Geospatial characterization of immune cell distributions and dynamics across the microenvironment in clear cell renal cell carcinoma.

INTRODUCTION: In clear cell renal cell carcinoma (ccRCC), tumor-associated macrophage (TAM) induction of CD8+T cells into a terminally exhausted state has been implicated as a major mechanism of immunotherapy resistance, but a deeper biological understanding is necessary. METHODS: Primary ccRCC tumor samples were obtained from 97 patients between 2004 and 2018. Multiplex immunofluorescence using lymphoid and myeloid markers was performed in seven regions of interest per patient across three predefined zones, and geospatial analysis was performed using Ripley's K analysis, a methodology adapted from ecology. RESULTS: Clustering of CD163+M2 like TAMs into the stromal compartment at the tumor-stroma interface was associated with worse clinical stage (tumor/CD163+nK(75): stage I/II: 4.4 (IQR -0.5 to 5.1); stage III: 1.4 (IQR -0.3 to 3.5); stage IV: 0.6 (IQR -2.1 to 2.1); p=0.04 between stage I/II and stage IV), and worse overall survival (OS) and cancer-specific survival (CSS) (tumor/CD163+nK(75): median OS-hi=149 months, lo=86 months, false-discovery rate (FDR)-adj. Cox p<0.001; median CSS-hi=174 months, lo=85 months; FDR-adj. Cox p<0.001). An RNA-seq differential gene expression score was developed using this geospatial metric, and was externally validated in multiple independent cohorts of patients with ccRCC including: TCGA KIRC, and the IMmotion151, IMmotion150, and JAVELIN Renal 101 clinical trials. In addition, this CD163+ geospatial pattern was found to be associated with a higher TIM-3+ proportion of CD8+T cells, indicative of terminal exhaustion (tumor-core: 0.07 (IQR 0.04-0.14) vs 0.40 (IQR 0.15-0.66), p=0.05). CONCLUSIONS: Geospatial clustering of CD163+M2 like TAMs into the stromal compartment at the tumor-stromal interface was associated with poor clinical outcomes and CD8+T cell terminal exhaustion.

Advances in Imaging-Based Biomarkers in Renal Cell Carcinoma: A Critical Analysis of the Current Literature.

Cross-sectional imaging is the standard diagnostic tool to determine underlying biology in renal masses, which is crucial for subsequent treatment. Currently, standard CT imaging is limited in its ability to differentiate benign from malignant disease. Therefore, various modalities have been investigated to identify imaging-based parameters to improve the noninvasive diagnosis of renal masses and renal cell carcinoma (RCC) subtypes. MRI was reported to predict grading of RCC and to identify RCC subtypes, and has been shown in a small cohort to predict the response to targeted therapy. Dynamic imaging is promising for the staging and diagnosis of RCC. PET/CT radiotracers, such as 18F-fluorodeoxyglucose (FDG), 124I-cG250, radiolabeled prostate-specific membrane antigen (PSMA), and 11C-acetate, have been reported to improve the identification of histology, grading, detection of metastasis, and assessment of response to systemic therapy, and to predict oncological outcomes. Moreover, 99Tc-sestamibi and SPECT scans have shown promising results in distinguishing low-grade RCC from benign lesions. Radiomics has been used to further characterize renal masses based on semantic and textural analyses. In preliminary studies, integrated machine learning algorithms using radiomics proved to be more accurate in distinguishing benign from malignant renal masses compared to radiologists' interpretations. Radiomics and radiogenomics are used to complement risk classification models to predict oncological outcomes. Imaging-based biomarkers hold strong potential in RCC, but require standardization and external validation before integration into clinical routines.

Systemic Immunological Determinants of Oncological Outcomes After Surgery for Localized Renal Cell Carcinoma.

