Outcomes of Patients with Renal Cell Carcinoma and Sarcomatoid Dedifferentiation Treated with Nephrectomy and Systemic Therapies: Comparison between the Cytokine and Targeted Therapy Eras

Epithelial-mesenchymal transition associated markers in sarcomatoid transformation of clear cell renal cell carcinoma

Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development and progression of many cancers. Partial EMT (pEMT) could represent a critical step in tumor migration and dissemination. Sarcomatoid renal cell carcinoma (sRCC) is an aggressive form of renal cell carcinoma (RCC) composed of a carcinomatous (sRCC-Ca) and sarcomatous (sRCC-Sa) component. The role of (p)EMT in the progression of RCC to sRCC remains unclear. The aim of this study was to investigate the involvement of (p)EMT in RCC and sRCC. Tissue samples from 10 patients with clear cell RCC (ccRCC) and 10 patients with sRCC were selected. The expression of main EMT markers (miR-200 family, miR-205, SNAI1/2, TWIST1/2, ZEB1/2, CDH1/2, VIM) was analyzed by qPCR in ccRCC, sRCC-Ca, and sRCC-Sa and compared to non-neoplastic tissue and between both groups. Expression of E-cadherin, N-cadherin, vimentin and ZEB2 was analyzed using immunohistochemistry. miR-200c was downregulated in sRCC-Ca compared to ccRCC, while miR-200a was downregulated in sRCC-Sa compared to ccRCC. CDH1 was downregulated in sRCC-Sa when compared to any other group. ZEB2 was downregulated in ccRCC and sRCC compared to corresponding non-neoplastic kidney. A positive correlation was observed between CDH1 expression and miR-200a/b/c. Our results suggest that full EMT is not present in sRCC. Instead, discreet molecular differences exist between ccRCC, sRCC-Ca, and sRCC-Sa, possibly representing distinct intermediary states undergoing pEMT.

Sarcomatoid and Rhabdoid Renal Cell Carcinoma: Clinical, Pathologic, and Molecular Genetic Features

Renal cell carcinoma (RCC) with sarcomatoid and rhabdoid morphologies has an aggressive biological behavior and a typically poor prognosis. The current 2022 WHO classification of renal tumors does not include them as distinct histologic entities but rather as transformational changes that may arise in a background of various distinct histologic types of RCC. The sarcomatoid component shows malignant spindle cells that may grow as intersecting fascicles, which is reminiscent of pleomorphic undifferentiated sarcoma. The rhabdoid cells are epithelioid cells with eccentrically located vesicular nuclei with prominent nucleoli and large intracytoplasmic eosinophilic inclusions. Studies have shown that RCCs with sarcomatoid and rhabdoid differentiation have distinctive molecular features. Sarcomatoid RCC harbors shared genomic alterations in carcinomatous and rhabdoid components, but also enrichment of specific genomic alterations in the sarcomatoid element, suggesting molecular pathways for development of sarcomatoid growth from a common clonal ancestor. Rhabdoid differentiation also arises through clonal evolution although less is known of specific genomic alterations in rhabdoid cells. Historically, treatment has lacked efficacy, although recently immunotherapy with PD-1/PD-L1/CTLA-4 inhibitors has produced significant clinical responses. Reporting of sarcomatoid and rhabdoid features in renal cell carcinoma is required by the College of American Pathologists and the International Collaboration on Cancer Reporting. This manuscript reviews the clinical, pathologic, and molecular features of sarcomatoid RCC and rhabdoid RCC with emphasis on the morphologic features of these tumors, significance of diagnostic recognition, the molecular mechanisms of tumorigenesis and differentiation along sarcomatoid and rhabdoid lines, and advances in treatment, particularly immunotherapy.

Renal cell carcinoma and venous tumor thrombus: predicting sarcomatoid dedifferentiation through preoperative IVIM-based MR imaging

PURPOSE

To evaluate the value of preoperative intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and conventional MRI indicators in identifying sarcomatoid dedifferentiation in renal cell carcinoma (RCC) and tumor thrombus.

METHODS

From September 2016 to April 2023, consecutive patients with RCC and tumor thrombus who received routine MRI examination and IVIM-DWI before radical resection were enrolled prospectively. Kaplan-Meier method with log-rank test was used to calculate and compare the survival probability. The preoperative imaging features were analyzed. Univariate and multivariable logistic regression analyses were employed to identify independent predictors of sarcomatoid dedifferentiation. The predictive ability was evaluated by receiver operating characteristic (ROC) curves.

RESULTS

Twenty-two patients (15.3%) of the 144 patients in the training set (median age, 58.0 years [IQR, 52.0-65.0 years]; 108 men) and 11 patients (22.4%) of the 49 patients in the test set (median age, 58.0 years [IQR, 53.0-63.0 years]; 38 men) had sarcomatoid dedifferentiated tumors. Patients with sarcomatoid-differentiated tumors had poor progress-free survival in the training set and test set (P < 0.001 and P = 0.007). f value (P = 0.011), mN stage (P = 0.007), and necrosis (P = 0.041) were independent predictors for predicting sarcomatoid dedifferentiation in the training set. The model combining conventional MRI features and f value had AUCs of 0.832 (95% CI 0.755-0.909) and 0.825 (95% CI 0.702-0.948) in predicting sarcomatoid dedifferentiation in the training set and test set.

CONCLUSION

It is feasible to preoperatively identify sarcomatoid dedifferentiation based on IVIM-DWI and conventional MR imaging indicators.

Demographic Patterns and Clinicopathological Analysis of Sarcomatoid Renal Cell Carcinoma in US Population

BACKGROUND

Sarcomatoid renal cell carcinoma (RCC) is defined by the presence of any amount of sarcomatoid components admixed with other RCC histologic subtypes. Our investigation utilizes a large, diverse set of sarcomatoid RCC patients to summarize clinical, demographic, and pathological factors along with demographic disparities that may affect the prognosis and survival of sarcomatoid RCC patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was employed to compile data from 2000 to 2018 from 2695 patients diagnosed with sarcomatoid RCC.

RESULTS

The mean age for sarcomatoid RCC diagnosis is 62.8 years. Males (68.2%) and White patients (82.6%) were more likely to be diagnosed with sarcomatoid RCC. Among the 64.4% of tumors with known size, 35.4% were less than 7 cm, 27.6% were 7.1 to 10 cm, and 36.4% were larger than 10 cm. Among the 95.8% of patients with known stage, 15.3% were localized, 28.9% were regionalized, and 55.8% were found in distant sites. Among the 44.2% of cases with known metastases site, lung was found to be the most common metastatic site.. Surgery was the most common treatment (70.9%). While the overall 5-year survival was 18.1%, it was 27.1% among patients who underwent surgery. Independent risk factors for mortality include age > 60 years, distant stage, and tumor size > 10 cm, per our multivariate analysis.

CONCLUSION

Sarcomatoid RCC most commonly affects White males in their seventh decade. Increased age, distant stage, and size > 10 cm tumor size have associations with unfavorable prognosis. Surgery is associated with better survival outcomes in localized disease and multimodal therapy (surgery with adjuvant chemoradiation was associated with better survival.).

Localised non-metastatic sarcomatoid renal cell carcinoma: a 31-year externally verified study

OBJECTIVE

To evaluate post-nephrectomy outcomes and predictors of cancer-specific survival (CSS) between patients with localised sarcomatoid renal cell carcinoma (sRCC) and those with Grade 4 RCC (non-sRCC), as most sRCC research focuses on advanced or metastatic disease with limited studies analysing outcomes of patients with localised non-metastatic sRCC.

PATIENTS AND METHODS

A total of 564 patients with localised RCC underwent partial or radical nephrectomy between June 1988 to March 2019 for sRCC (n = 204) or World Health Organization/International Society of Urological Pathology Grade 4 non-sRCC (n = 360). The CSS at every stage between groups was assessed. Phase III ASSURE clinical trial data were used to externally validate the CSS findings. The Mann-Whitney U-test and chi-squared test compared outcomes and the Kaplan-Meier method evaluated CSS, overall survival (OS) and recurrence-free survival. Clinicopathological features associated with RCC death were evaluated using Cox proportional hazards regression.

