Prognostic Role of PD-L1 Expression in Renal Cell Carcinoma. A Systematic Review and Meta-Analysis

Novel emerging biomarkers to immunotherapy in kidney cancer

The treatment of metastatic renal cell carcinoma has significantly evolved in recent years, particularly with the advent of novel immune checkpoint inhibitors (ICI). Despite the striking benefits observed on a population level, outcomes vary and some patients do not respond to ICI-based regimens, ultimately require salvage therapies. An ever deeper understanding of the disease biology mediated by the development of multiple high-throughput molecular omics has led to significant progress in biomarkers discovery. But despite growing insights into the molecular underpinnings of the tumor microenvironment, biomarkers have not been integrated successfully into clinical practice. In this review, we discuss some of the novel emerging predictive biomarkers to ICIs in metastatic renal cell carcinoma.

Gene signatures with therapeutic value: emerging perspective for personalized immunotherapy in renal cancer

Renal cancer is one of the deadliest urogenital diseases. In recent years, the advent of immunotherapy has led to significant improvement in the management of patients with renal cancer. Although cancer immunotherapy and its combinations had benefited numerous patients, several challenges need to be addressed. Apart from the high costs of treatment, the lack of predictive biomarkers and toxic side-effects have impeded its wider applicability. To address these issues, new biomarkers are required to predict responsiveness and design personalized treatment strategies. Recent advances in the field of single-cell sequencing and multi-dimensional spatial transcriptomics have identified clinically relevant subtypes of renal cancer. Furthermore, there is emerging potential for gene signatures based on immune cells, non-coding RNAs, and pathways such as metabolism and RNA modification. In this review article, we have discussed recent progress in the identification of gene signatures with predictive and prognostic potential in renal cancer.

First-Line Treatment of Metastatic Clear Cell Renal Cell Carcinoma: What Are the Most Appropriate Combination Therapies?

The development of antiangiogenic treatments, followed by immune checkpoint inhibitors (ICI), has significantly changed the management of metastatic clear cell renal cell cancer. Several phase III trials show the superiority of combination therapy, dual immunotherapy (ICI-ICI) or ICI plus tyrosine kinase inhibitors (TKI) of the vascular endothelium growth factor (VEGF) over sunitinib monotherapy. The question is therefore what is the best combination for a given patient? A strategy based on the International Metastatic Database Consortium (IMDC) classification is currently recommended with pembrolizumab + axitinib, cabozantinib + nivolumab, and lenvatinib + pembrolizumab (for all patients) or nivolumab + ipilimumab (for patients with intermediate or poor risk), which are the first-line treatment standards of care. However, several issues remain unresolved and require further investigation, such as the PD-L1 status, the relevance of possible options based on the patient's profile, and consideration of second-line and subsequent treatments.

Biomarkers in renal cell carcinoma: Are we there yet?

Management of kidney cancer has undergone a paradigm shift with the approval of new therapies over the last two decades. Although these drugs have improved clinical outcomes in patients with kidney cancer, there are still a large number of patients who do not show objective responses. A multitude of investigators, including those for The Cancer Genome Atlas have biologically characterized and sub-classified kidney cancer. However, we have not been able to identify molecular targets to effectively treat patients with kidney cancer. As we familiarize ourselves with newer drugs for patients with kidney cancer, it is important to understand that these drugs may not work in every patient and instead may expose patients to unnecessary toxic effects along with burdening society with the financial impact. As we head toward the era of "precision medicine", validated biomarkers are being utilized to guide treatment choices and help identify pathways of resistance in other tumor types. The current review aims at evaluating the progress made so far in this realm for patients with kidney cancer.

Evaluation of circulating PD-1 and PD-L1 as diagnostic biomarkers in dogs with tumors

Background

Programmed cell death protein-1 (PD-1) and programmed cell death ligand-1 (PD-L1) have important roles in tumor evasion of the immune system.

Objectives

This study aimed to assess the diagnostic utility of circulating PD-1 and PD-L1 levels in healthy dogs and dogs with tumors.

Methods

Circulating PD-1 and PD-L1 levels in the serum of 71 dogs with tumors were compared with those of 52 healthy dogs by performing enzyme-linked immunosorbent assay (ELISA).

Results

The ELISA results revealed higher circulating PD-1 and PD-L1 levels in dogs with tumors (2.9 [2.2–3.7] ng/mL; median [IQR] and 2.4 [1.4–4.4] ng/mL, respectively) than in healthy dogs (2.4 [1.9–3.0] ng/mL; p = 0.012 and 1.4 [0.9–2.1] ng/mL; p < 0.001, respectively). Especially, there was a significant difference in circulating PD-1 levels between healthy dogs and dogs with malignant epithelial tumors (2.4 [1.9–3.0] ng/mL and 3.1 [2.6–4.4] ng/mL, respectively; p < 0.01). In addition, there was a significant difference in circulating PD-L1 levels between healthy dogs and dogs with lymphomas (1.4 [0.9–2.1] ng/mL and 2.7 [1.6–5.8] ng/mL, respectively; p < 0.001).

Conclusion

This study indicates that circulating PD-1 and PD-L1 have potential as tumor diagnostic biomarkers in dogs with tumors.

Immune Checkpoint Inhibitor in First-Line Treatment of Metastatic Renal Cell Carcinoma: A Review of Current Evidence and Future Directions

The incidence of renal cell carcinoma (RCC) is rising and metastatic RCC carries a very poor prognosis. The treatment paradigm for metastatic RCC has shifted dramatically in the last decade with multi-targeted tyrosine kinase inhibitors (TKI) previously used as first-line treatment but its utility is limited by short-lived efficacy and rapid disease progression. The dysregulation of immune cells in the tumour microenvironment contributes to unregulated growth of RCC. Thus, the use of immune checkpoint inhibitors has become first-line treatment for metastatic RCC and has offered dramatic improvement in clinical benefit and survival. Treatment with immune checkpoint inhibitor in combination with TKI appears to be promising in offering even greater response rates. The treatment for metastatic RCC continues to evolve and ongoing advances with new targeted agents and biomarkers are needed to continue to improve prognosis in the future.

Nivolumab Reduces PD1 Expression and Alters Density and Proliferation of Tumor Infiltrating Immune Cells in a Tissue Slice Culture Model of Renal Cell Carcinoma

Simple Summary

Immune checkpoint inhibitors (ICIs) have become a first-choice therapy option in the treatment of clear cell renal cell carcinoma (ccRCC). A predictive biomarker is urgently needed since not all patients respond and adverse events occur. Therefore, an ex vivo tissue slice culture (TSC) model was tested to investigate the effects of nivolumab on tumor infiltrating immune cells (TIIC). A decrease in programmed death receptor 1 expression, as well as effects on density and proliferation of TIIC, were observed. Thus, the TSC model could serve as a test platform for response prediction to ICIs.

Abstract

Background: In the treatment of clear cell renal cell carcinoma (ccRCC), nivolumab is an established component of the first-line therapy with a favorable impact on progression free survival and overall survival. However, treatment-related adverse effects occur and, to date, there is no approved predictive biomarker for patient stratification. Thus, the aim of this study was to establish an ex vivo tissue slice culture model of ccRCC and to elucidate the impact of nivolumab on tumor infiltrating immune cells. Methods: Fresh tumor tissue of ccRCC was treated with the immune checkpoint inhibitor nivolumab using ex vivo tissue slice culture (TSC). After cultivation, tissue slices were formalin-fixed, immunohistochemically stained and analyzed via digital image analysis. Results: The TSC model was shown to be suitable for ex vivo pharmacological experiments on intratumoral immune cells in ccRCC. PD1 expression on tumor infiltrating immune cells was dose-dependently reduced after nivolumab treatment (p < 0.01), whereas density and proliferation of tumor infiltrating T-cells and cytotoxic T-cells were inter-individually altered with a remarkable variability. Tumor cell proliferation was not affected by nivolumab. Conclusions: This study could demonstrate nivolumab-dependent effects on PD1 expression and tumor infiltrating T-cells in TSC of ccRCC. This is in line with results from other scientific studies about changes in immune cell proliferation in peripheral blood in response to nivolumab. Thus, TSC of ccRCC could be a further step to personalized medicine in terms of testing the response of individual patients to nivolumab.

[Biomarkers for renal cell tumours]

During the last three decades, renal tumours have become increasingly well differentiated on the basis of their histopathological and molecular features. This subtyping has increasingly impacted clinical practice because more therapeutic options are available in organ-confined and metastatic renal cell tumours. The knowledge of the underlying molecular alterations is essential to develop molecular targeted therapies and to select the most effective systemic therapy for each patient. This manuscript gives an overview of the molecular differentiation on the one hand, and on diagnostic, prognostic and predictive biomarkers on the other hand.

