Sarcomatoid Dedifferentiation in Renal Cell Carcinoma: From Novel Molecular Insights to New Clinical Opportunities

Metastatic Kidney Cancer: Does the Location of the Metastases Matter? Moving towards Personalized Therapy for Metastatic Renal Cell Carcinoma

The management of renal cell carcinoma (RCC) has been revolutionized over the past two decades with several practice-changing treatments. Treatment for RCC often requires a multimodal approach: Local treatment, such as surgery or ablation, is typically recommended for patients with localized tumors, while stage IV cancers often require both local and systemic therapy. The treatment of advanced RCC heavily relies on immunotherapy and targeted therapy, which are highly contingent upon histological subtypes. Despite years of research on biomarkers for RCC, the standard of care is to choose systemic therapy based on the risk profile according to the International Metastatic RCC Database Consortium and Memorial Sloan Kettering Cancer Centre models. However, many questions still need to be answered. Should we consider metastatic sites when deciding on treatment options for metastatic RCC? How do we choose between dual immunotherapy and combinations of immunotherapy and tyrosine kinase inhibitors? This review article aims to answer these unresolved questions surrounding the concept of personalized medicine.

Sintilimab combined with axitinib in the treatment of advanced chromophobe renal cell carcinoma: a case report

Chromophobe renal cell carcinoma (ChRCC) is a rare pathological type of renal cell carcinoma (RCC). Related systematic studies involving large numbers of patients are lacking, and more importantly, there is currently no international consensus on post-line treatment guidelines for ChRCC. The rapid development of systemic treatment with molecular targeted therapies and immune checkpoint inhibitors has brought effective approaches for patients with clear cell renal cell carcinoma (ccRCC), while progress in the treatment of ChRCC is still limited. In this case report, the patient was initially diagnosed at the early stage; 4 years post-surgery, she developed lung metastases and the disease progressed once again after being treated with sunitinib monotherapy for 3 years. However, after combining the immunotherapy sintilimab with the targeted therapy axitinib as second-line treatment, imageological examination showed lesions in the lungs that gradually decreased, and the bone metastases remained stable. To date, the patient has been continuously treated for over 2 years and is still undergoing regular treatment and follow-up. This case is the first to report the long-term survival of metastatic disease by using this treatment regimen and to propose a potential therapeutic option for patients with metastatic ChRCC. Since only one case was observed in this report, further study is needed.

Sarcomatoid renal cell carcinoma with an inferior vena cava tumor thrombus that was completely resected by robot-assisted laparoscopic radical nephrectomy after neoadjuvant therapy nivolumab plus ipilimumab: a case report

We here present a patient with a sarcomatoid renal cell carcinoma complicated by inferior vena cava tumor thrombus that we treated with nivolumab plus ipilimumab. This resulted in shrinkage of the tumor, enabling complete resection by robot-assisted laparoscopic radical nephrectomy. The patient is still alive with no evidence of recurrence.

Do patients with metastatic renal cell carcinoma obtain survival benefits from cytoreductive nephrectomy? A population-based study

PURPOSE

This study aimed to explore the value of cytoreductive nephrectomy (CN) and develop nomograms to predict the prognosis of metastatic renal cell carcinoma (mRCC) patients with receiving radiology therapy or/and chemotherapy (RT/&CT).

METHODS

Clinical data of patients with mRCC between 2010 and 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Prognostic nomograms were constructed to predict the overall survival (OS) and cancer-specific survival (CSS) probability for 1-, 3-, and 5- years in patients with mRCC. A series of validation methods were used to validate the accuracy and reliability of the model, including area under the receiver operating curve (AUC), consistency index (C-index), calibration curve, and decision curve analysis (DCA).

RESULTS

1394 patients were enrolled in this study. All patients were randomly divided into the training cohort (n = 976) and the validation cohort (n = 418). In the training cohort, multivariate Cox regression analysis suggested that pathology grade, histology type, T stage, N stage, surgery, and distant metastasis were independent risk factors for OS and CSS. The AUC and C-index were both over 0.65 in both cohorts, indicating that the nomograms for OS and CSS had satisfactory discriminative power. The calibration curves revealed that the predictive nomograms had a good consistency between the observed and the predicted survival.