RESULTS

The median follow-up was 31.5 months. The median OS and CSS between the sRCC and Grade 4 non-sRCC groups was 45 vs 102 months and 49 vs 152 months, respectively (P < 0.001). At every stage, sRCC had worse CSS compared to Grade 4 non-sRCC. Notably, pT1 sRCC had worse CSS than pT3 Grade 4 non-sRCC. Negative predictors of CSS were sarcomatoid features, non-clear cell histology, positive margins, higher stage (pT3/pT4), and use of minimally invasive surgery (MIS). ASSURE external verification showed worse CSS in patients with sRCC (hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.12-2.36; P = 0.01), but not worse outcomes in MIS surgery (HR 1.39, 95% CI 0.75-2.56; P = 0.30).

CONCLUSIONS

Localised sRCC had worse CSS compared to Grade 4 non-sRCC at every stage. Negative survival predictors included positive margins, higher pathological stage, use of MIS, and non-clear cell histology. sRCC is an aggressive variant even at low stages requiring vigilant surveillance and possible inclusion in adjuvant therapy trials.

Immune checkpoint inhibitors in non-conventional histologies of renal-cell carcinoma

For years, prospective randomized clinical trials excluded patients with non-conventional histologies of renal cell carcinoma (RCC). The paucity of data has led to adopting the same treatment strategies used for clear-cell RCC (ccRCC). In the present narrative review, we explored state of the art about use of immune checkpoint inhibitors (ICIs) in variant histologies of RCC. According to the results collected, ICIs as monotherapy showed promising antitumor activity in advanced non-clear cell (ncc)RCC. The objective response rate (ORR) was similar to that observed with single-agent anti-PD-1 in the ccRCC population, either in the first-line or the second-line setting, and responder patients experienced an early and durable benefit. Combined ICI-based strategies have shown increasing evidence in nccRCC and robust results in the sarcomatoid variants of RCC. A definitive recommendation about treating non-conventional histologies, either in adjuvant or metastatic settings, should be supported by more extensive dedicated trials.

Cytoreductive Nephrectomy for Patients with Metastatic Sarcomatoid and/or Rhabdoid Renal Cell Carcinoma Treated with Immune Checkpoint Therapy

BACKGROUND

Renal cell carcinoma (RCC) with sarcomatoid and/or rhabdoid (S/R) dedifferentiation is a highly aggressive tumor with a poor prognosis. Immune checkpoint therapy (ICT) has shown significant treatment efficacy in this subtype. There remains uncertainly regarding the role of cytoreductive nephrectomy (CN) for patients with metastatic RCC (mRCC) with S/R who received ICT.

OBJECTIVE

Here, we report the outcomes with ICT for patients with mRCC and S/R dedifferentiation by CN status.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review was conducted of 157 patients with sarcomatoid, rhabdoid, or sarcomatoid plus rhabdoid dedifferentiation who received an ICT-based regimen at two cancer centers.

INTERVENTION

CN performed at any time point; nephrectomy with curative intent was excluded.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

ICT treatment duration (TD) and overall survival (OS) from ICT initiation were recorded. To address the immortal time bias, a time-dependent Cox regression model was generated that accounted for confounders identified by a directed acyclic graph as well as a time-dependent nephrectomy variable.

RESULTS AND LIMITATIONS

A total of 118 patients underwent CN, and of them, 89 underwent upfront CN. The results did not contradict the supposition that CN does not improve ICT TD (hazard ratio [HR] 0.98, 95% confidence interval [CI] 0.65-1.47, p = 0.94) or OS from ICT initiation (HR 0.79, 95% CI 0.47-1.33, p = 0.37). In patients who underwent upfront CN compared with those who did not undergo CN, there was no association with ICT duration or OS (HR 0.61, 95% CI 0.35-1.06, p = 0.08). A detailed clinical summary of 49 patients with mRCC and rhabdoid dedifferentiation is provided.

CONCLUSIONS

In this multi-institutional cohort of mRCC with S/R dedifferentiation treated with ICT, CN was not significantly associated with improved TD or superior OS when accounting for the lead time bias. There appears to be a subset of patients who derive meaningful benefit from CN, so improved tools for stratification prior to CN are needed to optimize outcomes.

PATIENT SUMMARY

Immunotherapy has improved outcomes for patients with metastatic renal cell carcinoma (mRCC) who have sarcomatoid and/or rhabdoid (S/R) dedifferentiation, which is an aggressive and uncommon feature; yet, the utility of a nephrectomy in this setting is unclear. We found that nephrectomy did not significantly improve survival or time on immunotherapy for these patients with mRCC and S/R dedifferentiation; yet, there may be a subset of patients who benefit from this surgical approach.

The Use of Radiomic Tools in Renal Mass Characterization

The incidence of renal mass detection has increased during recent decades, with an increased diagnosis of small renal masses, and a final benign diagnosis in some cases. To avoid unnecessary surgeries, there is an increasing interest in using radiomics tools to predict histological results, using radiological features. We performed a narrative review to evaluate the use of radiomics in renal mass characterization. Conventional images, such as computed tomography (CT) and magnetic resonance (MR), are the most common diagnostic tools in renal mass characterization. Distinguishing between benign and malignant tumors in small renal masses can be challenging using conventional methods. To improve subjective evaluation, the interest in using radiomics to obtain quantitative parameters from medical images has increased. Several studies have assessed this novel tool for renal mass characterization, comparing its ability to distinguish benign to malign tumors, the results in differentiating renal cell carcinoma subtypes, or the correlation with prognostic features, with other methods. In several studies, radiomic tools have shown a good accuracy in characterizing renal mass lesions. However, due to the heterogeneity in the radiomic model building, prospective and external validated studies are needed.

Interferon signaling promotes tolerance to chromosomal instability during metastatic evolution in renal cancer

Molecular routes to metastatic dissemination are critical determinants of aggressive cancers. Through in vivo CRISPR-Cas9 genome editing, we generated somatic mosaic genetically engineered models that faithfully recapitulate metastatic renal tumors. Disruption of 9p21 locus is an evolutionary driver to systemic disease through the rapid acquisition of complex karyotypes in cancer cells. Cross-species analysis revealed that recurrent patterns of copy number variations, including 21q loss and dysregulation of the interferon pathway, are major drivers of metastatic potential. In vitro and in vivo genomic engineering, leveraging loss-of-function studies, along with a model of partial trisomy of chromosome 21q, demonstrated a dosage-dependent effect of the interferon receptor genes cluster as an adaptive mechanism to deleterious chromosomal instability in metastatic progression. This work provides critical knowledge on drivers of renal cell carcinoma progression and defines the primary role of interferon signaling in constraining the propagation of aneuploid clones in cancer evolution.

Immune Checkpoint Inhibitors in Renal Cell Carcinoma: Molecular Basis and Rationale for Their Use in Clinical Practice

Renal cell carcinoma (RCC) is the seventh most common cancer in men and the ninth most common cancer in women worldwide. There is plenty of evidence about the role of the immune system in surveillance against tumors. Thanks to a better understanding of immunosurveillance mechanisms, immunotherapy has been introduced as a promising cancer treatment in recent years. Renal cell carcinoma (RCC) has long been thought chemoresistant but highly immunogenic. Considering that up to 30% of the patients present metastatic disease at diagnosis, and around 20–30% of patients undergoing surgery will suffer recurrence, we need to identify novel therapeutic targets. The introduction of immune checkpoint inhibitors (ICIs) in the clinical management of RCC has revolutionized the therapeutic approach against this tumor. Several clinical trials have shown that therapy with ICIs in combination or ICIs and the tyrosine kinase inhibitor has a very good response rate. In this review article we summarize the mechanisms of immunity modulation and immune checkpoints in RCC and discuss the potential therapeutic strategies in renal cancer treatment.

Significance of timing of therapeutic line on effectiveness of nivolumab for metastatic renal cell carcinoma

Objectives

This study aimed to clarify the significance of therapeutic timing on the effectiveness of nivolumab for treating metastatic renal cell carcinoma.

