First-line treatment with sunitinib for type 1 and type 2 locally advanced or metastatic papillary renal cell carcinoma: a phase II study (SUPAP) by the French Genitourinary Group (GETUG)†

Papillary Renal Cell Carcinoma: Outcomes for Patients Receiving First-line Immune-based Combinations or Tyrosine Kinase Inhibitors from the ARON-1 Study

BACKGROUND AND OBJECTIVE

Papillary renal cell carcinoma (pRCC) is the most frequent histological subtype of non-clear cell RCC (nccRCC). Owing to the heterogeneity of nccRCC, patients are often excluded from large phase 3 trials focused on clear cell RCC, so treatment options for nccRCC remain limited. Our aim was to investigate the efficacy of first-line treatment with tyrosine kinase inhibitors (TKIs) or immuno-oncology (IO)-based combinations in patients with pRCC.

METHODS

We performed a multicenter retrospective analysis of real-world data collected for patients with advanced pRCC treated in 40 centers in 12 countries as part of the ARON-1 project (NCT05287464). The primary endpoints were overall survival (OS), progression-free survival (PFS), the overall response rate (ORR), and time to second progression (PFS2). OS, PFS, and PFS2 were estimated using the Kaplan-Meier method and results were compared between the treatment groups using a log-rank test. Univariate and multivariable analyses were carried out using Cox proportional-hazard models.

KEY FINDINGS AND LIMITATIONS

We included 200 patients with metastatic pRCC, of whom 73 were treated with IO-based combinations and 127 with TKIs. Median OS was 22.5 mo in the TKI group 28.8 mo in the IO group (p = 0.081). Median PFS was 6.4 mo in the TKI group and 17.4 mo in the IO group (p < 0.001). The ORR was higher in the IO group than in the TKI group (41% vs 27%; p = 0.037).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Our results show that IO-based combinations have superior efficacy outcomes to TKIs for first-line treatment of metastatic pRCC.

PATIENT SUMMARY

The ARON-1 project collects clinical data for patients with kidney cancer treated in multiple centers worldwide to assess outcomes in the real-world setting. We analyzed data for patients with metastatic kidney cancer of a specific subtype to evaluate the efficacy of different first-line treatments. Patients treated with immune-based combinations had better outcomes than patients treated with tyrosine kinase inhibitors.

Advances in non-clear cell renal cell carcinoma management: From heterogeneous biology to treatment options

Non-clear cell renal cell carcinoma (nccRCC) makes up nearly one quarter of all RCC subtypes, commonly impacts younger patients, and is often metastatic at presentation. Compared to clear-cell RCC (ccRCC), nccRCC typically has a worse prognosis in the metastatic setting, with overall survival durations that are ~10 months shorter. The nccRCC consists of a wide range of different histological subtypes, the majority of which are composed of papillary, chromophobe, renal medullary carcinoma, translocation RCC, collecting duct carcinoma and unclassified RCC. Most clinical trials have either excluded or only included small numbers of patients with nccRCC; owing to the lack of prospective studies focusing on this population, data on response rates and survival outcomes are lacking. NccRCC treatment is a nascent field with various therapeutic modalities and combinations under investigation, often based on data extrapolated from therapeutic studies in ccRCC. We herein review the use and outcomes of cytotoxic chemotherapy, various combination modalities of tyrosine kinase inhibitors and immune checkpoint inhibitors, and targeted agents. We discuss active ongoing clinical trials for patients with nccRCC and future directions in the treatment of this rare disease. Historically, treatment for nccRCC has been adopted from the standard of care for patients with ccRCC, although these treatments are less effective in the nccRCC population. As we begin to understand the underlying biology of these tumors, clinical trials have been able to slowly accrue and include more patients with various subtypes of nccRCC. There remains much room for improvement in this area of need, but there is hope on the horizon.

The efficacy of molecular targeted therapy and nivolumab therapy for metastatic non-clear cell renal cell carcinoma: A retrospective analysis using the Michinoku Japan urological cancer study group database

OBJECTIVES

To investigate the efficacy of pharmacotherapy for metastatic non-clear cell renal cell carcinoma (nccRCC) in Japanese population.

METHODS

In this retrospective analysis, we compared the time to treatment failure (TTF) for molecular-targeted agents as first-line therapy, or nivolumab therapy as sequential therapy between ccRCC and nccRCC using the data of Japanese metastatic RCC patients registered in the Michinoku Japan Urological Cancer Study Group database.

RESULTS

In total, 511 cases of ccRCC and 77 cases of nccRCC were treated with pharmacotherapy. After excluding the patients who received cytokine therapy, chemotherapy, or others, there were 391 ccRCC patients and 60 nccRCC patients who were treated with tyrosine kinase inhibitors (TKIs), and 7 ccRCC patients and 7 nccRCC patients who were treated with mammalian-target of rapamycin inhibitors (mTORIs). In addition, 132 ccRCC patients and 16 nccRCC patients received nivolumab. There was no significant difference in IMDC risk classification before first-line therapy between ccRCC and nccRCC groups, or in each subgroup within the nccRCC group. TTF for TKIs (161 days, 95% CI: 75-212 days) and mTORIs (21 days, 95% CI: 9-31 days) didn't differ significantly between nccRCC and ccRCC groups (205 days, 95% CI: 174-243 days and 33 days, 95% CI: 8-113 days, respectively). TTF for TKIs was significantly longer than that for mTORIs in nccRCC group (p<0.01). There was no significant difference in TTF between the different TKIs in nccRCC group. In addition, no significant difference in TTF for nivolumab was seen between ccRCC and nccRCC groups.

CONCLUSIONS

The results showed that the efficacy of molecular-targeted agents as first-line therapy was similar oncological outcomes between metastatic nccRCC and ccRCC in Japanese patients. TKIs may be more effective than mTORIs in metastatic nccRCC patients. Nivolumab administration might also be as effective in nccRCC patients as in ccRCC patients in Japanese population.

Comprehensive analyses of immune tumor microenvironment in papillary renal cell carcinoma

BACKGROUND

Papillary renal cell carcinoma (pRCC) is the most common non-clear cell RCC, and associated with poor outcomes in the metastatic setting. In this study, we aimed to comprehensively evaluate the immune tumor microenvironment (TME), largely unknown, of patients with metastatic pRCC and identify potential therapeutic targets.

METHODS

We performed quantitative gene expression analysis of TME using Microenvironment Cell Populations-counter (MCP-counter) methodology, on two independent cohorts of localized pRCC (n=271 and n=98). We then characterized the TME, using immunohistochemistry (n=38) and RNA-sequencing (RNA-seq) (n=30) on metastatic pRCC from the prospective AXIPAP trial cohort.

RESULTS

Unsupervised clustering identified two "TME subtypes", in each of the cohorts: the "immune-enriched" and the "immune-low". Within AXIPAP trial cohort, the "immune-enriched" cluster was significantly associated with a worse prognosis according to the median overall survival to 8 months (95% CI, 6 to 29) versus 37 months (95% CI, 20 to NA, p=0.001). The two immune signatures, Teff and JAVELIN Renal 101 Immuno signature, predictive of response to immune checkpoint inhibitors (CPI) in clear cell RCC, were significantly higher in the "immune-enriched" group (adjusted p<0.05). Finally, five differentially overexpressed genes were identified, corresponding mainly to B lymphocyte populations.

CONCLUSION

For the first time, using RNA-seq and immunohistochemistry, we have highlighted a specific immune TME subtype of metastatic pRCC, significantly more infiltrated with T and B immune population. This "immune-enriched" group appears to have a worse prognosis and could have a potential predictive value for response to immunotherapy, justifying the confirmation of these results in a cohort of metastatic pRCC treated with CPI and in combination with targeted therapies.

TRIAL REGISTRATION NUMBER

NCT02489695.