Development and initial clinical testing of a multiplexed circulating tumor cell assay in patients with clear cell renal cell carcinoma

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.

Prognostic value of programmed death-ligand 1 status in Japanese patients with renal cell carcinoma

Background

Programmed death-ligand 1 (PD-L1) positivity is associated with poor prognosis in renal cell carcinoma (RCC). Because the prognostic impact and effect of confounding factors are less known, we investigated the prognostic significance of PD-L1 expression in Japanese patients with recurrent/metastatic RCC who started systemic therapy in 2010–2015.

Methods

This multicenter, retrospective study recruited patients from 29 Japanese study sites who had prior systemic therapy for RCC (November 2018 to April 2019) and stored formalin-fixed paraffin-embedded primary lesion samples. The primary outcome was overall survival (OS) by PD-L1 expression. Secondary outcomes included OS in subgroups and duration of first- and second-line therapies by PD-L1 expression. OS distributions were estimated using Kaplan–Meier methodology.

Results

PD-L1 expression (on immune cells [IC] ≥ 1%) was observed in 315/770 (40.9%) patients. PD-L1 positivity was more prevalent in patients with poor risk per both Memorial Sloan Kettering Cancer Center [MSKCC] and International Metastatic RCC Database Consortium, and high-risk pathological features (higher clinical stage, nuclear grade and sarcomatoid features). Median OS for PD-L1–positive patients was 30.9 months (95% CI 25.5–35.7) versus 37.5 months (95% CI 34.0–42.6) for PD-L1–negative patients (HR 1.04 [90% CI 0.89–1.22, p = 0.65]; stratified by MSKCC risk and liver metastases). Propensity score weight (PSW)-adjusted OS was similar between PD-L1–positive and –negative patients (median 34.4 versus 31.5 months; estimated PSW-adjusted HR 0.986).

Conclusions

This study suggests PD-L1 status was not an independent prognostic factor in recurrent/metastatic RCC during the study period because PD-L1 positivity was associated with poor prognostic factors, especially MSKCC risk status.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10147-021-01993-x.

PD-1 Expression and its Correlation With Prognosis in Clear Cell Renal Cell Carcinoma

BACKGROUND/AIM

Programmed death ligand-1 (PD-L1) and programmed death protein 1 (PD-1) expression levels in many tumors and their correlation with prognosis have been actively studied. However, studies on PD-1 expression and its prognostic value in clear cell renal cell carcinoma (ccRCC) are limited and controversial. In this study, we describe the expression of PD-1 and its prognostic significance and association with clinical features in patients with ccRCC.

MATERIALS AND METHODS

We obtained clinicopathological data from 166 patients with ccRCC who were treated at Gyeongsang National University Hospital, Jinju, Korea between January 2000 and December 2009. Tissue microarray blocks were made using representative paraffin blocks of ccRCC specimens. Two pathologists analyzed PD-L1 and PD-1 expression in both tumor and inflammatory cells.

RESULTS

PD-1 expression in tumor-infiltrating inflammatory cells was significantly correlated with unfavorable disease-free survival (DFS) (p<0.001) and disease-specific survival (DSS) (p=0.002) in the univariate analysis. A statistically significant correlation between PD-1 expression and unfavorable DFS (p=0.025) was observed in the multivariate analysis.

CONCLUSION

PD-1 expression in tumor-infiltrating inflammatory cells serves as an independent prognostic factor for unfavorable DSS in patients with ccRCC.

PD-L1 Expression in Endocervical Adenocarcinoma: Correlation With Patterns of Tumor Invasion, CD8+ Tumor-infiltrating Lymphocytes, and Clinical Outcomes

Programmed death-1 ligand (PD-L1) expression has been used as a predictive marker for response to immune checkpoint inhibitors and has been reported to have prognostic value. Its prevalence and significance in endocervical adenocarcinoma (ECA) remain underinvestigated. We evaluated PD-L1 expression and CD8+ tumor-infiltrating lymphocyte density in whole tissue sections of 89 ECAs. PD-L1 expression was observed in 68% of ECAs by combined positive score (CPS, cutoff 1) and 29% of ECAs by tumor proportion score (TPS, cutoff 1%). Using CPS, PD-L1 expression was seen in 11%, 78%, and 72% of pattern A, B, and C tumors, respectively, with significantly higher expression in tumors with destructive-type invasion (B and C) (P=0.001 [A vs. B], 0.0006 [A vs. C], 0.0002 [A vs. B+C]). Using TPS, no significant difference in PD-L1 expression was seen between tumors with different invasion patterns (0%, 22%, and 32% in tumors with pattern A, B, and C, respectively; P=0.27 [A vs. B], 0.053 [A vs. C], 0.11 [A vs. B+C]). PD-L1-positive ECAs demonstrated significantly higher CD8+ tumor-infiltrating lymphocyte density (CPS: P=0.028; TPS: P=0.013) and worse progression-free survival when compared with PD-L1-negative ECAs (CPS: hazard ratio [HR]=4.253 vs. 0.235, P=0.025; TPS: HR=4.98 vs. 0.2; P=0.004). When invasion patterns were separately assessed, pattern C tumors similarly showed worse progression-free survival in PD-L1-positive tumors (CPS: HR=6.15 vs. 0.16, P=0.045; TPS: HR=3.78 vs. 0.26, P=0.027). In conclusion, our data show frequent PD-L1 expression in ECA with destructive-type invasion, supporting the role of the PD-1/PD-L1 pathway as a therapeutic target for these tumors. Our data also support PD-L1 as a negative prognostic marker associated with a potentially unfavorable outcome.

Individualizing renal cell carcinoma treatment through biomarkers discovery in the era of immune checkpoint inhibitors: where do we stand?

PURPOSE OF REVIEW

The treatment landscape of metastatic renal cell carcinoma has greatly evolved over the past fifteen years, leading to a significant improvement in the outcome of our patients. However, there is still an urgent need for predictive biomarkers that could guide our treatment selection, especially in the present era of immune-based treatments.

RECENT FINDINGS

A number of putative biomarkers of immunotherapy activity have been proposed over the past few years, including PD-L1 immunohistochemical expression, tumor mutational burden, neoantigens load, insertions and deletions, complex gene signatures, as well as lymphocytic subpopulations (either circulating or tumor-infiltrating). However, despite preliminary intriguing findings, no biomarker for immune checkpoint activity has emerged so far, that could be used in everyday clinical practice, mainly due to preliminary, or frankly, conflicting results.

SUMMARY

The quest for an 'ideal' biomarker, which should be characterized by adequate specificity, sensibility, predictive (and not just prognostic) value, robustness, reproducibility, ease of evaluation and low cost, is still ongoing.

Checkpoint inhibitors in metastatic papillary renal cell carcinoma

Papillary Renal Cell Carcinoma (pRCC) is the most common non-clear cell RCC (nccRCC) and a distinct entity, although heterogenous, associated with poor outcomes. The treatment landscape of metastatic pRCC (mpRCC) relied so far on targeted therapies, mimicking previous developments in metastatic clear-cell renal cell carcinoma. However, antiangiogenics as well as mTOR inhibitors retain only limited activity in mpRCC. As development of immune checkpoint inhibitors (ICI) is now underway in patients with mpRCC, we aimed at discussing early activity data and potential for future therapeutic strategies in monotherapy or combination. Expression of immune checkpoints such as PD-L1 and infiltrative immune cells in pRCC could provide insights into their potential immunogenicity, although this is currently poorly described. Based on retrospective and prospective data, efficacy of ICI as single agent remains limited. Combinations with tyrosine-kinase inhibitors, notably with anti-MET inhibitors, harbor promising response rates and may enter the standard of care in untreated patients. Collaborative work is needed to refine the molecular and immune landscape of pRCC, and pursue efforts to set up predictive biomarker-driven clinical trials in these rare tumors.