Marterials and methods

Fifty-eight patients with metastatic renal cell carcinoma treated with nivolumab monotherapy were retrospectively studied. Patients who were treated with nivolumab as second-line therapy were included in the second-line group, while the others were included in the later-line group. The clinicopathological characteristics, effects of nivolumab, and prognoses of these groups were compared.

Results

Twenty and thirty-eight patients were included in the second-line and later-line groups, respectively. There were no significant differences in the distribution of International Metastatic Renal Cell Carcinoma Database Consotium risk and other clinicopathological characteristics between the 2 groups. The proportion of patients whose objective best response was progressive disease in the second-line group was significantly lower than that in the later-line group (15% vs. 50%, p = 0.0090). The 50% progression-free survival with nivolumab in the second-line group was significantly better than that in the later-line group (not reached and 5 months, p = 0.0018). Multivariate analysis showed that the second-line setting was an independent predictive factor for better progression-free survival (p = 0.0028, hazard ratio = 0.108). The 50% overall survival after starting nivolumab in the second-line and later-line groups was not reached and 27.8 months, respectively (p = 0.2652).

Conclusions

The therapeutic efficacy of nivolumab as second-line therapy is expected to be better than that of later therapy.

The role of immunotherapy in non-clear cell renal cell carcinoma

The category of non-clear cell renal cell carcinoma (nccRCC) includes several clinically, histologically, and molecularly diverse entities. Traditionally, they comprise type 1 and type 2 papillary, chromophobe, unclassified, and other histologies (medullary, collecting duct carcinoma, and translocation-associated). Molecular knowledge has allowed the identification of some other specific subtypes, such as fumarate hydratase-deficient renal cell carcinoma (RCC) or succinate dehydrogenase-associated RCC. In addition, it has recognized some alterations with a possible predictive role, e.g., MET proto-oncogene receptor tyrosine kinase (MET) alterations in papillary tumors. Standard therapies for the management of advanced clear cell RCC (ccRCC), i.e., vascular endothelial growth factor receptor (VEGFR) pathway inhibitors and mammalian target of rapamycin inhibitors, have shown poorer results in nccRCC patients. Therefore, there is a need to improve the efficacy of the treatment for advanced nccRCC. Immunotherapy, especially immune checkpoint inhibitors (ICIs) targeting programmed death 1/programmed death ligand 1 and cytotoxic T-lymphocyte associated protein 4 (CTLA-4), has demonstrated a significant survival benefit in several malignant neoplasias, including ccRCC, with a proportion of patients achieving long survival. The combinations of ICI or ICI + VEGFR tyrosine kinase inhibitors (TKIs) are the standard of care in advanced ccRCC. Unfortunately, major pivotal trials did not include specific nccRCC populations. In recent years, several studies have retrospectively or prospectively evaluated ICIs alone or in combination with another ICI or with TKIs in nccRCC patients. In this article, we review data from available trials in order to elucidate clinical and molecular profiles that could benefit from immunotherapy approaches.

The Natural History of Renal-Cell Carcinoma with Sarcomatoid Differentiation, a Stage-by-Stage Analysis

BACKGROUND

Sarcomatoid differentiation in patients diagnosed with renal cell carcinoma (sRCC) imply aggressive behavior and often metastatic disease at the time of diagnosis. We aim to examine the overall survival (OS) in patients with sRCC using the National Cancer Database (NCDB).

MATERIALS AND METHODS

We identified patients diagnosed with sRCC between 2010-2015. We employed Kaplan-Meier curves and multivariable Cox proportional hazards regression models to examine the impact of several potential risk factors on OS in patients diagnosed with sRCC.

RESULTS

In total, 8582 patients with renal cancer were found to have sarcomatoid differentiation, with 4105 patients (47.8%) being diagnosed with AJCC stage IV disease. The median OS was 17.2 months (IQR 5.4, 68.7 months). Compared to patients who did not undergo surgery, OS was significantly longer in patients undergoing partial or total nephrectomy across all stages. This result remained consistent on multivariable Cox proportional hazards regression adjusting for patient and tumor characteristics (Surgery: Hazard ratio 0.54, 95%Confidence interval 0.43 - 0.68, P < .001).

CONCLUSION

In our cohort sRCC was found to have an unfavorable median OS, which was mainly caused by the high number of cases diagnosed with late-stage disease. Additionally, surgery was associated with favorable OS across all stages. This study supports the notion that surgical therapy, even in the setting of cytoreductive surgery, provides a survival benefit in patients with sRCC.

Long-term outcomes with nivolumab plus ipilimumab versus sunitinib in first-line treatment of patients with advanced sarcomatoid renal cell carcinoma

BACKGROUND

Patients with advanced renal cell carcinoma with sarcomatoid features (sRCC) have a poor prognosis and limited therapeutic options. First-line nivolumab plus ipilimumab (NIVO+IPI) provided efficacy benefits over sunitinib (SUN) in patients with intermediate/poor-risk sRCC at 42 months minimum follow-up in the phase 3 CheckMate 214 trial. In this exploratory post hoc analysis, we report clinical efficacy of NIVO+IPI in sRCC after a minimum follow-up of 5 years.

METHODS

In CheckMate 214, patients with clear cell advanced RCC were randomized to NIVO 3 mg/kg plus IPI 1 mg/kg every 3 weeks (four doses), then NIVO 3 mg/kg every 2 weeks versus SUN 50 mg once daily (4 weeks; 6-week cycles). Randomized patients with sRCC were identified via independent central pathology review of archival tumor tissue or histological classification per local pathology report. Overall survival (OS), as well as progression-free survival (PFS) and objective response rate (ORR) per independent radiology review using Response Evaluation Criteria in Solid Tumors V.1.1, were evaluated in all International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor-risk sRCC patients and by baseline tumor PD-L1 expression level (≥1% vs <1%). Safety outcomes are reported using descriptive statistics.

RESULTS

In total, 139 patients with intermediate/poor-risk sRCC were identified (NIVO+IPI, n=74; SUN, n=65). At 5 years minimum follow-up, more patients remained on treatment with NIVO+IPI versus SUN (12% vs zero). Efficacy benefits with NIVO+IPI versus SUN were maintained with median OS of 48.6 vs 14.2 months (HR 0.46), median PFS of 26.5 vs 5.5 months (HR 0.50), and ORR 60.8% vs 23.1%. In addition, median duration of response was longer (not reached vs 25.1 months), and more patients had complete responses (23.0% vs 6.2%) with NIVO+IPI versus SUN, respectively. Efficacy was better with NIVO+IPI versus SUN regardless of tumor PD-L1 expression, but the magnitude of OS, PFS, and ORR benefits with NIVO+IPI was greater for sRCC patients with tumor PD-L1 ≥1%. No new safety signals emerged in either arm with longer follow-up.

CONCLUSIONS

Among patients with intermediate/poor-risk sRCC, NIVO+IPI maintained long-term survival benefits and demonstrated durable and deep responses over SUN at minimum follow-up of 5 years, supporting NIVO+IPI as a preferred first-line therapy in this population.

TRIAL REGISTRATION NUMBER

NCT02231749.

The significance of sarcomatoid and rhabdoid dedifferentiation in renal cell carcinoma

Dedifferentiation in renal cell carcinoma (RCC), either sarcomatoid or rhabdoid, is an infrequent event that may occur heterogeneously in the setting of any RCC histology and is associated with poor outcomes. Sarcomatoid dedifferentiation is associated with inferior survival with angiogenesis targeted therapy and infrequent responses to cytotoxic chemotherapy. However, immune checkpoint therapy has significantly improved outcomes for patients with sarcomatoid dedifferentiation. Biologically, sarcomatoid dedifferentiation has increased programmed death-ligand 1 (PD-L1) expression and an inflamed tumor microenvironment, in addition to other distinct molecular alterations. Less is known about rhabdoid dedifferentiation from either a clinical, biological, or therapeutic perspective. In this focused review, we will discuss the prognostic implications, outcomes with systemic therapy, and underlying biology in RCC with either sarcomatoid or rhabdoid dedifferentiation present.