INTRODUCTION & OBJECTIVES: In systemic therapy trials, a decreasing neutrophil-to-lymphocyte ratio (NLR) after treatment for metastatic renal cell carcinoma (RCC) has been associated with improved oncologic outcomes. Paradoxically, for patients with localized RCC treated with upfront surgery the opposite effect has been reported. We thus aimed to evaluate NLR dynamics on localized RCC recurrence. MATERIALS AND METHODS: Treatment naïve patients with localized RCC managed surgically between 2005 and 2020 were included. Preoperative NLR was calculated within 6-weeks prior to surgery and postoperative NLR was calculated between 4 and twelve-weeks after surgery. Patients were followed for disease recurrence, noting metastatic sites and postoperative infections. Cox regression were used to determine whether the relative change in postoperative NLR was associated with metastasis-free survival (MFS) and cancer-specific survival (CSS), adjusted for preoperative NLR. RESULTS: In the cohort of 3310 patients, 996 (30%) had postoperative NLR available. These patients generally had more advanced disease, with 100 developing metastases and 38 dying from kidney cancer. Median MFS follow-up was 4.4 years. Decreasing 2-month postoperative NLR was associated with non-statistically significant worse MFS and CSS (HR 0.79, 95% 0.50, 1.24, P = .3; HR 0.83, 95% C.I. 0.40, 1.73; P = .6). On sensitivity analysis, across all NLR measurements, with NLR as a time-dependent covariate, results were similar, with a declining NLR associated with adverse MFS (HR 0.85, 95% CI 0.69, 1.30, P-value = .10), though not meeting conventional levels of significance. CONCLUSION: In higher-risk localized RCC patients, postoperative NLR is not suitable as a biomarker for predicting recurrences.

A Decade of Robotic-Assisted Radical Nephrectomy with Inferior Vena Cava Thrombectomy: A Systematic Review and Meta-Analysis of Perioperative Outcomes.

PURPOSE: Open radical nephrectomy with inferior vena cava thrombectomy (O-CT) is standard management for renal cell carcinoma with inferior vena cava thrombus. First reported a decade ago, robotic-assisted radical nephrectomy with inferior vena cava thrombectomy (R-CT) is a minimally invasive option for this disease. We aimed to perform a systematic review to assess the safety and feasibility of R-CT in terms of perioperative outcomes and compare the outcomes between R-CT and O-CT. MATERIALS AND METHODS: The PubMed®, Scopus®, Cochrane Central Register of Controlled Trials and Web of ScienceTM databases were searched using the free-text and MeSH terms "renal cell carcinoma," "inferior vena cava," "thrombosis" or "thrombus," "robot" and "thrombectomy." Studies reporting perioperative outcomes of R-CT and studies comparing R-CT with O-CT were included. The review was done in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. RESULTS: The search retrieved 28 articles describing R-CT, including 7 comparative studies. This systematic review included 1,375 patients, out of which 329 patients were in single-arm studies and 1,046 patients were in comparative studies. Of the 329 patients who underwent R-CT, 14.7% were level I, 60.9% level II, 20.4% level III and 2.5% level IV thrombus. Operative time ranged from 150 to 530 minutes; blood transfusion was administered in 38.2% (126). The overall complication rate was 30.3% (99). R-CT, in comparison to O-CT, was associated with a lower blood transfusion rate (18.4% vs 64.3%, p=0.002) and a lower complication rate (14.5% vs 36.7%, p=0.005). Major complication and 30-day mortality rates were similar in both groups. CONCLUSIONS: R-CT has acceptable perioperative outcomes in carefully selected patients. Compared with O-CT, R-CT is associated with a lower blood transfusion rate and fewer overall complications. In experienced hands with carefully selected patients, R-CT is feasible and safe, with acceptable outcomes; however, selection bias limits definitive inference of these results, and optimal patient selection criteria remain to be described.

Differences in risk factors for molecular subtypes of clear cell renal cell carcinoma.