Metastatic Renal Cell Carcinoma Management: From Molecular Mechanism to Clinical Practice

The therapeutic sc"enario of metastatic renal cell cancer (mRCC) has noticeably increased, ranging from the most studied molecular target therapies to those most recently introduced, up to immune checkpoint inhibitors (ICIs). The most recent clinical trials with an ICI-based combination of molecular targeted agents and ICI show how, by restoring an efficient immune response against cancer cells and by establishing an immunological memory, it is possible to obtain not only a better radiological response but also a longer progression-free and overall survival. However, the role of tyrosine kinase inhibitors (TKIs) remains of fundamental importance, especially in patients who, for clinical characteristics, tumor burden and comorbidity, could have greater benefit from the use of TKIs in monotherapy rather than in combination with other therapies. However, to use these novel options in the best possible way, knowledge is required not only of the data from the large clinical trials but also of the biological mechanisms, molecular pathways, immunological mechanisms, and methodological issues related to both new response criteria and endpoints. In this complex scenario, we review the latest results of the latest clinical trials and provide guidance for overcoming the barriers to decision-making to offer a practical approach to the management of mRCC in daily clinical practice. Moreover, based on recent literature, we discuss the most innovative combination strategies that would allow us to achieve the best clinical therapeutic results.

Pembrolizumab plus axitinib for the treatment of advanced renal cell carcinoma

Introduction: The dominant paradigm of sequential therapy of metastatic renal cell carcinoma (mRCC) with single agents has recently been challenged by improved outcomes obtained with combined regimens with immune checkpoint inhibitors. These combined regimens include the combination of pembrolizumab plus axitinib.Areas covered: Here, we provide a brief overview of the current clinical data on the pembrolizumab plus axitinib combination including mechanism of action, pharmacokinetics, efficacy and safety profile.Expert opinion: Both agents targeting the vascular endothelial growth factor (VEGF) pathway and immune checkpoint inhibitors are active as single agents in mRCC. Improved outcomes have been demonstrated in phase 3 trials in comparison with sunitinib for the combinations of axitinib plus pembrolizumab, axitinib plus avelumab, bevacizumab plus atezolizumab, and ipilimumab plus nivolumab. Among these combinations, an OS benefit has, so far, demonstrated only for the combinations of axitinib with pembrolizumab and ipilimumab with nivolumab. Although there are currently no prospective data comparing the combination of ipilimumab and nivolumab with the combination of immune checkpoint inhibitors and VEGF inhibitors, currently available retrospective analyses indicate that these two approaches achieve comparable outcomes.

Current and emerging therapies for first line treatment of metastatic clear cell renal cell carcinoma

The therapeutic landscape for advanced clear cell renal cell carcinoma (ccRCC) is rapidly evolving with improved knowledge of the biology of disease leading to the incorporation of a variety of antiangiogenic agents and immunotherapies. In this review, we discuss historical, current, and emerging first line treatment options for patients with advanced ccRCC. These include data with single agent vascular endothelial growth factor receptor tyrosine kinase inhibitors (TKIs): sunitinib, pazopanib and cabozantinib as well as the recently reported results for the combination of lenvatinib and everolimus (mTOR inhibitor). We also discuss results of the nivolumab anti-programmed cell death (PD-1)/ipilimumab (anti-cytotoxic T lymphocyte-associated antigen 4) combination as well as emerging front-line data with nivolumab and pembrolizumab (anti-PD-1) monotherapy. Finally, we review data supporting recent approvals of TKI and anti-PD-1 or anti-PD-Ligand 1 (PD-L1) combinations (e.g., axitinib/pembrolizumab, axitinib/avelumab and cabozantinib/nivolumab) and initial outcomes of lenvatinib (multi-kinase inhibitor) and pembrolizumab. With many individual and combination treatment options and the lack of head-to-head comparisons, treatment selection will depend on the goals of therapy (endpoints) and the identification and validation of clinical and tumor-based predictive biomarkers that are linked to the desired treatment endpoints.

PD1 and PD-L1 Inhibitors for the Treatment of Kidney Cancer: The Role of PD-L1 Assay

BACKGROUND

Immune checkpoint inhibitors targeting the programmed death receptor ligand 1 (PD-L1)/programmed death receptor 1 (PD-1) pathway represent a drastic change in the treatment landscape of RCC resulting in a dynamic and evolving scenario. There is an urgent need for predictive biomarkers of response to provide a personalized therapeutic strategy for individual patients.

OBJECTIVE

In this review, we focused on trials that investigated the administration of a PD-1 and PDL1 inhibitor alone or in combination with another agent and compared the different assays applied in each trial to evaluate the role of PD-L1 as a prognostic and predictive biomarker.

CONCLUSION

So far, the use of PD-L1 expression alone is not sufficient to predict treatment response and present many limitations: the lack of consensus between different methodologies on biomarker assessment, the heterogeneity of PD-L1 between primary tumors and metastatic sites, different criteria of response to therapy (RECIST vs. irRECIST), the complex interplay with inflammatory components, previous treatments, administration of antibiotic therapy. Combinations of different biomarkers and biological features, such as gene expression associated with angiogenesis, immune response and myeloid inflammation are promising biological variables that need to be validated in the context of prospective clinical trials.

Individualizing Systemic Therapies in First Line Treatment and beyond for Advanced Renal Cell Carcinoma

Therapeutic options for treating advanced renal cell cancer (RCC) are rapidly evolving. Vascular endothelial growth factor (VEGF)-directed therapy, predominantly VEGF receptor (VEGFr) tyrosine kinase inhibitors (TKIs) had been the most effective first line treatment since 2005 irrespective of International Metastatic RCC Database Consortium (IMDC) risk stratification. However, immune checkpoint inhibitors (ICI) have recently changed the treatment paradigm for advanced RCC particularly as the first-line systemic treatment modality. The combination of Ipilimumab and Nivolumab provides better disease control and long-term outcomes compared with the anti-VEGFr TKI Sunitinib for IMDC intermediate- to poor-risk patients and we now have the option of using ICI with TKI upfront for all IMDC risk groups. This poses a challenge for physicians, both to select the most suitable first line regimen and the most suitable subsequent therapy given the lack of data about sequencing in this setting. This treatment landscape is expected to become more complex with the emerging treatment options. Moreover, these therapeutic options cannot be generalized as significant variability exists between individual's disease biologies and their physiologies for handling treatment adverse effects. Notable efforts are being made to identify promising predictive biomarkers ranging from neo-antigen load to gene expression profiling. These biomarkers need prospective validation to justify their utility in clinical practice and in treatment decision making. This review article discusses various clinicopathological characteristics that should be carefully evaluated to help select appropriate treatment and discusses the current status of biomarker-based selection.

The Predictive Value of Programmed Death Ligand 1 in Patients with Metastatic Renal Cell Carcinoma Treated with Immune-checkpoint Inhibitors: A Systematic Review and Meta-analysis

CONTEXT

Immune-checkpoint inhibitors (ICIs) are a mainstay treatment of metastatic renal cell carcinoma (mRCC). As not all patients benefit from ICIs, a biomarker-driven clinical decision-making strategy is desirable.

OBJECTIVE

To assess the predictive value of programmed death ligand 1 (PD-L1) in mRCC patients treated with ICIs.

EVIDENCE ACQUISITION

Multiple databases were searched for articles published up to April 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Studies comparing objective response rate (ORR), complete response rate (CRR), progressive disease rate (PDR), or progression-free survival (PFS) based on tumor PD-L1 status in mRCC patients were eligible.

EVIDENCE SYNTHESIS

Six studies matched our eligibility criteria. Treatment with ICIs was associated with significantly higher ORRs and CRRs, and lower PDRs in patients with PD-L1-positive tumors than in those with PD-L1-negative status (odds ratio [OR] 1.84, 95% confidence interval [CI] 1.48-2.28; OR 3.11, 95% CI 2.04-4.75; and OR 0.43, 95% CI 0.31-0.60, respectively). ICI treatment was associated with significantly better PFS in PD-L1-positive patients than in sunitinib-treated patients (hazard ratio 0.65, 95% CI 0.57-0.74), whereas this was not found in patients with PD-L1-negative tumors. Compared with sunitinib, ICI combination therapy improved ORRs and PFS significantly in PD-L1-positive patients of all examined ICIs. Nivolumab plus ipilimumab had the highest likelihood of providing the highest ORR and longest PFS in PD-L1-positive patients.

CONCLUSIONS

PD-L1 positivity of the tumor is associated with improved ORRs and prolonged PFS in mRCC patients receiving ICI treatment and thus helps identify mRCC patients most likely to benefit from ICI treatment.

PATIENT SUMMARY

The use of an immune-checkpoint inhibitor for the treatment of metastatic renal cell carcinoma (mRCC) improved oncological outcomes, and the status of programmed death ligand 1 could contribute to guiding patients and clinicians when determining personalized treatment strategies for mRCC.