A Rare Case of Sarcomatoid Renal Cell Carcinoma in a Young Adult Patient

Background

Sarcomatoid differentiation is a rare condition that could present in different subtypes of renal cell carcinomas (RCCs) and is associated with a significantly poor prognosis. Sarcomatoid renal cell carcinoma (SRCC) patients are typically aged between 54 and 63, with a male-to-female ratio ranging from 1.3:1 to 2:1. Here, we report a case of SRCC in a 29-year-old female patient.

Case Presentation

A 29-year-old female presented with left flank pain. A large lump was palpated on left flank and there was costovertebral angle tenderness. The lump was enlarged, and the patient also suffered from anemia. Abdominopelvic CT demonstrated solid mass with an internal gliosis in the left part of the renal cortex and the solid component was enhanced with contrast admission. Then, the patient underwent left radical nephrectomy with wide perirenal excision and paraaortic lymph nodes resection. Histopathological examination revealed SRCC with no lymphovascular invasion.

Conclusion

The scarcity of data on SRCCs emphasizes the need for ongoing research into the biology, diagnostics, and effective treatment options for patients with this disease, as responses to conventional therapies have been disappointing, leaving patients with few options. Cytoreductive nephrectomy for SRCC patients with metastatic disease is debatable, although some research suggests resection at any stage in patients with good performance status. In this case, radical nephrectomy was performed and there was no evidence of metastasis.

Magnetic resonance imaging (MRI) helps differentiate renal cell carcinoma with sarcomatoid differentiation from renal cell carcinoma without sarcomatoid differentiation

PURPOSE

The aim of the present study is to identify predictive imaging findings and construct a diagnostic model for differentiating renal cell carcinoma (RCC) with and without sarcomatoid dedifferentiation (sRCC and non-sRCC).

METHODS

This study is a single-center retrospective study. All patients had magnetic resonance imaging (MRI) with gradient-echo T1-weighted images, single-shot T2-weighted images (T2WI), and enhanced nephrographic phase images. Forty pathologically confirmed sRCCs and 80 non-sRCCs were included in this study. Control cases were selected by matching the tumor diameter and the year of MRI. Two radiologists independently evaluated the following findings: growth pattern, presence of low-intensity area on T2WI in the tumor (T2LIA), presence of non-enhancing area, local tumor stage, and presence of regional lymphadenopathy. Two radiologists measured the diameter of the tumor, T2LIA, and the non-enhancing area. Multivariable logistic regression analysis was used to identify independent predictive factors for differentiating sRCC from non-sRCC. Selected variables were entered in the logistic regression model, and the area under the curve (AUC) was calculated for each reader with 95% confidence intervals (CIs).

RESULTS

Larger T2LIA-to-tumor diameter ratio, regional lymphadenopathy, and local tumor stage 4 were associated with sRCC, and selected for the subsequent construction of a logistic regression model. With this model, the AUCs were 0.76 (95% CI, 0.66-0.85) and 0.70 (95% CI, 0.59-0.81) for prediction of sRCC.

CONCLUSION

In conclusion, larger T2LIA-to-tumor diameter ratio, regional lymphadenopathy, and local tumor stage 4 are predictive findings of sRCC. As a result, the model constructed using these findings demonstrated a moderate degree of diagnostic accuracy.

The Role of Cytoreductive Nephrectomy and Targeted Therapy on Outcomes of Patients With Metastatic Sarcomatoid Renal Cell Carcinoma: A Population-Based Analysis

Sarcomatoid renal cell carcinoma (sRCC) is a rare but aggressive form of kidney cancer with a poor prognosis. Despite recent advances in therapies for kidney cancers, an effective management strategy for sRCC is uncertain. We evaluated the impact of targeted therapy and cytoreductive nephrectomy (CN) on survival outcomes of patients with metastatic sRCC. We identified patients diagnosed with sRCC between January 1, 1973, and December 31, 2014, within the Surveillance, Epidemiology and End Results (SEER) database. Patients with metastatic sRCC were stratified based on the era of diagnosis (before or after the introduction of targeted systemic therapy in 2006) and the status of CN. Cancer-specific survival (CSS) and overall survival (OS) were analyzed. Data of 993 patients with metastatic sRCC were available for analysis. The median age was 62 years. Most patients were male (69%), Caucasian (71%), and were diagnosed in the targeted therapy era (83%); 53% of patients underwent CN. CSS and OS of the whole cohort were 5.0 months and 4.0 months, respectively. While the introduction of targeted therapy did not improve outcomes, CN improved CSS and OS in both pre-targeted therapy and targeted therapy era. On multivariable analysis, CN was a predictor of an improved CSS (hazard ratio [HR] 0.54, p < 0.0001) and OS (HR 0.51, p < 0.0001). Among other factors, older age at diagnosis, higher T stages, and node positivity were associated with worse outcomes. Our results showed that the introduction of targeted therapy did not improve outcomes in patients with metastatic sRCC. CN improved survival in both pre-targeted and targeted therapy eras.

Selection of Optimal Candidates for Cytoreductive Nephrectomy in Patients with Metastatic Clear Cell Renal Cell Carcinoma: A Predictive Model Based on SEER Database

Background

Currently, the progress of targeted drugs in the treatment of metastatic clear cell renal cell carcinoma (mccRCC) is limited. Cytoreductive nephrectomy (CN), as an alternative treatment, can improve the prognosis of patients with metastatic renal cell carcinoma to some extent. However, it is unclear which patients would benefit from this tumor reduction operation. As a consequence, we developed a predictive model to identify patients who may well benefit from CN in terms of survival.

Methods

We identified patients with metastatic clear cell renal cell carcinoma retrospectively from the Surveillance, Epidemiology, and End Results (SEER) database (2010–2015) and classified them into surgery and non-surgery groups. Propensity score matching (PSM) was performed to balance the baseline characteristics. Patients who survived longer than the median overall survival (OS) of no-surgery group were defined as surgical-benefit patients. Then, we developed a predictive model based on preoperative characteristics using multivariable Logistic regression. Calibration curves and the area under the receiver operating characteristic (AUC) were used to evaluate the efficiency of the predictive model. The clinical value of the nomogram was assessed utilizing decision curve analysis (DCA).

Results

Our study collected 5544 patients from the SEER database, with 2352(42.4%) receiving cytoreductive surgery. Overall survival (OS) was longer in the CN group than in the non-surgery group after 1:1 propensity scoring matching (median OS: 19 months vs 7 months; hazard ratio (HR) =0.4106, P< 0.001). In the matched surgery group, 65.7% (367) patients survived more than 7 months after the operation and they were considered to benefit from CN. The predictive model performed well on both the training group (AUC=73.4%) and the validation group (AUC=71.9%) and the calibration curves indicated a high degree of consistency. The decision curve analysis curve demonstrated the clinical utility. We classified surgical patients into the beneficial group and non-beneficial group by using the predictive model, then discovered a substantial difference in OS between the two groups.

Conclusions

We developed a nomogram to select ideal mccRCC patients who might benefit from cytoreductive nephrectomy. Clinicians could make a more precise treatment strategy for mccRCC patients.

Sarcomatoid Renal Cell Carcinoma: The Present and Future of Treatment Paradigms

Sarcomatoid renal cell carcinoma (sRCC) is an aggressive form of kidney cancer that is associated with poor prognosis. It can arise from any histologic type of renal cell carcinoma. The majority of cases will present with advanced or metastatic disease requiring systemic therapy. Nephrectomy is the treatment of choice in locally resectable disease. The therapeutic options for sRCC have evolved in the past decade. Cytotoxic chemotherapy and monotherapy with targeted therapy (VEGF and mTOR) have historically shown poor response rates and survival in the treatment of metastatic sRCC. The use of checkpoint inhibitors and their combination with targeted therapy against VEGF has changed the landscape and outcomes for renal cell carcinoma. Given the rarity of sRCC most of the data on treatment is from small cohorts or extrapolation from larger clinical trials. The benefit from the combination of checkpoint inhibitors and targeted therapy to VEGF has shown promise in the sRCC population in post hoc analysis of large clinical trials. Future research focusing on further characterizing the unique biologic and clinical features of sRCC is critical in advancing the knowledge and developing effective therapy to improve clinical outcomes and survival.

