Non-clear cell renal cancer: disease-based management and opportunities for targeted therapeutic approaches

Systemic therapy for non-clear cell renal cell carcinomas: A systematic review

OBJECTIVE

Renal cell carcinoma (RCC) is the most common kidney cancer, with clear cell RCC being the predominant subtype. However, non-clear cell RCC constitutes a significant proportion of cases, presenting distinct challenges in treatment due to its varied histological subtypes. Despite recent advancements, the optimal therapeutic approach for non-clear cell RCC remains uncertain due to limited high-quality evidence. This systematic review aims to evaluate the efficacy of systemic therapies in nccRCC subgroups.

DATA SOURCE

A comprehensive literature search identified studies from 2010 to 2024, using PubMed and Clinicaltrials.gov databases focusing on clinical trials and treatment outcomes.

DATA SUMMARY

Results highlight the evolving therapeutic landscape, with targeted agents and immunotherapy demonstrating promising anti-tumor effects. Notably, tyrosine kinase inhibitors (TKIs) such as sunitinib and mTOR inhibitors like temsirolimus have shown efficacy across different subtypes. Combination therapies, including immunotherapy-based regimens, have also shown favorable outcomes. immune checkpoint inhibitors such as nivolumab and pembrolizumab demonstrated encouraging antitumor activity. Furthermore, specific targeting of signaling pathways, such as the c-MET pathway, has demonstrated efficacy in certain PapillaryRCC.

CONCLUSION

While combination therapies, including immunotherapies, have shown positive outcomes, immune checkpoint inhibitors like nivolumab and pembrolizumab have demonstrated encouraging antitumor activity. Additionally, targeting the c-MET pathway has proven effective in certain papillary RCC. Further research is warranted to establish optimal treatment strategies and improve outcomes for patients with non-clear cell RCC. Systemic therapy for non-clear cell RCC is complex and evolving. Further research is needed to delineate optimal treatment strategies for different histological subtypes and improve patient outcomes.

Racial and Ethnic Disparities in Survival Outcomes of Metastatic Renal Cell Carcinoma Patients Receiving Immunotherapy

BACKGROUND

Immune checkpoint inhibitors (ICI) have significantly improved survival outcomes of metastatic renal cell carcinoma (mRCC). However, ethnic and racial minorities are often underrepresented in ICI clinical trials, leading to limited knowledge about ICI-specific survival outcomes for mRCC across different racial and ethnic groups. We investigated the impact of race and ethnicity on the ICI-specific survival outcomes of mRCC.

MATERIALS

We used The National Cancer Database (NCDB) to retrieve the data of 4858 mRCC patients diagnosed from 2014 to 2019 and receiving ICI-based regimens. We then compared survival outcomes using the Kaplan-Meier method and the Log-rank test. We analyzed the data using univariate and multivariable Cox regression analysis, adjusted for age, sex, comorbidity index, treatment centers, and grade.

RESULTS

White and Asian patients had significantly longer median overall survival (mOS) than African American (AA) patients (23.2 [95% CI 21.6, 24.7; P = .001] and 22.2 [95% CI 16.4, 55.1; P = .047] vs. 14.8 [95% CI 11.9, 19.2] months, respectively). After adjustment, White patients had significantly longer median OS (adjusted hazard ratio [HR] 0.71 [95% CI 0.58, 0.84]; P = .001). There was no significant difference in the mOS between Hispanic and non-Hispanic patients (P = .39).

CONCLUSION

Black race is an independent predictor of ICI-related survival in mRCC patients, independent of sociodemographics, clinicopathological, and treatment-related factors. Future research is required to understand the underlying reasons for these disparities, including potential genetic or biological differences and social and environmental factors.

Exercise, cancer, and the cardiovascular system: clinical effects and mechanistic insights

Cardiovascular diseases and cancer are the leading causes of death in the Western world and share common risk factors. Reduced cardiorespiratory fitness (CRF) is a major determinant of cardiovascular morbidity and cancer survival. In this review we discuss cancer- induced disturbances of parenchymal, cellular, and mitochondrial function, which limit CRF and may be antagonized and attenuated through exercise training. We show the impact of CRF on cancer survival and its attenuating effects on cardiotoxicity of cancer-related treatment. Tailored exercise programs are not yet available for each tumor entity as several trials were performed in heterogeneous populations without adequate cardiopulmonary exercise testing (CPET) prior to exercise prescription and with a wide variation of exercise modalities. There is emerging evidence that exercise may be a crucial pillar in cancer treatment and a tool to mitigate cardiotoxic treatment effects. We discuss modalities of aerobic exercise and resistance training and their potential to improve CRF in cancer patients and provide an example of a periodization model for exercise training in cancer.

Machine Learning-Based Magnetic Resonance Radiomics Analysis for Predicting Low- and High-Grade Clear Cell Renal Cell Carcinoma

PURPOSE

To explore whether high- and low-grade clear cell renal cell carcinomas (ccRCC) can be distinguished using radiomics features extracted from magnetic resonance imaging.

METHODS

In this retrospective study, 154 patients with pathologically proven clear ccRCC underwent contrast-enhanced 3 T magnetic resonance imaging and were assigned to the development (n = 122) and test (n = 32) cohorts in a temporal-split setup. A total of 834 radiomics features were extracted from whole-tumor volumes using 3 sequences: T2-weighted imaging (T2WI), diffusion-weighted imaging, and contrast-enhanced T1-weighted imaging. A random forest regressor was used to extract important radiomics features that were subsequently used for model development using the random forest algorithm. Tumor size, apparent diffusion coefficient value, and percentage of tumor-to-renal parenchymal signal intensity drop in the tumors were recorded by 2 radiologists for quantitative analysis. The area under the receiver operating characteristic curve (AUC) was generated to predict ccRCC grade.