PD-L1 Expression and CD8+ Tumor-infiltrating Lymphocytes in Different Types of Tubo-ovarian Carcinoma and Their Prognostic Value in High-grade Serous Carcinoma

The prevalence and significance of programmed death-1 ligand (PD-L1) expression in different types of tubo-ovarian carcinoma have not been well defined. We evaluated PD-L1 expression and CD8 tumor-infiltrating lymphocyte (TIL) density in whole tissue sections of 189 cases of tubo-ovarian carcinoma, including high-grade serous carcinoma (HGSC, n=100), clear cell carcinoma (CCC, n=24), endometrioid carcinoma (EmC, n=40), and mucinous carcinomas (MC, n=25). Using the tumor proportion score (TPS) with a 1% cutoff, PD-L1 expression was present in 21% of HGSC, 16.7% of CCC, 2.5% of EmC, and 4% of MC. Using the combined positive score (CPS) with a cutoff of 1, PD-L1 expression was present in 48% of HGSC, 25% of CCC, 20% of EmC, and 24% of MC. HGSC demonstrated significantly higher CD8 TIL density than CCC (P=0.013238), EmC (P=0.01341), or MC (P=0.004556). In HGSC, CD8 TIL density was directly correlated with PD-L1 positivity using either TPS (P=0.0008) or CPS (P=0.00011). Survival analysis of patients with high stage (stage III to IV) HGSC revealed PD-L1 positivity by TPS to be associated with improved progression-free survival (adjusted hazard ratio: 0.4912 vs. 2.036, P=0.0378). Although not statistically significant, a similar trend was observed in overall survival (adjusted hazard ratio: 0.3387 vs. 2.953, P=0.0548). In contrast, with CPS, no significant difference was identified between PD-L1-positive and negative groups in either progression-free survival (P=0.5086) or overall survival (P=0.7823). Neoadjuvant chemotherapy was associated with higher PD-L1 expression by TPS (P=0.00407) but not CPS. No significant difference in PD-L1 expression was detected in tumors from patients with germline BRCA1/2 mutations compared with germline mutation-negative tumors by either TPS or CPS. In conclusion, the prevalence of PD-L1 expression is variable in different types of tubo-ovarian carcinoma and is highest in HGSC. In high-stage HGSC, PD-L1 positivity in tumor cells is associated with an increased immune response and improved survival.

The clinicopathological features and prognosis of primary pulmonary lymphoepithelioma-like carcinoma: A systematic review and meta-analysis

BACKGROUND

Primary pulmonary lymphoepithelioma-like carcinoma (PPLELC) was a sparse subtype of unclassified lung cancer. The clinicopathologic features, prognostic factors and multimodality treatment regimens of LELC remain inconclusive. We conducted this systematic review and meta-analysis to address this deficit in current knowledge.

METHODS

We searched PubMed, Embase, and Web of Science to filtrate studies investigating on clinical features and prognostic factors of LELC up to Sep 9th, 2020. Fixed and random effect models were generated to present the incorporated hazard ratios (HR) and odds ratios (OR) with 95% confidence intervals (CI). The quality and heterogeneity of the included studies were also evaluated carefully.

RESULTS

This systematic review and meta-analysis included 13 retrospective studies with a total of 1294 patients. The incidence of programmed cell death-ligand 1 (PD-L1) expression in PPLELC varied from 63.3% to 75.8%. Positive PD-L1 expression was more likely to be found in patients under 60 years old (OR = 2.16, 95%CI: 1.19-3.89, P = 0.01) and was associated with worse disease-free survival (DFS) compared with negative PD-L1 expression (HR = 2.99, 95%CI: 1.23-7.28, P = 0.02). The pooled results showed that stage was the prognostic factor for both overall survival (OS) and DFS. Moreover, a significantly better outcome of PPLELC was observed in men (HR = 0.56, 95%CI: 0.33-0.95, P = 0.03) and patients who received radiation (HR = 0.46, 95%CI: 0.22-0.96, P = 0.04).

CONCLUSION

PD-L1 expression was high in PPLELC patients. It was significantly associated with age under 60 and the unfavorable DFS. Stage and gender could be the prognostic factor for OS. Radiation could be the effective therapy for PPLELC.

Pembrolizumab plus axitinib combination and the paradigm change in the treatment of advanced renal cell carcinoma

Sequential administration of single targeted agents has been challenged as the dominant treatment paradigm in patients with metastatic renal cell carcinoma by improved outcomes obtained with combination regimens based on immune checkpoint inhibitors. Most patients treated with sequential monotherapy eventually develop drug resistance and succumb to progressive disease, leading to the search for therapies that would overcome drug resistance and result in a more durable treatment response. Improved outcomes have been demonstrated in Phase III trials in comparison with sunitinib for the combinations of axitinib plus pembrolizumab, axitinib plus avelumab, bevacizumab plus atezolizumab and ipilimumab plus nivolumab. A statistically significant improvement of both progression-free and overall survival has been demonstrated for the axitinib plus pembrolizumab combination.

Predictive Biomarkers of Response to Immunotherapy in Metastatic Renal Cell Cancer

Introduction

In the last decades, the therapeutic decision-making approach to metastatic renal cell cancer (mRCC) has dramatically changed thanks to the introduction in the treatment scenario of, first, anti-angiogenic agents and, afterward, immune-checkpoint inhibitors (ICIs). Immunotherapy is now the standard of care in pretreated mRCC patients and has recently entered even the first line setting. Nevertheless, in mRCC as well as in other tumor settings, a durable and clinically meaningful benefit from treatment with ICIs is not obtained for all patients treated. Therefore, the necessity to identify and validate predictive biomarkers of response to immunotherapy has emerged, in order to design the optimal treatment strategy for mRCC patients.

Discussion

In this review, we present and discuss the most promising predictive biomarkers of response to ICIs in mRCC with the recent data available. In details, the first marker that was investigated is the immunohistochemical expression of programmed death receptor ligand 1 (PD-L1), showing a negative prognostic role in mRCC, but the debate about its potential predictive value is still open. Additionally, the high heterogeneity in PD-L1 determination methods adds complexity to this issue. Second, the tumor mutational or neoantigen burden is an emerging biomarker of increased response to immunotherapy, hypothesizing that the higher the TMB, the higher is the production of neoantigens, and thus the stimulation of anti-tumor immune response, even though controversial results have been obtained. Third, the tumor microenvironment, namely the different populations of the immune infiltrate, plays a key role in tumor progression and in the response to immunotherapy. Finally, several studies have collected evidence on the potential association of the occurrence of immune-related adverse events (irAEs) with the benefit from ICIs, first in non-small cell lung cancer (NSCLC) and melanoma, and recently even in mRCC.

Conclusion

Several promising biomarkers of response to immunotherapy with ICIs have been identified, though without conclusive results upon their potential predictive value in mRCC. Therefore, the results of the exploratory analyses of the recently presented first-line trials and hopefully of future prospective, biomarker-driven studies could provide useful tools to be applied in the everyday clinical practice.

Combinations in the first-line treatment of patients with advanced/metastatic renal cell cancer: regulatory aspects

The therapeutic landscape in the treatment of advanced/metastatic renal cell cancer has evolved over the last 2 years with the advent of immune checkpoint inhibitors. In 2018 and 2019, marketing authorisations valid throughout the European Union were issued for nivolumab and ipilimumab dual checkpoint inhibition and pembrolizumab or avelumab in combination with the tyrosine kinase inhibitor axitinib. These applications presented numerous regulatory challenges.In this paper, we summarise the main regulatory considerations, originating from the assessment of the dossiers submitted from the applicants for the three combinations. The regulatory issues are grouped in four sections: clinical pharmacology, efficacy, biomarkers and safety. In each section, we describe the issues raised during the regulatory evaluation performed by the Committee for Medicinal Products for Human Use (CHMP) assessors. The CHMP assessments determine whether the medicines concerned meet the necessary quality, safety and efficacy requirements, and whether the benefit-risk balance is positive.In summary, although the overall benefit-risk was considered positive for the three combinations, the immaturity of the outcome data and the absence of long-term safety data remain issues to be addressed. Postauthorisation efficacy studies have been required to confirm the effects of the new combinations.