Can we identify a preferred first-line strategy for sarcomatoid renal cell carcinoma? A network meta-analysis

Background: Combinations based on immune checkpoint inhibitors are the new first-line standard treatment for metastatic renal cell carcinoma. Sarcomatoid renal cell carcinoma (sRCC) has a dismal prognosis but good immunogenicity. Methods: The authors performed a network meta-analysis of Phase III randomized trials of immune checkpoint inhibitor-based combinations versus standard tyrosine kinase inhibitor monotherapy reporting data for sRCC. The endpoints were overall survival, progression-free survival and objective response rate. Results: Five trials comprising 569 sRCC patients (out of a total of 4409 metastatic renal cell carcinoma patients) were included. Nivolumab-cabozantinib was the highest ranking treatment for overall survival (p-value = 88%) and progression-free survival (p-value = 81%). Atezolizumab-bevacizumab had the highest rank for objective response rate (p-value = 80%). Conclusion: Despite some limitations, nivolumab-cabozantinib might be the preferred first-line option for sRCC in terms of efficacy.

Durable Remission with Immunotherapy in a Patient with Sarcomatoid Renal Cell Carcinoma

Sarcomatoid differentiation is a rare and aggressive histologic subtype with poor prognosis, seen in several malignancies. In sarcomatoid renal cell carcinoma (RCC), the degree of sarcomatoid differentiation and the stage at presentation determines the prognosis. Despite resection, chemotherapy and targeted therapy response is modest, with relapse usually occurring within a few months. We present a case of a gentleman with sarcomatoid RCC managed with pembrolizumab, who has had no evidence of recurrence for over 4 years since the last dose of immunotherapy. RCCs with sarcomatoid differentiation have a high presence of programmed cell death protein 1 and programmed cell death ligand 1 in T cells and tumor cells, respectively, making immunotherapy an attractive option in this setting. Clinical trials are ongoing to further define the benefit of immunotherapy in sarcomatoid RCC.

Lenvatinib with or Without Everolimus in Patients with Metastatic Renal Cell Carcinoma After Immune Checkpoint Inhibitors and Vascular Endothelial Growth Factor Receptor-Tyrosine Kinase Inhibitor Therapies

INTRODUCTION

Lenvatinib (Len) plus everolimus (Eve) is an approved therapy for metastatic renal cell carcinoma (mRCC) after first-line vascular endothelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs), but limited data exist on the efficacy of Len ± Eve after progression on immune checkpoint inhibitors (ICIs) and VEGFR-TKIs.

METHODS

We retrospectively reviewed the records of patients with mRCC at our institution who were treated with Len ± Eve after ICI and VEGFR-TKI. A blinded radiologist assessed objective response as defined by RECIST version 1.1. Descriptive statistics and the Kaplan-Meier method were used.

RESULTS

Fifty-five patients were included in the analysis. Of these patients, 81.8% had clear-cell histology (ccRCC), and 76.4% had International Metastatic RCC Database Consortium intermediate-risk disease. Median number of prior therapies was four (range, 2-10); all patients had prior ICIs and VEGFR-TKIs, and 80% were previously treated with ICI and at least two VEGFR-TKIs, including cabozantinib. One patient (1.8%) achieved a complete response, and 11 patients (20.0%) achieved a partial response, for an overall response rate (ORR) of 21.8%; 35 patients (63.6%) achieved stable disease. In all patients, median progression-free survival (PFS) was 6.2 months (95% confidence interval [CI], 4.8-9.4) and median overall survival (OS) was 12.1 months (95% CI, 8.8-16.0). In patients with ccRCC, ORR was 24.4%, PFS was 7.1 months (95% CI, 5.0-10.5), and OS was 11.7 months (95% CI, 7.9-16.1). 50.9% of patients required dose reductions and 7.3% discontinued treatment because of toxicity.

CONCLUSION

Len ± Eve demonstrated meaningful clinical activity and tolerability in heavily pretreated patients with mRCC after disease progression with prior ICIs and VEGFR-TKIs.

IMPLICATIONS FOR PRACTICE

As the therapeutic landscape for patients with metastatic renal cell carcinoma continues to evolve, this single-center, retrospective review highlights the real-world efficacy of lenvatinib with or without everolimus in heavily pretreated patients. This article supports the use of lenvatinib with or without everolimus as a viable salvage strategy for patients whose disease progresses after treatment with immune checkpoint inhibitors and vascular endothelial growth factor receptor-tyrosine kinase inhibitor therapies, including cabozantinib.

Novel risk scoring system for metastatic renal cell carcinoma patients treated with cabozantinib

BACKGROUND

Cabozantinib is an effective treatment for metastatic renal cell carcinoma (mRCC). The international mRCC database consortium (IMDC) criteria is the gold standard for risk stratification in mRCC. We created a risk scoring system specific for mRCC patients treated with cabozantinib.

METHODS

We conducted a retrospective review of 87 patients with mRCC treated with cabozantinib at Winship Cancer Institute from 2015 to 2019. Overall survival (OS) and progression free survival (PFS) were used to measure clinical outcomes. Upon variable selection in multivariable analysis (MVA), elevated baseline monocyte-to-lymphocyte ratio (MLR), sarcomatoid histologic component, ECOG PS > 1, and absence of bone metastases were each assigned 1 point. A three-group risk scoring system was then created: low (score=0-1), intermediate (score=2), and high risk (score=3-4). The Cox proportional hazard model and Kaplan-Meier method were used for survival analyses.

RESULTS

The median age was 62 years-old and the majority were males (71%) with clear-cell RCC (75%). Most (67%) received at least 1 prior line of systemic therapy. High risk and intermediate risk pts had significantly shorter OS (high risk HR: 13.84, p<0.001; intermediate risk HR: 3.50, p = 0.004) and PFS (high risk HR: 7.31, p<0.001; intermediate risk HR: 1.87, p = 0.053) compared to low risk patients in MVA.

CONCLUSIONS

RCC patients treated with cabozantinib may benefit from specific risk stratification criteria using RCC histology, ECOG PS, sites of metastatic disease, and MLR. These variables are easily accessible in the clinical setting and may be helpful to determine which mRCC patients may benefit from treatment with cabozantinib.

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.

Systemic Therapies for the Management of Non-Clear Cell Renal Cell Carcinoma: What Works, What Doesn't, and What the Future Holds

Non-clear cell renal cell carcinoma (nccRCC) is a broad term that refers to a diverse group of tumors, each with its own distinct biologic and therapeutic profile. The management of nccRCCs is often based on extrapolating data from clinical trials in the more common clear cell renal cell carcinoma, but our emerging prospective and retrospective clinical experience in nccRCC allows us to make more precise recommendations tailored to each histology. The systemic therapy options for metastatic nccRCC include targeted therapies such as tyrosine kinase inhibitors, immune checkpoint inhibitors, and, for specific rare subtypes, cytotoxic chemotherapy. Each nccRCC histology may respond differently to these regimens, which makes accurate pathologic diagnosis imperative. In the present review, we discuss the available clinical and biological data that can help guide systemic therapy recommendations for specific nccRCC subtypes.

Dissecting Outcomes: Should Cytoreductive Nephrectomy Be Performed for Patients With Metastatic Renal Cell Carcinoma With Sarcomatoid Dedifferentiation?

Background

It is highly contested whether cytoreductive nephrectomy for treating advanced renal cell carcinoma (RCC) with sarcomatoid features (sRCC) benefits overall survival. Patients with sRCC are known to have a poor prognosis, and these tumors have a more aggressive biology than those without sarcomatoid features.

Methods

Patients with clear cell RCC or non–clear cell RCC underwent cytoreductive nephrectomy in efforts to improve overall survival (OS). Patients were stratified by presence or absence of histologic sarcomatoid features within tumor samples.