CONCLUSION

This study provided evidence that mRCC patients underwent RT/&CT could gain survival benefits from CN. The prognostic nomogram constructed in our study is reliable and practical, may help guide clinical strategies in the treatment of mRCC.

P53 and survivin expression in renal cell carcinoma

Objective

Mutation of p53 is detected in more than 50% of human cancers, expression of p53 has a potential prognostic value in patients with renal cell carcinoma (RCC). Survivin is a member of the inhibitor of apoptosis protein family, its overexpression is observed in many malignancies, including RCC. The aim of the study was to estimate a correlation between survivin and p53 expression in tumor samples and the histologic type of a tumor, tumor stage, tumor grade, and survival of patients.

Materials and Methods

Tumor samples were collected from surgical specimens of 90 patients who underwent radical or partial nephrectomy for RCC between November 2017 and July 2020. Tumors were staged according to the UICC (The Union for International Cancer Control) TNM classification system and histopathologically graded according to Fuhrman nuclear grade system. Histopathological diagnosis was confirmed with standard light microscopic evaluation, using hematoxylin and eosin staining and standard p53 and survivin antibodies.

Results

Positive p53 staining was observed in 36.7% of tumor specimens and 24.4% were survivin positive. There was a statistically significant correlation between p53 or survivin expression and histologic subtype of clear cell RCC as well as Type I and II of papillary RCC. There was a statistically significant correlation between p53 expression and tumor size, stage, and grade. The p53 or survivin expression was related to lower overall survival.

Conclusion

The results of this study suggest that p53 overexpression and survivin positivity in RCC patients could be associated with poor prognosis. Thus, these proteins could be used as prognostic markers in RCC.

The Role of Cytoreductive Nephrectomy in Renal Cell Carcinoma with Sarcomatoid Histology: A Case Series and Review of the Literature

Background: Renal cell carcinoma with sarcomatoid dedifferentiation represents a rare histological entity characterized by aggressive behavior, limited efficacy of tyrosine kinase inhibitors or mTOR inhibitors, and poor outcome. The immune checkpoint inhibitor therapy regimen combining ipilimumab with nivolumab represents a new standard of care for this patient population due to a hitherto unprecedented response rate and overall survival. On the other hand, the role of cytoreductive nephrectomy in metastatic renal cell carcinoma, in particular, with sarcomatoid histology, remains controversial. Patient and Methods: In the present case series, we report six patients with locally advanced or synchronous metastatic sarcomatoid renal cell carcinoma and intermediate or poor International Metastatic RCC Database Consortium (IMDC) risk score, five of whom were successfully subjected to cytoreductive nephrectomy. Results: All six patients received the combination regimen of ipilimumab with nivolumab. Five of these patients underwent upfront cytoreductive nephrectomy followed by systemic treatment without any significant delay, with a durable treatment outcome. Notably, two patients with poor prognostic features achieved a long-term major partial response to therapy. We also performed a review of the literature on optimal treatment strategies for patients with sarcomatoid renal cell carcinoma. Conclusion: Herein, we highlight the feasibility of performing cytoreductive nephrectomy in patients with intermediate/poor prognosis metastatic renal cell carcinoma with sarcomatoid dedifferentiation followed by immunotherapy with ipilimumab and nivolumab. To enhance the chances of immunotherapy success, cytoreductive nephrectomy should also be considered for patients presenting with a disease with adverse prognostic parameters.

