Prognostic significance of pT3a staging subclassifications in renal cell carcinoma: Not all pT3a are equal

OBJECTIVE

To examine the prognostic significance of perinephric fat, renal sinus fat, and renal vein invasion in patients with pT3a renal cell carcinoma (RCC) by histologic type.

METHODS

A population-based retrospective cohort study of patients with pT3aN0M0 RCC was performed using Surveillance, Epidemiology, and End Results (SEER) data for the years 2010 through 2019. Cox proportional hazards models were used to examine the relationship between pT3a subclassification groups and cancer-specific survival (CSS) by histological subtype (clear cell, papillary, chromophobe, and other).

RESULTS

The cohort consisted of 10,170 patients with pT3a RCC, including 8,446 (83.0%) with clear cell RCC and 1,724 (17.0%) with nonclear cell RCC (nccRCC). Median follow up was 36 months. Differences in CSS by pT3a subclassification groups were observed in all histological subtypes but were most pronounced in nccRCC, specifically papillary RCC. Compared to perinephric fat (PF) invasion only, renal vein (RV) invasion (HR = 4.9, 95%CI: 2.5-9.3, P < 0.01), renal sinus fat invasion (HR = 3.0, 95%CI: 1.4-6.2), RV and PF invasion (HR = 7.5, 95%CI: 3.5-16.0), and combination of all three characteristics (HR = 4.4, 95%CI: 1.2-15.5) were associated with worse CSS in patients with papillary RCC.

CONCLUSION

We examined the prognostic role of pT3a staging subclassifications in RCC by histologic subtype and observed survival differences, particularly in papillary RCC. Our findings highlight the need to refine pT3a staging criteria to help guide individualized, multimodal treatment strategies for locally advanced RCC.

Using the "2 standard deviations" rule with Dixon MRI to differentiate renal cell carcinoma types

BACKGROUND

Clear cell and non-clear cell renal cell carcinoma (RCC) are distinguishable based on microscopic fat, detectable by chemical shift MRI. However, these assessments are often subjective. Conversely, Dixon MRIs and the "2 standard deviations" rule (2SDR) are quantitative methods that may decrease diagnostic subjectivity. Therefore, this study assessed the value of the 2SDR for detecting microscopic fat and thus differentiating clear cell and non-clear cell RCC using Dixon MRI.

METHODS

This retrospective study included patients with RCC who underwent preoperative Dixon MRI. The patients were grouped based on tumor type: clear cell RCC and non-clear cell RCC. The 2SDR value was calculated based on in-phase and opposed-phase images and then compared between the two groups. 2SDR values >0 indicated clear cell RCCs, whereas values <0 indicated non-clear cell RCC.

RESULTS

We included 151 patients; 114 patients had clear cell RCC, of which 106 had a 2SDR value >0. Furthermore, 37 patients had non-clear cell RCC, of which 3 had a 2SDR value >0. The 2SDR value was significantly higher in the clear cell RCC group than in the non-clear cell RCC group (p = 0.000). Overall, 93.0% (106/114) and 8.1% (3/37) of patients with clear cell and non-clear cell RCC, respectively, had microscopic fat. The evaluation indices for this 2SDR method were: accuracy: 92.72%, sensitivity: 92.98%, specificity: 91.89%, positive predictive value: 97.25%, and negative predictive value: 80.95%.

CONCLUSIONS

2SDR values calculated from Dixon magnetic resonance images can differentiate clear cell from non-clear cell RCCs by detecting microscopic fat.

PRECIS

The "2 standard deviations" rule value calculated from Dixon MR images differentiates clear cell from non-clear cell renal cell carcinoma with high efficiency by detecting microscopic fat.

Clinical Features and Prognostic Factors of Metastatic Non-Clear Cell Renal Cell Carcinoma: A Multicenter Study from the Turkish Oncology Group Kidney Cancer Consortium

INTRODUCTION

We aimed to evaluate clinical features, prognostic factors, and treatment preferences in patients with non-clear cell renal cell carcinoma (nccRCC).