The ccA and ccB molecular subtypes of clear cell renal cell carcinoma (ccRCC) have well-characterized prognostic relevance. However, it is not known whether they possess distinct etiologies. We investigated the relationships between these subtypes and RCC risk factors within a case-control study conducted in Eastern Europe. We analyzed risk factor data for ccA (n = 144) and ccB (n = 106) cases and 1476 controls through case-only and case-control comparisons to assess risk factor differences across subtypes using logistic and polytomous regression models. We also performed a meta-analysis summarizing case-only results from our study and three patient cohorts. Patients with ccB tumors had poorer survival than those with ccA tumors and were more likely to be male (case-only odds ratio [OR] 2.68, 95% confidence interval [CI] 1.43-5.03). In case-control analyses, body mass index was significantly associated with ccA tumors (OR 2.45, 95% CI 1.18-5.10 for ≥35 vs <25 kg/m2 ) but not with ccB tumors (1.52, 0.56-4.12), while trichloroethylene was associated with ccB but not ccA (OR 3.09, 95% CI 1.11-8.65 and 1.25, 0.36-4.39 respectively for ≥1.58 ppm-years vs unexposed). A polygenic risk score of genetic variants identified from genome-wide association studies was associated with both ccA and, in particular, ccB (OR 1.82, 1.11-2.99 and 2.87, 95% CI 1.64-5.01 respectively for 90th vs 10th percentile). In a meta-analysis of case-only results including three patient cohorts, we still observed the ccB excess for male sex and the ccA excess for obesity. In conclusion, our findings suggest the existence of etiologic heterogeneity across ccRCC molecular subtypes for several risk factors.

TFEB Expression Profiling in Renal Cell Carcinomas: Clinicopathologic Correlations.

TFEB is overexpressed in TFEB-rearranged renal cell carcinomas as well as in renal tumors with amplifications of TFEB at 6p21.1. As recent literature suggests that renal tumors with 6p21.1 amplification behave more aggressively than those with rearrangements of TFEB, we compared relative TFEB gene expression in these tumors. This study included 37 TFEB-altered tumors: 15 6p21.1-amplified and 22 TFEB-rearranged (including 5 cases from The Cancer Genome Atlas data set). TFEB status was verified using a combination of fluorescent in situ hybridization (n=27) or comprehensive molecular profiling (n=13) and digital droplet polymerase chain reaction was used to quantify TFEB mRNA expression in 6p21.1-amplified (n=9) and TFEB-rearranged renal tumors (n=19). These results were correlated with TFEB immunohistochemistry. TFEB-altered tumors had higher TFEB expression when normalized to B2M (mean: 168.9%, n=28), compared with non-TFEB-altered controls (mean: 7%, n=18, P=0.005). Interestingly, TFEB expression in tumors with rearrangements (mean: 224.7%, n=19) was higher compared with 6p21.1-amplified tumors (mean: 51.2%, n=9; P=0.06). Of note, classic biphasic morphology was only seen in TFEB-rearranged tumors and when present correlated with 6.8-fold higher TFEB expression (P=0.00004). Our results suggest that 6p21.1 amplified renal tumors show increased TFEB gene expression but not as much as t(6;11) renal tumors. These findings correlate with the less consistent/diffuse expression of downstream markers of TFEB activation (cathepsin K, melan A, HMB45) seen in the amplified neoplasms. This suggests that the aggressive biological behavior of 6p21.1 amplified renal tumors might be secondary to other genes at the 6p21.1 locus that are co-amplified, such as VEGFA and CCND3, or other genetic alterations.

Characterization and Impact of TERT Promoter Region Mutations on Clinical Outcome in Renal Cell Carcinoma.