Tumor-immune microenvironment revealed by Imaging Mass Cytometry in a metastatic sarcomatoid urothelial carcinoma with a prolonged response to pembrolizumab

Sarcomatoid urothelial carcinoma (SUC) is a rare subtype of urothelial carcinoma (UC) that typically presents at an advanced stage compared to more common variants of UC. Locally advanced and metastatic UC have a poor long-term survival following progression on first-line platinum-based chemotherapy. Antibodies directed against the programmed cell death 1 protein (PD-1) or its ligand (PD-L1) are now approved to be used in these scenarios. The need for reliable biomarkers for treatment stratification is still under research. Here, we present a novel case report of the first Imaging Mass Cytometry (IMC) analysis done in SUC to investigate the immune cell repertoire and PD-L1 expression in a patient who presented with metastatic SUC and experienced a prolonged response to the anti-PD1 immune checkpoint inhibitor pembrolizumab after progression on first-line chemotherapy. This case report provides an important platform for translating these findings to a larger cohort of UC and UC variants.

Renal cell carcinoma and viral infections: A dangerous relationship?

Virus-related cancers in humans are widely recognized, but in the case of renal cancer, the link with the world of viruses is not clearly established in humans, despite being known in animal biology. In the present review, we aimed to explore the literature on renal cell carcinoma (RCC) for a possible role of viruses in human RCC tumorigenesis and immune homeostasis, hypothesizing the contribution of viruses to the immunogenicity of this tumor. A scientific literature search was conducted using the PubMed, Web of Science, and Google Scholar databases with the keywords “virus” or “viruses” or “viral infection” matched with (“AND”) “renal cell carcinoma” or “kidney cancer” or “renal cancer” or “renal carcinoma” or “renal tumor” or “RCC”. The retrieved findings evidenced two main aspects testifying to the relationship between RCC and viruses: The presence of viruses within the tumor, especially in non-clear cell RCC cases, and RCC occurrence in cases with pre-existing chronic viral infections. Some retrieved translational and clinical data suggest the possible contribution of viruses, particularly Epstein-Barr virus, to the marked immunogenicity of sarcomatoid RCC. In addition, it was revealed the possible role of endogenous retrovirus reactivation in RCC oncogenesis, introducing new fascinating hypotheses about this tumor’s immunogenicity and likeliness of response to immune checkpoint inhibitors.

Potential Use of CTCs as Biomarkers in Renal Cancer Patients

We demonstrated that the CellCollector is an appropriate tool for detecting CTCs in RCC patients. We examined EpCAM and MUC1 expression levels in RCC tissues and cell lines and analyzed the detection rate of CTCs in blood samples ex vivo using an anti-EpCAM antibody-covered straight or spiraled CellCollector. Eight matched samples were examined for affinity to the anti-EpCAM vs. anti-EpCAM/anti-MUC1 antibody-covered wire. The use of this combination of antibodies allowed us to classify patients with lung metastasis. Finally, four patients were analyzed in vivo. In conclusion, both straight (ex vivo, in vivo) and spiraled (ex vivo) wires detected CTCs.

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.

Undifferentiated and dedifferentiated urological carcinomas: lessons learned from the recent developments

Loss of the morphological and immunophenotypic characteristics of a neoplasm is a well-known phenomenon in surgical pathology and occurs across different tumor types in almost all organs. This process may be either partial, characterized by transition from well differentiated to undifferentiated tumor component (=dedifferentiated carcinomas) or complete (=undifferentiated carcinomas). Diagnosis of undifferentiated carcinoma is significantly influenced by the extent of sampling. Although the concept of undifferentiated and dedifferentiated carcinoma has been well established for other organs (e.g. endometrium), it still has not been fully defined for urological carcinomas. Accordingly, undifferentiated/ dedifferentiated genitourinary carcinomas are typically lumped into the spectrum of poorly differentiated, sarcomatoid, or unclassified (NOS) carcinomas. In the kidney, dedifferentiation occurs across all subtypes of renal cell carcinoma (RCC), but certain genetically defined RCC types (SDH-, FH- and PBRM1- deficient RCC) seem to have inherent tendency to dedifferentiate. Histologically, the undifferentiated component displays variable combination of four patterns: spindle cells, pleomorphic giant cells, rhabdoid cells, and undifferentiated monomorphic cells with/without prominent osteoclastic giant cells. Any of these may occasionally be associated with heterologous mesenchymal component/s. Their immunophenotype is often simple with expression of vimentin and variably pankeratin or EMA. Precise subtyping of undifferentiated (urothelial versus RCC and the exact underlying RCC subtype) is best done by thorough sampling supplemented as necessary by immunohistochemistry (e.g. FH, SDHB, ALK) and/ or molecular studies. This review discusses the morphological and molecular genetic spectrum and the recent develoments on the topic of dedifferentiated and undifferentiated genitourinary carcinomas.

