Metastatic Sarcomatoid Renal Cell Carcinoma Research Articles

Establishment and validation of a nomogram to select patients with metastatic sarcomatoid renal cell carcinoma suitable for cytoreductive radical nephrectomy

IntroductionMetastatic renal cell carcinoma (mRCC) with sarcomatoid features has a poor prognosis. Cytoreductive radical nephrectomy (CRN) can improve prognosis, but patient selection is unclear. This study aimed to develop a prediction model for selecting patients suitable for CRN.Materials and methodsPatients with a diagnosis of mRCC with sarcomatoid features in the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015 were retrospectively reviewed. CRN benefit was defined as a survival time longer than the median overall survival (OS) in patients who did not receive CRN. A prediction nomogram was established and validated using the SEER cohort (training and internal validation) and an external validation cohort.ResultsOf 900 patients with sarcomatoid mRCC, 608 (67.6%) underwent CRN. OS was longer in the CRN group than in the non-CRN group (8 vs. 6 months, hazard ratio (HR) = 0.767, p = 0.0085). In the matched CRN group, 124 (57.7%) patients survived >6 months after the surgery and were considered to benefit from CRN. Age, T-stage, systematic therapy, metastatic site, and lymph nodes were identified as independent factors influencing OS after CRN, which were included in the prediction nomogram. The monogram performed well on the training set (area under the receiver operating characteristic (AUC) curve = 0.766, 95% confidence interval (CI): 0.687–0.845), internal validation set (AUC = 0.796, 95% CI: 0.684–0.908), and external validation set (AUC = 0.911, 95% CI: 0.831–0.991).ConclusionsA nomogram was constructed and validated with good accuracy for selecting patients with sarcomatoid mRCC suitable for CRN.

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

BackgroundRenal 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. ObjectiveHere, we report the outcomes with ICT for patients with mRCC and S/R dedifferentiation by CN status. Design, setting, and participantsA 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. InterventionCN performed at any time point; nephrectomy with curative intent was excluded. Outcome measurements and statistical analysisICT 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 limitationsA 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. ConclusionsIn 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 summaryImmunotherapy 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 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.

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.

678P Cytoreductive nephrectomy (CN) for patients with metastatic sarcomatoid and/or rhabdoid (S/R) renal cell carcinoma (RCC) treated with immune checkpoint inhibitors (ICI)

Recent clinical data has renewed the debate regarding the role of CN for patients with metastatic RCC (mRCC). Metastatic S/R clear cell RCC is an aggressive variant that responds to ICI. However, the role of CN for metastatic S/R RCC in the ICI era has not been reported to date. Here, we evaluate CN outcomes in patients with metastatic S/R RCC treated with ICI.

Cabozantinib in Pretreated Patients with Metastatic Renal Cell Carcinoma with Sarcomatoid Differentiation: A Real-World Study

Renal cell carcinoma with sarcomatoid differentiation is a highly aggressive form of kidney cancer. We aimed to analyze the outcomes of patients treated with cabozantinib for metastatic renal cell carcinoma with sarcomatoid features. We retrospectively collected data from 16 worldwide centers. Overall survival and progression-free survival were analyzed using Kaplan-Meier curves. Cox proportional models were used for univariate and multivariate analyses. We collected data from 66 patients with metastatic sarcomatoid renal cell carcinoma receiving cabozantinib as second-line (51%) or third-line (49%) therapy. The median progression-free survival from the start of cabozantinib was 7.59 months (95% confidence interval [CI] 5.75-17.49) and was longer in male patients (8.81 vs 5.95 months, p = 0.042) and in patients without bone metastases (7.59 vs 5.11 months, p = 0.010); the median overall survival was 9.11 months (95% CI 7.13-23.80). At the multivariate analysis, female sex (hazard ratio = 1.81; 95% CI 1.02-3.37,p = 0.046), bone metastases (hazard ratio = 2.62; 95% CI 1.34-5.10, p = 0.005), and International Metastatic Renal Cell Carcinoma Database Consortium criteria (hazard ratio = 3.04; 95% CI 1.54-5.99, p = 0.001) were significant predictors of worse overall survival. Our data show that cabozantinib is active in pretreated patients with sarcomatoid renal cell carcinoma. Biomarkers are needed in this field to select patients for multi-kinase inhibitors or other options.