Association between PD-L1 Expression and the Prognosis and Clinicopathologic Features of Renal Cell Carcinoma: A Systematic Review and Meta-Analysis

The expression of programmed cell death-ligand 1 (PD-L1) and its correlation with the prognosis and clinicopathologic features of renal cell carcinoma (RCC) remain controversial to date. Concerning this issue, we had conducted a meta-analysis of relevant studies searched in the Web of Science, PubMed, EMBASE, and Cochrane Library databases. The Newcastle-Ottawa quality assessment scale was applied to assess the quality of the included studies. The hazard ratio (HR) and its corresponding 95% confidence intervals (CIs) were collected by Stata 12.0 and used for the results of overall survival (OS) and disease-free survival (DFS). A total of 1,644 patients in 8 studies were included in this meta-analysis. Results showed that PD-L1 expression significantly correlated with OS (HR = 1.98, 95% CI: 1.22-3.22, Z = 2.77, p = 0.006) and DFS (HR = 3.70, 95% CI: 2.07-6.62, Z = 4.40, p = 0.0001) in ccRCC. Subgroup analysis indicated that PD-L1 expression significantly correlated with the lymph-gland transfer ratio (HR = 2.45, 95% CI: 1.02-5.92, Z = 1.99, p = 0.05) and tumor necrosis (HR = 6.05, 95% CI: 3.78-9.67, Z = 7.51, p < 0.00001). This meta-analysis suggests that PD-L1 expression is a valuable prognostic tool for patients with ccRCC. Subgroup analyses demonstrated that it was helpful for screening patients with RCC who need anti-PD-1/PD-L1 treatment and support them to benefit from such immune-targeted therapy.

Programmed Death Ligand 1: A Poor Prognostic Marker in Endometrial Carcinoma

Endometrial carcinoma is the only gynaecologic malignancy with a raising incidence and mortality, posing a major health concern worldwide. The upregulation of programmed death ligand 1 (PD-L1) on tumour cells causes T-cell suppression, which impedes antitumour immunity, promotes immune cell evasion and enhances tumour survival. The aim of this study was to evaluate PD-L1 expression in endometrial carcinoma and to correlate it with survival rate. A total of 59 cases of endometrial carcinoma were evaluated. Thirty-two cases of non-neoplastic endometrial tissue were included as control. PD-L1 immunohistochemistry was performed on all cases. PD-L1 expression was evaluated on tumour cells and immune cells. PD-L1 was positive in 62.7% (37/59) and 28.8% (17/59) of immune cells and tumour cells, respectively. PD-L1 expression in immune cells was significantly higher in endometrial carcinoma than in non-neoplastic endometrium (p < 0.001). Among the patients with endometrial carcinoma, PD-L1 expression in tumour cells was significantly higher in patients who died (10/15, 66.7%) compared to those who survived (7/44, 15.9%) (p < 0.001). It is noteworthy to point out that the expression of PD-L1 in tumour cells was significantly associated with a poor survival. This suggests that immunomodulation using PD-L1 inhibitors may be useful in advanced endometrial carcinoma.

Prognostic significance of proteomics and multi-omics studies in renal carcinoma

INTRODUCTION

Renal carcinoma, and in particular its most common variant, the clear cell subtype, is often diagnosed incidentally through abdominal imaging and frequently, the tumor is discovered at an early stage. However, 20% to 40% of patients undergoing nephrectomy for clinically localized renal cancer, even after accurate histological and clinical classification, will develop metastasis or recurrence, justifying the associated mortality rate. Therefore, even if renal carcinoma is not among the most frequent nor deadly cancers, a better prognostication is needed.

AREAS COVERED

Recently proteomics or other omics combinations have been applied to both cancer tissues, on the neoplasia itself and surrounding microenvironment, cultured cells, and biological fluids (so-called liquid biopsy) generating a list of prognostic molecular tools that will be reviewed in the present paper.

EXPERT OPINION

Although promising, none of the approaches listed above has been yet translated in clinics. This is likely due to the peculiar genetic and phenotypic heterogeneity of this cancer, which makes nearly each tumor different from all the others. Attempts to overcome this issue will be also revised. In particular, we will discuss how the application of omics-integrated approaches could provide the determinants of response to the different targeted drugs.

Comparative analysis of programmed cell death ligand 1 assays in renal cell carcinoma

AIMS

The importance of programmed cell death ligand 1 (PD-L1) expression has emerged in clinical trials of PD-L1 target therapy in renal cell carcinoma (RCC). This study compares PD-L1 assays in RCC.

METHODS AND RESULTS

Two US Food and Drug Administration-approved PD-L1 assays (22C3 and SP142) and one research-use only antibody (E1L3N) were used in a retrospective cohort of 591 patients with RCC. PD-L1 positivity on tumour cells (TCs) and immune cells (ICs) and combined positive score (CPS) were evaluated. With the 22C3, SP142 and E1L3N assays, positive PD-L1 expression on TCs ≥1% was observed in 24 (4.1%), 12 (2.0%) and 16 (2.7%) cases and on ICs ≥1% was observed in 132 (22.3%), 120 (20.3%) and 65 (11.0%) cases, respectively. PD-L1 expression scores among the three assays showed moderate-high positive correlation (ρ = 0.599-0.835, P < 0.001). Assays appeared similar, although staining in ICs was comparatively less frequent with E1L3N. 22C3 showed frequent positivity in TCs. PD-L1 expression on TCs was associated with papillary type 2 RCC (P < 0.001). IC infiltration and PD-L1 expression on ICs were predominantly found in clear cell and papillary type 1 RCC (P < 0.05).

CONCLUSIONS

Programmed death 1 (PD-1)/PD-L1 target therapy may be beneficial for patients with papillary type 2 RCC, even if they are categorised as a heterogeneous group. PD-L1 assays should be carefully selected, and accurate histological subtyping of RCC is needed prior to decisions on PD-L1 testing, because of the different PD-L1 expression observed among varying RCC subtypes.

Galectin-9 expression as a poor prognostic factor in patients with renal cell carcinoma

Recently, the effectiveness of anti-programmed death 1 (PD-1) antibody therapy in the treatment of renal cell carcinoma (RCC) has been established. Nevertheless, efficacy has been reported to be limited to only 10-30% of patients. To develop more effective immunotherapy for RCC, we analyzed the immunological characteristics in RCC tissues by immunohistochemistry (IHC). We prepared a tissue microarray that consisted of tumor tissue sections (1 mm in diameter) from 83 RCC patients in Kanagawa Cancer Center between 2006 and 2015. IHC analysis was performed with antibodies specific to immune-related (CD8 and Foxp3) and immune checkpoint (programmed death ligand 1 (PD-L1) and 2 (PD-L2), B7-H4 and galectin-9) molecules. The numbers and proportions of positively stained tumor cells or immune cells were determined in each section. From multivariate analysis of all 83 patients, higher galectin-9 expression was detected as a factor associated with worse overall survival (OS) (P = 0.029) and that higher stage and higher B7-H4 expression were associated with worse progression-free survival (PFS) (P < 0.001 and P = 0.021, respectively). Similarly, in multivariate analysis of 69 patients with clear cell RCC, though not statistically significant, there was a trend for association between higher galectin-9 expression and worse OS (P = 0.067), while higher stage was associated with worse PFS (P < 0.001). This study suggests that higher galectin-9 expression is an independent adverse prognostic factor of OS in RCC patients. Therefore, to develop more effective personalized immunotherapy to treat RCC, it may be important to target not only PD-1/PD-L1, but also other immune checkpoint molecules such as galectin-9.

Programmed death ligand 1/indoleamine 2,3-dioxygenase 1 expression and tumor-infiltrating lymphocyte status in renal cell carcinoma with sarcomatoid changes and rhabdoid features

Renal cell carcinoma (RCC) with sarcomatoid changes and rhabdoid features has shown poor outcomes. Several immune checkpoint inhibitors including programmed cell death protein 1 (PD-1)/programmed death ligand-1 (PD-L1) inhibitors have been approved for the treatment of RCC. Combination therapy using PD-1/PD-L1 and indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors has also been used to treat various malignancies. However, little is known about IDO1 expression and therapeutic effects of the IDO1 inhibitor in RCC. Herein, we retrospectively analyzed the expression of PD-L1/IDO1 and examined its relationship with tumor-infiltrating lymphocyte (TIL) status and prognostic effect. We investigated the PD-L1, IDO1, CD3⁺, CD4⁺, and CD8⁺ immunoexpression status in 60 cases of sarcomatoid/rhabdoid RCC. The PD-L1 and IDO1 results were defined by the tumor proportion score. For the evaluation of TIL status, we counted the number of lymphocytes located in the tumor and averaged the numbers over five high-power fields for each case. The results revealed PD-L1 and IDO1 expression was observed more frequently in the sarcomatoid/rhabdoid component than in the nonsarcomatoid/nonrhabdoid component. The correlation between PD-L1 and IDO1 expression was significant (P = 0.0076). PD-L1 expression and coexpression of PD-L1 and IDO1 were correlated with a high density of CD3⁺, CD4⁺, and CD8⁺ T cells. There was no significant difference in overall survival among the patients with PD-L1 and/or IDO1 expression, but PD-L1 expression and coexpression were related to poor progression-free survival. Our results suggest that combination therapy using the PD-1/PD-L1 inhibitor and IDO1 inhibitor may be effective for treating sarcomatoid/rhabdoid RCC.