METHODS

Patients with metastatic nccRCC were selected from the Turkish Oncology Group Kidney Cancer Consortium (TKCC) database. Clinical features, prognostic factors, and overall survival (OS) outcomes were investigated.

RESULTS

A total of 118 patients diagnosed with nccRCC were included in this study. The median age at diagnosis was 62 years (interquartile range: 56-69). Papillary (57.6%) and chromophobe tumors (12.7%) are common histologic subtypes. Sarcomatoid differentiation was present in 19.5% of all patients. When the patients were categorized according to the International Metastatic RCC Database Consortium (IMDC) risk scores, 66.9% of the patients were found to be in the intermediate or poor risk group. Approximately half of the patients (55.9%) received interferon in the first line. At the median follow-up of 53.2 months (95% confidence interval [CI]: 34.7-71.8), the median OS was 19.3 months (95% CI: 14.1-24.5). In multivariate analysis, lung metastasis (hazard ratio [HR]:2.22, 95% CI: 1.23-3.99) and IMDC risk score (HR: 2.35, 95% CI: 1.01-5.44 for intermediate risk; HR: 8.86, 95% CI: 3.47-22.61 for poor risk) were found to be independent prognostic factors.

CONCLUSION

In this study, survival outcomes are consistent with previous studies. The IMDC risk score and lung metastasis are the independent prognostic factors for OS. This is an area that needs research to better treat this group of patients and create new treatment options.

Start of a New Era: Management of Non-Clear Cell Renal Cell Carcinoma in 2022

Purpose of Review

Historically, kidney cancer was diagnosed as either clear cell renal carcinoma (ccRCC) or non-clear cell renal carcinoma (nccRCC). With further research into the pathophysiology of nccRCC, multiple distinct subtypes have emerged creating distinct diagnosis, such as papillary renal cell carcinoma (PRCC), chromophobe renal cell carcinoma (crRCC), or unclassified carcinoma (cRCC). Many other kidney cancer subtypes are now included in the WHO classification system.

Recent Findings

The prognosis for each of the more frequently diagnosed types is discussed here along with treatment recommendations. The available clinical trial results and salient retrospective studies of each subtype are reviewed here to guide clinicians on the optimal treatment selection for patients with these rare histologic types or RCC.

Summary

Many nccRCC types are now recognized and each has unique molecular drivers which are different than ccRCC. The optimal treatment strategy is different for each subtype. The prognosis also differs based on the histology.

First-line pazopanib in patients with advanced non-clear cell renal carcinoma: An Italian case series

BACKGROUND

Non-clear cell (ncc) metastatic renal-cell carcinoma (RCC) has dismal results with standard systemic therapies and a generally worse prognosis when compared to its clear-cell counterpart. New systemic combination therapies have emerged for metastatic RCC (mRCC), but the pivotal phase III trials excluded patients with nccRCC, which constitute about 30% of metastatic RCC cases.

AIM

To provide a piece of real-life evidence on the use of pazopanib in this patient subgroup.

METHODS

The present study is a multicenter retrospective observational analysis aiming to assess the activity, efficacy, and safety of pazopanib as first-line therapy for advanced nccRCC patients treated in a real-life setting.

RESULTS

Overall, 48 patients were included. At the median follow-up of 40.6 mo, the objective response rate was 27.1%, the disease control rate was 83.3%, and the median progression-free survival and overall survival were 12.3 (95% confidence interval [CI]: 3.6-20.9) and 27.7 (95%CI: 18.2-37.1) mo, respectively. Grade 3 adverse events occurred in 20% of patients, and no grade 4 or 5 toxicities were found.

CONCLUSION

Pazopanib should be considered as a good first-line option for metastatic RCC with variant histology.

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.

