Sarcomatoid differentiation in renal cell carcinoma: a study of 101 cases.

Histopathology of Surgically Treated Renal Cell Carcinoma: Survival Differences by Subtype and Stage

Fuhrman Grade Provides Higher Prognostic Accuracy Than Nucleolar Grade for Papillary Renal Cell Carcinoma

Renal cell carcinoma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up†.

Sarcomatoid renal cell carcinoma is a relatively rare tumor and accounts for about 5% of allrenal cell carcinomas. The results of multivariate prognostic modeling show that the presence of sarcomatoid differentiation in renal cell carcinoma is an unfavorable predictor of the clinical course and underlying diseases. Objective - а comparative analysis of the expression of a number of proteins in carcinomatous and sarcomatoid components in various histological variants of sarcomatoid renal cell carcinoma and an assessment of their diagnostic significance. Surgical specimens from 49 patients diagnosed with renal neoplasms were investigated. Paraffin sections were immunohistochemically examined using the standard protocol. Based on the morphological analysis and IHC studies, out of 49 neoplasms in 24 (49%) cases revealed morphoimmunohistochemical signs of clear cell renal cell carcinoma, in 9 (18%) neoplasms chromophobe renal cell carcinoma, in 8 (16%) samples -papillary renal cell carcinoma, in 1 (2%) collecting duct carcinoma and in 2 (4%) cases, unclassified renal cell carcinoma. In 4 (8%) samples tumor cells did not express specific markers of renal cell carcinoma and in additional immunophenotyping 2 (4%) cases of leiomyosarcoma and solitary fibrous tumor were diagnosed, respectively, and in 1 (2%) case – monophasic synovial sarcoma. There is a relationship between the number of sarcomatoid cells and the tumor stage in sarcomatoid renal cell carcinomas. It was found that the number of sarcomatoid cells in the stages of pT3-pT4 (n=28; 64%), in the majority of cases (n=27; 96%), was more than 50% of the entire tumor population.

214 IDENTIFICATION OF CHARACTERISTIC GENE EXPRESSION IN SARCOMATOID RENAL CELL CARCINOMA

Cytogenetic and molecular genetic techniques have been used in demonstrating the chromosomal abnormalities which characterize specific subtypes of renal cell carcinoma (RCC). The aim of this study was to determine the efficiency of fluorescent in situ hybridization (FISH) technique in characterizing various subtypes of RCC based on the presence of specific chromosome abnormalities found in each RCC subtype. FISH was performed on touch imprint smears from eight renal cell carcinomas histologically confirmed by established criteria. In four tumors with histologic features of chromophobe renal cell carcinoma (ChRCC), interphase FISH was performed using centromeric probes for chromosomes 1, 2, 6, 10, 12, 17 and 21. All four ChRCC tumors showed one FISH signal corresponding to one copy number for each of these chromosomes. Two papillary RCCs included in this study showed trisomy 7 and 17, and loss of chromosome Y, using the corresponding chromosome centromeric probes. Similarly, we tested two clear cell RCCs for chromosome 3 short arm deletion with DNA probe 3p21.3. Both tumors showed loss of 3p21.3 signal. We conclude that interphase FISH performed on touch imprint smears is a relatively simple, rapid and reliable method for detecting chromosome abnormalities which are specific for various subtypes of RCC.

Focus on kidney cancer

To evaluate the cytologic features of each subtype of renal cell carcinoma (RCC) for separating the various subtypes. Thirty-eight renal fine needle aspiration (FNA) specimens with surgical resection follow-up were retrospectively reviewed and classified without knowledge of the resection specimen diagnosis. These included 18 clear cell RCCs, 8 papillary RCCs, 4 oncocytomas, 2 chromophobe RCCs, 2 sarcomatoid RCCs and 4 metastases to the kidney. Seventy-four percent of the primary renal lesions were correctly classified. All 4 oncocytomas and the 2 chromophobe tumors were correctly classified, while both sarcomatoid RCCs and 3 of 8 papillary RCCs were misclassified as clear cell RCC. One clear cell RCC was misclassified as papillary type. Two clear cell and one papillary RCC were nondiagnostic; in each case the tumor had a prominent cystic component. All four metastases were correctly identified. Subclassification of RCC by FNA is relatively accurate. In this study, the most common error was to misclassify papillary and sarcomatoid RCC as clear cell RCC.