Anti-Vascular Endothelial Growth Factor C Antibodies Efficiently Inhibit the Growth of Experimental Clear Cell Renal Cell Carcinomas

Despite improvement during the last ten years in the longevity of patients with metastatic clear cell renal cell carcinoma (mccRCC) the disease remains incurable. Hence, new therapeutic strategies are urgently needed. Relapse following anti-angiogenic treatment depends on the over-expression of vascular endothelial growth factor C (VEGFC), one of the main drivers of lymphangiogenesis. Therefore, we developed specific mouse monoclonal antibodies and evaluated their therapeutic efficacy in vitro and in vivo. Immunization of mice with the domain of VEGFC that stimulates the VEGF receptor 3 (VEGFR3) led to the selection of one hybridoma producing specific anti-VEGFC monoclonal antibodies. The selected 1E9 antibodies were sequenced, and the corresponding variable light and heavy chains were subcloned into expression vectors in frame with sequences encoding the human IgG1 constant heavy and light chains. CHO cells were stably transfected and cloned to produce chimeric antibodies. These antibodies inhibited the activation of VEGFR3 signaling, and therefore the proliferation and migration of VEGFC-stimulated endothelial cells. Moreover, they inhibited the proliferation of VEGFC-expressing renal cancer cells through NRP2 signaling. 1E9 antibodies inhibited the growth of experimental RCC, and their therapeutic efficacy was enhanced by the anti-VEGF antibody bevacizumab. Hence, our results suggest that targeting VEGFC could have a relevant therapeutic impact on mccRCC that relapse following anti-angiogenic treatment.

Major pathological response after neoadjuvant immunotherapy in esophageal spindle cell carcinoma: A case report

Esophageal spindle cell carcinoma (ESpCC) is a rare subtype of esophageal carcinoma, accounting for 1% of all esophageal malignancies. The clinical outcome is unknown due to the lack of treatment options. Here, we present the case of a 60‐year‐old male with initially unresectable ESpCC, in which platinum‐based concurrent chemoradiotherapy was unsuccessful. He was subsequently treated with neoadjuvant immunotherapy and after surgery achieved a complete pathological response; therefore, neoadjuvant immunotherapy might be a novel option for ESpCC patients.

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.

Checking the Hippo in Sarcomatoid Renal Cell Carcinoma with Immunotherapy

Subset analysis of patients with sarcomatoid renal cell carcinoma (sRCC) included in the CheckMate 214 trial of ipilimumab-nivolumab versus sunitinib showed improved outcomes in sRCC with ipilimumab-nivolumab. The use of checkpoint inhibitor-based regimens in sRCC, for which therapeutic options were once limited, is further supported by additional clinical trials.See related article by Tannir et al., p. 78.

First-line axitinib therapy is less effective in metastatic renal cell carcinoma with spindle histology

Axitinib, a vascular endothelial growth factor receptor-tyrosine kinase inhibitor, will be used in combination first-line therapies against metastatic renal cell carcinoma (mRCC), but its effects as a first-line monotherapy are unclear. Thus, we aimed to elucidate pretreatment clinical factors that predict the prognosis of patients with mRCC receiving first-line axitinib therapy. We enrolled 63 patients with mRCC treated with axitinib as first-line therapy between Nov. 2003 and Jul. 2018. Progression-free survival (PFS) and overall survival (OS) were assessed using the Wald χ² statistic in Cox proportional hazards regression. Median patient age was 67 (range: 25-85) years. Seven (11.1%) patients were classified as being at favorable risk, 33 (52.4%) at intermediate risk, and 23 (36.5%) at poor risk according to the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk classification system. Median follow-up duration after axitinib initiation was 14 (range: 1-72) months. Median PFS and OS were 18 months and 65 months, respectively. Cox regression analyses of clinical predictors revealed that high C-reactive protein (CRP) levels were significantly correlated with shorter PFS [hazard ratio (HR), 1.63; 95% confidence interval (CI) 1.7-4.0)], whereas spindle cells and poor IMDC risk scores were related to worse OS (HR, 2.87 and 2.88, respectively; 95% CI 1.4-11.0 and 1.1-8.5, respectively). Thus, patients with mRCC and spindle histology or poor IMDC risk scores had worse OS, and those with high CRP levels had shorter PFS in first-line axitinib treatment. Other therapies might be more suitable for initial management of such patients.

