Renal cell carcinoma with rhabdoid features

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 vein thrombosis in a patient secondary to high-grade rhabdoid renal cell carcinoma: a case report and review of literature

Introduction

Renal cell carcinoma, a common kidney tumour which is often incidentally discovered on imaging, can manifest with atypical symptoms. Renal cell carcinoma with rhabdoid features is a rare occurrence and even rarer in case of adults. Renal cell carcinoma has the tendency to form thrombus that can migrate to renal vein, inferior vena cava and even right atrium.

Case presentation

The authors report a case of an 81-year-old male with rhabdoid renal cell carcinoma presenting with persistent cough for 6-7 months. with tumour thrombus extending into the renal vein and hepatic inferior vena cava. The patient was found feeble for the surgery and hence was treated on anticancer drugs pembrolizumab and axitinib.

Conclusion

Renal cell carcinoma has the tendency to form tumour thrombus in renal vein and inferior vena cava. Prognosis without surgical intervention in these conditions is very poor.

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.

Prognostic factors in renal cell carcinoma: A single‑center study

Renal cell carcinoma (RCC) is a heterogeneous and complex disease with numerous pathophysiologic variants. ~40% of patients succumb due to the progression of the disease, making RCC the most fatal of the common urologic malignancies. Prognostic factors are indicators of the progression of the disease, and the precise determination of these factors is important for evaluating and managing RCC. In the present study, it was aimed to determine and find associations among the histopathological features of RCCs and their impact on survival and metastasis. This is a cross-sectional study of RCC cases who have undergone partial or radical nephrectomy from March 2008 to October 2021 and have been pathologically reviewed at Shorsh General Teaching Hospital in Sulaimani, Iraq. The data in the pathology studies were supplemented by follow-up of the patients to obtain information about survival, recurrence and metastasis. In total, 228 cases of RCC were identified, among whom 60.5% were men and 39.5% were women, with a median age of 51 years. The main tumor types were clear cell RCC (71.1%), papillary RCC (13.6%), and chromophobe RCC (11%). Various measures of aggressiveness, including tumor necrosis, sarcomatoid change, microvascular invasion, and parameters of invasiveness (invasion of the renal sinus and other structures), were significantly correlated with each other, and they were also associated with reduced overall survival and an increased risk of metastasis on univariate analysis. However, on multivariate analysis, only tumor size and grade, and microvascular invasion retained statistical significance and were associated with a lower survival rate. In conclusion, pathological parameters have an impact on prognosis in RCC. The most consistent prognostic factors can be tumor size and grade, and microvascular invasion.

SWI/SNF Complex Alterations in Tumors with Rhabdoid Features: Novel Therapeutic Approaches and Opportunities for Adoptive Cell Therapy

The SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin-remodeling complex is one of the most remarkably altered epigenetic regulators in cancer. Pathogenic mutations in genes encoding SWI/SNF-related proteins have been recently described in many solid tumors, including rare and aggressive malignancies with rhabdoid features with no standard therapies in advanced or metastatic settings. In recent years, clinical trials with targeted drugs aimed at restoring its function have shown discouraging results. However, preclinical data have found an association between these epigenetic alterations and response to immune therapy. Thus, the rationale for immunotherapy strategies in SWI/SNF complex alteration-related tumors is strong. Here, we review the SWI/SNF complex and how its dysfunction drives the oncogenesis of rhabdoid tumors and the proposed strategies to revert this alteration and promising novel therapeutic approaches, including immune checkpoint inhibition and adoptive cell therapy.

Comparison of tyrosine kinase inhibitors in the treatment of metastatic renal cell carcinoma with rhabdoid and sarcomatoid differentiations

OBJECTIVE

To investigate the efficacy of tyrosine kinase inhibitors (TKIs) in the treatment of metastatic renal cell carcinoma (mRCC) with rhabdoid (mRCC-R) and sarcomatoid (mRCC-S) differentiations.

MATERIALS AND METHODS

In this single-institutional cohort study, we included patients with RCC with rhabdoid (RCC-R) and sarcomatoid (RCC-S) differentiation, who were treated with TKIs after metastasis at our institute from 2013 to 2021. Patient characteristics, treatments, and clinical outcomes were recorded and analyzed.