Abstract IA25: Adult deletion of Lats1/2 leads to sarcomatoid renal cell carcinoma

Abstract Alterations of the Hippo signaling pathway have been found in patients with sarcomatoid renal cell carcinoma, a highly aggressive kidney disease with rapid progression and poor prognosis. It is unclear whether deregulated Hippo pathway is a primary cause of sarcomatoid cancers. To investigate whether conditional (kidney-specific) Hippo knockout leads to renal cancer development and/or sarcomatoid dedifferentiation, we conditionally inactivated both Lats1 and Lats2 from the adult renal proximal tubule epithelial cells. Mosaic deletion of Lats1 and Lats2 in the adult proximal tubules results in cell-autonomous sarcomatoid renal cell carcinoma ((54%) as early as 8 weeks after gene deletion) and lung metastasis. RNA sequencing of tumors compared to control renal cortices revealed massive transcriptional changes, with 2,292 genes significantly upregulated (FC&amp;gt;2) and 2261 genes significantly downregulated (FCË‚0.5). To visualize the cellular onset and progression of renal defects, we conducted histologic examination at different time points after induction of Lats1/2 deletion. Mutant kidneys displayed tubular atrophy with glomerular cysts. Loss of proximal tubule epithelial markers, and de novo expression of the mesenchymal marker vimentin, indicated that kidney epithelial cells had undergone an epithelial-to-mesenchymal transition (EMT). These studies demonstrate that loss of Lats1/2 rapidly leads to aggressive, metastatic sarcomatoid renal cell carcinoma. Citation Format: Antoine Reginensi, Sanjay Jain, Benjamin Humphreys, Jess Shen, Didier Hodzic, Jeff Wrana, Helen McNeill. Adult deletion of Lats1/2 leads to sarcomatoid renal cell carcinoma [abstract]. In: Proceedings of the AACR Special Conference on the Hippo Pathway: Signaling, Cancer, and Beyond; 2019 May 8-11; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(8_Suppl):Abstract nr IA25.

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

BackgroundThis 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/MethodsDemographic 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.ResultsOf 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.ConclusionsData 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.

Immunotherapy in metastatic sarcomatoid renal cell carcinoma: A single institution experience

IntroductionImmune checkpoint inhibitors (CPIs) were recently approved in advanced clear cell renal cell carcinoma (RCC) and could be a promising option for metastatic RCC with sarcomatoid differentiation (sRCC) which otherwise carry a poor prognosis. We sought to compare outcomes between patients who received immunotherapy (IO) including CPIs or high dose interleukin-2 (HD IL2) for metastatic sRCC versus those who did not. Patients and MethodsWe performed a single-center retrospective data analysis of 44 consecutive sRCC patients with any percentage of sarcomatoid differentiation from our institutional RCC database of whom 34 received IO and 10 patients did not. ResultsBaseline variables between the two groups were not significantly different except for a greater percentage of patients with ≥40% sarcomatoid differentiation in the non-IO cohort. At a median follow-up of 27.6 months, patients treated with IO had a median overall survival of 57.6 months compared to 6.6 months in patients not treated with IO (p = 0.0002). Overall response rates (ORR) between the IO and non-IO group were 35.3% and 0% respectively (p = 0.06). When IO was given in the 1st line setting, the ORR was 25.0%, as compared to 44.4% in the 2nd line setting and beyond though limitations of small sample sizes apply. Immune-related adverse events (IRAE) occurred in 38.2% of patients in the IO group, with grade 3 events (mostly gastrointestinal) in 20.6% with no grade 4 or 5 events. IRAEs led to interruption or discontinuation of immunotherapy in 26.5%. ConclusionOur results support IO as an effective therapeutic option for patients with metastatic sarcomatoid RCC. Further study of various IO regimens, including those affecting the interleukin-2 signaling pathway, and their efficacy in neoadjuvant and adjuvant settings are warranted in sRCC.

A prospective phase II trial of gemcitabine plus axitinib in patients with sarcomatoid type renal carcinoma.