BACKGROUND: Mutations in the promoter region of the TERT gene have been detected in a variety of cancers. These mutations can potentially lead to unlimited cell divisions and result in poor clinical prognosis. OBJECTIVE: To determine the role and relevance of TERT promoter region mutations in both clear cell (ccRCC) and non-clear cell (nccRCC) renal cell carcinoma using ultra-deep and whole-genome sequencing methods on primary tumor samples. DESIGN, SETTING, AND PARTICIPANTS: DNA from 281 kidney tumors (147 ccRCC and 134 nccRCC) was sequenced between 2013 and 2015, and clinical outcomes for these patients from a single institution were retrospectively analyzed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Differences in patient characteristics and mutational status were tested using Fisher's exact test for categorical variables and the Wilcoxon rank sum test for continuous variables. Survival times were estimated using the Kaplan-Meier method and differences were tested using the log-rank test. RESULTS AND LIMITATIONS: TERT mutations occurred in 12.2% of ccRCC and 10.4% of nccRCC cases. In >80% of the cases, mutations were located at C228T and were found to co-occur only rarely with other relevant RCC driver genes. The median follow-up among survivors overall was 2.5 yr (range 0.1-18.3). TERT promoter mutations were significantly associated with cancer-specific survival in ccRCC (hazard ratio 2.68, 95% confidence interval 1.19-6.01; p=0.013). In nccRCC, TERT mutations were significantly associated with larger tumors and metastatic development. Assessment of further relevant clinical associations was precluded in the nccRCC group by the heterogeneous and small sample size. CONCLUSIONS: Our data suggests that TERT mutational status reflects a distinct pathogenesis with an aggressive disease course in RCC. Stratifying patients with this unique tumorigenesis that leads to poor clinical outcomes could be a putative target for novel therapeutics. PATIENT SUMMARY: We show a previously unrecognized frequency of TERT promoter mutations in both clear cell and non-clear cell renal cell carcinoma. TERT promoter mutations were associated with some worse outcomes in patients with clear cell renal cell carcinoma.

Rejection of immunogenic tumor clones is limited by clonal fraction.

Tumors often co-exist with T cells that recognize somatically mutated peptides presented by cancer cells on major histocompatibility complex I (MHC-I). However, it is unknown why the immune system fails to eliminate immune-recognizable neoplasms before they manifest as frank disease. To understand the determinants of MHC-I peptide immunogenicity in nascent tumors, we tested the ability of thousands of MHC-I ligands to cause tumor subclone rejection in immunocompetent mice by use of a new 'PresentER' antigen presentation platform. Surprisingly, we show that immunogenic tumor antigens do not lead to immune-mediated cell rejection when the fraction of cells bearing each antigen ('clonal fraction') is low. Moreover, the clonal fraction necessary to lead to rejection of immunogenic tumor subclones depends on the antigen. These data indicate that tumor neoantigen heterogeneity has an underappreciated impact on immune elimination of cancer cells and has implications for the design of immunotherapeutics such as cancer vaccines.

The natural history of large renal masses followed on observation.

PURPOSE: The safety and feasibility of active surveillance in comorbid patients with renal masses ≥4.0cm is uncertain. The aim of this study is to describe our institutional experience with the observation of large renal masses. MATERIALS AND METHODS: One hundred patients were identified with renal masses ≥ 4.0cm that were followed on observation for at least 6 months without surgical intervention between 1994 and 2016. Linear regression was conducted to determine predictors for renal mass growth and competing risk methods were used to estimate the probability of progression in the setting of death from other causes. RESULTS: Median age at diagnosis was 73 years and 73% of patients had a Charlson Comorbidity index ≥ 4. At presentation, the median mass size was 4.9cm. The median growth rate was 0.4cm/y and there were no significant predictors of growth. Surveillance was discontinued in 34 patients who underwent delayed intervention. Median follow up for metastasis-free survivors was 4 years. In total, 10 patients developed metastatic disease, 3 died from kidney cancer and 30 patients died from other causes. The 5-year probability of other cause mortality was 22% (95% CI: 14%-32%) compared to 6% (95% CI: 2%-13%) for metastatic progression of kidney cancer. CONCLUSION: In highly comorbid patients, the observation of large renal masses has low likelihood for metastatic progression relative to the risk of nonkidney cancer related death. This data supports the use of surveillance as an acceptable strategy for highly selected patients with competing risks from other serious illnesses.