Evolving treatment paradigm in metastatic non clear cell renal cell carcinoma

The treatment landscape for renal cell cancer (RCC) has evolved tremendously over the last two decades. Treatment algorithms have shifted from the highly toxic drugs with marginal benefit to better tolerated and more effective targeted therapy drugs. The latter include tyrosine kinase inhibitors, vascular endothelial growth factor inhibitors, MET inhibitors and, more recently, immunotherapy drugs alone and in various combinations. The majority of treatment algorithms for non-clear cell carcinoma have been based on extrapolating results from clear cell RCC trials and retrospective reviews. However, now that we understand that non-clear cell RCC is morphologically and clinically distinct from its clear cell counterpart, several collaborative clinical trials are underway for non-clear cell RCC. This review will delve into the historical aspects of treating non-clear cell RCC and the evolution of treatment paradigms over the last few decades with a focus on immunotherapy based trials.

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.

Bevacizumab Plus Erlotinib Combination Therapy for Advanced Hereditary Leiomyomatosis and Renal Cell Carcinoma-Associated Renal Cell Carcinoma: A Multicenter Retrospective Analysis in Korean Patients

PURPOSE

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a rare genetic syndrome resulting from germline mutations in fumarate hydratase. The combination of bevacizumab plus erlotinib showed promising interim results for HLRCC-associated RCC. Based on these results, we analyzed the outcome of bevacizumab plus erlotinib in Korean patients with HLRCC-associated RCC.

MATERIALS AND METHODS

We retrospectively reviewed the efficacy and safety of bevacizumab plus erlotinib in patients with HLRCC-associated RCC who were confirmed to have germline mutations in fumarate hydratase. The primary endpoint was the objective response rate (ORR), while the secondary endpoints were progression-free survival (PFS) and overall survival (OS).

RESULT

We identified 10 patients with advanced HLRCC-associated RCC who received bevacizumab plus erlotinib. Median age at diagnosis was 41 years, and five of the patients had received the combination as first- or second-line treatments. The ORR was 50% and the median PFS and OS were 13.3 and 14.1 months, respectively. Most adverse events were predictable and manageable by conventional measures, except for one instance where a patient died of gastrointestinal bleeding.

CONCLUSION

This is the first real-world outcome of the treatment of advanced HLRCC-associated RCC. Bevacizumab plus erlotinib therapy showed promising activity with moderate toxicity. We should be increasingly aware of HLRCC-associated RCC and bevacizumab plus erlotinib should be a first-line treatment for this condition, unless other promising data are published.

Cabozantinib for the treatment of patients with metastatic non-clear cell renal cell carcinoma: A retrospective analysis

BACKGROUND

Cabozantinib prolongs overall survival (OS) and progression-free survival (PFS) in patients with metastatic clear cell renal cell carcinoma (RCC) that progressed on first-line vascular endothelial growth factor receptor-tyrosine kinase inhibitor (VEGFR-TKI). The role of cabozantinib has not been established in non-clear cell renal cell carcinoma (nccRCC).

METHODS

This is a retrospective study of 30 patients with nccRCC who received cabozantinib from January 2013 to January 2017. Information collected included baseline characteristics, toxicity, dose reductions, PFS and OS. A fellowship trained abdominal radiologist, blinded to patient history and clinical data, assessed radiographic response using RECIST, v1.1.

RESULTS

With a median follow-up of 20.6 months (95% confidence interval [CI]: 11.4-28.8), median PFS was 8.6 months (95% CI: 6.1-14.7), and median OS was 25.4 months (95% CI: 15.5-35.4). Of the 28 patients with measurable disease, 4 had partial responses (2 papillary, 1 chromophobe and 1 unclassified RCC), 18 had stable disease (64.2%) and 6 had progressive disease (21.4%), resulting in a 14.3% objective response rate and a 78.6% disease control rate. Two patients with papillary RCC who had experienced disease progression on savolitinib achieved durable partial response and stable disease, respectively, following treatment with cabozantinib. Of the 21 patients who started cabozantinib at 60 mg/d, 12 (57.1%) required dose reduction due to toxicity.