Real-world efficacy and safety of cabozantinib following immune checkpoint inhibitor failure in Japanese patients with advanced renal cell carcinoma

BACKGROUND

Real-world data of cabozantinib after failure of immune checkpoint inhibitors for advanced renal cell carcinoma in Japanese population are limited. Additionally, prognostic factors of cabozantinib in this setting are still unknown.

METHODS

We retrospectively evaluated data of 56 patients treated with cabozantinib subsequent to failed immune checkpoint inhibitors at four institutions. Regarding the efficacy profile, progression-free survival, overall survival and objective response rate were assessed. In terms of the safety profile, rate of adverse events, dose reduction and treatment interruption were assessed. Furthermore, risk factors of progression-free survival were analyzed.

RESULTS

Twenty-nine patients (52%) were treated with cabozantinib as second-line therapy. Most frequent prior immune checkpoint inhibitor treatment was nivolumab plus ipilimumab combination therapy as first-line therapy (n = 30, 54%). Median progression-free survival and overall survival were 9.76 and 25.5 months, respectively, and objective response rate was 34%. All patients experienced at least one adverse event, and grade ≥ 3 adverse events were observed in 31 patients (55%). Forty-four (79%) and 31 (55%) patients needed dose reduction and treatment interruption, respectively. Multivariate analysis showed that reduced initial dose (i.e. <60 mg) (hazard ratio: 2.50, P = 0.0355) and presence of lymph node metastasis (hazard ratio: 2.50, P = 0.0172) were independent factors of shorter progression-free survival.

CONCLUSION

Cabozantinib in Japanese patients with advanced renal cell carcinoma who failed immune checkpoint inhibitors was efficacious and had a manageable safety profile. These results appear to be similar to those of previous clinical trials.

Eosinophilic variant of chromophobe renal cell carcinoma metastasizing to the liver: Diagnostic pitfall

An 82-year-old man developed a hypervascular renal tumor, 2 cm in size, and multiple liver tumors. Liver tumors had obscured tumor margins on ultrasonography. Positron emission tomography/computed tomography (PET/CT) showed no areas of avid radiotracer uptake in the liver. Routine pathological examination failed to demonstrate tumor cells in 9 tissue samples obtained from repeated core needle biopsies. Even a frozen section of the liver segment 8 tumor further failed to prove malignant cells, and an additive frozen section of the liver section 2 tumor finally proved atypical cells growing in tubular and solid fashions with eosinophilic cytoplasm. Tumors showed expansive growth patterns, were in direct contact with normal liver cells, had abundant micro-vessels, had only sparse hyalinized septa, and had no pale cells. Immunostaining revealed the tumor cells to be positive for CD10, CD117, and E-cadherin and negative for CK7, and PAX8, leading to the diagnosis of metastatic chromophobe renal cell carcinoma (chRCC) in the liver. Arginase-1 immunostaining clearly demarcated the boundary between the chRCC cells and normal hepatic cells. Diagnostic physicians should note that chRCCs are of low-grade malignancy despite their abundant intra-tumoral blood flow and can often pose imaging and pathologic diagnostic difficulties.

Papillary Renal Cell Carcinoma: A Review of Prospective Clinical Trials

OPINION STATEMENT

PRCC is a unique histologic entity compared to other forms of renal cell carcinoma, harboring distinct molecular drivers. The WHO 2022 classification is further emphasizing the molecular biology by making molecular classifications of PRCC subclassifications and discontinuing the morphologic type 1 and type 2 classification system. We agree with this functional classification system and encourage all future clinical trials to only include patients with similar diagnosis instead of conducting basket trials (including all nccRCC together) which limits the scientific value of those conclusions. Based on recent disease-specific clinical trial (S1500, PAPMET), the current standard of care for patients with treatment naïve PRCC is cabozantinib. Prospective clinical trials clearly establish that immune checkpoint inhibitor therapy has meaningful activity in PRCC. The data to date include only single-arm clinical trials of combination immune therapy. Despite the positive and encouraging results, we need validation through randomized studies because of the overestimation of effect size seen in single-arm trials. These randomized trials are currently underway and enrolling. We strongly encourage all physicians to support these studies and enroll patients with PRCC to these trials in order to continue improving the standard of care.

Advanced Non-Clear Cell Renal Cell Carcinoma Treatments and Survival: A Real-World Single-Centre Experience

BACKGROUND

Non-clear cell renal cell carcinoma (nccRCC) is a heterogeneous group of cancer. Treatment recommendations are extrapolated from ccRCC and lack solid evidence. Here, we review advanced nccRCC patients treated at our institute.

PATIENTS AND METHODS

We collected retrospective data on all advanced nccRCC pts treated at the Istituto Oncologico Veneto from January 2008. We compared overall response rate (ORR), progression free survival (PFS) and overall survival (OS) according to histological subtypes and type of systemic treatments. Kaplan-Meier method, log-rank test and Cox regression were used to estimate and compare PFS and OS.

RESULTS

Of 1370 RCC patients, 289 had a diagnosis of nccRCC and 121 were eligible for the analysis. Fifty-three pts showed papillary histology (pRCC), 15 chromophobe; 37 unclassified RCC (NOS-RCC), 16 other histologies. Pts with chromophobe and other hystologies showed poorer survival rates compared to pRCC and NOS-RCC (mOS 10.7 vs. 20.7 vs. 30.7, p = 0.34). Pts treated with combination regimens achieved a better OS (30.7 vs. 13.7, p = 0.10), PFS (12.7 vs. 6.4, p = 0.10) and ORR (42.4% vs. 13.9%, p = 0.002) than those treated with monotherapy. IMDC and Meet-URO score retained their prognostic value.

CONCLUSION

Our retrospective real-life cohort of advanced nccRCC patients shows that immunotherapy-based combinations could improve ORR, PFS and OS compared to TKI monotherapy. Prospective trials for nccRCC patients utilizing novel therapies are ongoing and their results eagerly awaited.

Pembrolizumab plus lenvatinib as first-line therapy for advanced non-clear-cell renal cell carcinoma (KEYNOTE-B61): a single-arm, multicentre, phase 2 trial

BACKGROUND

Immunotherapy-based combinations including pembrolizumab plus lenvatinib are the standard of care for patients with first-line clear-cell renal cell carcinoma, but these combinations are not well characterised in non-clear-cell renal cell carcinoma. We aimed to assess the activity and safety of pembrolizumab plus lenvatinib as a first-line treatment for patients with advanced non-clear-cell renal cell carcinoma.

METHODS

KEYNOTE-B61 is a single-arm, phase 2 trial being conducted at 48 sites (hospitals and cancer centres) in 14 countries (Australia, Canada, France, Hungary, Ireland, Italy, Poland, South Korea, Russia, Spain, Türkiye, Ukraine, the UK, and the USA). Adult patients (aged ≥18 years) with previously untreated stage IV non-clear-cell renal cell carcinoma and a Karnofsky performance status of 70% or higher were eligible for enrolment. All enrolled patients received pembrolizumab 400 mg intravenously every 6 weeks for up to 18 cycles (2 years) plus lenvatinib 20 mg orally once daily or until disease progression, unacceptable toxicity, or withdrawal; lenvatinib could be continued beyond 2 years. The primary endpoint was the proportion of patients with a confirmed objective response as per adjusted Response Evaluation Criteria in Solid Tumours (version 1.1) assessed by independent central review. Activity and safety were analysed in all patients who received at least one dose of study treatment (the as-treated population). This trial is registered with ClinicalTrials.gov (NCT04704219) and is no longer recruiting participants but is ongoing.