RESULTS

In the development cohort, the T2WI-based radiomics model demonstrated the highest performance (AUC, 0.82). The T2WI-based radiomics and radiologic feature hybrid model showed AUCs of 0.79 and 0.83, respectively. In the test cohort, the T2WI-based radiomics model achieved an AUC of 0.82. The range of AUCs of the hybrid model of T2WI-based radiomics and radiologic features was 0.73 to 0.80.

CONCLUSION

Magnetic resonance imaging-based classifier models using radiomics features and machine learning showed satisfactory diagnostic performance in distinguishing between high- and low-grade ccRCC, thereby serving as a helpful noninvasive tool for predicting ccRCC grade.

Associations of Renal Cell Carcinoma Subtype with Patient Demographics, Comorbidities, and Neighborhood Socioeconomic Status in the California Population

BACKGROUND

Renal cell carcinoma (RCC) subtypes differ in molecular characteristics and prognosis. We investigated the associations of RCC subtype with patient demographics, comorbidity, and neighborhood socioeconomic status (nSES).

METHODS

Using linked California Cancer Registry and Office of Statewide Health Planning and Development data, we identified history of hypertension, diabetes, and kidney disease prior to RCC diagnosis in Asian/Pacific Islander, non-Latino Black, Latino, and non-Latino White adults diagnosed with their first pathologically confirmed RCC from 2005 through 2015. We used multinomial multivariable logistic regression to model the association of demographics, comorbidity, and nSES with clear-cell, papillary, and chromophobe RCC subtype.

RESULTS

Of the 40,016 RCC cases included, 62.6% were clear cell, 10.9% papillary, and 5.9% chromophobe. The distribution of subtypes differed strikingly by race and ethnicity, ranging from 40.4% clear cell and 30.4% papillary in non-Latino Black adults to 70.7% clear cell and 4.5% papillary in Latino adults. In multivariable analysis, non-Latino Black individuals had a higher likelihood of presenting with papillary (OR, 3.99; 95% confidence interval, 3.61-4.42) and chromophobe (OR, 1.81; 1.54-2.13) versus clear-cell subtype compared with non-Latino White individuals. Both hypertension (OR, 1.19; 1.10-1.29) and kidney disease (OR, 2.38; 2.04-2.77 end-stage disease; OR, 1.52; 1.33-1.72 non-end-stage disease) were associated with papillary subtype. Diabetes was inversely associated with both papillary (OR, 0.63; 0.58-0.69) and chromophobe (OR, 0.61; 0.54-0.70) subtypes.

CONCLUSIONS

RCC subtype is independently associated with patient demographics, and comorbidity.

IMPACT

Targeted RCC treatments or RCC prevention efforts may have differential impact across population subgroups.

Heterogeneity of tumor microenvironment is associated with clinical prognosis of non-clear cell renal cell carcinoma: a single-cell genomics study

Non-clear renal cell carcinomas (nccRCCs) are less frequent in kidney cancer with histopathological heterogeneity. A better understanding of the tumor biology of nccRCC can provide more effective treatment paradigms for different subtypes. To reveal the heterogeneity of tumor microenvironment (TME) in nccRCC, we performed 10x sing-cell genomics on tumor and normal tissues from patients with papillary renal cell carcinoma (pRCC), chromophobe RCC (chrRCC), collecting duct carcinoma (CDRCC) and sarcomatoid RCC (sarRCC). 15 tissue samples were finally included. 34561 cells were identified as 16 major cell clusters with 34 cell subtypes. Our study presented the sing-cell landscape for four types of nccRCC, and demonstrated that CD8+ T cells exhaustion, tumor-associated macrophages (TAMs) and sarcomatoid process were the pivotal factors in immunosuppression of nccRCC tissues and were closely correlated with poor prognosis. Abnormal metabolic patterns were present in both cancer cells and tumor-infiltrating stromal cells, such as fibroblasts and endothelial cells. Combined with CIBERSORTx tool, the expression data of bulk RNA-seq from TCGA were labeled with cell types of our sing-cell data. Calculation of the relative abundance of cell types revealed that greater proportion of exhausted CD8+ T cells, TAMs and sarRCC derived cells were correlated with poor prognosis in the cohort of 274 nccRCC patients. To the best of our knowledge, this is the first study that provides a more comprehensive sight about the heterogeneity and tumor biology of nccRCC, which may potentially facilitate the development of more effective therapies for nccRCC.

Nivolumab in metastatic renal cell carcinoma: results from the Turkish Oncology Group Kidney Cancer Consortium database

Aim: The authors present real-world data on the efficacy and safety of nivolumab in patients with metastatic renal cell carcinoma (mRCC). Methods: The Turkish Oncology Group Kidney Cancer Consortium (TKCC) database includes patients with mRCC from 13 cancer centers in Turkey. Patients with mRCC treated with nivolumab in the second line and beyond were extracted from the TKCC database. Results: A total of 173 patients were included. The rates of patients treated with nivolumab in the second, third, fourth and fifth lines were 47.4%, 32.4%, 14.5% and 5.7%, respectively. The median overall survival and progression-free survival were 24.2 months and 9.6 months, respectively. Nivolumab was discontinued owing to adverse events in 11 (6.4%) patients. Conclusion: Nivolumab was effective in patients with mRCC and no new safety signal was observed.