Renal cell carcinoma (RCC) is a renal cortical tumor with high clinical incidence. The effect of glutathione peroxidases (GPXs) on RCC and the possible mechanism are still unclear. This study aims to explore the expression level of GPXs gene in RCC and its effect on the clinical prognosis of patients with RCC via bioinformatics analysis. The mRNA expressions of GPXs family genes were obtained from the public data of The Cancer Genome Atlas (TCGA) database. The Kruskal-Wails test was used to analyze the differences in mRNA expression of GPXs family genes between samples from patients with RCC and the normal population. UALAN databases were used to analyze the differences in protein expression of GPXs family genes between samples from patients with renal clear cell carcinoma and the normal population, and to evaluate the role of GPXs family genes in RCC. The Kaplan-Meier Plotter was used to analyze the correlation between different types of RCC and overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and progression-free survival (PFS). Kaplan-Meier survival curve was drawn based on the GPX8 gene expression to study the relationship between GPX8 gene expression and prognosis of RCC patients. Based on the results of multivariate Cox regression analysis, a Nomogram scoring model for RCC prediction was established by introducing GPX8 gene. The mRNA expressions of GPX1 and GPX4 were higher in the sample of renal chromophobe cell carcinoma, renal clear cell carcinoma, and renal papillary cell carcinoma than those in the normal population (all P<0.01), and GPX7 and GPX8 were significantly over-expressed in patients with renal papillary cell carcinoma and renal clear cell carcinoma (all P<0.01). Compared with the normal group, the protein expressions of GPX1, GPX2, GPX7, and GPX8 were increased significantly in renal clear cell carcinoma (all P<0.01), while GPX3 and GPX4 expressions were decreased significantly (both P<0.01). The protein expressions of GPX1, GPX2, GPX7, and GPX8 were increased significantly in patients with renal clear cell carcinoma at different tumor grades (all P<0.01), while GPX3 and GPX4 expressions were decreased significantly (both P<0.01). Survival analysis showed that OS, DFS, DSS, and PFS were all decreased in patients with clear cell carcinoma compared with patients with papillary cell carcinoma and chromophobe cell carcinoma. According to the GPX8 level, patients were assigned into the low, medium, and high expression groups. Compared with the low GPX8 level group, the OS (P<0.01), DFS (P=0.03), DSS (P<0.01), and PFS (P=3.18×10-7) were significantly decreased in the high level group. Univariate Cox proportional regression analysis showed that the high level of GPX8 was associated with poor OS of 3 different types of renal cancer. Multifactorial analysis showed that GPX8 was an independent factor affecting the OS of patients with renal papillary cell carcinoma. Race and post tumor node metastasis (pTNM) typing were independent factors influencing the OS of patients with renal clear cell carcinoma. GPX8 and pTMN were independent factors influencing the OS of patients with renal chromophobe cell carcinoma. Based on these variables, the Nomogram risk models of 3 types of cell carcinoma were established, and the discrimination and calibration of the models were evaluated using the Consistency index (C-index) and calibration curves. The C-index of the risk model of renal papillary cell carcinoma was 0.62 (95% CI 0.51 to 1.00, P=0.03). The results of receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) was 0.88. The C-index of the risk model of renal clear cell carcinoma was 0.72 (95% CI 0.52 to 1.00, P=0.03). The results of ROC curve showed that the AUC was 0.90. The C-index of the risk model of chromophobe cell carcinoma of kidney was 0.90 (95% CI 0.85 to 1.00, P<0.01). The results of ROC curve showed that the AUC was 0.59. GPXs family genes, especially GPX8, are potential markers for poor prognosis of RCC, and the occurrence and development of RCC can be predicted in clinical practice based on the expressions of GPXs family genes.