FINDINGS

Between Feb 23, 2021, and Jan 21, 2022, 215 patients were screened; 158 were enrolled and received treatment. Median age at baseline was 60 years (IQR 52-69), 112 (71%) of 158 patients were male, 46 (29%) were female, 128 (81%) were White, 12 (8%) were Asian, three (2%) were Black or African American, and 15 (9%) were missing data on race. As of data cutoff (Nov 7, 2022), median study follow-up was 14·9 months (IQR 11·1-17·4). 78 of 158 patients had a confirmed objective response (49%; 95% CI 41-57), including nine (6%) patients with a confirmed complete response and 69 (44%) with a confirmed partial response. Grade 3-4 treatment-related adverse events occurred in 81 (51%) of 158 patients, the most common of which were hypertension (37 [23%] of 158), proteinuria (seven [4%]), and stomatitis (six [4%]). Serious treatment-related adverse events occurred in 31 (20%) of 158 patients. Eight (5%) patients died due to adverse events, none of which was considered related to the treatment by the investigators (one each of cardiac failure, peritonitis, pneumonia, sepsis, cerebrovascular accident, suicide, pneumothorax, and pulmonary embolism).

INTERPRETATION

Pembrolizumab plus lenvatinib has durable antitumour activity in patients with previously untreated advanced non-clear-cell renal cell carcinoma, with a safety profile consistent with that of previous studies. Results from KEYNOTE-B61 support the use of pembrolizumab plus lenvatinib as a first-line treatment option for these patients.

FUNDING

Merck Sharp & Dohme (a subsidiary of Merck & Co, NJ, USA), and Eisai.

Identification of prognostic and therapeutic biomarkers in type 2 papillary renal cell carcinoma

BACKGROUND

Papillary renal cell carcinoma (PRCC) can be divided into type 1 (PRCC1) and type 2 (PRCC2) and PRCC2 share a more invasive phenotype and worse prognosis. This study aims to identify potential prognostic and therapeutic biomarkers in PRCC2.

METHODS

A cohort from The Cancer Genome Atlas and two datasets from Gene Expression Omnibus were examined. Common differentially expressed genes (DEGs) were screened and potential biomarkers were explored by using Kaplan-Meier method and cox regression analysis. Functional enrichment analysis was utilized to evaluate the potential biological functions. Tumor infiltrating immune cells were estimated by CIBERSORT algorithm. Ninety-two PRCC2 samples from Fudan University Shanghai Cancer Center were obtained, and immunostaining was performed to validate prognostic and therapeutic significance of the potential biomarker.

RESULTS

PRCC2 has worse overall survival and shares distinct molecular characteristics from PRCC1. There was significant higher expression level of Targeting protein for Xklp2 (TPX2) in PRCC2 compared with normal tissues. Higher expression level of TPX2 was significantly associated with worse overall survival in PRCC2 and kinesin family genes expression were found significantly elevated in high risk PRCC2. Abundance of tumor infiltrating M1 macrophage was significantly higher in PRCC2 and it was also associated with worse overall survival. In the FUSCC cohort, higher TPX2 expression was significantly correlated with worse overall and progression-free survival. Retrospective analysis indicated that mTOR inhibitor (everolimus) had greater efficacy in the high-risk group than in the low-risk group (overall response rate: 28.6% vs. 16.7%) and that everolimus had greater efficacy than sunitinib in the high-risk group (overall response rate: 28.6% vs. 20%).

CONCLUSIONS

TPX2 was a prognostic and therapeutic biomarker in PRCC2. Higher abundance of tumor infiltrating M1 macrophage was significantly associated with worse overall survival in PRCC2. mTOR inhibitors may have good efficacy in patients with high-risk PRCC2.

An Update on the Treatment of Papillary Renal Cell Carcinoma

Papillary renal cell carcinoma (pRCC) is the second-most common subtype of kidney cancer following clear cell renal cell carcinoma (ccRCC), representing 15% of kidney cancers. Despite advances in therapy, including combination strategies with targeted therapies and immune checkpoint inhibitors, progress has lagged behind that of ccRCC. This is in part due to the heterogenous nature of the various subtypes of pRCC. More recently, investigators have turned efforts towards histology and biology-based trials. In this review, we outline some of the distinct biological characteristics of pRCC and discuss the most impactful clinical trials to date. Finally, we look ahead to several highly anticipated ongoing trials in pRCC.

To Investigate Growth Factor Receptor Targets and Generate Cancer Targeting Inhibitors

Receptor tyrosine kinase (RTK) regulates multiple pathways, including Mitogenactivated protein kinases (MAPKs), PI3/AKT, JAK/STAT pathway, etc. which has a significant role in the progression and metastasis of tumor. As RTK activation regulates numerous essential bodily processes, including cell proliferation and division, RTK dysregulation has been identified in many types of cancers. Targeting RTK is a significant challenge in cancer due to the abnormal upregulation and downregulation of RTK receptors subfamily EGFR, FGFR, PDGFR, VEGFR, and HGFR in the progression of cancer, which is governed by multiple RTK receptor signalling pathways and impacts treatment response and disease progression. In this review, an extensive focus has been carried out on the normal and abnormal signalling pathways of EGFR, FGFR, PDGFR, VEGFR, and HGFR and their association with cancer initiation and progression. These are explored as potential therapeutic cancer targets and therefore, the inhibitors were evaluated alone and merged with additional therapies in clinical trials aimed at combating global cancer.

How New Developments Impact Diagnosis in Existing Renal Neoplasms

In recent years, several emerging diagnostic entities have been described in renal cell carcinoma (RCC). However, our understanding of well-known and established entities has also grown. Clear cell papillary RCC is now relabeled as a tumor rather than carcinoma in view of its nonaggressive behavior. Renal tumors with a predominantly infiltrative pattern are very important for recognition, as most of these have aggressive behavior, including fumarate hydratase-deficient RCC, SMARCB1-deficient medullary carcinoma, collecting duct carcinoma, urothelial carcinoma, and metastases from other cancers.

Tumors masquerading as type 2 papillary renal cell carcinoma: pathologists' ever-expanding differential diagnosis for a heterogeneous group of entities

Although papillary renal cell carcinoma has historically been classified as either type 1 or type 2, data from The Cancer Genome Atlas (TCGA) has demonstrated significant genomic heterogeneity in tumors classified as "type 2 papillary renal cell carcinoma" (T2PRCC). Papillary renal cell carcinoma is expected to have a favorable clinical course compared to clear cell renal cell carcinoma (CCRCC). However, tumors with poor outcome more similar to CCRCC were included in the T2PRCC cohort studied by the TCGA. The differential diagnosis for T2PRCC includes a variety of other renal tumors, including aggressive entities such as TFE3 translocation-associated renal cell carcinoma, TFEB-amplified renal cell carcinoma, fumarate hydratase-deficient renal cell carcinoma, high-grade CCRCC, and collecting duct carcinoma. Accurate classification of these tumors is important for prognostication and selection of therapy.

Contemporary Drug Therapy for Renal Cell Carcinoma- Evidence Accumulation and Histological Implications in Treatment Strategy

Renal cell carcinoma (RCC) is a heterogeneous disease comprising a variety of histological subtypes. Approximately 70-80% of RCC cases are clear cell carcinoma (ccRCC), while the remaining subtypes constitute non-clear cell carcinoma (nccRCC). The medical treatment of RCC has greatly changed in recent years through advances in molecularly targeted therapies and immunotherapies. Most of the novel systemic therapies currently available have been approved based on ccRCC clinical trial data. nccRCC can be subdivided into more than 40 histological subtypes that have distinct clinical, histomorphological, immunohistochemical, and molecular features. These entities are listed as emerging in the 2022 World Health Organization classification. The diagnosis of nccRCC and treatments based on cancer histology and biology remain challenging due to the disease's rarity. We reviewed clinical trials focused on recent discoveries regarding clinicopathological features.

Sunitinib maleate administration before percutaneous CT-guided cryoablation for large renal cell carcinoma: A case report

A 60-year-old woman taking anti-platelet drugs was referred to the hospital for the treatment of advanced renal cell carcinoma. CT revealed that the tumor had a diameter of 5 cm and hyper-vascularity. Percutaneous CT-guided cryoablation (CA) was indicated. Since preprocedural arterial embolization failed to provide sufficient embolic effects, sunitinib maleate was administered. It provided good tumor devascularization and volume reduction, which corresponded to downstage. Therefore, the administration contributed to successfully performing subsequent percutaneous CT-guided CA with no serious hemorrhagic complications. Sunitinib maleate may be an alternative to conventional treatments before CA for renal cell carcinoma.