Results

Of 167 patients who underwent cytoreductive nephrectomy, 127 had clear cell RCC, of whom 14 had sarcomatoid features, and 40 had non–clear cell RCC, of whom 13 had sarcomatoid features. Median age of the cohort was 62 years (range, 56.5–69 years). The cohort included 119 male (71.3%) and 48 (28.7%) female patients. Among all patients with advanced RCC, having sRCC had a significantly worse OS after cytoreductive nephrectomy (30 vs 8 months; hazard ratio [HR], 2.88; P <0.0001). Additionally, favorable-risk patients had significantly longer OS compared to intermediate- or poor-risk patients (56 vs 30 vs 10 months; HR, 0.21; P =0.00016). For patients with clear cell RCC, having sRCC conferred a significantly poorer survival (30 vs 9 months; HR, 2.82; P=0.0035). Patients with non–clear cell sRCC also had significantly worse outcomes compared to patients whose tumors did not have sarcomatoid features (30 vs 6.5 months; HR, 3; P =0.009). When patients with sRCC were stratified by whether there was >10% or ≤10% sarcomatoid features present within the sample, there was no significant difference in OS (8 vs 8.5 months; P =0.32).

Conclusions

Sarcomatoid features within tumor histology confer significantly poor prognosis. Patients with sRCC, regardless of clear cell vs non–clear cell histology, have significantly shorter OS. Even among patients with 10% or less sarcomatoid features, there was no OS benefit to cytoreductive nephrectomy. Based on our findings, there appears to be a limited to no role of cytoreductive nephrectomy if sRCC is identified on pretreatment biopsy. The role of radiomics and pre-operative biopsies may confer significant benefit in this patient population.

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.

Outcomes of patients with metastatic renal cell carcinoma with sarcomatoid dedifferentiation to immune checkpoint inhibitors

INTRODUCTION

Metastatic renal cell carcinoma with sarcomatoid dedifferentiation (sRCC) is associated with poor survival outcomes. We aimed to analyze the efficacy and safety of immune checkpoint inhibitors (ICI) in patients with sRCC comparing clear-cell (sccRCC) to non-clear cell epithelial histology (snccRCC).

METHODS

We performed retrospective analysis of sRCC patients who received ICI at MD Anderson Cancer Center (n = 48, 41 with ccRCC and 7 with nccRCC) to determine the overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Additionally, we performed a prespecified multivariable Cox regression comparing survival outcomes between sccRCC and snccRCC.

RESULTS

The ORR for the entire cohort was 35.4% (95% confidence interval [CI]: 23.4%, 49.6%), including 8 (16.7%) patients (95% CI: 8.7%, 29.6%) who achieved a complete remission. The disease control rate was 52% (95% CI: 38.3%, 65.5%). In patients with sccRCC, the ORR was 39% (95% CI: 25.7%, 54.3%) and disease control rate 58.5% (43.4%, 72.2%). Among 7 snccRCC patients, only one (14.3%) achieved an objective partial response. At a median follow-up of 51.1 months, the median PFS was 4.9 months (95% CI: 2.7, 16.3) and the median OS was 28.4 months (95% CI: 15.8, NA) for the entire cohort. For patients with sccRCC, the median PFS was 8.9 months, with median OS of 30.1 months, compared with median PFS of 2.3 months (HR 0.25 [95% CI: 0.08, 0.78]; P= 0.0145) and median OS of 6.7 months (HR 0.13 [95% CI 0.04, 0.44]; P=0.0009) for patients with snccRCC.

CONCLUSION

ICIs appear to be effective in sccRCC while the treatment of snccRCC remains challenging.

Sarcomatoid renal cell carcinoma: biology, natural history and management

Sarcomatoid dedifferentiation is an uncommon feature that can occur in most histological subtypes of renal cell carcinomas (RCCs) and carries a decidedly poor prognosis. Historically, conventional treatments for sarcomatoid RCCs (sRCCs) have shown little efficacy, and median survival is commonly 6–13 months. Despite being first described in 1968, the mechanisms driving sarcomatoid dedifferentiation remain poorly understood, and information and treatment options available to physicians and patients are limited. When diagnosed at an early stage, surgical intervention remains the treatment of choice. However, preoperative identification through routine imaging or biopsy is unreliable and most patients present with advanced disease and systemic symptoms. For these patients, the role of cytoreductive nephrectomy is disputed. The expansion of immunotherapies approved for RCCs has generated a search for biomarkers that might be indicative of treatment response in sRCCs, although a proven effective systemic agent remains elusive. PDL1 expression is increased in sarcomatoid dedifferentiated renal tumours, which suggests that patients with sRCCs could benefit from PD1 and/or PDL1 immune checkpoint blockade therapy. Treatment outcomes for sarcomatoid tumours have remained relatively consistent compared with other RCCs, but further investigation of the tumour–immune cell microenvironment might yield insights into further therapeutic possibilities.

In this Review, Blum et al. summarize the current knowledge on sarcomatoid renal cell carcinoma, a diagnosis characterized by the presence of sarcomatoid dedifferentiation and a poor prognosis. They discuss the origin, presentation, molecular biology and treatment of this disease.

Sarcomatoid dedifferentiation is not considered to be a unique histological subtype of renal cell carcinomas (RCCs); rather, it can be present within any subtype of RCCs.

Sarcomatoid dedifferentiation appears in ~4% of all RCCs, but is present in ~20% of all metastatic RCCs. According to WHO guidelines, any RCC with sarcomatoid dedifferentiation is a WHO–International Society of Urological Pathology grade 4 lesion.

Sarcomatoid dedifferentiation is often heterogeneously present within RCCs, making routine imaging and biopsy unreliable for preoperative detection. Surgical resection for localized disease is the standard of care, with subsequent close monitoring of patients following surgery.

In patients with metastatic disease, conventional therapies such as surgery and systemic agents have been ineffective and overall 5-year survival remains at 23.5–33%.

Previous genomic analyses have failed to identify definitive mutational drivers of disease. However, sarcomatoid RCCs (sRCCs) have been shown to have higher PD1 and PDL1 expression than other subtypes of RCCs. Newer combinations of immune checkpoint inhibitor immunotherapies could yield improved responses and outcomes.

Studies investigating sRCCs are limited by patient numbers owing to the low incidence of sRCCs and their advanced stage at presentation. Multi-institutional efforts to establish a consensus on treatment recommendations based on highly powered data are essential.

Prognostic and Predictive Factors in Metastatic Renal Cell Carcinoma: Current Perspective and a Look Into the Future

Metastatic renal cell carcinoma (mRCC) comprises a highly heterogeneous group of diseases with varied clinical outcomes. As a result, models to estimate prognosis were developed in an attempt to aid patient counseling, treatment selection, and clinical trial design. Contemporary prognostic models have been mostly generated based on clinical factors because of their ease of use. Recent advances in molecular techniques have allowed unprecedented molecular profiling of RCC and the discovery of genomic and proteotranscriptomic factors that may contribute to disease trajectory. With the advent of multiple systemic therapies in mRCC in recent years, predictive biomarkers have become increasingly relevant in treatment selection. In this review, we discuss the existing staging systems and prognostic models in mRCC. We also highlight various promising molecular biomarkers according to the subtypes of RCC and explore their integration into the traditional prognostic models. In addition, we discuss emerging predictive biomarkers in the era of immuno-oncology. Lastly, we explore future directions with a focus on liquid biopsies and composite biomarkers.

Efficacy and Safety of Nivolumab Plus Ipilimumab versus Sunitinib in First-line Treatment of Patients with Advanced Sarcomatoid Renal Cell Carcinoma

PURPOSE

Patients with advanced renal cell carcinoma with sarcomatoid features (sRCC) have poor prognoses and suboptimal outcomes with targeted therapy. This post hoc analysis of the phase III CheckMate 214 trial analyzed the efficacy of nivolumab plus ipilimumab (NIVO+IPI) versus sunitinib in patients with sRCC.

PATIENTS AND METHODS

Patients with sRCC were identified via independent central pathology review of archival tumor tissue or histologic classification per local pathology report. Patients were randomized 1:1 to receive nivolumab (3 mg/kg) plus ipilimumab (1 mg/kg) every 3 weeks (four doses) then nivolumab 3 mg/kg every 2 weeks, or sunitinib 50 mg orally every day (4 weeks; 6-week cycles). Outcomes in patients with sRCC were not prespecified. Endpoints in patients with sRCC and International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor-risk disease included overall survival (OS), progression-free survival (PFS) per independent radiology review, and objective response rate (ORR) per RECIST v1.1. Safety outcomes used descriptive statistics.