384 Background: Renal cell carcinoma (RCC) comprises a heterogeneous group of tumors of different histological subtypes. Each subtype is characterized by distinct immunohistochemical and molecular features and different biology. Currently, patients with advanced RCC have poor disease outcomes despite recent breakthroughs in immunotherapy. Chimeric antigen receptor (CAR)-T cell therapy has produced remarkably effective and durable clinical responses in hematological malignancies. However, there have been very limited success of CAR-T cell therapy in solid tumors. CD70 and its signaling partner CD27 are cell surface molecules that have emerged as novel targets for immune modulation approach. CD70 is also a promising target for CAR-T cell therapy, as it is overexpressed on multiple types of solid tumors including RCC and not expressed in most normal tissue. Studies have shown clear cell RCC (CCRCC) commonly expresses CD70. To date, no studies has evaluated CD70 expression in metastatic RCC in comparison with primary RCC. Methods: Four Tissue Microarrays (TMAs) were constructed using 395 tumors from 374 patients with RCC, 4 to 8 cores per tumor. There were 359 primary tumors, 36 metastatic tumors, and 344 matched normal. The primary RCC included 309 CCRCC including 11 with sarcomatoid differentiation, 38 papillary RCC (pRCC) including 1 with sarcomatoid differentiation, 8 chromophobe RCC (ChRCC), and 4 collecting duct RCC (CDC). The metastatic RCC were composed of 31 CCRCC including 3 with sarcomatoid differentiation and 5 PRCC. CD70 expression was evaluated using immunohistochemistry (IHC) and Definiens image analysis. CD70 expression was measured using the percentage of CD70-positive tumor cells. A CD70-positive tumor was defined as CD70 immunopercentage ≥ cutoff value in at least one core. Results: CD70 staining was detected in tumor cells in primary and metastatic RCC, with minimal staining in normal renal parenchyma. When the positive cutoff was defined as ≥1% of tumor cells demonstrating CD70 staining, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 98%, 32%, 0%, 11%, and 46%, respectively. When the positive cutoff was defined as ≥ 25% of tumor cells stained positive for CD70, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 41%, 10%, 0%, 0%, and 23%, respectively. Finally, when the positive cutoff was defined as ≥50%, the positive rate in CCRCC, pRCC, ChRCC, CDC, and SarRCC was 22%, 2%, 0%, 0%, and 8%, respectively. Metastatic RCC showed a higher % of tumor cells expressing CD70 compared to primary RCC for patients with CCRCC (mean 15% vs 9%) or SarRCC (12% vs 9%). Conclusions: Clear cell and sarcomatoid RCC are the RCC subtypes that demonstrate the highest CD70 expression. CD70 expression is further increased in metastatic lesions compared to the primary tumors. Anti-CD70 CAR-T cell therapy may benefit a significant fraction of patients with advanced CCRCC and sarcomatoid RCC.

Our objective was to compare cancer-specific survival and to examine associations with outcome among the histologic subtypes of renal cell carcinoma (RCC). We studied 2385 patients whose first surgery between 1970 and 2000 was a radical nephrectomy for sporadic, unilateral RCC. All RCC tumors were classified following the 1997 Union Internationale Contre le Cancer and American Joint Committee on Cancer guidelines. There were 1985 (83.2%) patients with clear cell, 270 (11.3%) with papillary, 102 (4.3%) with chromophobe, 6 (0.3%) with collecting duct, 5 (0.3%) with purely sarcomatoid RCC and no underlying histologic subtype, and 17 (0.7%) with RCC, not otherwise specified. Cancer-specific survival rates at 5 years for patients with clear cell, papillary, and chromophobe RCC were 68.9%, 87.4%, and 86.7%, respectively. Patients with clear cell RCC had a poorer prognosis compared with patients with papillary and chromophobe RCC (p <0.001). This difference in outcome was observed even after stratifying by 1997 tumor stage and nuclear grade. There was no significant difference in cancer-specific survival between patients with papillary and chromophobe RCC (p = 0.918). The 1997 TNM stage, tumor size, presence of a sarcomatoid component, and nuclear grade were significantly associated with death from clear cell, papillary, and chromophobe RCC. Histologic tumor necrosis was significantly associated with death from clear cell and chromophobe RCC, but not with death from papillary RCC. Our results demonstrate that there are significant differences in outcome and associations with outcome for the different histologic subtypes of RCC, highlighting the need for accurate subtyping.