Advanced papillary renal cell carcinoma: Epidemiology, genomic drivers, current therapies, and ongoing trials

Papillary renal cell carcinoma (PRCC) is the most common subtype of non-clear cell renal cell carcinoma. PRCC can be subdivided into types 1 and 2 based on histology, each associated with different genetic mutations. The MET gene is commonly altered in type 1 PRCC while multiple alterations are involved in type 2 PRCC. PRCC is an aggressive cancer with a predominance in male and black patients and poor prognosis. Due to its rarity, there was a lack of convincing prospective data to guide treatment; hence, therapies were previously extrapolated from clear cell renal cell carcinoma with mixed results. More recently, some phase 2 trials focused on PRCC have been promising. Tyrosine kinase inhibitor (TKI) monotherapy is considered the standard of care, and combination strategies with TKIs and immune checkpoint inhibitors are emerging. Genetic profiling and large-scale clinical trials are needed to inform targeted treatment of PRCC.

Real world data of diagnosis, survival, and treatment outcomes in patients with metastatic non clear cell renal cell carcinoma

INTRODUCTION

Metastatic non clear cell renal cell carcinoma (nccRCC) is an heterogenous group, usually excluded from phase 3 trials. We report real life data of prognosis and systemic management of those patients.

METHODS

We retrospectively included 102 metastatic nccRCC patients (unspecified papillary, n = 10; type 1 and 2 papillary n = 10 and n = 32; translocation RCC, n = 9; chromophobe, n = 14; collecting duct, n = 14) treated between 2006 and 2020. Objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were evaluated.

RESULTS

Among patients who underwent pathological review, 40.8% presented a complete histological discordance. First line treatments were mainly tyrosine kinase inhibitor (60.8%), combination including immunotherapy (7.8%) or combination of chemotherapy (13.7%). Median ORR ranged from 0% in unspecified papillary RCC to 42.9% in type 1 papillary RCC. Median PFS ranged from 2.9 months in collecting duct carcinoma to 10.9 months in type 1 papillary RCC. Median OS ranged from 6.8 months in collecting duct carcinoma to 29.1 months in MiT family translocation RCC. Thirty (29.4%) patients were included in a treatment trial during their treatment course.

CONCLUSION

Metastatic nccRCC patients have variable prognosis due to heterogeneity of histological subtypes. Their diagnosis and access to therapeutic innovation remain suboptimal. Dedicated prospective trials are needed.

Papillary renal cell carcinoma: current and controversial issues

PURPOSE OF THE REVIEW

Papillary renal cell carcinoma (pRCC) is the second most frequent renal cancer subtype and represents 15-20% of all RCC. Classification of pRCC is changing because novel tumour entities have been discovered in the last years. In this review, we summarise recent studies relevant for the understanding of the molecular complexity and the broader differential diagnosis of pRCC.

RECENT FINDINGS

It has been 25 years ago, that pRCC was morphologically subdivided into type 1 and type 2. Recently described tumour entities in the 2022 WHO classification challenged this concept and allow a new view on the molecular background in pRCC. Biphasic hyalinizing psammomatous RCC and papillary renal neoplasm with reversed polarity are emerging tumour entities derived from the new concept of molecularly defined RCC subtypes. Immune checkpoint inhibition and tyrosine kinase inhibitors have been introduced as the new backbone in the first-line treatment of advanced pRCCs. To identify novel targeted treatments for patients with pRCC it is crucial to investigate the specific molecular background of pRCC considering emerging pRCC subtypes.

SUMMARY

In the future, a deeper understanding of the correlation between molecular aberrations and new pRCC subtypes may improve the classification of pRCC patients and could reveal potential predictive biomarkers for each subgroup.

Systematic Review of Treatment of Metastatic Non-Clear Cell Renal Cell Carcinoma

Background: Metastatic and unresectable non-clear cell renal cell carcinoma comprises more than a quarter of kidney cancers but does not have standardized treatment. Non-clear renal carcinoma consists of a variety of diverse histologic subtypes, including papillary, chromophobe, collecting duct, translocation, and medullary histologies, many of which carry a poor prognosis. Many prospective clinical trials exclude these kidney cancers, and for most clinical trials of non-clear cell renal cell carcinoma, only a small number of patients are enrolled. Objective: To perform a systematic review of recently published and currently enrolling prospective clinical trials for advanced non-clear cell renal cell carcinoma. Methods: A systematic search of Pubmed and MEDLINE (Ovid) was conducted as per PRISMA guidelines to identify recent prospective clinical trials in non-clear cell renal cell carcinoma. To ensure a thorough search, terms not only included non-clear cell renal carcinoma but also molecular subtypes. A review of currently enrolling clinical trials was conducted on Clinicaltrials.gov and the EU Clinical Trials Register as well. Results: A total of 33 prospective clinical trials with published results and 10 currently enrolling clinicals trials were identified. About half (48.5%) of these studies were reported in 2020 or 2021, and 36.4% were in the first-line setting. Treatments investigated in these trials included mTOR inhibitors, VEGF- and MET-targeted tyrosine kinase inhibitors, immune checkpoint inhibitors, and combinatorial strategies. Outcomes from these data revealed a wide range of response rate and progression free survival, favoring TKIs and immune checkpoint inhibitors -based combination regimens. Conclusions: Novel targeted therapies and immunotherapies have changed the landscape of treatment for advanced non-clear cell renal cell carcinoma. Combination regimens may provide even further clinical benefit and warrant further investigation in larger, randomized prospective clinical trials.

Stereotactic body radiotherapy-induced abscopal effect twice after pembrolizumab failure in hereditary leiomyomatosis and renal cell carcinoma: a case report with genetic and immunologic analysis

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a rare but aggressive disease. Immune checkpoint inhibitors (ICIs) have been an indispensable component for the management of advanced renal cell carcinoma, and stereotactic body radiotherapy (SBRT) has offered additional immunological effect boost for improving the treatment outcomes of the patients. However, the synergistic effect of ICIs with SBRT in HLRCC remains largely unexplored. We present the case of a 34-year-old woman with advanced HLRCC who underwent radical nephrectomy but soon relapsed at the retroperitoneal lymph nodes (RPLN). She was prescribed sunitinib but still progressed on twenty cycles with bulky RPLN and ascites. She was then treated with axitinib and pembrolizumab for twenty months, and received SBRT for the progression of RPLN upon which the first abscopal effect was observed via significant shrinkage of in-field and out-field tumor lesions. Five months later, she underwent a second course of SBRT for pelvic mass progression and the second abscopal effect was observed. Genetic and immunologic characteristics revealed a large number of tumor-infiltrating immune cells and high levels of PD-L1 expression. This case report demonstrates the synergistic effect of ICIs and SBRT in HLRCC and the potential mechanism for the repeated SBRT-induced abscopal effect, supporting the application of SBRT to oligometastatic lesion during ICIs treatment to delay disease progression. Further studies are needed to verify the strategy of combining ICIs and SBRT in advanced HLRCC.

Everolimus or sunitinib as first-line treatment of metastatic papillary renal cell carcinoma: A retrospective study of the GETUG group (Groupe d'Etude des Tumeurs Uro-Génitales)

BACKGROUND

Two phase II trials (NCT00688753 and NCT00541008) reported efficacy data of sunitinib and everolimus in first-line treatment of metastatic papillary renal cell carcinoma (mpRCC). Although most patients receive sunitinib or a mammalian target of rapamycin (mTOR) inhibitor in first- and second-line treatment, the optimal strategy remained unknown.

MATERIAL AND METHODS

In 23 centres of the Groupe d'Etude des Tumeurs Urogénitales group, after centralised pathological review, we analysed retrospectively progression-free survival (PFS) of patients with mpRCC treated in first-line treatment (PFS-1) with sunitinib or everolimus (primary end-point), PFS in second-line treatment (PFS-2), overall survival (OS), objective response rate, disease control rate (DCR), overall sequence and prognostic factors for OS (secondary end-points).