RESULTS

Of 1,096 randomized patients in CheckMate 214, 139 patients with sRCC and intermediate/poor-risk disease and six with favorable-risk disease were identified. With 42 months' minimum follow-up in patients with sRCC and intermediate/poor-risk disease, median OS [95% confidence interval (CI)] favored NIVO+IPI [not reached (NR) (25.2-not estimable [NE]); n = 74] versus sunitinib [14.2 months (9.3-22.9); n = 65; HR, 0.45 (95% CI, 0.3-0.7; P = 0.0004)]; PFS benefits with NIVO+IPI were similarly observed [median 26.5 vs. 5.1 months; HR, 0.54 (95% CI, 0.33-0.86; P = 0.0093)]. Confirmed ORR was 60.8% with NIVO+IPI versus 23.1% with sunitinib, with complete response rates of 18.9% versus 3.1%, respectively. No new safety signals emerged.

CONCLUSIONS

NIVO+IPI showed unprecedented long-term survival, response, and complete response benefits versus sunitinib in previously untreated patients with sRCC and intermediate/poor-risk disease, supporting the use of first-line NIVO+IPI for this population.See related commentary by Hwang et al., p. 5.

A Population Study to Identify Candidates for Cytoreductive Nephrectomy in Patients with Metastatic Sarcomatoid Renal Cell Carcinoma from the Surveillance, Epidemiology, and End Results (SEER) Database

BACKGROUND This population study aimed to identify suitable candidates for cytoreductive nephrectomy in patients with metastatic sarcomatoid renal cell carcinoma (RCC) from the US Surveillance, Epidemiology, and End Results (SEER) database. MATERIAL AND METHODS Demographic and clinical data from 1,229 patients with metastatic sarcomatoid RCC were retrieved from the SEER database. Patients were divided into the cytoreductive nephrectomy group (n=937) and the no surgery group (n=292). Multivariate Cox regression analysis identified factors associated with overall survival (OS) and propensity score matching identified factors that significantly impacted the OS. Survival of propensity score-matched subgroups of patients with metastatic sarcomatoid RCC treated by cytoreductive nephrectomy or no surgery was determined by the Kaplan-Meier method and compared by the log-rank test. RESULTS Of the 1,229 patients with metastatic sarcomatoid RCC retrieved from the SEER database, age, tumor size, T stage, and N stage were independent risk factors for patient survival. There were no significant differences in age, N stage, and tumor size between the cytoreductive nephrectomy-treated and non-surgically treated T stage cases following propensity score matching. OS benefits were found in cases with stage T1 (12 months increase), T2 (7.5 months increase), T3a (2 months increase), and T4 (3 months increase), but not in the T3b or T3c subgroups treated by cytoreductive nephrectomy, compared with patients with no surgical treatment. CONCLUSIONS Data from the SEER database showed that cytoreductive nephrectomy improved OS in patients with T1 and T2 metastatic sarcomatoid RCC with a significant long-term survival benefit of >6 months.

[SMALL RENAL CELL CARCINOMA PRESENTING WITH HUGE SACRALMETASTASIS: A CASE REPORT]

A 66-year-old man with buttock pain and intermittent claudication visited a nearby doctor. Magnetic resonance imaging revealed a tumor of 8 cm in diameter in his sacrum. He was referred to our hospital. Abdominal contrast enhanced computed tomography revealed a small mass of 2.5 cm in diameter on his left kidney and he was diagnosed with metastatic bone disease after needle tumor biopsy. However, needle biopsy of the renal tumor demonstrated no evidence of malignancy. As he rejected further examination, we started treatment using the tyrosine kinase inhibitor sunitinib. However, it had little effect on his sacral metastasis and he developed massive bowel bleeding twice. Extensive invasion from the sacral metastasis to the back side of the rectum was found on colonoscopy. The patient died 2 months after the introduction of sunitinib. The final diagnosis based on pathological autopsy was renal cell carcinoma with sacral metastasis.

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.

Impact of sarcomatoid differentiation and rhabdoid differentiation on prognosis for renal cell carcinoma with vena caval tumour thrombus treated surgically

Background

Sarcomatoid differentiation in renal cell carcinoma (RCC) with vena caval tumour thrombus has been shown to be associated with aggressive behaviours and poor prognosis; however, evidence of the impact of rhabdoid differentiation on prognosis is lacking. This study evaluated the impact of sarcomatoid differentiation and rhabdoid differentiation on oncological outcomes for RCC with vena caval tumour thrombus treated surgically.

Methods

We retrospectively analysed patients treated surgically for RCC with vena caval tumour thrombus at our institute from Jan 2015 to Nov 2018. Prognostic variables were evaluated for associations with progression-free survival (PFS) and cancer-specific survival (CSS) by Kaplan–Meier survival analysis and log-rank test. Univariate and multivariate analyses were performed to determine independent prognostic variables.

Results

We identified 125 patients with RCC and vena caval tumour thrombus, including 17 (13.6%) with sarcomatoid differentiation alone, 8 (6.4%) with rhabdoid differentiation alone and 3 (2.4%) with both sarcomatoid and rhabdoid differentiation. Compared to pure RCC, patients with sarcomatoid differentiation but not rhabdoid differentiation have worse PFS (p = 0.018 and p = 0.095, respectively). The univariate and multivariate analyses both showed sarcomatoid differentiation as a significant predictor of PFS. Compared to pure RCC, patients with sarcomatoid differentiation (p = 0.002) and rhabdoid differentiation (p = 0.001) both had significantly worse CSS. The univariate analysis showed sarcomatoid differentiation, rhabdoid differentiation, metastasis and blood transfusion as significant predictors of CSS (All, p < 0.05). In the multivariate analysis, sarcomatoid differentiation (HR 3.90, p = 0.008), rhabdoid differentiation (HR 3.01, p = 0.042), metastasis (HR 3.87, p = 0.004) and blood transfusion (HR 1.34, p = 0.041) all remained independent predictors of CSS.

Conclusions

Sarcomatoid differentiation and rhabdoid differentiation are both independent predictors of poor prognosis in RCC with vena caval tumour thrombus treated surgically.

Analysis of the factors influencing the survival time of patients with sarcomatoid renal cell carcinoma

The aim of the present study was to identify the factors influencing the survival time of patients with sarcomatoid renal cell carcinoma (SRCC). Between January 2000 and September 2017, a total of 21 patients were enrolled, all of whom were diagnosed with SRCC. In total, eight prognostic factors were analyzed using the Kaplan-Meier estimator, a log-rank test and Cox's proportional hazards model. The log-rank test results revealed that there was a significant association between the proportion of sarcoma elements and survival time of patients with SRCC (P<0.05). In addition, there was a significant association between post-operative drug treatment and SRCC survival time (P<0.05). The results of the Kaplan-Meier estimate demonstrated that the survival curve of post-operative drug treatment was significantly greater compared with the survival curve of patients who did not undergo drug treatment (P<0.05). The survival curve of patients with a proportion of sarcoma elements <50% was significantly greater compared with the survival curve of patients with a proportion of sarcoma elements ≥50% (P<0.05). Furthermore, the Cox's proportional hazards model revealed that the mortality risk in post-operative patients without drug treatment was 5.822 times greater compared with that of patients with drug treatment (P<0.05). Mortality risk in patients with a proportion of sarcoma elements ≥50% was 4.682 times higher compared with that of patients with sarcoma elements <50% (P<0.05). Finally, post-operative drug therapy was revealed to be a protective factor which significantly affected the survival time of patients with SRCC [risk ratio (RR)=0.172], in addition to the proportion of sarcoma elements ≥50% (RR=4.682). In conclusion, drug therapy should be promoted upon patient diagnosis with SRCC and attention should be given to the proportion of sarcomatoid components.