Clinicopathological implications of the expression of vascular endothelial growth factor and programmed death ligand 1 in clear-cell renal cell carcinoma

Combined anti-VEGF/anti-programmed death ligand 1 (PD-L1) therapy synergistically improves treatment outcomes in advanced renal cell carcinoma (RCC) compared with anti-PD-L1 or anti-vascular endothelial growth factor (VEGF) monotherapy. Here, we analyzed the expression of VEGF and PD-L1 (SP142) in a retrospective cohort of 513 patients with clear-cell (cc) RCC. PD-L1 expression on tumor cells (TCs) and immune cells (ICs) was evaluated by immunohistochemistry (IHC) with a positive threshold value of ≥1%. Positive staining for PD-L1 on ICs and TCs was found in 115 (22.4%) and 7 (1.4%) cases, respectively. Moderate or strong staining for VEGF on TCs was found in 217 (42.3%) patients. PD-L1 expression on ICs and TCs was positively associated with VEGF expression on TCs. Both VEGF and PD-L1 (IC) positivity (VEGF/PD-L1 [IC]: +/+) was observed in 65 (12.7%) cases. Patients in this subgroup exhibited more aggressive clinicopathologic features, including older age, higher World Health Organization/International Society of Urological Pathology (ISUP) grade, angiolymphatic invasion, tumor necrosis, and sarcomatoid differentiation (P < 0.05). Kaplan-Meier analysis indicated that expression of VEGF and PD-L1 on ICs was positively correlated with tumor recurrence (P < 0.001), whereas expression of PD-L1 on TCs was not (P = 0.554). Tumors with positivity for both antibodies (VEGF/PD-L1 [IC]: +/+) exhibited the worst recurrence-free survival (P < 0.001), and double positivity independently predicted tumor recurrence in ccRCC. The present study provides comprehensive and basic information about VEGF and PD-L1 expression for new combined therapy in primary ccRCC.

A pooled analysis of the prognostic value of PD-L1 in melanoma: evidence from 1062 patients

Background

Programmed death-ligand 1 (PD-L1) was the first identified ligand of programmed death-1 (PD-1). PD-1/PD-L1 interactions inhibit T cell-mediated immune responses, limit cytokine production, and promote tumor immune escape. Recently, many studies have investigated the prognostic value of PD-L1 expression in patients with melanoma. However, the results of these analyses remain a subject of debate. We have therefore carried out a meta-analysis to identify the prognostic role of PD-L1 in melanoma.

Methods

A thorough medical literature search was performed in the databases PubMed, Web of Science, and Embase until October 2019. The pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated to evaluate the correlation between PD-L1 overexpression and prognosis. Publication bias was evaluated using Begg’s test and Egger’s test.

Results

Thirteen articles with 1062 enrolled patients were included in this meta-analysis. High PD-L1 expression did not correlate with overall survival (OS) (HR = 0.93, 95% CI 0.57–1.52, P = 0.781) or progression-free survival (PFS) (HR = 0.82, 95% CI 0.43–1.54, P = 0.535). However, PD-L1 overexpression correlated with the absence of lymph node (LN) metastasis (OR = 0.46, 95% CI 0.22–0.95, P = 0.036). Further, there was no significant relationship between PD-L1 expression and sex (OR = 1.29, 95% CI 0.90–1.84, P = 0.159), age (OR = 0.90, 95% CI 0.51–1.57, P = 0.708), or Eastern Cooperative Oncology Group Performance Status (OR = 0.55, 95% CI 0.06–4.83, P = 0.592).

Conclusions

This meta-analysis suggested that PD-L1 expression did not predict an inferior prognosis in patients with melanoma. However, high PD-L1 expression was associated with absence of LN metastasis in such patients.

Determination of the Expression of PD-L1 in the Morphologic Spectrum of Renal Cell Carcinoma

Immunotherapy is reportedly an effective form of therapy for some advanced cancers such as lung adenocarcinoma, malignant melanoma and colorectal adenocarcinoma. In renal cell carcinoma (RCC), the role of immunotherapy is under investigation. Programmed Death-Ligand 1 (PD-L1) is a molecule expressed on the surface of certain tumor cells and binds to the Programmed cell death protein 1 (PD-1) on cytotoxic T-cells, an interaction that inhibits the antitumor immune response. The aim of this study is to evaluate PD-L1 expression in the morphologic spectrum of RCC. A total of 172 cases of RCC comprising all types were studied and the PD-L1 was correlated with immune response for CD4 and CD8. Positive membranous staining for PD-L1 was seen in 59 (34%) of the 172 samples. The positive cases were HLRCC (31/53), Type 1 Papillary RCC (10/31), Chromophobe (7/20), Hybrid (3/9), TFE-3 related cancer (3/8), Undifferentiated (3/5), and TFEB tumors (2/2). Clear cell carcinomas, Oncocytomas and SDHB deficient-RCC didn't show any expression of PD-L1; (0/34;0/7;0/3). Our results demonstrated that aggressive forms of RCC such as HLRCC have high expression of PD-L1, in contrast to clear cell renal carcinomas. Our findings support a possible role of anti-PD-L1/PD-1 immunotherapies in the treatment of PD-L1-positive RCC.

Current State of Systemic Therapies for Advanced Renal Cell Carcinoma

PURPOSE OF REVIEW

Due to the rapidly changing field of kidney cancer therapeutics, addressing the state of the art systemic therapy regimens, and sequencing with cytoreductive nephrectomy are the primary focus of this review. We will also discuss the role of biomarkers and novel therapeutic targets in the management of renal cell carcinoma.

RECENT FINDINGS

The management of metastatic renal cell cancer has undergone a paradigm shift with immune checkpoint inhibitors being used in the frontline setting. Over the last 4 years, programmed cell death-1 (PD-1) inhibitors as well as programmed cell death ligand-1 inhibitors have become available in various combinations with cytotoxic T lymphocyte-associated protein-4 (CTLA-4) inhibitors and tyrosine kinase inhibitors (TKIs). These drugs have improved outcomes in patients with renal cell cancer and more work is being done to refine these targets as well as discover newer ones. Despite the availability of several new treatment options, some questions that still need to be addressed in the management of kidney cancer include the sequencing of treatment options, treatment of patients who progress on immune checkpoint inhibitors, and role of biomarkers to ascertain the best treatment options to minimize costs and improve outcomes.

Checkpoint inhibitor immunotherapy in kidney cancer

Kidney cancer has unique features that make this malignancy attractive for therapeutic approaches that target components of the immune system. Immune checkpoint inhibition is a well-established part of kidney cancer treatment, and rapid advances continue to be made in this field. Initial preclinical studies that elucidated the biology of the programmed cell death 1 (PD-1), programmed cell death 1 ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) immune checkpoints led to a series of clinical trials that resulted in regulatory approval of nivolumab and the combination of ipilimumab plus nivolumab for the treatment of advanced renal cell carcinoma. Subsequent data led to approvals of combination strategies of immune checkpoint inhibition plus agents that target the vascular endothelial growth factor receptor and a shift in the current standard of renal cell carcinoma care. However, controversies remain regarding the optimal therapy selection and treatment strategy for individual patients, which might be eventually overcome by current intensive efforts in biomarker research. That work includes evaluation of tumour cell PD-L1 expression, gene expression signatures, CD8⁺ T cell density and others. In the future, further advances in the understanding of immune checkpoint biology might reveal new therapeutic targets beyond PD-1, PD-L1 and CTLA-4, as well as new combination approaches.

Targeting the Immune system and Epigenetic Landscape of Urological Tumors

In the last years, we have witnessed remarkable advances in targeted therapies for cancer patients. There is a growing effort to either replace or reduce the dose of unspecific, systemic (chemo)therapies, given the associated short- and long-term side effects, by introducing more specific targeted therapies as single or combination agents. Due to the well-known implications of the immune system and epigenetic landscape in modulating cancer development, both have been explored as potential targets in several malignancies, including those affecting the genitourinary tract. As the immune system function is also epigenetically regulated, there is rationale for combining both strategies. However, this is still rather underexplored, namely in urological tumors. We aim to briefly review the use of immune therapies in prostate, kidney, bladder, and testicular cancer, and further describe studies providing supporting evidence on their combination with epigenetic-based therapies.