RESULTS

One hundred thirty-eight patients (119 men and 19 women), median age 62.5 years, with mpRCC type 1 (n = 24) or non-type 1 (n = 114), received first-line sunitinib (n = 107) or everolimus (n = 31). With a median follow-up of 92 months, we found no significant difference between the treatment groups in terms of PFS-1 (5.5 versus 6.2 months) and DCR (69% versus 83%). Ninety-eight patients received a second-line treatment, 69% with mTOR inhibitors after sunitinib and 100% with tyrosine kinase inhibitors after everolimus, with similar DCR (64% versus 58%), median PFS-2 (3.4 versus 4.8 months) and OS (16.0 versus 20.3 months). No factor was prognostic for PFS-1, whereas leukocytosis, anaemia and the time from diagnosis to first systemic therapy < 1 year were prognostic for OS. We found no prognostic difference between both pRCC subtypes. The International Metastatic Renal Cell Database Consortium risk factors were prognostic for OS.

CONCLUSION

Sunitinib and everolimus had similar efficacy in first-line treatment of patients with mpRCC.

Prognostic and Therapeutic Potential of the OIP5 Network in Papillary Renal Cell Carcinoma

Papillary renal cell carcinoma (pRCC) is an aggressive but minor type of RCC. The current understanding and management of pRCC remain poor. We report here OIP5 being a novel oncogenic factor and possessing robust prognostic values and therapeutic potential. OIP5 upregulation is observed in pRCC. The upregulation is associated with pRCC adverse features (T1P < T2P < CIMP, Stage1 + 2 < Stage 3 < Stage 4, and N0 < N1) and effectively stratifies the fatality risk. OIP5 promotes ACHN pRCC cell proliferation and xenograft formation; the latter is correlated with network alterations related to immune regulation, metabolism, and hypoxia. A set of differentially expressed genes (DEFs) was derived from ACHN OIP5 xenografts and primary pRCCs (n = 282) contingent to OIP5 upregulation; both DEG sets share 66 overlap genes. Overlap66 effectively predicts overall survival (p < 2 × 10^-16) and relapse (p < 2 × 10^-16) possibilities. High-risk tumors stratified by Overlap66 risk score possess an immune suppressive environment, evident by elevations in Treg cells and PD1 in CD8 T cells. Upregulation of PLK1 occurs in both xenografts and primary pRCC tumors with OIP5 elevations. PLK1 displays a synthetic lethality relationship with OIP5. PLK1 inhibitor BI2356 inhibits the growth of xenografts formed by ACHN OIP5 cells. Collectively, the OIP5 network can be explored for personalized therapies in management of pRCC patients.

Characteristics and Treatment Challenges of Non-Clear Cell Renal Cell Carcinoma

Non-clear cell renal cell carcinomas (RCC) comprise several rare and poorly described diseases, often characterized by bad prognosis and with no standard treatments available. The gap in their clinical management is linked to the poor molecular characterization in handling the treatment of non clear-cell RCC with untailored therapies. Due to their rarity, non-clear RCC are in fact under-represented in prospective randomized trials. Thus, treatment choices are based on extrapolating results from clear cell RCC trials, retrospective data, or case reports. Over the last two decades, various options have been considered as the mainstay for the treatment of metastatic RCC (mRCC), including angiogenesis inhibitors, vascular endothelial growth factor receptor inhibitors, other tyrosine kinase inhibitors (TKIs), as well as MET inhibitors and mammalian targeting of rapamycin (mTOR) inhibitors. More recently, the therapeutic armamentarium has been enriched with immunotherapy, alone or in combination with targeted agents that have been shown to significantly improve outcomes of mRCC patients, if compared to TKI single-agent. It has been widely proven that non-clear cell RCC is a morphologically and clinically distinct entity from its clear cell counterpart but more knowledge about its biology is certainly needed. Histology-specific collaborative trials are in fact now emerging to investigate different treatments for non-clear cell RCC. This review summarizes pathogenetic mechanisms of non-clear cell RCC, the evolution of treatment paradigms over the last few decades, with a focus on immunotherapy-based trials, and future potential treatment options.

The Molecular Characteristics of Non-Clear Cell Renal Cell Carcinoma: What's the Story Morning Glory?

Non-clear cell renal cell carcinomas are a miscellaneous group of tumors that include different histological subtypes, each one characterized by peculiarity in terms of genetic alteration, clinical behavior, prognosis, and treatment response. Because of their low incidence and poor enrollment in clinical trials, alongside their heterogeneity, additional efforts are required to better unveil the pathogenetic mechanisms and, consequently, to improve the treatment algorithm. Nowadays, tyrosine kinase inhibitors, mTOR and MET inhibitors, and even cisplatin-based chemotherapy and immunotherapy are potential weapons that are still under evaluation in this setting. Various biomarkers have been evaluated for detecting progression and monitoring renal cell carcinoma, but more studies are necessary to improve this field. In this review, we provide an overview on the molecular characteristics of this group of tumors and the recently published trials, giving an insight into what might become the future therapeutic standard in this complex world of non-clear cell kidney cancers.

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.

Response to systemic therapy in fumarate hydratase-deficient renal cell carcinoma

PURPOSE

Fumarate hydratase-deficient (FHdef) renal cell carcinoma (RCC) is a rare entity associated with the hereditary leiomyomatosis and RCC syndrome with no standard therapy approved. The aim of this retrospective study was to evaluate the efficacy of different systemic treatments in this population.

METHODS

We performed a multicentre retrospective analysis of Fhdef RCC patients to determine the response to systemic treatments. The endpoints were objective response rate (ORR), time-to-treatment failure (TTF), and overall survival (OS). The two latter were estimated using the Kaplan-Meier method.

RESULTS

Twenty-four Fhdef RCC patients were identified, and 21 under systemic therapy were included in the analysis: ten received cabozantinib, 14 received sunitinib, nine received "other antiangiogenics" (sorafenib, pazopanib, and axitinib), three received erlotinib-bevacizumab (E-B), three received mTOR inhibitors, and 11 received immune checkpoint blockers (ICBs). ORR for treatments were 50% for cabozantinib, 43% for sunitinib, 63% for "other antiangiogenics," and 30% for E-B, whereas ORR was 0% for mTOR inhibitors and 18% for ICBs. The median TTF (mTTF) was significantly higher with antiangiogenics (11.6 months) than with mTOR inhibitors (4.4 months) or ICBs (2.7 months). In the first-line setting, antiangiogenics presented a higher ORR compared with nivolumab-ipilimumab (64% versus 25%) and a significantly superior mTTF (11.0 months vs 2.5 months; p = 0.0027). The median OS from the start of the first systemic treatment was 44.0 months (95% confidence interval: 13.0-95.0).

CONCLUSIONS

We report the first European retrospective study of Fhdef RCC patients treated with systemic therapy with a remarkably long median OS of 44.0 months. Our results suggest that antiangiogenics may be superior to ICB/mTOR inhibitors in this population.

A challenging frontier - the genomics and therapeutics of nonclear cell renal cell carcinoma

PURPOSE OF REVIEW

As molecular profiling of renal cell carcinoma (RCC) continues to elucidate novel targets for nonclear cell histologies, understanding the landscape of these targets is of utmost importance. In this review, we highlight the genomic landscape of nonclear cell RCC and its implications for current and future systemic therapies.

RECENT FINDINGS

Several genomic studies have described the mutational burden among nonclear cell histologies. These studies have highlighted the importance of MET in papillary RCC and led to several clinical trials evaluating the efficacy of MET inhibitors for papillary RCC. The success of immune checkpoint inhibitors, such as ipilimumab and nivolumab, in clear cell RCC has led to ongoing trials evaluating these novel therapeutics in nonclear cell RCC.