616 Background: Sarcomatoid renal cell carcinoma (SRCC) is a rare but very aggressive type of RCC. The treatment option for SRCC is very limited, and there have been anecdotal reports of very good responders to gemcitabine or vascular endothelial growth factor receptor tyrosine kinaase inhibitors (VEGFR TKI). We conducted multicenter phase 2 trial of gemcitabine plus axitinib (GX) in patients (pts) with recurrent or metastatic SRCC to evaluate its efficacy and safety. Methods: Eligibility criteria included histologically confirmed metastatic or recurrent RCC with sarcomatoid component of 25% or more on resected kidney or exclusive sarcomatoid carcinoma on needle biopsy, ECOG PS 0-2, measurable lesion by RECIST v1.1, and adequate cardiac, hepatic, renal and bone marrow function. Pts with uncontrolled hypertension, prior exposure to gemcitabine or VEGFR TKI were exclude. Pts received gemcitabine 1,000 mg/m2 intravenously on days 1 and 8 by 3-week cycle and axitinib 5 mg twice daily. The primary endpoint was objective response rate (ORR) according to RECIST v1.1, and secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity. Results: Twenty-five pts were enrolled between Oct 2014 and Aug 2018. Median age was 61 (range 33-80), and 84% was male. ECOG PS were 1 (92%) and 2 (8%), and 52% had prior nephrectomy. Clear cell carcinoma was the most common histology of carcinoma component, and median percentage of sarcomatoid component was 90% (25-100%). Pts belonged to intermediate (28%) and poor (72%) risk group according to IMDC risk stratification. Median 6 cycles of GX were administered, and 56%, 28%, and 12% of pts achieved PR, SD, and PD, respectively, with an ORR of 56% and median duration of response of 2.5 months. With a median follow-up duration of 21.4 mo, median PFS was 4.9 mo (95% CI, 3.5-13.3), and median OS was 8.4 months (95% CI 3.5-13.3 months). Most adverse events were manageable, and no unexpected toxicities were found. One pt died of grade 5 pneumonia. Conclusions: GX showed promising efficacy in pts with SRCC. GX might be considered as one of treatment options for pts with SRCC, although efficacy of GX should be confirmed in larger trial.

Treatments, Outcomes, and Validity of Prognostic Scores in Patients With Sarcomatoid Renal Cell Carcinoma: A 20-Year Single-Institution Experience.

Metastatic renal cell carcinoma (RCC) with a sarcomatoid component is a rare disease associated with a poor prognosis. We report the outcomes of 47 patients with metastatic sarcomatoid RCC (SRCC) treated with different modalities including chemotherapy, tyrosine kinase inhibitors, or immunotherapy over 2 decades in a French cancer center. Furthermore, we assessed the validity of prognostic scores in this subset of RCC. Patients were retrospectively identified from the database of the pathology department of the University Hospital of Strasbourg. We enrolled all patients with RCC with a sarcomatoid component diagnosed between 1995 and 2016. Patients with nonmetastatic RCC were excluded. Recorded variables included: clinical stage, metastatic sites, pathologic stage, type of treatments, prognostic group, and survival data. The primary end point was overall survival. The institutional ethical committee approved the study protocol. Of 104 patients with SRCC, 47 patients with metastatic SRCC were included. The median age was 60 years (range, 41-77 years). Median length of follow-up was 34 months (range, 1-180 months). Fifty-five percent of patients had known metastases at diagnosis. Lung represented the first metastatic site (70%) followed by glandular (28%), bone (23%), liver (21%), and brain (6%). Fifteen percent of patients received immunotherapy including cytokine-based therapy (n= 7), or checkpoint inhibitors (n= 2). Moreover, 7 patients received chemotherapy. Five patients received no systemic treatment because of their poor performance status. Of 42 treated patients, 2 patients achieved complete response and 9 partial response (24%). Median overall survival was 13.3 months. International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) and Memorial Sloan Kettering Cancer Center (MSKCC) prognostic groups were valid in this subset of SRCC patients. A sarcomatoid percentage cutoff of 30% had the strongest influence on overall survival. Despite the arrival of tyrosine kinase inhibitors 10 years ago, metastatic SRCC remains a disease of poor prognosis and difficult to treat. Chemotherapy regimen and targeted therapies showed little activity in SRCC. IMDC score is a relevant prognostic factor in SRCC patients. Additionally, the MSKCC score, the sarcomatoid percentage, the necrotic fraction, and the vascular invasion could prove useful in identifying patients with a more favorable prognosis. These findings could help toward better patient stratification in clinical trials. Prospective trials assessing new drugs including immune checkpoint inhibitors are currently ongoing to improve SRCC survival.