A prospective, open-label, interventional study protocol to evaluate treatment efficacy of nivolumab based on serum-soluble PD-L1 concentration for patients with metastatic and unresectable renal cell carcinoma

INTRODUCTION

Nivolumab has been proven to prolong overall survival as a second-line therapy for patients with advanced renal cell carcinoma (RCC) in a phase III clinical trial. However, versatile biomarkers have not been established to predict the efficacy of nivolumab against target disease.

METHODS AND ANALYSIS

After registration, screening test and serum-soluble programmed cell death 1-ligand 1 (sPD-L1) measurement will be performed by using the ELISA; patients will be grouped into high sPD-L1 or low sPD-L1 groups. Nivolumab (240 mg every 2 weeks by intravenous drip infusion) will be administered to each participant. For this prospective study, statistical power calculation indicated that 48 participants with metastatic or unresectable RCC are needed to assess the efficacy of this method. The participants must be at the age of at least 20 years at the time of informed consent and require second-line therapy after failure of first-line therapy or discontinuation due to adverse effects. All data will be collected in our institution. The primary endpoint is progression-free survival, and secondary endpoints are overall survival and objective response rate. In this protocol, we will examine sPD-L1 as a promising predictive marker.

ETHICS AND DISSEMINATION

This protocol was approved by the Kobe University Clinical Research Ethical Committee (C180067). Findings of this study will be widely disseminated through conference presentations, reports, factsheets and academic publications; further generalisation will also be discussed.

TRIAL REGISTRATION NUMBER

UMIN000027873.

Towards individualized therapy for metastatic renal cell carcinoma

Over the past decade, the treatment landscape for patients with metastatic renal cell carcinoma (RCC) has evolved dramatically. The therapeutic options available have expanded and now include immune-checkpoint inhibitors, novel targeted agents and combination strategies, and thus optimal patient selection and treatment sequencing are increasingly pertinent for optimizing clinical outcomes. A better understanding of the underlying biology of the tumour and its microenvironment continues to drive the inception of new diagnostic and therapeutic approaches. Furthermore, many biomarkers robustly associated with treatment and disease-specific outcomes have been identified, and their integration into clinical decision-making for patients with advanced-stage disease will soon become a reality. Herein, we review relevant aspects of the molecular biology of metastatic RCC, with an emphasis on predictive and prognostic biomarkers, and suggest tailored algorithms to individualize and guide treatment approaches for specific subgroups of patients.

Prognostic Value of Programmed Cell Death Ligand-1 Expression in Nasopharyngeal Carcinoma: A Meta-Analysis of 1,315 Patients

Background: The prognostic value of programmed cell death ligand-1 (PD-L1) in patients with nasopharyngeal carcinoma (NPC) remains controversial. Therefore, we conducted this meta-analysis to understand the role of PD-L1 in NPC.

Method: We searched PubMed, Embase, Web of Science, and Cochrane Library up to April 2019. We determined the pooled hazard ratio (HR) and 95% confidence intervals (CIs) to assess the relationship between PD-L1 and various survival outcomes. Begg's funnel plot was used to assess any publication bias.

Results: Eleven studies involving 1,315 patients were included in this meta-analysis. For overall survival (OS), the HR was 1.48 and 95% CI was 1.00–2.18 (p = 0.049). For disease-free survival (DFS), the HR was 1.51 and 95% CI was 0.85–2.69 (p = 0.162). For distant metastasis-free survival (DMFS), the HR was 1.75 and 95% CI was 0.64–4.79 (p = 0.277). For local recurrence-free survival (LRFS), the HR was 0.67 and 95% CI was 0.06–8.16 (p = 0.756). The results of prognosis of PD-L1 and OS were more significant after sensitivity analysis. The pooled odds ratio indicated that PD-L1 expression was not associated with T stage, N stage, M stage, overall stage, sex, age, smoking, or alcohol intake. No publication bias was found.

Conclusion: Our meta-analysis showed that PD-L1 overexpression in NPC was associated with a poor OS and may be useful as a novel prognostic factor for NPC.

Avelumab monotherapy as first-line or second-line treatment in patients with metastatic renal cell carcinoma: phase Ib results from the JAVELIN Solid Tumor trial

BACKGROUND

Antibodies targeting programmed death-1 (PD-1) or programmed death-ligand 1 (PD-L1) have shown clinical activity in the treatment of metastatic renal cell carcinoma (mRCC). This phase Ib cohort of the JAVELIN Solid Tumor trial assessed the efficacy and safety of avelumab (anti-PD-L1) monotherapy in patients with mRCC as either first-line (1 L) or second-line (2 L) treatment.

METHODS

Patients with mRCC with a clear-cell component who were treatment naive (1 L subgroup) or had disease progression after one prior line of therapy (2 L subgroup) received avelumab 10 mg/kg intravenous infusion every 2 weeks. Endpoints included confirmed best overall response, duration of response (DOR), progression-free survival (PFS), overall survival (OS), PD-L1 expression, and safety.

RESULTS

A total of 62 patients were enrolled in the 1 L subgroup, and 20 patients were enrolled in the 2 L subgroup. In the 1 L and 2 L subgroups, confirmed objective response rates were 16.1 and 10.0%, median DOR was 9.9 months (95% confidence interval [CI], 2.8-not evaluable) and not evaluable (95% CI, 6.9-not evaluable), median PFS was 8.3 months (95% CI, 5.5-9.5) and 5.6 months (95% CI, 2.3-9.6), and median OS was not evaluable (95% CI, not evaluable) and 16.9 months (95% CI, 8.3-not evaluable), respectively. Treatment-related adverse events (TRAEs) of any grade occurred in 51 patients in the 1 L subgroup (82.3%) and 14 patients in the 2 L subgroup (70.0%). Grade ≥ 3 TRAEs occurred in eight patients in the 1 L subgroup (12.9%) and one patient in the 2 L subgroup (5.0%). No treatment-related deaths occurred.

CONCLUSION

Avelumab showed clinical activity and a manageable safety profile in both the 1 L and 2 L treatment setting in patients with mRCC. These data support the use of avelumab in combination with other agents in mRCC.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01772004 ; registered 21 January, 2013.

Prognostic value of PD-L1 expression for surgically treated localized renal cell carcinoma: implications for risk stratification and adjuvant therapies

Background:

We aimed to evaluate the prognostic role of programmed-death receptor ligand (PD-L1) in a multinational cohort of patients with localized renal cell carcinoma (RCC).

Methods:

Formalin-fixed paraffin-embedded blocks of 1017 patients from the Latin American Renal Cancer Group were analyzed. Tissue microarrays were immunostained for PD-L1 using a commercially available monoclonal antibody. Expression of PD-L1 in ⩾5% tumor cells was considered positive. PD-1 expression in immune cells was also assessed. All cases were reviewed twice based on antibody expression and compared with a positive control. Cox proportional hazard regression models were used to identify predictors of recurrence-free survival (RFS) and overall survival (OS).

Results:

A total of 738 cases with complete follow up met criteria. Median age was 57 [interquartile range (IQR): 49–64] years, and median follow up was 34 (IQR: 15–62.9) months. Median tumor size was 5 cm (IQR: 3.0–7.5 cm). Approximately 8.2% and 7.6% of tumors were PD-L1 and programmed cell-death 1 (PD-1) positive, respectively. PD-L1 and PD-1 positivity were significantly associated with higher tumor stage (both p < 0.001), and presence of tumor necrosis and lymphovascular multivariable analyses; PD-L1 positivity was found as a predictor of worse RFS [hazard ratio (HR) = 2.08, p = 0.05] and OS (HR = 2.61, p = 0.02).

Conclusions:

PD-L1 positivity was significantly associated with worse outcomes for patients with localized RCC at intermediate follow up. This marker may help stratify patients for stricter surveillance after surgical treatment and provide a basis for checkpoint-inhibitor therapy in the adjuvant setting.