RESULTS

We identified 111 patients with RCC-R or RCC-S differentiations, of which 23 patients were included in the final analysis. Of the 23 patients, 10 (43.5%) were grouped as mRCC-R and 13 (56.5%) as mRCC-S. At a median follow-up of 40 months, mRCC-R and mRCC-S progressed in 7 of 10 and 12 of 13 patients, respectively. In addition, four and eight patients died in the mRCC-R and mRCC-S groups, respectively. The median progression-free survival (PFS) of the two groups was 19 months (mRCC-R: 95% confidence interval [CI] 4.08-33.92) and 7 months (mRCC-S: 95% CI 2.03-11.96), while the median overall survival (OS) was 32 months and 21 months, respectively. mRCC-S had a worse prognosis than mRCC-R. Based on the univariate Cox regression model, single metastasis or multiple metastasis of tumor, rhabdoid differentiation, and sarcomatoid differentiation were predictors of PFS but not OS.

CONCLUSION

The efficacy of TKIs in the treatment of mRCC-R and mRCC-S may be different.

Prognostic impact of CD73/adenosine 2A receptor (A2AR) in renal cell carcinoma and immune microenvironmental status with sarcomatoid changes and rhabdoid features

One of the most aggressive forms of kidney cancer is renal cell carcinoma (RCC) with sarcomatoid changes and rhabdoid features (S/R). Adenosine produced via CD73 binds to adenosine 2 A receptor (A2AR) and suppress antitumor immunity. Here, we attempted to analyze the expression of CD73/A2AR in S/R RCC and examined its relationships with other immune microenvironments and prognostic effect. Sixty cases of S/R RCC were selected. CD73/A2AR expression levels were graded in the tumor cells or infiltrating immune cells on a score of 0-3 and divided into low (0 or 1) or high (2 or 3) groups. PD-L1 results were defined by the tumor proportion score (TPS). We counted the numbers of CD8⁺, FOXP3⁺, CD68⁺, and CD163⁺ immune cells. The rates of CD73/A2AR expression in epithelial component (23.3% and 15.0%) were lower than those in high-grade component (70.0% and 45.0%). CD73/A2AR were significantly correlated to high numbers of regulatory Tcells and macrophages of M2 subtype (CD73: P = 0.0059 and 0.0002; A2AR: P = 0.0002 and 0.018, respectively). Multivariate analysis showed that CD73/A2AR expressions were independent markers of unfavorable prognosis in S/R RCCs (P = 0.0204 and 0.0116, respectively). In RCC, the S/R component had higher expressions of CD73/A2AR than the epithelial component, and CD73/A2AR were independent prognostic factors. Compared with other RCCs, S/R RCCs are more effective at blocking adenosine signaling and CD73/A2AR inhibitors are expected to enhance the therapeutic efficacy and improve the prognosis of immune checkpoint inhibitor therapies.

Navigating the Current Landscape of Non-Clear Cell Renal Cell Carcinoma: A Review of the Literature

Non-clear cell renal cell carcinoma (nccRCC) is an entity comprised of a heterogeneous constellation of RCC subtypes. Genomic profiling has broadened our understanding of molecular pathogenic mechanisms unique to individual nccRCC subtypes. To date, clinical trials evaluating the use of immunotherapies and targeted therapies have predominantly been conducted in patients with clear cell histology. A comprehensive review of the literature has been undertaken in order to describe molecular pathogenic mechanisms pertaining to each nccRCC subtype, and concisely summarise findings from therapeutic trials conducted in the nccRCC space.

Hot topics in renal cancer pathology: implications for clinical management

INTRODUCTION

The updated European Association of Urology (EAU) Guidelines issued a weak recommendation for adjuvant pembrolizumab for patients with high-risk operable clear cell Renal Cell Carcinoma (ccRCC). High risk of recurrence was defined, as per protocol-criteria, as T2 with nuclear grade 4 or sarcomatoid differentiation, T3 or higher, regional lymph node metastasis, or stage M1 with no evidence of disease. Considering the heterogeneous population included in the recommendation, it has been questioned if adjuvant pembrolizumab may lead to overtreatment of some patients as well as undertreatment of patients with worse prognosis.

AREAS COVERED

In this review, we discuss the issues related to the assessment of pathological features required to identify those patients harboring a high-risk tumor, highlighting the issue related to interobserver variability and discuss the currently available prognostic scoring systems in ccRCC.