Long-term survival following multidisciplinary treatment of metastatic sarcomatoid renal cell carcinoma: a case report

IntroductionWe report the case of a 62-year-old woman diagnosed with sarcomatoid renal cell carcinoma.Case presentationA 62-year-old Asian woman presented with macroscopic hematuria. A histological and immunohistochemical study of a tumor biopsy specimen led to a suspected diagnosis of sarcomatoid renal cell carcinoma. She underwent surgical tumor resection that included her left kidney. A histological and immunohistochemical study of the resected tumor confirmed the diagnosis of sarcomatoid renal cell carcinoma. The pathological stage was pT3bpN2, and multiple lung metastases were detected (pT3bpN2cM1; stage IV). Our patient was classified as “poor risk” according to the Memorial Sloan Kettering Cancer Center risk criteria. Interferon-α was administered as adjuvant therapy, and her lung metastases remained stable. However, a computed tomography scan and bone scintigraphy 2 years later revealed multiple bone metastases. External beam radiotherapy was performed for the bone metastases. Despite continuing interferon-α during radiotherapy, multiple skull and liver metastases appeared. Oral administration of the tyrosine kinase inhibitor axitinib was initiated as a second-line therapy, and our patient achieved a stable state for 11 months. As the liver metastases progressed and meningeal dissemination newly appeared, oral administration of the mammalian target of rapamycin inhibitor everolimus was initiated as a third-line therapy. Our patient remains alive 71 months after diagnosis and has maintained a comparatively good quality of life.ConclusionA literature review revealed that metastatic sarcomatoid renal cell carcinoma has very poor prognosis, with a survival of <1 year despite systemic therapy. Our patient in this present case achieved long-term survival, a rare incidence worthy of report.

PANDA: pathway and annotation explorer for visualizing and interpreting gene-centric data.

Objective. Bringing together genomics, transcriptomics, proteomics, and other -omics technologies is an important step towards developing highly personalized medicine. However, instrumentation has advances far beyond expectations and now we are able to generate data faster than it can be interpreted.Materials and Methods. We have developed PANDA (Pathway AND Annotation) Explorer, a visualization tool that integrates gene-level annotation in the context of biological pathways to help interpret complex data from disparate sources. PANDA is a web-based application that displays data in the context of well-studied pathways like KEGG, BioCarta, and PharmGKB. PANDA represents data/annotations as icons in the graph while maintaining the other data elements (i.e., other columns for the table of annotations). Custom pathways from underrepresented diseases can be imported when existing data sources are inadequate. PANDA also allows sharing annotations among collaborators.Results. In our first use case, we show how easy it is to view supplemental data from a manuscript in the context of a user’s own data. Another use-case is provided describing how PANDA was leveraged to design a treatment strategy from the somatic variants found in the tumor of a patient with metastatic sarcomatoid renal cell carcinoma.Conclusion. PANDA facilitates the interpretation of gene-centric annotations by visually integrating this information with context of biological pathways. The application can be downloaded or used directly from our website: http://bioinformaticstools.mayo.edu/research/panda-viewer/.

Survival Outcomes and Tumor IMP3 Expression in Patients with Sarcomatoid Metastatic Renal Cell Carcinoma.

Metastatic renal cell carcinoma with sarcomatoid histology (SmRCC) is associated with poor survival. No data is available from randomized trials on the efficacy of vascular endothelial growth factor (VEGF) and mammalian target of rapamycin (mTOR) inhibitors in SmRCC. We identified SmRCC patients from a single institutional database. To identify predictive and prognostic biomarkers, immunohistochemistry (IHC) analysis was performed on the tumor samples for downstream targets of VEGF and mTOR pathways. Survival outcomes were stratified by IHC analysis, extent of sarcomatoid component, Memorial Sloan-Kettering Cancer Center (MSKCC), and Heng risk criteria. Twenty-seven patients with SmRCC were included. First line therapy included targeted therapy (n = 19), immunotherapy (n = 4), cytotoxic chemotherapy (n = 1), and no treatment (n = 3). Median OS was 8.2 months (95% CI 3.8–14.2 months). Median survival in months, based on MSKCC and Heng risk groups, was favorable 89.3 versus 84.5, intermediate 9.5 versus 12.7, and poor 3.9 versus 5.1. None of the IHC markers predicted outcomes of treatment with VEGF or mTOR inhibitors. Only tumor IMP3 expression was associated with inferior OS, although not statistically significant (IMP3 negative 14.2 versus IMP3 positive 4.9 months; HR 0.46, 95% CI 0.16–1.21; P = 0.12). The study was limited by small sample size.