Chromophobe renal cell carcinoma: current and controversial issues

It has been 35 years since Professor Thoenes and his colleagues discovered chromophobe renal cell carcinoma (RCC). Since then, our knowledge about this tumour entity has changed and novel tumour entities have been discovered. The aim of this review is to discuss recent molecular findings and open questions in diagnosing chromophobe-like/oncocytic neoplasms. The broader differential diagnosis of chromophobe-like and oncocytoma-like neoplasms includes SDH-deficient renal cell carcinoma, fumarate hydratase (FH) deficient RCC, epitheloid angiomyolipoma ('oncocytoma like'), MiT family translocation RCC and the emerging entity of eosinophilic solid and cystic renal cell carcinoma. After separation of these tumours from chromophobe RCC, it becomes evident that chromophobe RCC are low malignant tumours with a 5-6% risk of metastasis. Recent next generation sequencing (NGS) and DNA methylation profiling studies have confirmed Thoenes' theory of a distal tubule derived origin of chromophobe RCC and renal oncocytomas. Comprehensive genomic analyses of chromophobe RCC have demonstrated a low somatic mutation rate and identified TP53 and PTEN as the most frequently mutated genes, whereas 'unclassified' RCC with oncocytic or chromophobe-like features can show somatic inactivating mutations of TSC2 or activating mutations of MTOR as the primary molecular alterations. For the future, it would be desirable to create a category of 'oncocytic/chromophobe RCC, NOS' with the potential of further molecular studies for identification of TSC1/2 mutations in these rare tumours.

Patients with sarcomatoid renal cell carcinoma - re-defining the first-line of treatment: A meta-analysis of randomised clinical trials with immune checkpoint inhibitors

BACKGROUND

Sarcomatoid renal cell carcinoma (sRCC) represents a rare form of renal cell carcinoma marked by an aggressive biology, poor prognosis and little benefit from anti-angiogenic targeted therapy. More promising results come from the recent therapeutic strategy based on immune checkpoint inhibitor (ICI) combinations.

MATERIALS AND METHODS

For this meta-analysis, we searched MEDLINE/PubMed, the Cochrane Library and American Society of Medical Oncology (ASCO) Meeting abstracts for phase II or III randomised clinical trials. Data extraction was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. The hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS) with the relative 95% confidence intervals were extracted from studies. Summary HRs were calculated using random- or fixed-effects models, depending on the heterogeneity of the included studies.

RESULTS

Four studies were selected for final analysis, including 467 patients (226 treated in with ICI combinations and 241 received sunitinib in the control arms). ICI-based combinations were associated with an improved PFS and OS compared with sunitinib, with a reduction of more than 40% of progression (HR = 0.56; p < 0.0001) and mortality (HR = 0.56; p = 0.001) risk. Moreover, ICI-based combinations are associated with a objective response rate (ORR) of more than 50% (versus 20% with sunitinib), corresponding to a doubled risk of achieving an ORR compared with controls (relative risk [RR] = 2.15; p < 0.00001). Finally, immunotherapy significantly increased the possibility to obtain complete responses (RR = 8.15, p = 0.0002) with an incidence of 11%.

CONCLUSION

Our data support the efficacy of ICI-based combinations for sRCC therapy, redefining the first-line treatment.