Pathology and systemic therapy of non-clear cell renal cell carcinoma: an overview

Introduction: Non-clear cell renal cell carcinoma (nccRCC) represents a highly heterogenous group of kidney cancer entities. As most clinical trials predominantly include patients with clear cell RCC (ccRCC), nccRCC treatment guidelines are mainly extrapolated from recommendations in ccRCC. Here, we review and elucidate current data on the pathologic classification and treatment of nccRCC.Areas covered: This article gives an overview of the WHO classification of RCC, showing the histological diversity of nccRCC and focusing particularly on entities first characterized since 2016, their specific molecular behavior and their role as indicators for hereditary cancer syndromes. In this context, we discuss the available data on nccRCC treatment oprtions such as tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, cytotoxic chemotherapy, and immune checkpoint inhibitors.Expert opinion: Although nccRCCs are relatively uncommon, entities of this type account for a subgroup of up to 20-25% of all RCCs. Advances in histopathology and molecular genetics, together with evidence gained from retrospective and prospective clinical data, have improved understanding of these tumors in recent years. Nevertheless, selective trials of current and novel therapies including new targeted agents in patients with nccRCC are urgently needed to further improve treatment guidelines.

Racial Differences in Clinical Outcomes for Metastatic Renal Cell Carcinoma Patients Treated With Immune-Checkpoint Blockade

BACKGROUND

Immune-checkpoint-inhibitors (ICIs) have become the cornerstone of metastatic renal-cell-carcinoma (mRCC) therapy. However, data are limited regarding clinical outcomes by race. In this study, we compared the real-world outcomes between African American (AA) and Caucasian mRCC patients treated with ICIs.

METHODS

We performed a retrospective study of 198 patients with mRCC who received ICI at the Emory Winship Cancer Institute from 2015-2020. Clinical outcomes were measured by overall survival (OS), progression-free survival (PFS), and overall response rate (ORR) defined as a complete or partial response maintained for at least 6 months per response evaluation criteria in solid tumors version 1.1. Univariate and multivariable analyses were carried out for OS and PFS by Cox proportional-hazard model and ORR by logistical-regression model. Descriptive statistics compared rates of immune-related adverse events (irAEs) and non-clear-cell-RCC (nccRCC) histology were assessed using Chi-square test.

RESULTS

Our cohort was comprised of 38 AA and 160 Caucasian patients. Most were diagnosed with clear-cell-RCC (ccRCC) (78%) and more than half received (57%) PD-1/PD-L1 monotherapy. Most patients were intermediate or poor-risk groups (83%). Comparing to Caucasians, our AA cohort contained more females and nccRCC cases. Kaplan-Meier method showed AAs had no statistically different median OS (17 vs 25 months, p=0.368) and PFS (3.1 vs 4.4 months, p=0.068) relative to Caucasian patients. On multivariable analysis, AA patients had significantly shorter PFS (HR=1.52, 95% CI: 1.01-2.3, p=0.045), similar ORR (OR=1.04, 95% CI: 0.42-2.57, p=0.936) and comparable OS (HR=1.09, 95% CI: 0.61-1.95, p=0.778) relative to Caucasians.

CONCLUSIONS

Our real-world analysis of ICI-treated mRCC patients showed that AAs experienced shorter PFS but similar OS relative to Caucasians. This similarity in survival outcomes is reassuring for the use of ICI amongst real-world patient populations, however, the difference in treatment response is poorly represented in early outcomes data from clinical trials. Thus, the literature requires larger prospective studies to validate these findings.

Hereditary leiomyomatosis and renal cell cancer syndrome - case report and review of the literature

Hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) is an exceptionally rare autosomal dominant condition caused by a germline heterozygous mutation of the fumarate hydratase gene. It manifests as multiple piloleiomyomas, associated with numerous, early-onset uterine leiomyomas in female patients, as well as a highly increased risk of renal cell carcinoma (RCC), most often type 2 papillary RCC. HLRCC has been described in association with adrenal cortical hyperplasia, pheochromocytoma, adrenal cortical carcinoma, and other solid tumors, but the exact relationship between these disorders has not yet been clarified. We present a case of HLRCC associated with bilateral adrenal cortical hyperplasia and discuss the pathogenesis, clinical and paraclinical features of HLRCC, as well as the adequate management of these patients.

The immunology of renal cell carcinoma

Renal cell carcinoma (RCC) is the most common type of kidney cancer and comprises several subtypes with unique characteristics. The most common subtype (~70% of cases) is clear-cell RCC. RCC is considered to be an immunogenic tumour but is known to mediate immune dysfunction in large part by eliciting the infiltration of immune-inhibitory cells, such as regulatory T cells and myeloid-derived suppressor cells, into the tumour microenvironment. Several possible mechanisms have been proposed to explain how these multiple tumour-infiltrating cell types block the development of an effective anti-tumour immune response, including inhibition of the activity of effector T cells and of antigen presenting cells via upregulation of suppressive factors such as checkpoint molecules. Targeting immune suppression using checkpoint inhibition has resulted in clinical responses in some patients with RCC and combinatorial approaches involving checkpoint blockade are now standard of care in patients with advanced RCC. However, a substantial proportion of patients do not benefit from checkpoint blockade. The identification of reliable biomarkers of response to checkpoint blockade is crucial to facilitate improvements in the clinical efficacy of these therapies. In addition, there is a need for the development of other immune-based strategies that address the shortcomings of checkpoint blockade, such as adoptive cell therapies.