Genomic alterations as predictors of survival among patients within a combined cohort with clear cell renal cell carcinoma undergoing cytoreductive nephrectomy.

PURPOSE: To establish prognostic genomic biomarkers for patients with metastatic clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: We identified 60 patients who presented with metastatic ccRCC at our institution between 2001 and 2015 and had genomic sequencing on their primary tumor. We pooled these patients with 107 other patients with the same inclusion criteria from three well-known public databases. Five commonly mutated genes were chosen for analysis: VHL, PBRM1, BAP1, SETD2, and KDM5C. Overall survival (OS) was estimated using the Kaplan-Meier method and the log-rank test was used for comparisons between groups. RESULTS: Median OS in the cohort was 2.5 years. Higher Fuhrman grade was associated with decreased median OS (P<0.001). Mutations in SETD2 (P = 0.027) and KDM5C (P = 0.019) were associated with reduced risk of death (hazard ratio [HR] = 0.58 [95% CI: 0.35-0.94] and HR = 0.43 [95% CI: 0.22-0.85], respectively). BAP1 mutations (P = 0.008) were associated with increased risk of death (HR = 1.81 [95% CI: 1.16-2.83]). There were significantly more female patients with a BAP1 mutation than females in the overall cohort (P = 0.001). CONCLUSIONS: Mutations in BAP1 negatively affected OS, whereas SETD2 and KDM5C mutations were associated with prolonged OS in our pooled cohort of 167 patients with metastatic ccRCC. Our results expand upon efforts at understanding genomic biomarkers in localized disease. Those efforts set the stage for our novel investigation examining associations of select recurrent somatic mutations in stage IV patients with ccRCC.

The difficulty in selecting patients for cytoreductive nephrectomy: An evaluation of previously described predictive models.

PURPOSE: To externally evaluate a preoperative points system and a preoperative nomogram, both created to assess time to death after cytoreductive nephrectomy (CN). MATERIALS AND METHODS: We identified 298 patients who underwent CN at our institution, a tertiary cancer center, between 1989 and 2015. To validate the points system, we compared reported overall survival (OS) for each criterion to observed OS in our cohort. To evaluate the nomogram, we prognosticated risk of death at 6 months after surgery for 280 patients with sufficient follow-up in our cohort and evaluated discrimination using area under the curve (AUC) and calibration. Decision curve analysis was performed to assess clinical utility of the nomogram. RESULTS: Significant differences in OS were observed between patients with and without 5 of 7 criteria on univariate analysis: low albumin (P<0.0001), high lactate dehydrogenase (P = 0.002), liver metastasis (P = 0.004), retroperitoneal lymphadenopathy (P = 0.002), and supradiaphragmatic lymphadenopathy (P = 0.019). Discrimination from the preoperative model, predicting death within 6 months of surgery was lower in our cohort (AUC = 0.65, 95% CI: 0.52-0.79) than the original publication (AUC = 0.76). Decision curve analysis demonstrated little benefit for applicability. CONCLUSIONS: Five previously defined risk factors are predictive of decreased OS after CN in our cohort. We found lower discrimination using the preoperative model and minimal clinical utility according to decision analysis in our study cohort. These findings suggest the need for improved models to aid patient stratification and consequent treatment choice.

Molecular profiling of renal cell carcinoma: building a bridge toward clinical impact.

PURPOSE OF REVIEW: The daunting task of identifying key molecular drivers of renal cell carcinoma (RCC) has begun to reveal significant insights into tumor biology. This review provides an update on recent discoveries in this field and their possible clinical implications. RECENT FINDINGS: Molecular profiles within the classic RCC histologic subtypes present distinctive appreciation of tumor biology and also allow for exploitation of targeted treatment regimens for patients with metastatic disease. Prognostic signatures have demonstrated the ability to accurately predict many clinical outcomes. SUMMARY: The molecular and genomic profiling of RCC subtypes has identified a unique and diverse spectrum of alterations. Utilization of these characteristics to improve our prognostic and therapeutic outcomes in the clinical realm remains in its infancy but is rapidly advancing.