SUMMARY

Genomic profiling has allowed for the evaluation of novel targets for nonclear cell RCC. This evolving therapeutic landscape is being explored in promising, ongoing trials that have the potential for changing how nonclear cell RCC is managed.

Modest efficacy of nivolumab plus ipilimumab in patients with papillary renal cell carcinoma

PURPOSE

Combined immunotherapy of nivolumab plus ipilimumab for intermediate- and poor-risk metastatic clear cell renal cell carcinoma showed prolonged progression-free survival and high objective response rate in a randomized phase III clinical trial. However, the efficacy of this treatment for papillary renal cell carcinoma remains unclear. In the present study, we analysed the efficacy of nivolumab plus ipilimumab therapy for papillary renal cell carcinoma compared with that for clear cell renal cell carcinoma.

MATERIALS AND METHODS

This is a retrospective study of 30 patients with metastatic renal cell carcinoma who received nivolumab and ipilimumab as first-line therapy between December 2015 and May 2020. The objective response rate, progression-free survival and toxicity were compared between the two groups (clear cell renal cell carcinoma and papillary renal cell carcinoma).

RESULTS

Out of 30 patients, 7 and 23 were diagnosed with papillary renal cell carcinoma and clear cell renal cell carcinoma, respectively. With a median follow-up of 7.2 months, the median progression-free survival was significantly shorter in papillary renal cell carcinoma than in clear cell renal cell carcinoma (2.4 vs. 28.1 months, P = 0.014). Of the seven patients with papillary renal cell carcinoma, one had partial response, one had stable disease and five had progressive disease, resulting in an objective response rate of 14.2%, which was lower compared to that of clear cell renal cell carcinoma (14.2 vs. 52.1%, P = 0.06). Discontinuation due to toxicity was not observed with papillary renal cell carcinoma, meanwhile 60.8% of patient with clear cell renal cell carcinoma discontinued treatment due to toxicity.

CONCLUSION

Nivolumab plus ipilimumab had modest efficacy for papillary renal cell carcinoma compared with that for clear cell renal cell carcinoma. Nivolumab plus ipilimumab remains an option for a limited number of patients with intermediate- or poor-risk papillary renal cell carcinoma.

Non-clear cell renal carcinomas: Review of new molecular insights and recent clinical data

Non-clear cell renal cell carcinomas (nccRCC) represent a highly heterogeneous group of kidney tumors, consisting of the following subtypes: papillary carcinomas, chromophobe renal cell carcinoma, so-called unclassified carcinomas or aggressive uncommon carcinomas such as Bellini carcinoma, renal cell carcinoma (RCC) with ALK rearrangement or fumarate hydratase-deficient RCC. Although non-clear cell cancers account for only 15 to 30% of renal tumors, they are often misclassified and accurate diagnosis continues to be an issue in clinical practice. Current therapeutic strategy of metastatic nccRCC is based primarily on guidelines established for clear cell tumors, the most common subtype, however this approach remains poorly defined. To date, published clinical trials for all histological nccRCC subtypes have been collectively characterized into one group, in contrast to clear cell RCC, and given the small numbers of cases, the interpretation of study results continues to be challenging. This review summarizes the available literature for each nccRCC subtype and highlights the lack of supportive evidence from prospective clinical trials and retrospective studies. Future trials should evaluate treatment approaches which focus on a specific histological subtype and progress in treating nccRCC will be contingent on understanding the unique biology of their individual histologies.

A comparison of sunitinib with cabozantinib, crizotinib, and savolitinib for treatment of advanced papillary renal cell carcinoma: a randomised, open-label, phase 2 trial

BACKGROUND

MET (also known as hepatocyte growth factor receptor) signalling is a key driver of papillary renal cell carcinoma (PRCC). Given that no optimal therapy for metastatic PRCC exists, we aimed to compare an existing standard of care, sunitinib, with the MET kinase inhibitors cabozantinib, crizotinib, and savolitinib for treatment of patients with PRCC.

METHODS

We did a randomised, open-label, phase 2 trial done in 65 centres in the USA and Canada. Eligible patients were aged 18 years or older with metastatic PRCC who had received up to one previous therapy (excluding vascular endothelial growth factor-directed and MET-directed agents). Patients were randomly assigned to receive sunitinib, cabozantinib, crizotinib, or savolitinib, with stratification by receipt of previous therapy and PRCC subtype. All drug doses were administered orally: sunitinib 50 mg, 4 weeks on and 2 weeks off (dose reductions to 37·5 mg and 25 mg allowed); cabozantinib 60 mg daily (reductions to 40 mg and 20 mg allowed); crizotinib 250 mg twice daily (reductions to 200 mg twice daily and 250 mg once daily allowed); and savolitinib 600 mg daily (reductions to 400 mg and 200 mg allowed). Progression-free survival (PFS) was the primary endpoint. Analyses were done in an intention-to-treat population, with patients who did not receive protocol therapy excluded from safety analyses. This trial is registered with ClinicalTrials.gov, NCT02761057.

FINDINGS

Between April 5, 2016, and Dec 15, 2019, 152 patients were randomly assigned to one of four study groups. Five patients were identified as ineligible post-randomisation and were excluded from these analyses, resulting in 147 eligible patients. Assignment to the savolitinib (29 patients) and crizotinib (28 patients) groups was halted after a prespecified futility analysis; planned accrual was completed for both sunitinib (46 patients) and cabozantinib (44 patients) groups. PFS was longer in patients in the cabozantinib group (median 9·0 months, 95% CI 6-12) than in the sunitinib group (5·6 months, 3-7; hazard ratio for progression or death 0·60, 0·37-0·97, one-sided p=0·019). Response rate for cabozantinib was 23% versus 4% for sunitinib (two-sided p=0·010). Savolitinib and crizotinib did not improve PFS compared with sunitinib. Grade 3 or 4 adverse events occurred in 31 (69%) of 45 patients receiving sunitinib, 32 (74%) of 43 receiving cabozantinib, ten (37%) of 27 receiving crizotinib, and 11 (39%) of 28 receiving savolitinib; one grade 5 thromboembolic event was recorded in the cabozantinib group.

INTERPRETATION

Cabozantinib treatment resulted in significantly longer PFS compared with sunitinib in patients with metastatic PRCC.

FUNDING

National Institutes of Health and National Cancer Institute.

Long-term disease control of metastatic type 2 papillary renal cell carcinoma using local treatment and molecular targeted therapy: A case report

A 46-year-old man underwent right partial nephrectomy for type 2 papillary renal cell carcinoma (PRCC) in 2011. Lung metastasis and lymph node (LN) metastases around the inferior vena cave appeared in 2012. A right radical nephrectomy and extensive LN dissection was performed and the resection of lung metastasis was performed one month after the nephrectomy. Mediastinal LN metastases occurred in 2013, and resection of the affected LNs was performed. Sunitinib and zoledronic acid was started in 2014 because mediastinal LN swelling and multiple bone metastases appeared. Sunitinib treatment was stopped soon after due to adverse events and axitinib treatment was started. Axitinib was effective and the patient had stable disease for 30 months. Adverse events were successfully controlled by dose reduction and periodic drug withdrawal schedules (for example, 5 days on, 2 days off). Axitinib was further continued for 19 months as the metastatic lesions had progressed slowly. Temsirolimus treatment was started in 2019, but it was stopped after three cycles due to interstitial pneumonia. The patient died 80 months after the initial recurrence. Using multidisciplinary treatment, durable disease control was achieved in a patient with metastatic type 2 PRCC.

Are tyrosine kinase inhibitors fit for purpose in the treatment of metastatic papillary renal cell carcinoma?