Advancing the Science and Management of Renal Cell Carcinoma: Bridging the Divide between Academic and Community Practices

The treatment of metastatic renal cell carcinoma (mRCC) has rapidly evolved; however, the progress made in the field is heavily contingent upon timely and efficient accrual to clinical trials. While a substantial proportion of accrual occurs at tertiary care centers, community sites are playing an increasing role in patient recruitment. In this article, we discuss strategies to optimize collaborations between academic and community sites to facilitate clinical research. Further, as the role of biomarker discovery has become increasingly important in tailoring therapy, we will discuss opportunities to bridge diverse accrual sites for the purpose of translational research.

Renal Cell and Urothelial Carcinoma: Biomarkers for New Treatments

Therapies for genitourinary malignancies have evolved considerably in the past five years. Combination treatment targeting biologically relevant immune and angiogenic pathways is improving patient survival in metastatic renal cell carcinoma (RCC), whereas immune checkpoint blockade (ICB), novel targeted therapy, and antibody drug conjugates have changed the landscape of urothelial cancer (UC) treatment. A daily challenge for clinicians is identifying patients who derive a preferential benefit from the available therapeutic options. The completion of large-scale genomics projects has yielded comprehensive descriptions of the molecular heterogeneity present in RCC and UC, although clinical applications of these data continue to evolve. Major molecular subtypes of RCC align well with histology subtype, and although some molecular characteristics appear to carry prognostic information, biomarkers predicting benefit from tyrosine kinase inhibitor (TKI) or immunotherapy are generally lacking. Unexpectedly, similar work has demonstrated that UC can be grouped into "molecular subtypes" that share properties with those found in breast cancer and other solid tumors. Furthermore, this molecular subtype classification is prognostic and potentially predictive of differential benefit from conventional and targeted therapies. This article provides an update on the current state of molecular biomarker development and potential clinical utility in RCC and UC.

Predictive Value of In Vivo MR Spectroscopy With Semilocalization by Adiabatic Selective Refocusing in Differentiating Clear Cell Renal Cell Carcinoma From Other Subtypes

OBJECTIVE. The purpose of this study is to evaluate the diagnostic value of in vivo MR spectroscopy (MRS) with semilocalization by adiabatic selective refocusing (semi-LASER MRS) in differentiating clear cell renal cell carcinoma (RCC) from the non-clear cell subtype. SUBJECTS AND METHODS. Sixteen patients with biopsy-proven RCC or masses highly suspicious for RCC were prospectively recruited to participate in the study. Single-voxel ¹H spectra were acquired using a 3-T MRI system, with a semi-LASER sequence acquired for renal tumors in 14 patients and for healthy renal tissue (control tissue) in 12 patients. Offline processing of the MR spectra was performed. MRI and spectra analysis were performed independently by radiologists who were blinded to the reference histopathologic findings. RESULTS. Semi-LASER MRS was diagnostic for nine of 11 patients (82%) with histopathologically proven clear cell RCC, showing a strong lipid peak in seven patients and a weaker lipid resonance in two others, whereas control spectra showed weakly positive findings in only one patient. MRS findings were negative for lipid resonance in two of three patients (67%) with non-clear cell tumors and were weakly positive in another patient. Semi-LASER MRS had a high sensitivity and positive predictive value of 82% and 90%, respectively, in addition to a specificity of 67%, a negative predictive value of 50%, and overall accuracy of 79% for the detection of clear cell RCC. Lipid resonance was detected by MRS for four of six clear cell RCCs with no intravoxel fat on chemical-shift MRI. CONCLUSION. The preliminary results of the present study show that semi-LASER MRS is promising for the noninvasive discrimination of clear cell RCC from non-clear cell RCC on the basis of detection of lipid resonance and that it provides an incremental yield compared with chemical-shift MRI.

Eligibility and Radiologic Assessment for Adjuvant Clinical Trials in Kidney Cancer

Purpose

To harmonize the eligibility criteria and radiologic disease assessment definitions in clinical trials of adjuvant therapy for renal cell carcinoma (RCC).

Method

On November 28, 2017, US-based experts in RCC clinical trials, including medical oncologists, urologic oncologists, regulators, biostatisticians, radiologists, and patient advocates, convened at a public workshop to discuss eligibility for trial entry and radiologic criteria for assessing disease recurrence in adjuvant trials in RCC. Multiple virtual meetings were conducted to address the issues identified at the workshop.

Results

The key workshop conclusions for adjuvant RCC therapy clinical trials were as follows. First, patients with non-clear cell RCC could be routinely included, preferably in an independent cohort. Second, patients with T3-4, N+M0, and microscopic R1 RCC tumors may gain the greatest advantages from adjuvant therapy. Third, trials of agents not excreted by the kidney should not exclude patients with severe renal insufficiency. Fourth, therapy can begin 4 to 16 weeks after the surgical procedure. Fifth, patients undergoing radical or partial nephrectomy should be equally eligible. Sixth, patients with microscopically positive soft tissue or vascular margins without gross residual or radiologic disease may be included in trials. Seventh, all suspicious regional lymph nodes should be fully resected. Eighth, computed tomography should be performed within 4 weeks before trial enrollment; for patients with renal insufficiency who cannot undergo computed tomography with contrast, noncontrast chest computed tomography and magnetic resonance imaging of the abdomen and pelvis with gadolinium should be performed. Ninth, when feasible, biopsy should be undertaken to identify any malignant disease. Tenth, when biopsy is not feasible, a uniform approach should be used to evaluate indeterminate radiologic findings to identify what constitutes no evidence of disease at trial entry and what constitutes radiologic evidence of disease. Eleventh, a uniform approach for establishing the date of recurrence should be included in any trial design. Twelfth, patient perspectives on the use of placebo, conditions for unblinding, and research biopsies should be considered carefully during the conduct of an adjuvant trial.