The effect of delaying nephrectomy on oncologic outcomes in patients with renal tumors greater than 4cm.

OBJECTIVES: Delaying nephrectomy<3 months does not adversely affect treatment outcome of renal tumors. Whether surgical waiting time (SWT; time from diagnosis to surgery)>3 months affects treatment outcome for large renal masses has not been well studied. We aimed to evaluate if SWT is associated with treatment outcome of renal masses >4cm and identify patients who are more likely to experience prolonged SWT. MATERIALS AND METHODS: Data from 1,484 patients undergoing radical or partial nephrectomy at a single institution for a nonmetastatic renal mass>4cm between 1995 and 2013 were reviewed. Patients with benign tumors and incomplete preoperative data were excluded. The association between SWT and disease upstaging at the time of surgery and recurrence at 2 and 5 years was assessed using logistic regression. Cancer-specific survival (CSS) and overall survival were assessed with landmark survival analyses and multivariable Cox proportional hazards models. All analyses were adjusted for patient and tumor characteristics. RESULTS: Of the final cohort of 1,278 patients, 267 (21%) had SWT>3 months. Patients with larger, symptomatic tumors had shorter SWT. Median follow-up for survivors was 3.8 years (interquartile range: 1.5-7.4). On multivariable analysis, SWT was not associated with disease upstaging, recurrence, or CSS. Longer SWT was associated with decreased overall survival (hazard ratio = 1.17; 95% CI: 1.08-1.27; P = 0.0002). Sex and tumor size, histology, and presentation were associated with disease upstaging, recurrence, and CSS. The most common cause for surgical delay>3 months was evaluation and treatment of comorbidities. CONCLUSION: Patient and tumor characteristics, rather than SWT, were associated with disease upstaging, recurrence, and CSS, and should guide the decision to delay surgery when treating nonmetastatic renal tumors>4cm.

Partial and Radical Nephrectomy for Unilateral Synchronous Multifocal Renal Cortical Tumors.

OBJECTIVE: To evaluate clinicopathologic characteristics and treatment outcomes of patients undergoing partial nephrectomy (PN) or radical nephrectomy (RN) for unilateral synchronous multifocal renal tumors. METHODS: We retrospectively reviewed medical records for 128 patients with nonmetastatic, unilateral, synchronous, multifocal renal tumors who underwent surgical resection at our institution from 1995 to 2012. Five patients with hereditary renal cell carcinoma were excluded. Differences between patient and tumor characteristics from the 2 nephrectomy groups were evaluated. Outcomes in terms of recurrence-free survival, overall survival, and chronic kidney disease upstaging were estimated using Kaplan-Meier methods. The log-rank test was used for group comparisons. RESULTS: The study cohort included 78 PN patients (63%) and 45 RN patients (37%); 17 of 95 planned PN (18%) were converted to RN. Tumor diameter and RENAL nephrometry scores were greater in RN patients (P <.0001 and P = .0002, respectively). Pathologic stage T3 was seen in 40% of RN patients and 10% of PN patients (P = .0002). Histologic concordance was apparent in 60 of 123 patients (49%). Median follow-up for patients alive without a recurrence was 4 years. Five-year recurrence-free survival was 98% for PN and 85% for RN. Five-year overall survival was 96% for PN and 86% for RN (P = .5). Five-year freedom from chronic kidney disease upstaging was 74% for PN and 55% for RN (P = .11). CONCLUSION: Partial nephrectomy for the treatment of unilateral, synchronous, multifocal, renal tumors with favorable characteristics was associated with a low recurrence rate. These findings suggest PN is an appropriate management strategy for this group of carefully selected patients.