P3-33-2 - A Case of Metastatic Sarcomatoid Renal Cell Carcinoma Which Obtained Long-Term Survival by Multidisciplinary Treatment

We report a case of sarcomatoid renal cell carcinoma which occurred in a 62-year-old woman. Presentation symptom was macroscopic hematuria. Diagnosis was performed by the histological and immunohistochemical study of a tumor biopsy specimen that showed suspicious of sarcomatoid renal cell carcinoma. The patient underwent surgical resection of the tumor including the left kidney and the spleen. Histological and immunohistochemical study of the tumor showed sarcomatoid renal cell carcinoma. The pathological stage was diagnosed to be pT3bN2, and multiple lung metastases were detected. Interferon-alpha was administrated as adjuvant therapy, and the lung metastases were stable. However, multiple bone metastases appeared. External beam radiotherapy for bone metastases was performed. Interferon-alpha was continued during radiotherapy, nevertheless, multiple brain and liver metastases appeared. Oral administration of tyrosine kinase inhibitor axitinib was started as second-line therapy, and the patient was able to be kept in stable state for eleven months. Since the liver metastases were progressed eventually, oral administration of mammalian target of rapamycin inhibitor everolimus was started as third-line therapy. The patient results in 51 months survival after diagnosis and a comparatively good quality of life within that time. A review of the literature reveals metastatic sarcomatoid renal cell carcinoma being very poor prognosis less than 1-year survival in spite of systemic therapy. The patient in our present case surviving in long-term, which is rarely reported in the literature, is worth to be reported.

Comparison VEGF-pathway elements and EMT markers in patients with sarcomatoid metastatic renal cell carcinoma and risk-matched controls.

e15613 Background: The presence of sarc elements in pts with RCC portends a poor prognosis. Some studies have focused on epithelial-to-mesenchymal transition (EMT) as a driver of sarc ccRCC; howeve...

Treatment obstacles for metastatic clear cell renal cell carcinoma of Fuhrman grade IV and with sarcomatoid histologies.

e15604 Background: Sarcomatoid metastatic renal cell carcinoma and RCC Fuhrman grade IV represents an aggressive subset of disease, but a definitive therapeutic strategy in this cases still remain questionable. We seek to define outcomes associated with its therapy with special attention to diagnostic ambiguities and their impact on therapeutic decisions. Methods: The analyzed cohort consisted of patients with ccRCC diagnosed/treated at MIM from Jan 2007 to Jan 2014. Baseline clinical features, detailed radiologic and histologic reports were collected. Patients with mRCC either with sarcomatoid features and/or with Fuhrman grade IV disease were followed. Outcome was assessed by a dedicated radiologist for determination of tumor response, PFS and OS. Survival was estimated with the Kaplan-Meier method, and associations with survival outcome were analyzed with univariable and multivariable Cox regression analyses. All patients treated with sunitinib and pazopanib underwent radical nephrectomy. Results: Amon...

Successful mammalian target of rapamycin inhibitor maintenance therapy following induction chemotherapy with gemcitabine and doxorubicin for metastatic sarcomatoid renal cell carcinoma.

This study presents a case of metastatic sarcomatoid renal cell carcinoma (RCC) treated with systemic chemotherapy followed by mammalian target of rapamycin inhibitor maintenance therapy. A 63-year-old male presented with lumbago, and lumbar vertebral tumors were detected by magnetic resonance imaging. Subsequent computed tomography (CT) revealed a right renal tumor and CT-guided biopsy of the right renal and left sacroiliac tumors determined pure sarcomatoid carcinoma without a clear cell component. Two cycles of combination chemotherapy comprising of gemcitabine (1,500 mg/m2 on day one) and doxorubicin (50 mg/m2 on day one) resulted in a 20% reduction in the longest diameter of the right renal tumor. However, due to grade 3 neutropenia, the chemotherapy was discontinued and temsirolimus (25 mg once weekly), which binds to the cytoplasmic protein, FKBP-12, and inhibits mTOR, was administered. Stable disease was maintained for 19 months with temsirolimus and no major adverse events, with the exception of grade 2 nausea, were observed. The patient succumbed to their disease at 30 months following the initiation of treatment. These results suggested that systemic chemotherapy followed by temsirolimus maintenance is a feasible treatment option for patients with metastatic sarcomatoid RCC.