Conclusions and Relevance

The discussions suggested that a uniform approach to eligibility criteria and radiologic disease assessment will lead to more consistently interpretable trial results in the adjuvant RCC therapy setting.

LC-MS based metabolomic profiling for renal cell carcinoma histologic subtypes

Renal cell carcinomas (RCC) are classified according to their histological features. Accurate classification of RCC and comprehensive understanding of their metabolic dysregulation are of critical importance. Here we investigate the use of metabolomic analyses to classify the main RCC subtypes and to describe the metabolic variation for each subtype. To this end, we performed metabolomic profiling of 65 RCC frozen samples (40 clear cell, 14 papillary and 11 chromophobe) using liquid chromatography-mass spectrometry. OPLS-DA multivariate analysis based on metabolomic data showed clear discrimination of all three main subtypes of RCC (R² = 75.0%, Q² = 59.7%). The prognostic performance was evaluated using an independent cohort and showed an AUROC of 0.924, 0.991 and 1 for clear cell, papillary and chromophobe RCC, respectively. Further pathway analysis using the 21 top metabolites showed significant differences in amino acid and fatty acid metabolism between three RCC subtypes. In conclusion, this study shows that metabolomic profiling could serve as a tool that is complementary to histology for RCC subtype classification. An overview of metabolic dysregulation in RCC subtypes was established giving new insights into the understanding of their clinical behaviour and for the development of targeted therapeutic strategies.

Comprehensive Genomic Analysis of Metastatic Non-Clear-Cell Renal Cell Carcinoma to Identify Therapeutic Targets

PURPOSE

Non-clear-cell renal cell carcinoma (nccRCC) encompasses approximately 20% of renal cell carcinomas and includes subtypes that vary in clinical and molecular biology. Compared with clear cell renal cell carcinoma, nccRCC demonstrates limited sensitivity to conventional vascular endothelial growth factor- and mammalian target of rapamycin-directed agents, indicating a need for better therapies. Characterizing the genomic landscape of metastatic nccRCC variants may help define novel therapeutic strategies.

PATIENTS AND METHODS

We retrospectively analyzed tumor tissue from patients with metastatic nccRCC who consented to genomic analysis of their tumor and germline DNA. A hybridization capture-based assay was used to identify single nucleotide variants and small insertions and deletions across more than 340 cancer-associated genes with germline comparison. Clinical actionability of somatic mutations was assessed using OncoKB levels of evidence. Microsatellite instability (MSI) in the tumor was investigated.

RESULTS

Of 116 patients included in the analysis, 57 (49%) presented with de novo metastatic disease, and 59 (51%) presented with localized disease that later metastasized. Subtype classifications included unclassified (n = 41; 35%), papillary (n = 26; 22%), chromophobe (n = 17; 15%), translocation associated (n = 13; 11%), and other (n = 19; 16%). Of all tumors, 15 (13%) had putative driver somatic alterations amenable to targeted therapies, including alterations in MET, TSC1/2, and an ALK translocation. Of 45 patients who had germline testing, 11 (24%) harbored mutations, seven of which could potentially guide therapy. Of 115 available tumors for analysis, two (1.7%) had high and six (5%) had intermediate MSI status.

CONCLUSION

The mutation profiles of metastatic nccRCC vary by subtype. Comprehensive analysis of somatic mutations, germline mutations, and MSI, interpreted via an annotated precision oncology knowledge base, identified potentially targetable alterations in 22% of patients, which merits additional investigation.

An evaluation of nivolumab for the treatment of metastatic renal cell carcinoma

INTRODUCTION

The treatment paradigm for metastatic renal cell carcinoma (mRCC) has undergone a revolution with the rapid market approval of multiple agents over a three-year period. The immunogenicity of renal cell carcinoma (RCC) provided the biological rationale to assess the clinical efficacy of nivolumab, an immune checkpoint inhibitor. Nivolumab is approved for second-line treatment after failure of angiogenesis-targeted therapy and in combination therapy with ipilimumab for previously untreated intermediate- or poor-risk advanced RCC. Areas covered: The authors review the preclinical and clinical data supporting nivolumab employment in mRCC. Discussion of the underlying mechanisms of immunotherapy, data on objective responses, safety and tolerability, regulatory affairs, and future directions of nivolumab therapy are highlighted. Expert opinion: Nivolumab serves as a proof-of-principle of the efficacy of immunotherapy with checkpoint inhibition in mRCC. Nivolumab may be considered the leading monotherapy in the second-line setting for patients with low tumor volume considering its risks and benefits. Nivolumab was recently approved in the first-line setting as part of combination therapy with another immune modulator. Moreover, nivolumab use may offer clinicians the option for treatment beyond progression as emerging data has indicated possible overall survival benefits in this setting. Ongoing clinical studies may result in nivolumab use in the first-line setting, as monotherapy or in combination therapy with antiangiogenesis agents.

Therapeutic Strategies for Hereditary Kidney Cancer

The study of hereditary forms of kidney cancer has vastly increased our understanding of metabolic and genetic pathways involved in the development of both inherited and sporadic kidney cancers. The recognition that diverse molecular events drive different forms of kidney cancers has led to the preclinical and clinical development of specific pathway-directed strategies tailored to treat distinct subgroups of kidney cancer. Here, we describe the molecular mechanisms underlying the pathogenesis of several different types of hereditary renal cancers, review their clinical characteristics, and summarize the treatment strategies for the management of these cancers.