Renal cell carcinoma encompasses a range of histological subtypes. The treatment of metastatic disease in this context remains challenging. Papillary renal cell carcinoma is the second most common subtype and forms a significant subsection of non-clear cell renal cell carcinoma. Tyrosine kinase inhibitors form a significant part of the treatment of this largely incurable disease; however, outcomes tend to be poor. The aim of this article is to scrutinise whether these treatments are evidence-based in their use for metastatic papillary renal cell carcinoma and if good outcomes are reported. A literature review was made using PubMed of major prospective and retrospective studies. The European Association of Urology and European Society of Medical Oncology have both published guidance suggesting sunitinib should be offered first line in the treatment of metastatic papillary renal cell carcinoma. This, however, is based upon weak evidence produced by the ASPEN trial, although this did not discriminate between non-clear cell subtypes and results in further studies were modest. The National Institute for Care and Health Excellence has recently published new guidelines for the use of cabozantinib, which has shown evidence of improved progression-free survival and overall response rates compared with sunitinib. Unfortunately, many of the relevant studies did not specifically assess these treatments in patients solely with papillary renal cell carcinoma and had modest overall success. There is weak evidence that tyrosine kinase inhibitors give significant benefit in those patients with metastatic papillary renal cell carcinoma.

Level of evidence: 2a

Treatment outcomes of metastatic nonclear cell renal cell carcinoma: A single institution retrospective analysis

Introduction:

Nonclear cell (NCC) metastatic renal cell carcinoma (mRCC) is a biologically heterogeneous entity. We report the outcomes of NCC mRCC treated with first-line vascular endothelial growth factor (VEGF) inhibitors or mammalian target of rapamycin (mTOR) inhibitors at our institute. This is first such report from India.

Methods:

This is a retrospective analysis of the 40 consecutive patients of NCC mRCC treated between January 2013 and June 2015 in routine clinical practice at our institute. The primary endpoint analyzed was overall survival (OS) with respect to the type of first-line treatment and tumor histology.

Results:

The most common histological subtype was papillary in 25 patients (62.5%) followed by sarcomatoid in six (15%), chromophobe in 5 (12.5%), translocation-associated in one patient, and other nonspecified in three patients. First-line treatment was sorafenib in 14 (35%), sunitinib in 9 (22.5%), pazopanib in 8 (20%), everolimus in seven (17.5%), and best-supportive care (BSC) in two (5%) patients. Partial response, stable disease, and progression was observed in six (15%), 13 (32.5%), and nine (22.5%) cases, respectively, as the best response to first-line treatment. The median OS was 11.7 months and median event-free survival was 6.1 months in the whole cohort. The median OS in months for different first-line treatments were as follows: sorafenib (16.2), sunitinib (11.7), pazopanib (not reached, mean-23.9 ± 6.0), everolimus (4.1) and BSC (0.6) and for different histological subtypes were as follows: papillary (9.8), chromophobe (not reached, mean-30.3 ± 8.4), sarcomatoid (4.1), and others (7.9).

Conclusions:

Chromophobe histology has a better outcome compared to other histological subtypes, and anti-VEGF tyrosine kinase inhibitors are preferable first-line agents compared to mTOR inhibitors.

Hereditary Leiomyomatosis and Renal Cell Cancer Syndrome in Spain: Clinical and Genetic Characterization

Hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) is a very rare hereditary disorder characterized by cutaneous leiomyomas (CLMs), uterine leiomyomas (ULMs), renal cysts (RCys) and renal cell cancers (RCCs). We aimed to describe the genetics, clinical features and potential genotype-phenotype associations in the largest cohort of fumarate hydratase enzyme mutation carriers known from Spain using a multicentre, retrospective study of individuals with a genetic or clinical diagnosis of HLRCC. We collected clinical information from medical records, analysed genetic variants and looked for genotype-phenotype associations. Analyses were performed using R 3.6.0. software. We included 197 individuals: 74 index cases and 123 relatives. CLMs were diagnosed in 65% of patients, ULMs in 90% of women, RCys in 37% and RCC in 10.9%. Twenty-seven different pathogenic variants were detected, 12 (44%) of them not reported previously. Patients with missense pathogenic variants showed higher frequencies of CLMs, ULMs and RCys, than those with loss-of-function variants (p = 0.0380, p = 0.0015 and p = 0.024, respectively). This is the first report of patients with HLRCC from Spain. The frequency of RCCs was lower than those reported in the previously published series. Individuals with missense pathogenic variants had higher frequencies of CLMs, ULMs and RCys.

Treatment strategy for papillary renal cell carcinoma type 2: a case series of seven patients treated based on next generation sequencing data

Background

Papillary renal cell carcinoma type 2 (PRCC2) is refractory to systemic treatment and has a dismal prognosis. Previous studies showed that genetic alterations in PRCC2 were heterogeneous regardless of germline or somatic mutations. In this study, we aimed to perform precision treatment of PRCC2 based on genetic information.

Methods

We performed exome and genome sequencing of tumor tissues and matched normal samples. Based on sequencing data, we treated patients with metastatic PRCC2 using precision oncology.

Results

Four patients underwent curative surgery of PRCC2 and three patients had metastatic PRCC2. All PRCC2 heterogeneously harbored own driver mutations. Two out of the three patients with metastatic disease had fumarate hydratase (FH) germline mutations. One patient with a germline FH mutation was diagnosed with hereditary leiomyomatosis RCC. He was treated with bevacizumab and erlotinib combination and showed a durable response. The other metastatic PRCC2 patient harboring a germline FH mutation had an additional somatic FH mutation and was durably controlled with pazopanib. Other metastatic PRCC2 patient with somatic PBRM1 and SETD2 mutations had over 5 years of overall survival with axitinib treatment.

Conclusions

We performed precision systemic treatment based on genetic information. Genome sequencing could help identify candidates for targeted therapy in PRCC2, a genetically heterogeneous disease.

A deep learning and similarity-based hierarchical clustering approach for pathological stage prediction of papillary renal cell carcinoma

Papillary renal cell carcinoma (pRCC), which accounts for 10–15% of renal cell carcinomas, is the second most frequent renal cell carcinoma. pRCC patient classification is difficult because of disease heterogeneity, histologic subtypes, and variations in both disease progression and patient outcomes. Nevertheless, symptom-based patient classification is indispensable in deciding treatment options. Here we introduce a prediction method for distinguishing pRCC pathological tumour stages using deep learning and similarity-based hierarchical clustering approaches. Differentially expressed genes (DEGs) were identified from gene expression data of pRCC patients retrieved from TCGA. Thirty-three of these genes were distinguished based on expression in early or late stage pRCC using the Wilcoxon rank sum test, confidence interval, and LASSO regression. Then, a deep learning model was constructed to predict tumour progression with an accuracy of 0.942 and area under curve of 0.933. Furthermore, pathological sub-stage information with an accuracy of 0.857 was obtained via similarity-based hierarchical clustering using 18 DEGs between stages I and II, and 11 DEGs between stages III and IV, identified through Wilcoxon rank sum test and quantile approach. Additionally, we offer this classification process as an R function. This is the first report of a model distinguishing the pathological tumour stages of pRCC using deep learning and similarity-based hierarchical clustering methods. Our findings are potentially applicable for improving early detection and treatment of pRCC and establishing a clearer classification of the pathological stages in other tumours.

Unusual etiology of persistent fever after urinary tract infection: Papillary renal cell carcinoma

This manuscript presents a case report of type 2 papillary renal cell carcinoma presenting with persistent fever and abdominal tenderness after treatment for urinary tract infection. The purpose of this article is to aid physicians in understanding that papillary renal cell carcinomas should be considered in patients with a persistent fever after urinary tract infection and computed tomography was useful to diagnose this entity.

Efficacy of Savolitinib vs Sunitinib in Patients With MET-Driven Papillary Renal Cell Carcinoma: The SAVOIR Phase 3 Randomized Clinical Trial

Importance

Papillary renal cell carcinoma (PRCC) is the most common type of non-clear cell RCC. Because some cases of PRCC are MET-driven, MET inhibition could be a targeted treatment approach. In previous studies, savolitinib (AZD6094, HMPL-504, volitinib), a highly selective MET-tyrosine kinase inhibitor, demonstrated antitumor activity in this patient group.

