective response rate (ORR), progression free survival (PFS) & overall survival (OS) of patients with S/R mRCC treated at our institution with first-line ICI-based therapies and compared these to those of patients treated with first-line non-ICI-based therapies. Univariable and multivariable (adjusted for IMDC group) Cox and logistic regressions were performed. Results: 92 patients (70 S, 9 R, and 13 S&R) patients were included, of which 74 with a clear-cell component. For all patients (regardless of therapy), 74 (80.4%) patients experienced a PFS event (progression or death) and 52 (56.5%) died at 25.3 months (m) median follow-up. Overall median PFS was 5.3 m (95% CI= 3.4–7.2) and 24 m OS rate was 39.5% (27.4–51.7). Out of 78 patients in whom response was evaluable, ORR was 30.8% (20.4–41.2). Patients treated with ICI-based therapies had significantly better ORR, PFS, and OS on multivariable analysis (table). Conclusions: mRCC patients with S/R components have significantly better ORR, PFS, and OS with first-line ICI-based compared to non-ICI-based therapies. These data support the use of ICI-based therapies for patients with S/R mRCC. [Table: see text]

548 Background: NccRCC and sccRCC have historically been underrepresented in clinical trials. Even with targeted therapy, most patients have inferior survival compared to clear cell renal cell carcinoma. The combination of atezolizumab and bevacizumab has demonstrated safety and efficacy in ccRCC. In this multicenter, phase II, open-label, single arm trial we evaluate the efficacy of atezolizumab and bevacizumab in patients with nccRCC and sccRCC with >20% sarcomatoid differentiation. Methods: Eligible patients had an ECOG performance status of 0-2 and may have received prior therapy. Prior PD-1/PD-L1 therapy was not allowed. Patients underwent a mandatory baseline biopsy and subsequently received atezolizumab 120 mg and bevacizumab 15 mg/kg intravenously every 3 weeks. Patients remained on therapy until radiographic progression, unacceptable adverse events, or withdrawal. The primary end point was overall response rate (ORR) as determined by RECIST version 1.1. Results: 65 patients were enrolled of whom 52 had ≥1 response assessment and were included in this analysis. 36 patients had nccRCC (papillary n=14, chromophobe n=8, unclassified RCC n=3, collecting duct n=3, translocation n=3, other n=5), and 16 patients had sccRCC. 17 patients received prior systemic therapy, 16 of whom had nccRCC. The ORR was 31% in the overall cohort (Table 1). 10 patients (19%) developed grade 3 treatment-related adverse events (AEs), half of which were immune-related. There were no grade 4-5 AEs. Conclusions: In this study, we show that therapy with atezolizumab and bevacizumab was safe and demonstrated anti-tumor activity in nccRCC and sccRCC. Further analyses will report ORR by histologic subtype and PD-L1 expression status. Analysis of tissue and blood-based biomarkers of response are ongoing. Clinical trial information: NCT02724878. [Table: see text]