Renal cell carcinoma

Renal cell carcinoma (RCC) denotes cancer originated from the renal epithelium and accounts for >90% of cancers in the kidney. The disease encompasses >10 histological and molecular subtypes, of which clear cell RCC (ccRCC) is most common and accounts for most cancer-related deaths. Although somatic VHL mutations have been described for some time, more-recent cancer genomic studies have identified mutations in epigenetic regulatory genes and demonstrated marked intra-tumour heterogeneity, which could have prognostic, predictive and therapeutic relevance. Localized RCC can be successfully managed with surgery, whereas metastatic RCC is refractory to conventional chemotherapy. However, over the past decade, marked advances in the treatment of metastatic RCC have been made, with targeted agents including sorafenib, sunitinib, bevacizumab, pazopanib and axitinib, which inhibit vascular endothelial growth factor (VEGF) and its receptor (VEGFR), and everolimus and temsirolimus, which inhibit mechanistic target of rapamycin complex 1 (mTORC1), being approved. Since 2015, agents with additional targets aside from VEGFR have been approved, such as cabozantinib and lenvatinib; immunotherapies, such as nivolumab, have also been added to the armamentarium for metastatic RCC. Here, we provide an overview of the biology of RCC, with a focus on ccRCC, as well as updates to complement the current clinical guidelines and an outline of potential future directions for RCC research and therapy.

Hereditary Renal Tumor Syndromes: Update on Diagnosis and Management

Hereditary renal cancers account for approximately 5%-8% of all renal tumors. Over the past 2 decades, a number of syndromes have been identified that predispose patients to early renal cancer development, representing all the major histologic types of tumor pathology. In this article, we describe the current knowledge concerning the cell type, known mechanism of tumor development, other manifestations of the syndrome, imaging findings, genetic screening, and imaging surveillance recommendations for each of the major syndromes associated with hereditary renal cancers.

Molecular analysis of aggressive renal cell carcinoma with unclassified histology reveals distinct subsets

Renal cell carcinomas with unclassified histology (uRCC) constitute a significant portion of aggressive non-clear cell renal cell carcinomas that have no standard therapy. The oncogenic drivers in these tumours are unknown. Here we perform a molecular analysis of 62 high-grade primary uRCC, incorporating targeted cancer gene sequencing, RNA sequencing, single-nucleotide polymorphism array, fluorescence in situ hybridization, immunohistochemistry and cell-based assays. We identify recurrent somatic mutations in 29 genes, including NF2 (18%), SETD2 (18%), BAP1 (13%), KMT2C (10%) and MTOR (8%). Integrated analysis reveals a subset of 26% uRCC characterized by NF2 loss, dysregulated Hippo–YAP pathway and worse survival, whereas 21% uRCC with mutations of MTOR, TSC1, TSC2 or PTEN and hyperactive mTORC1 signalling are associated with better clinical outcome. FH deficiency (6%), chromatin/DNA damage regulator mutations (21%) and ALK translocation (2%) distinguish additional cases. Altogether, this study reveals distinct molecular subsets for 76% of our uRCC cohort, which could have diagnostic and therapeutic implications.

A subset of renal cell carcinomas have uncertain histology and are aggressive in nature. Here, the authors examine this group of unclassified renal cancers using genomics techniques and identify further subclasses of the tumours that have differing prognoses.

Axitinib after Sunitinib in Metastatic Renal Cancer: Preliminary Results from Italian "Real-World" SAX Study

Axitinib is an oral angiogenesis inhibitor, currently approved for treatment of metastatic renal cell carcinoma (mRCC) after failure of prior treatment with Sunitinib or cytokine. The present study is an Italian Multi-Institutional Retrospective Analysis that evaluated the outcomes of Axitinib, in second-line treatment of mRCC. The medical records of 62 patients treated with Axitinib, were retrospectively reviewed. The Progression Free Survival (PFS), the Overall Survival (OS), the Objective Response Rate (ORR), the Disease Control Rate (DCR), and the safety profile of axitinib and sunitinib–axitinib sequence, were the primary endpoint. The mPFS was 5.83 months (95% CI 3.93–7.73 months). When patients was stratified by Heng score, mPFS was 5.73, 5.83, 10.03 months according to poor, intermediate, and favorable risk group, respectively. The mOS from the start of axitinib was 13.3 months (95% CI 8.6–17.9 months); the observed ORR and DCR were 25 and 71%, respectively. When stratified patients by subgroups defined by duration of prior therapy with Sunitinib (≤ vs. >median duration), there was a statistically significant difference in mPFS with 8.9 (95% CI 4.39–13.40 months) vs. 5.46 months (95% CI 4.04–6.88 months) for patients with a median duration of Sunitinib >13.2 months. DCR and ORR to previous Sunitinib treatment was associated with longer statistically mPFS, 7.23 (95% CI 3.95–10.51 months, p = 0.01) and 8.67 (95% CI 4.0–13.33 months, p = 0.008) vs. 2.97 (95% CI 0.65–5.27 months, p = 0.01) and 2.97 months (95% CI 0.66–5.28 months, p = 0.01), respectively. Overall Axitinib at standard schedule of 5 mg bid, was well-tolerated. The most common adverse events of all grades were fatig (25.6%), hypertension (22.6%), gastro-intestinal disorders (25.9%), and hypothyroidism (16.1%). The sequence Sunitinib–Axitinib was well-tolerated without worsening in side effects, with a median OS of 34.7 months (95% CI 18.4–51.0 months). Our results are consistent with the available literature; this retrospective analysis confirms that Axitinib is effective and safe in routine clinical practice.