Clinical outcomes and survival of patients (pts) with sarcomatoid metastatic renal cell carcinoma (smRCC).

535 Background: SmRCC is a rare variant of RCC associated with poor outcome. No definitive therapeutic recommendations exist. We present survival outcomes in pts with smRCC treated with systemic therapy. Methods: From a single institutional database (years 2000-2012), we identified 21 pts with documented sarcomatoid features who received systemic therapy. Survival was assessed in the overall cohort and in subgroups divided by clinicopathologic characteristics, including the extent of sarcomatoid features, and Memorial Sloan-Kettering Cancer Center (MSKCC) risk criteria. Sarcomatoid component of the tumor was classified by predominant (≥20%) and non-predominant (&lt;20%). Immunohistochemistry (IHC) analysis was performed for mammalian target of rapamycin (mTOR) signaling, phosphorylated ribosomal protein S6, proviral integration site proteins (PIM 1,2,3), Beta-catenin, E-cadherin, phosphatase and tensin homolog (PTEN), U3 small nucleolar ribonucleoprotein (IMP-3), p53, and epithelial membrane antigen (EMA) on tumor samples, where available. Results: 21 pts were included with a median age of 62 years (range 39-74) and 13 pts were male (62%). One pt received first line cytotoxic chemotherapy, 3 pts received first line immunotherapy, and 17 pts received targeted therapy. Pts belonged to the following MSKCC risk categories: 1 (5%) favorable, 13 (62%) intermediate and 7 (33%) poor risk. Median overall survival (OS) of the entire cohort was 249 days (95% CI 161-519 days). Median OS in pts stratified as MSKCC poor, intermediate, and good risk was 2556, 430, and 137 days respectively (Poor vs Intermediate HR 4.38, p = 0.0159, CI 1.30-19.90). There was no significant difference in OS in pts with sarcomatoid predominant disease vs. non-predominant disease (234 vs 286 days, p = 0.744, HR 0.85, CI 0.31-2.39). Conclusions: Overall OS in pts with smRCC is inferior compared to that reported in clear cell variant mRCC. Although MSKCC risk scores may be useful in determining prognosis, further studies are needed to identify relevant biomarkers and define the optimal therapeutic strategy for this disease. Correlation of survival outcomes with the IHC profile of tumors will be presented.

Outcome of metastatic sarcomatoid renal cell carcinoma (sRCC): Results from the International mRCC Database Consortium.

4565 Background: Sarcomatoid differentiation in metastatic RCC (sRCC) is associated with poor prognosis. Robust data regarding outcome in the targeted therapy era is lacking. Methods: Clinical features, prognostic factors, and treatment outcomes in mRCC patients with and without sarcomatoid histology treated with targeted therapy were retrospectively analyzed and compared. Results: 2,286 patients were identified (non-sRCC(n=2,056); sRCC(n=230)). sRCC patients had significantly worse Heng prognostic group distribution compared to non-sRCC (11% vs 19% favorable risk, 49% vs 57% intermediate risk, and 40% vs 24% poor risk; p&lt;0.0001). Time from original diagnosis to relapse (excluding synchronous metastatic disease) in the sRCC patients was 18.8 months compared to 42.9 months in non-sRCC group; p&lt;0.0001. There was no significant difference in the incidence of CNS metastases (6-8%) or underlying clear cell histology (87-88%). Greater than 93% of patients received VEGF inhibitors as first line therapy; 21% achieved an objective response in the sRCC group as compared to 26% in the non-sRCC group with significantly more sRCC patients (43% vs. 21%) having primary refractory disease (p&lt;0.0001, for both). sRCC patients had significantly less use of second-line (p=0.018) and third-line (p=0.0004) systemic therapy. The median PFS / OS was 4.5 months / 10.4 months in sRCC patients and 7.8 months / 22.5 months in non-sRCC patients (p&lt;0.0001 for both). Sarcomatoid histology was associated with a significantly worse PFS and OS after adjusting for the individual Heng risk factors in multivariable analysis (HR 1.5, p&lt;0.0001 for both). Conclusions: Patients with sRCC have worse baseline prognostic criteria, a shorter time to relapse and worse clinical outcome to targeted therapy compared to patients with non-sRCC. Additional insight into the biology of sRCC is needed to develop alternative therapeutics.