Objective

To determine whether savolitinib is a better treatment option for this patient population, vs standard of care, sunitinib.

Design, Setting, and Participants

The SAVOIR phase 3, open-label, randomized clinical trial was a multicenter study carried out in 32 centers in 7 countries between July 2017 and the data cutoff in August 2019. Overall, 360 to 450 patients were to be screened to randomize approximately 180 patients. Patients were adults with MET-driven (centrally confirmed), metastatic PRCC, with 1 or more measurable lesions. Exclusion criteria included prior receipt of sunitinib or MET inhibitor treatment. Overall, 254 patients were screened.

Interventions

Patients received 600 mg of savolitinib orally once daily (qd), or 50 mg of sunitinib orally qd for 4 weeks, followed by 2 weeks without treatment.

Main Outcomes and Measures

The primary end point was progression-free survival (PFS, assessed by investigator and confirmed by blinded independent central review). Secondary end points included overall survival (OS), objective response rate (ORR), duration of response, and safety/tolerability.

Results

At data cutoff, 60 patients were randomized (savolitinib n = 33; sunitinib n = 27); most patients had chromosome 7 gain (savolitinib, 30 [91%]; sunitinib, 26 [96%]) and no prior therapy (savolitinib, 28 [85%]; sunitinib, 25 [93%]). For savolitinib and sunitinib, 4 (12%) and 10 (37%) patients were women, and the median (range) age was 60 (23-78) and 65 (31-77) years, respectively. Following availability of external data on PFS with sunitinib in patients with MET-driven disease, study enrollment was closed. Progression-free survival, OS, and ORR were numerically greater with savolitinib vs sunitinib. Median PFS was not statistically different between the 2 groups: 7.0 months (95% CI, 2.8-not calculated) for savolitinib and 5.6 months (95% CI, 4.1-6.9) for sunitinib (hazard ratio [HR], 0.71; 95% CI, 0.37-1.36; P = .31). For savolitinib and sunitinib respectively, grade 3 or higher adverse events (AEs) were reported in 14 (42%) and 22 (81%) of patients and AE-related dose modifications in 10 (30%) and 20 (74%). After discontinuation, 12 (36%) and 5 (19%) of patients on savolitinib and sunitinib respectively, received subsequent anticancer therapy.

Conclusions and Relevance

Although patient numbers and follow-up were limited, savolitinib demonstrated encouraging efficacy vs sunitinib, with fewer grade 3 or higher AEs and dose modifications. Further investigation of savolitinib as a treatment option for MET-driven PRCC is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT03091192.

Identification of a three-miRNA signature as a novel prognostic model for papillary renal cell carcinoma

Background

Papillary renal cell carcinoma (pRCC) accounting for near 20% of renal cell carcinoma is the second most common histological subtype. MiRNAs have been demonstrated to played significant roles on predicting prognosis of patients with tumors. An appropriate and comprehensive miRNAs analysis based on a great deal of pRCC samples from The Cancer Genome Atlas (TCGA) will provide perspective in this field.

Methods

We integrated the expression of mRNAs, miRNAs and the relevant clinical data of 321 pRCC patients recorded in the TCGA database. The survival-related differential expressed miRNAs (sDEmiRs) were estimated by COX regression analysis. The high-risk group and the low-risk group were separated by the median risk score of the risk score model (RSM) based on three screened sDEmiRs. The target genes, underlying molecular mechanisms of these sDEmiRs were explored by computational biology. The expression levels of the three sDEmiRs and their correlations with clinicopathological parameters were further validated by qPCR.

Results

Based on univariate COX analysis (P < 0.001), eighteen differential expressed miRNAs (DEmiRs) were remarkably related with the overall survival (OS) of pRCC patients. Three sDEmiRs with the most significant prognostic values (miR-34a-5p, miR-410-3p and miR-6720-3p) were employed to establish the RSM which was certified as an independent prognosis factor and closely correlated with OS. In the verification of clinical samples, the overexpression of miR-410-3p and miR-6720-3p were detected to be associated with the advanced T-stages, while miR-34a-5p showed the reversed results.

Conclusion

The study developed a RSM based on the identified sDEmiRs with significant prognosis prediction values for pRCC patients. The results pave the avenue for establishing and optimizing a reliable and referable risk assessing model and provide novel insight into the researches of biomarkers and clinical treatment strategies.

Are immune checkpoint inhibitors a valid option for papillary renal cell carcinoma? A multicentre retrospective study

BACKGROUND

Papillary renal cell carcinoma (pRCC) is the most common non-clear cell RCC (nccRCC). Pivotal studies evaluating immune checkpoint inhibitors mostly excluded nccRCC. The aim of this retrospective and multicentre study was to evaluate the activity of programmed death-1 (PD-1)/ programmed death-ligand 1 (PD-L1) inhibitors specifically in metastatic pRCC.

METHODS

The primary end-point was time to treatment failure (TTF). Secondary endpoints included objective response rate (ORR), overall survival (OS) and treatment-related adverse events (TRAEs).

RESULTS

From 02/2016 to 01/2019, 57 patients with pRCC were included. Histology included 16 (28%) type 1 pRCC, 34 (60%) type 2 pRCC and 7 (12%) unclassified pRCC. Treatment with immune checkpoint inhibitors was used in the first-line setting in 4 patients (7%), in the second-line setting in 32 patients (56%) and in the third-line setting or more in 21 patients (37%). With a median follow-up of 12 months (95% confidence interval [CI]: 9.9-21.0), the median TTF was 3.1 months (95% CI: 2.7-5.0). Among the 55 patients evaluable for ORR, best response was complete response/partial response in 6 patients (11%), stable disease in 18 patients (33%) and progressive disease in 31 patients (56%). The median OS was 14.6 months (95% CI: 9.0- not reached). TRAEs of grade III-IV were noted in 6 patients (10%) leading to treatment discontinuation, and no grade V TRAEs were observed.

CONCLUSION

PD-1/PD-L1 inhibitors exhibit limited activity as monotherapy in this pRCC population, which remains an unmet need. Our findings underline the need for further prospective clinical trials evaluating immune checkpoint inhibitor combinations in patients with pRCC.

Management of Metastatic Nonclear Renal Cell Carcinoma: What Are the Options and Challenges?

This case presents a 68-yr-old female patient with primary metastatic nonclear renal cell carcinoma (RCC) with multiple bone lesions. The patient underwent a single resection of skull bone lesion (diagnostic for poorly differentiated carcinoma of unknown origin) and cytoreductive nephrectomy. The pathology of the kidney specimen demonstrated an oncocytic papillary RCC. Within 3 mo, she developed skeletal progressive disease and was started on systemic therapy (sunitinib). After initial stabilization, bone metastasis progressed during the third cycle of sunitinib and required second-line therapy (cabozantinib). One of the major unmet needs in non-clear cell RCC is the lack of specific systemic therapy. Data on immunotherapy are still limited. Inclusion of these patients in clinical trials is strongly recommended. PATIENT SUMMARY: Patients with metastatic kidney cancer who present with the less common histological subtype (non-clear cell) have poor survival. In this case, the patient responded to second-line therapy. Very few therapies provide response to treatment. Patients should be offered participation in clinical trials testing combinations with immunotherapy.

Management of Metastatic Renal Cell Carcinoma with Variant Histologies

Variant histology renal cell carcinoma (vRCC) encompasses rare non-clear cell subtypes that have long been associated with poor prognosis and minimal response to therapies targeting vascular endothelial growth factor and its receptor. Molecular advances have helped classify vRCC into distinct entities and identify putative targetable driver alterations, such as MET in papillary subtypes. More have since been identified in other vRCC subtypes, including alterations of tumor metabolism, chromatin remodeling genes, cell-cycle genes, and inactivation of tumor suppressors such as TP53 or NF2. New targeted therapies, as well as immune checkpoint inhibitors, have been in development and yielded encouraging results. Collaborative clinical trials will be an essential step toward better implementation of these regimens in clinical practice.