Mitochondria and Cancer

Decades ago, Otto Warburg observed that cancers ferment glucose in the presence of oxygen, suggesting that defects in mitochondrial respiration may be the underlying cause of cancer. We now know that the genetic events that drive aberrant cancer cell proliferation also alter biochemical metabolism, including promoting aerobic glycolysis, but do not typically impair mitochondrial function. Mitochondria supply energy; provide building blocks for new cells; and control redox homeostasis, oncogenic signaling, innate immunity, and apoptosis. Indeed, mitochondrial biogenesis and quality control are often upregulated in cancers. While some cancers have mutations in nuclear-encoded mitochondrial tricarboxylic acid (TCA) cycle enzymes that produce oncogenic metabolites, there is negative selection for pathogenic mitochondrial genome mutations. Eliminating mtDNA limits tumorigenesis, and rare human tumors with mutant mitochondrial genomes are relatively benign. Thus, mitochondria play a central and multifunctional role in malignant tumor progression, and targeting mitochondria provides therapeutic opportunities.

New strategies in renal cell carcinoma: targeting the genetic and metabolic basis of disease

The development of new forms of treatment of advanced renal cell carcinoma over the past two decades has been primarily focused on targeting the VHL/HIF pathway. The recent identification of mutations of chromatin-remodeling genes in clear-cell renal carcinoma (ccRCC), of genomic heterogeneity, and of a Warburg-like metabolic phenotype in advanced disease has had a profound effect on our understanding of the evolution of ccRCC and on potential approaches to personalized therapy. Early approaches to therapy for patients with advanced type I papillary RCC that have centered around the MET/HGF pathway will expand as more genomic information becomes available. Sporadic and familial type II papillary renal cell carcinoma are characterized by enhanced aerobic glycolysis and share an antioxidant response phenotype. In fumarate hydratase-deficient RCC, fumarate-induced succination of KEAP1 activates Nrf2 signaling. CUL3 and Nrf2 mutations as well as an Nrf2 activation phenotype are found in sporadic type II papillary RCC. Therapeutic approaches designed to target the Nrf2 pathway as well as to impair blood flow and glucose delivery in these cancers that are highly dependent on a robust tumor vasculature and on ready availability of glucose for energy production and glycolysis are in development.

Predictive Value of Chemical-Shift MRI in Distinguishing Clear Cell Renal Cell Carcinoma From Non-Clear Cell Renal Cell Carcinoma and Minimal-Fat Angiomyolipoma

OBJECTIVE

The purpose of this study was to evaluate the diagnostic performance of chemical-shift MRI in the differentiation of clear cell renal cell carcinoma (RCC) from minimal-fat angiomyolipoma (AML) and non-clear cell RCC.

MATERIALS AND METHODS

In this retrospective study, 97 patients with solid renal tumors without macroscopic fat and with a pathologic diagnosis of clear cell RCC (n = 40), non-clear cell RCC (n = 31), or minimal-fat AML (n = 26) who had undergone renal chemical-shift MRI were included. Size, location, morphology, and signal intensity (SI) of the tumors and the contralateral normal kidneys on T2-weighted and in-phase and opposed-phase images were recorded by readers blinded to the pathology. Percentage tumor-to-renal parenchymal SI drop (percentage SI drop) was calculated and correlated to tumor histology. The statistical analysis was done using Kruskal-Wallis, one-way ANOVA, chi-square, and Fisher exact tests.

RESULTS

The percentage SI drop was significantly higher in clear cell RCC compared with non-clear cell RCC and minimal-fat AML (p < 0.001). Percentage SI drop of greater than 20% had 57.5% sensitivity, 96.5% specificity, and 92% positive predictive value (PPV); and percentage SI drop greater than 29% had 40% sensitivity and 100% specificity for diagnosis of clear cell RCC within the cohort of clear cell RCC, minimal-fat AML, and non-clear cell RCC. A significant proportion of minimal-fat AML (46.2%) displayed homogeneous low T2-weighted SI as opposed to clear cell RCC (5%) and non-clear cell RCC (29%) (p < 0.001).

CONCLUSION

The percentage SI drop on chemical-shift MRI had high specificity and moderate sensitivity in predicting clear cell RCC over non-clear cell RCC and minimal-fat AML. A percentage SI drop greater than 20% in a renal mass without macroscopically visible fat has high PPV for clear cell RCC over minimal-fat AML and non-clear cell RCC. Among morphologic features, homogeneous low T2 SI favors minimal-fat AML over RCC.

Hypertension and Circulating Cytokines and Angiogenic Factors in Patients With Advanced Non-Clear Cell Renal Cell Carcinoma Treated With Sunitinib: Results From a Phase II Trial

BACKGROUND

We evaluated the significance of hypertension developing during vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor (VEGFR-TKI) treatment and a group of cytokines and angiogenic factors (CAFs) in advanced non-clear cell renal cell carcinoma (nccRCC) patients treated with sunitinib in a phase II study.

MATERIALS AND METHODS

Using multiplex assays, we analyzed the levels of 38 CAFs in plasma at baseline and after 4 weeks of sunitinib therapy. Sunitinib benefit was defined as a partial response or stable disease using the Response Evaluation Criteria in Solid Tumors lasting ≥4 months. Cox proportional hazards regression models were used to assess the associations among hypertension, CAFs, and progression-free (PFS) and overall survival (OS).

RESULTS

Fifty-seven patients were evaluable; 53 had baseline CAF levels available. The median PFS and OS were 2.9 months (95% confidence interval [CI], 1.4-5.5) and 16.8 months (95% CI, 10.7-27.4), respectively. Sunitinib benefit was observed in 21 patients (37%). However, 33 patients (60%) developed hypertension during treatment, although no association was found with survival or response. Elevated baseline soluble tumor necrosis factor (TNF) receptor I, interleukin-8, growth-regulated oncogene, transforming growth factor-α, and VEGFR-2 levels were associated with an increased risk of death on multivariate analysis.