CONCLUSION

In this retrospective study, cabozantinib produced a clinically meaningful benefit in patients with metastatic nccRCC, the majority of whom had disease progression on prior VEGFR-TKIs. Prospective trials of cabozantinib in nccRCC are warranted.

Application of the International Metastatic Renal Cell Carcinoma Database Consortium and Memorial Sloan Kettering Cancer Center Risk Models in Patients with Metastatic Non-Clear Cell Renal Cell Carcinoma: A Multi-Institutional Retrospective Study Using the Korean Metastatic Renal Cell Carcinoma Registry

Purpose

The International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) and the Memorial Sloan Kettering Cancer Center (MSKCC) risk models were developed predominantly with clear cell renal cell carcinoma (RCC). Accordingly, whether these two models could be applied to metastatic non-clear cell RCC (mNCCRCC) as well has not been well-known and was investigated herein.

Materials and Methods

From the Korean metastatic RCC registry, a total of 156 patients (8.1%) with mNCCRCC among the entire cohort of 1,922 patients were analyzed. Both models were applied to predict first-line progression-free survival (PFS), total PFS, and cancer-specific survival (CSS).

Results

The median first-line PFS, total PFS, and CSS were 5, 6, and 24 months, respectively. The IMDC risk model reliably discriminated three risk groups to predict survival: the median first-line PFS, total PFS, and CSS for the favorable, intermediate, and poor risk groups were 9, 5, and, 2 months (p=0.001); 14, 7, and 2 months (p < 0.001); and 41, 21, and 8 months (p < 0.001), all respectively. The MSKCC risk model also reliably differentiated three risk groups: 9, 5, and, 2 months (p=0.005); 10, 7, and 3 months (p=0.002); and 50, 21, and 8 months (p < 0.001), also all respectively. The concordance indices were 0.632 with the IMDC model and 0.643 with the MSKCC model for first-line PFS: 0.748 and 0.655 for CSS.

Conclusion

The current IMDC and MSKCC risk models reliably predict first-line PFS, total PFS, and CSS in mNCCRCC.

Evolving Treatment Paradigms in Non-clear Cell Kidney Cancer

OPINION STATEMENT

With no therapy specifically approved for non-clear cell cancers of the kidney, this disease remains an orphan site. Clear cell renal cancers (ccRCC) have seen a flurry of activity with multiple agents gaining Food and Drug Administration (FDA) approval in recent years. Simultaneously, non-clear cell RCC (ncRCC) have also seen a fair share of activity and exploration of new agents in development but no specific FDA approvals. Non-clear cell RCC is a mixed bag of multiple types of tumors originating in the kidney with distinct clinical molecular and genetic characteristics that vary significantly from clear cell carcinoma of the kidney. Conventionally, non-clear cell RCC have been treated with the same therapies as clear cell RCC. The clinical trials are typically conducted in ccRCC and the FDA approval covers non-clear cell cancer as well. Few randomized clinical trials have been conducted specifically for ncRCC. With the advent of molecular and tumor genomic testing, leading to discovery of targets and associated therapies for ncRCC, a specific review of the state of management of this disease is timely and clinically relevant.

Update on the treatment of metastatic clear cell and non-clear cell renal cell carcinoma

The advent of new knowledge surrounding the molecular pathology of renal-cell carcinoma (RCC) has culminated in a number of emerging targeted therapies. In just the last year, several new studies have been able to translate our understanding of tumor biology into significantly improved outcomes in patients with advanced RCC. The objective of this review is to describe new developments in targeted treatments and immunotherapies for patients with both clear-cell and non-clear cell metastatic RCC following the 2014 American Society of Clinical Oncology (ASCO) annual conference. We will discuss new applications of anti-VGF agents and PD-1 inhibitors in order to shed light on emerging avenues of RCC treatment that show considerable promise.