Expression of vitamin D 3 receptor in kidney tumors

A sarcomatoid component can occur in all histologic subtypes of renal cell carcinoma (RCC) and indicates an aggressive tumor. We studied 2381 patients treated with radical nephrectomy for RCC between 1970 and 2000. A urologic pathologist reviewed the microscopic slides from all tumor specimens for the presence of a sarcomatoid component, defined as a RCC with any malignant spindle cell component. All tumors with a sarcomatoid component were classified as nuclear grade 4. A total of 120 (5.0%) patients had RCC with a sarcomatoid component, including 94 who died of RCC at a mean of 1.4 years following nephrectomy (median 8 months; range 44 days to 10 years). Cancer-specific survival rates at 2 and 5 years following nephrectomy were 33.3% and 14.5%, respectively. The presence of distant metastases at the radical nephrectomy and histologic tumor necrosis were significantly associated with death from RCC among patients with sarcomatoid RCC. Patients with clear cell (conventional) RCC and chromophobe RCC were more likely to have tumors with a sarcomatoid component (5.2% and 8.7%, respectively) compared with patients with papillary RCC (1.9%). The presence of a sarcomatoid component was significantly associated with death from RCC for all three subtypes (P < 0.001). Even among patients with grade 4 clear cell RCC, the presence of a sarcomatoid component was significantly associated with outcome, both univariately (risk ratio 1.59; P = 0.010) and after adjusting for TNM stage, tumor size, and histologic tumor necrosis (risk ratio 1.46; P = 0.037).

Background and Objectives: Metastasis is a major cause of death in renal cell carcinoma (RCC) patients; therefore, a better understanding of the metastatic process and the ability to predict metastasis in advance is important for treating patients with RCC. This study aimed to investigate whether histological subtypes of RCC and other factors, such as nuclear grade and sarcomatoid differentiation, could predict the probability and location of metastases in patients with RCC. Materials and Methods: Cases of clear-cell, papillary, chromophobe, and sarcomatoid RCC were retrieved and analyzed from the Surveillance, Epidemiology, and End Results databases. Results: When comparing the metastatic patterns among the three histologic subtypes, patients with clear-cell RCC were significantly more likely to have brain and lung metastases. Moreover, patients with papillary RCC were significantly less likely to develop bone metastases and more likely to develop lymph node metastases. Patients with chromophobe RCC are significantly more likely to develop liver metastases. As the nuclear grade increased, there was also a significantly increased tendency for clear-cell RCC to metastasize to the lungs. Patients with sarcomatoid RCC had a higher rate of metastasis, with a significantly higher probability of metastasis to the bone and lungs, than those with all three histological subtypes did. Conclusions: Histological subtype, nuclear grade, and sarcomatoid differentiation were significant predictors of metastasis in patients with RCC.

BackgroundRenal collecting duct carcinoma (CDC) is a rare and lethal subtype of renal cell carcinoma (RCC). The genomic profile of the Chinese population with CDC remains unclear. In addition, clinical treatments are contradictory. In this study, we aimed to identify the genomic mutation spectrum of CDC in the Chinese population.MethodsWhole-exome sequencing was performed using the Illumina Novaseq™ 6000 platform. MuTect2 detects single-nucleotide variants (SNVs) and small scale insertions/deletions (INDELs). The identified mutations were annotated with ANNOVAR and validated by Sanger sequencing. Control-FREEC was used to detect copy number variation (CNV), and GISTIC was applied to detect frequently mutated altered regions. These data were compared with associated The Cancer Genome Atlas cohorts.ResultsTen normal-matched CDC patients were included. The mean tumour mutation burden was 1.37 Mut/Mb. Six new recurrent somatic mutated genes were identified, including RBM14, MTUS1, GAK, DST, RNF213 and XIRP2 (20% and 2 of 10, respectively), and validated by Sanger sequencing. In terms of common mutated genes, SETD2 was altered in both CDC and other RCC subtypes but not in bladder urothelial carcinoma (BLCA); CDKN2A was a driver gene in both CDC (SNV: 10%, 1 of 10) and BLCA but not in other RCC subtypes. Next, 29 amplifications and 6 deletions of recurrent focal somatic CNVs were identified by GISTIC2.0, which displayed differences from kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP) and BLCA cohorts. Of note, CDKN2A (CNV alteration: 30%, 3 of 10) and CDKN2A-AS1 were the only overlapping genes of these four cohorts. Importantly, the CDKN2A mutation in our cohort differed from previous studies in urinary carcinomas. Moreover, CDKN2A-altered cases had significantly worse overall survival than wild-type cases in both KIRC and KIRP cohorts. In addition, the most frequently altered genomic pathway of our CDC cohort was the CDKN2A-mediated p53/RB1 pathway.ConclusionsOur study offers the first genomic spectrum of the Chinese population with CDC, which differs from that of the Western population. The altered CDKN2A-mediated p53/RB1 pathway might provide new insight into potential therapeutic targets for CDC patients.