CONCLUSION

We found no association between the development of hypertension and survival or sunitinib benefit in advanced nccRCC. TNF and angiogenic/immunomodulatory mediators were identified for evaluation as markers of prognosis and VEGFR-TKI benefit in future studies.

Research into cancer metabolomics: Towards a clinical metamorphosis

The acknowledgement that metabolic reprogramming is a central feature of cancer has generated high expectations for major advances in both diagnosis and treatment of malignancies through addressing metabolism. These have so far only been partially fulfilled, with only a few clinical applications. However, numerous diagnostic and therapeutic compounds are currently being evaluated in either clinical trials or pre-clinical models and new discoveries of alterations in metabolic genes indicate future prognostic or other applicable relevance. Altogether, these metabolic approaches now stand alongside other available measures providing hopes for the prospects of metabolomics in the clinic. Here we present a comprehensive overview of both ongoing and emerging clinical, pre-clinical and technical strategies for exploiting unique tumour metabolic traits, highlighting the current promises and anticipations of research in the field.

Metastatic non-clear cell renal cell carcinoma: an evidence based review of current treatment strategies

Much progress has been made in the treatment of metastatic renal cell carcinoma (RCC) over the last decade, with the development of agents that block the vascular endothelial growth factor (VEGF) pathway or the mammalian target of rapamycin (mTOR) pathway. The incorporation of these agents into treatment algorithms has been the result of carefully conducted clinical trials leading to Food and Drug Administration (FDA) approval and subsequent adoption as the current standard of care. These trials, however, were dominated by patients with clear cell renal cell carcinoma (ccRCC), and little data are currently available on the treatment of non-clear cell renal cell carcinoma (nccRCC). nccRCC encompasses a biologically heterogeneous group of kidney tumors that portend very diverse prognoses and responses to therapy. This review is a pathway based approach that highlights the current systemic treatment strategies for metastatic nccRCC.

Modulation of the myeloid compartment of the immune system by angiogenic- and kinase inhibitor-targeted anti-cancer therapies

Targeted therapies were rationally designed to inhibit molecular pathways in tumor cells critically involved in growth and survival; however, many drugs used in targeted therapies may affect the immune system. In addition, selected conventional chemotherapeutic agents have also been reported to be endowed with direct or indirect effects on immunity, for instance via immunogenic death of tumors. Thus, cancer therapies may have off-target effects, some of which are directed to the immune system. Here, we will review some of these effects in specific therapeutic approaches. We will examine the modulation of the immune contexture in human sarcoma and melanoma induced by anti-angiogenic therapies and by BRAF inhibitors, respectively. We will then discuss how the anti-tumor agent trabectedin is selectively cytotoxic to cells of the monocytic-macrophage lineage and how these immune-related effects can be part of the response to treatment.

Renal cell carcinoma

The treatment of renal cell carcinoma (RCC) has changed greatly over the past 15 years. Progress in the surgical management of the primary tumor and increased understanding of the molecular biology and genomics of the disease have led to the development of new therapeutic agents. The management of the primary tumor has changed owing to the realization that clean margins around the primary lesion are sufficient to prevent local recurrence, as well as the development of more sophisticated tools and techniques that increase the safety of partial nephrectomy. The management of advanced disease has altered even more dramatically as a result of new agents that target the tumor vasculature or that attenuate the activation of intracellular oncogenic pathways. This review summarizes data from prospective randomized phase III studies on the surgical management and systemic treatment of RCC, and provides an up to date summary of the histology, genomics, staging, and prognosis of RCC. It describes the management of the primary tumor and offers an overview of systemic agents that form the mainstay of treatment for advanced disease. The review concludes with an introduction to the exciting new class of immunomodulatory agents that are currently in clinical trials and may form the basis of a new therapeutic approach for patients with advanced RCC.

The impact of genetic heterogeneity on biomarker development in kidney cancer assessed by multiregional sampling

Primary clear cell renal cell carcinoma (ccRCC) genetic heterogeneity may lead to an underestimation of the mutational burden detected from a single site evaluation. We sought to characterize the extent of clonal branching involving key tumor suppressor mutations in primary ccRCC and determine if genetic heterogeneity could limit the mutation profiling from a single region assessment. Ex vivo core needle biopsies were obtained from three to five different regions of resected renal tumors at a single institution from 2012 to 2013. DNA was extracted and targeted sequencing was performed on five genes associated with ccRCC (von-Hippel Lindau [VHL], PBRM1, SETD2, BAP1, and KDM5C). We constructed phylogenetic trees by inferring clonal evolution based on the mutations present within each core and estimated the predictive power of detecting a mutation for each successive tumor region sampled. We obtained 47 ex vivo biopsy cores from 14 primary ccRCC's (median tumor size 4.5 cm, IQR 4.0–5.9 cm). Branching patterns of various complexities were observed in tumors with three or more mutations. A VHL mutation was detected in nine tumors (64%), each time being present ubiquitously throughout the tumor. Other genes had various degrees of regional mutational variation. Based on the mutations' prevalence we estimated that three different tumor regions should be sampled to detect mutations in PBRM1, SETD2, BAP1, and/or KDM5C with 90% certainty. The mutational burden of renal tumors varies by region sampled. Single site assessment of key tumor suppressor mutations in primary ccRCC may not adequately capture the genetic predictors of tumor behavior.