Immune checkpoint inhibition for the treatment of renal cell carcinoma

Introduction: The systemic therapy in metastatic renal cell carcinoma (mRCC) is moving from tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors to immune checkpoint inhibitors and its combination with TKIs.Areas covered: This review provides a general overview using immune checkpoint inhibition for the treatment of RCC. Clinical results from conducted and ongoing clinical trials are summarized and checkpoint inhibition is reviewed in the context to other available systemic therapies such as TKIs for mRCC based on the different International Metastastic RCC Database Consortium (IMCD) risk groups. Furthermore, prospects for the use of predictive biomarkers in the decision-making process of chosen therapy will be given.Expert opinion: Using checkpoint inhibition in mRCC has demonstrated a superior efficacy for patients with IMDC intermediate and poor risk for ipilimumab combined with nivolumab. Furthermore, therapeutic regimes with tyrosine kinase inhibition plus immune checkpoint-inhibition were recently presented and demonstrated superiority in all risk groups for axitinib plus pembrolizumab in overall survival and progression-free survival (PFS) and axitinib plus avelumab in PFS compared to sunitinib monotherapy. Novel biomarkers of response to further optimize therapeutic selection and patient outcomes are ongoing medical objectives.

Vascular endothelial growth factor and programmed death-1 pathway inhibitors in renal cell carcinoma

Advanced renal cell carcinoma has historically carried a poor prognosis with very limited treatment options. However, in recent years, the treatment landscape has changed drastically, with many new therapeutic options and improved survival for patients. Novel treatments consist of molecularly targeted agents against the vascular endothelial growth factor (VEGF) pathway as well as the immune checkpoint inhibitors, which stimulate an antitumor immune response. Recent strategy has focused on the development of combination therapy with the use of VEGF inhibitors and immune checkpoint inhibitors in the first-line setting. As more treatments are approved and the options for therapy expand further, there is a growing need for predictive biomarkers to personalize treatment choices for individual patients. Prospective clinical trials comparing the sequencing of treatments are needed to help determine the best therapeutic approach.

The Changing Therapeutic Landscape of Metastatic Renal Cancer

The practising clinician treating a patient with metastatic clear cell renal cell carcinoma (CCRCC) faces a difficult task of choosing the most appropriate therapeutic regimen in a rapidly developing field with recommendations derived from clinical trials. NCCN guidelines for kidney cancer initiated a major shift in risk categorization and now include emerging treatments in the neoadjuvant setting. Updates of European Association of Urology clinical guidelines also include immune checkpoint inhibition as the first-line treatment. Randomized trials have demonstrated a survival benefit for ipilimumab and nivolumab combination in the intermediate and poor-risk group, while pembrolizumab plus axitinib combination is recommended not only for unfavorable disease but also for patients who fit the favorable risk category. Currently vascular endothelial growth factor (VEGF) targeted therapy based on tyrosine kinase inhibitors (TKI), sunitinib and pazopanib is the alternative regimen for patients who cannot tolerate immune checkpoint inhibitors (ICI). Cabozantinib remains a valid alternative option for the intermediate and high-risk group. For previously treated patients with TKI with progression, nivolumab, cabozantinib, axitinib, or the combination of ipilimumab and nivolumab appear the most plausible alternatives. For patients previously treated with ICI, any VEGF-targeted therapy, not previously used in combination with ICI therapy, seems to be a valid option, although the strength of this recommendation is weak. The indication for cytoreductive nephrectomy (CN) is also changing. Neoadjuvant systemic therapy does not add perioperative morbidity and can help identify non-responders, avoiding unnecessary surgery. However, the role of CN should be investigated under the light of new immunotherapeutic interventions. Also, markers of response to ICI need to be identified before the optimal selection of therapy could be determined for a particular patient.

Prognostic implications of soluble programmed death-ligand 1 and its dynamics during chemotherapy in unresectable pancreatic cancer

In pancreatic cancer, acquiring a sufficient amount of tumor tissue is an obstacle. The soluble form of PD-L1 (sPD-L1) may have immunosuppressive activity. Here, we evaluated the prognostic implications of sPD-L1 in unresectable pancreatic cancer. We prospectively enrolled 60 patients treated with first-line FOLFIRINOX chemotherapy. We collected blood samples at diagnosis, first response assessment and disease progression. Serum sPD-L1 levels were measured using enzyme-linked immunosorbent assays. The median sPD-L1 level was 1.7 ng/mL (range, 0.4-5.7 ng/mL). Patients with low sPD-L1 level (<4.6 ng/mL) at diagnosis showed better overall survival (OS) than those with high sPD-L1 level (P = 0.015). Multivariate analysis identified sPD-L1 and the neutrophil-to-lymphocyte ratio as independent prognostic factors for OS. During chemotherapy, more patients achieved complete response (CR)/partial response (PR) as their best response when sPD-L1 was decreased at the first response assessment (P = 0.038). In the patients who achieved CR/PR as their best response, sPD-L1 was significantly higher at the time of disease progression than at the first response assessment (P = 0.025). In conclusion, the sPD-L1 level at diagnosis exhibits a prognostic value in pancreatic cancer. Furthermore, sPD-L1 dynamics correlate with disease course and could be used to understand various changes in the tumor microenvironment during chemotherapy.

PD-L1 detection using 89Zr-atezolizumab immuno-PET in renal cell carcinoma tumorgrafts from a patient with favorable nivolumab response

Background

Programmed death-ligand 1 (PD-L1) expression in metastatic renal cell carcinoma (RCC) correlates with a worse prognosis, but whether it also predicts responsiveness to anti-PD-1/PD-L1 therapy remains unclear. Most studies of PD-L1 are limited by evaluation in primary rather than metastatic sites, and in biopsy samples, which may not be representative. These limitations may be overcome with immuno–positron emission tomography (iPET), an emerging tool allowing the detection of cell surface proteins with radiolabeled antibodies. Here, we report iPET studies of PD-L1 in a preclinical tumorgraft model of clear cell RCC (ccRCC) from a patient who had a favorable response to anti-PD-1 therapy.

Case presentation

A 49-year-old man underwent a cytoreductive nephrectomy in 2017 of a right kidney tumor invading into the adrenal gland that was metastatic to the lungs and a rib. Histological analyses revealed a ccRCC of ISUP grade 4 with extensive sarcomatoid features. IMDC risk group was poor. Within two hours of surgery, a tumor sample was implanted orthotopically into NOD/SCID mice. Consistent with an aggressive tumor, a renal mass was detected 18 days post-implantation. Histologically, the tumorgraft showed sarcomatoid differentiation and high levels of PD-L1, similar to the patient’s tumor. PD-L1 was evaluated in subsequently transplanted mice using iPET and the results were compared to control mice implanted with a PD-L1-negative tumor. We labeled atezolizumab, an anti-PD-L1 antibody with a mutant Fc, with zirconium-89. iPET revealed significantly higher ⁸⁹Zr-atezolizumab uptake in index than control tumorgrafts. The patient was treated with high-dose IL2 initially, and subsequently with pazopanib, with rapidly progressive disease, but had a durable response with nivolumab.

Conclusions

To our knowledge, this is the first report of non-invasive detection of PD-L1 in renal cancer using molecular imaging. This study supports clinical evaluation of iPET to identify RCC patients with tumors deploying the PD-L1 checkpoint pathway who may be most likely to benefit from PD-1/PD-L1 disrupting drugs.

Expression of PD-1 and CTLA-4 Are Negative Prognostic Markers in Renal Cell Carcinoma

Immuno-oncological therapy with checkpoint inhibition (CI) has become a new standard treatment in metastatic renal cell carcinoma (RCC), but the prognostic value of the expression of CI therapy target molecules is still controversial. 342 unselected consecutive RCC tumor samples were analyzed regarding their PD-1, PD-L1, and CTLA-4 expression by immunohistochemistry (IHC). The prognostic values for cancer-specific survival (CSS) and overall survival (OS) were analyzed for those not exposed to CI therapy. The expression of PD-1 in tumor-infiltrating mononuclear cells (TIMC) and PD-L1 in tumor cells was detected in 9.4% and 12.3%, respectively (Immune reactive score (IRS) > 0). Furthermore, PD-L1 expression in TIMC (IRS > 0) and CTLA-4 expression in TIMC (>1% positive cells) was detected in 4.8% and 6.3%. PD-1 expression and CTLA-4 expression were significantly associated with a worse OS and CSS in log rank survival analysis and univariate Cox regression analysis. CTLA-4 expression is a prognostic marker that is independently associated with a worse outcome in multivariate Cox regression analysis in the whole cohort (OS: p = 0.013; CSS: p = 0.048) as well as in a non-metastatic subgroup analysis (OS: p = 0.028; CSS: p = 0.022). Patients with combined CTLA-4 expression and PD-1-expression are at highest risk in OS and CSS. In RCC patients, PD-1 expression in TIMC and CTLA-4 expression in TIMC are associated with a worse OS and CSS. The combination of PD-1 expression in TIMC and CTLA-4 expression in TIMC might identify high risk patients. This is, to our knowledge, the first description of CTLA-4 expression to be a prognostic marker in RCC.