Retrospective review of experience with sarcomatoid renal cell carcinoma: Multimodality treatment remains an unmet goal

Background:

Sarcomatoid change in Renal cell carcinoma(RCC) is associated with adverse outcomes with median survival of 6 months.

Settings and Design:

This is a retrospective study of patients diagnosed of sarcomatoid RCC(sRCC) between 2007 and 2013 which were followed up till 2017.

Methods and Material:

Patients (n=22) were grouped based on whether they received additional chemotherapy following nephrectomy. Two groups were followed up until 2017 and overall survival was record. Overall survival curves were estimated by Kaplan-Meier method and compared using Log Rank (Mantel-Cox) test between two groups.

Statistical analysis used:

Kaplan-Meier method and Log Rank (Mantel-Cox) test.

Results:

The patients who had chemotherapy had 13.4 cm of mean tumour size with a mean survival of 20.4 ± 8.3 months. The patients who did not undergo chemotherapy had mean tumour size of 11.7 cm with a mean survival of 21 ± 5.9 months. There was no much statistical difference between the two groups in OS with P value = 0.99.

Conclusion:

The current adjuvant chemotherapy used in sRCC patients who develop metastasis gives no survival advantage.

Ki-67 index and percentage of sarcomatoid differentiation were two independent prognostic predictors in sarcomatoid renal cell carcinoma

Purpose

To identify whether and which of pathological features of sarcomatoid differentiation (SD) in renal cell carcinoma (RCC) can be used as independent predictors associated with overall survival (OS).

Materials and methods

After institutional review board approval, patients with a diagnosis of sarcomatoid RCC (sRCC), spindled RCC, or RCC with the presence of spindle cells between 2003 and 2017 were further selected and re-examined. The primary pathological features including histological subtypes, tumor necrosis, Ki-67 index of SD, and the percent of SD (%SD) were included into analysis. Histological subtypes were categorized into clear-cell RCC and nonclear-cell RCC. Ki-67 index of SD was confirmed by immunohistochemical staining. %SD was estimated through reviewing all of the tumor sections microscopically and then giving an approximate %SD within the entire tumor. The clinical relevant prognostic predictor's association with OS was analyzed within Cox proportional hazards regression models. Survival curves were generated using the Kaplan-Meier method, and OS differences were compared using the log-rank test.

Results

A total of 2,089 consecutive patients of RCC were referred to our department, of whom 62 (3.0%) patients were identified with histological element of SD after re-examining the available slides of suspicious cases. Finally, 53 patients were included into survival analysis after excluding 9 patients without adequate information. Thirty-eight (71.7%) patients died at last follow-up. The median OS for all patients was 11.0 months from the date of surgery. In patients with clinical distant metastasis (cM₁), the median OS was only 3 compared with 21 months for patients with no clinical distant metastasis (cM₀). Tumor stage, status of clinical distant metastasis, Ki-67 index, and %SD were independent predictors of multivariate analysis in overall 53 patients. However, in the cohort of cM₀ patients, we found that only %SD and Ki-67 index were two independent predictors of OS in multivariate analysis.

Conclusion

Patients with sRCC are associated with very poor prognosis. Ki-67 index of SD and %SD were identified as the two most important independent predictors particularly for nonmetastatic patients. The limitations of our study were also observed, and further studies are needed.

Epidemiology, biology and treatment of sarcomatoid RCC: current state of the art

Long recognized to confer an extremely poor prognosis, sarcomatoid dedifferentiation of renal cell carcinoma (sRCC) is a tumor phenotype that is finally beginning to be better understood on the molecular and genetic levels. With an overall incidence that ranges from 1 to 32% depending on associated RCC subtype, the survival of sarcomatoid RCC patients rarely exceeds 2 years. The main reasons for its poor outcome include its aggressive biology, its tendency to present at an advanced or metastatic stage at the time of diagnosis, its high rate of tumor recurrence after nephrectomy, and its limited response to systemic therapies. Molecular pathology studies suggest that sarcomatoid dedifferentiation originates from a focal epithelial-mesenchymal transition (EMT) arising in the carcinomatous component of the tumor. It is hoped that the growing understanding of the molecular biology of sRCC will soon make it possible to adapt treatments based on the identification of actionable tumor alterations. The deliberate inclusion of these patients in the multicenter clinical trials of immune, targeted and combination therapies is a necessary next step in pioneering future treatment strategies.

Sarcomatoid Variant of Urothelial Carcinoma of the Renal Pelvis with Inferior Vena Cava Tumour Thrombus: A Case Report and Literature Review

Sarcomatoid variant of urothelial carcinoma (SVUC) of the renal pelvis is a rare entity. To the best of our knowledge, around 25 cases of this neoplasm have been reported in the literature to date, most of which were of high stage. The inferior vena cava tumour thrombus, which is a hallmark of renal cell carcinoma (RCC), may rarely be found in urothelial carcinoma of renal pelvis. In this report, a case of SVUC associated with tumour extension to inferior vena cava is documented. This association has been encountered in only one previously reported case. The possibility of urothelial carcinoma of the renal pelvis should therefore be included in the differential diagnosis of tumour thrombus of the inferior vena cava.

Sarcomatoid renal cell carcinoma: Biology and treatment advances

Sarcomatoid transformation in renal cell carcinoma, so called sacromatoid RCC (sRCC), is associated with an aggressive behavior and a poor prognosis. Current therapeutic approaches are largely ineffective. Recent studies looking into the genomic and molecular characterization of sRCCs have provided insights into the biology and pathogenesis of this entity. These advances in molecular signatures may help development of effective treatment strategies. We herein present a review of recent developments in the pathology, biology, and treatment modalities in sRCC.

Rapid recurrence and radiographic progression of sarcomatoid renal cell carcinoma

Sarcomatoid renal cell carcinoma (sRCC) is an aggressive variant of renal cell carcinoma (RCC) that has a significantly lower overall survival. Even after prompt surgical extirpation, this histologic variant progresses rapidly. We present a case of an early recurrence and rapid progression of sRCC despite successful radical resection.

Addressing the best treatment for non-clear cell renal cell carcinoma: A meta-analysis of randomised clinical trials comparing VEGFR-TKis versus mTORi-targeted therapies

AIM

Non-clear cell renal cell carcinoma (nccRCC) tumours include a heterogeneous group of malignancies that profoundly differ in terms of morphology, genetic profile, clinical behaviour and prognosis. The optimal treatment algorithm for nccRCC is still unknown and derived mainly from evidence available for ccRCC, being therefore represented by targeted agents against vascular endothelial growth factor and mammalian target of rapamycin (mTOR) pathways. We aimed to compare the efficacy of vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKis) and mTOR inhibitors (mTORi) for the treatment of nccRCC patients.

METHODS

Searching the MEDLINE/PubMed, Cochrane Library and American Society of Clinical Oncology Meeting abstracts prospective studies were identified. Data extraction was conduced according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The measured outcomes were progression-free survival (PFS), overall survival (OS) and the overall response rate (ORR).

RESULTS

Four randomised controlled trials were selected for final analysis, with a total of 332 patients evaluable for PFS. Treatment with TKi significantly reduced the risk of progression compared with mTORi (hazard ratio [HR] = 0.71; 95% confidence interval [CI] 0.60-0.84; p < 0.0001). This difference remained significant when sunitinib was compared with everolimus in first-line setting (HR = 0.67; 95% CI, 0.56-0.80; p < 0.00001). In the 332 patients evaluable for OS, no significant difference was found between TKi and mTORi (HR = 0.86; 95% CI, 0.67-1.12; p = 0.27). In the 176 evaluable patients, TKis therapy did not improve the ORR when compared with mTORi (relative risk [RR] = 2.21; 95% CI, 0.87-5.60; p = 0.09), even if treatment with sunitinib doubled the probability of achieving a tumour response.

CONCLUSIONS

Treatment with TKis significantly improves PFS, but not OS, when compared with mTORi. Moreover, sunitinib as first-line therapy reduces the risk of progression compared with everolimus; therefore, supporting the standard treatment paradigm broadly used for ccRCC patients. The relatively modest efficacy of available targeted therapies reinforces the need of future histology based, molecular driven therapeutic paradigm.