EXPERT OPINION

PPathologist assessment of prognostic features suffers from interobserver variability which may depend on gross sampling and the pathologist's expertise. The presence of clear cell feature is not sufficient criteria by itself to define ccRCC since clear cell can be also found in other histotypes. Application of molecular biomarkers may be useful tools in the near future to help clinicians identify patients harboring tumors with worse prognosis.

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.

The significance of SMARCB1 in the pathogenesis of renal cell carcinoma with rhabdoid features

BACKGROUND

Renal cell carcinoma with rhabdoid features (RCC-RF) is an aggressive histologic variant in the adults and is usually unresponsive to standard chemotherapy.

METHODS

Expression of SMARCB1/INI1 was examined in primary RCC-RF (n = 5). Stable INI1 with/without prostaglandin E2 receptor 1 (EP1) knockdown cell lines were created in the ACHN and 786-O RCC cell lines and measured for epidermal growth factor receptor (EGFR)-related signaling pathways. Chemosensitivity to targeted drugs in vitro was tested after knocking down of INI1 in both cell lines. The outcome of co-targeting of INI1 and EP1 in RCC was examined using a tumorigenicity assay.

RESULTS

Expression of INI1 was markedly reduced at both transcriptional and translational levels in primary RCC-RF. Immunohistochemical expression of INI1 protein was lost in the nuclei of rhabdoid cells compared with conventional RCC (n = 8). Using two cell lines with different genetic background, we showed that knocking down of INI1 activates the EGFR signaling with up-regulated AKT and ERK pathways and sensitizes cancer cells to Erlotinib treatment in vitro. However, cell-line dependent effects were also demonstrated with reference to impact of INI1 or EP1 on cell growth, migration and response to Gefitinib or Everolimus treatment in vitro.

CONCLUSION

Inactivation of INI1 may play a role in the pathogenesis of RCC-RF. Erlotinib is recommended in the management of patients with INI1-related RCC.

Adverse Histopathologic Characteristics in Small Papillary Renal Cell Carcinomas Have Minimal Impact on Prognosis

OBJECTIVES

Tumor size has long been used in the management decision-making of patients with renal masses. Active surveillance had recently gained traction in selected patients with tumor size of 4 cm or less. Adverse histopathologic characteristics in papillary renal cell carcinoma (PRCC) have been shown to correlate with worse prognosis. We aimed to study whether such features in small PRCCs provide additional prognostic information.

METHODS

Nephrectomies from our institution were collected and reviewed to evaluate for adverse histopathologic features. Clinical follow-up information was collected for all cases. Relationships between the variables were examined by Wilcoxon test and logistic regression.

RESULTS

We identified 291 consecutive cases of PRCC. Adverse tumor histopathologic characteristics were significantly related to size. In PRCCs with size greater than 4 cm, there were more cases with high World Health Organization/International Society of Urological Pathology grade and necrosis. Adverse histologic features are less commonly seen in small PRCC and are not associated with lower disease-free survival or disease-specific survival.

CONCLUSIONS

Identification of these features in small PRCCs (≤4 cm) through needle core biopsy examination would not provide additional prognostic information in patients for whom active surveillance is considered. Clinical and radiologic follow-up in patients with small renal masses that have a known histologic diagnosis of PRCC should be sufficient.

New developments in existing WHO entities and evolving molecular concepts: The Genitourinary Pathology Society (GUPS) update on renal neoplasia

The Genitourinary Pathology Society (GUPS) reviewed recent advances in renal neoplasia, particularly post-2016 World Health Organization (WHO) classification, to provide an update on existing entities, including diagnostic criteria, molecular correlates, and updated nomenclature. Key prognostic features for clear cell renal cell carcinoma (RCC) remain WHO/ISUP grade, AJCC/pTNM stage, coagulative necrosis, and rhabdoid and sarcomatoid differentiation. Accrual of subclonal genetic alterations in clear cell RCC including SETD2, PBRM1, BAP1, loss of chromosome 14q and 9p are associated with variable prognosis, patterns of metastasis, and vulnerability to therapies. Recent National Comprehensive Cancer Network (NCCN) guidelines increasingly adopt immunotherapeutic agents in advanced RCC, including RCC with rhabdoid and sarcomatoid changes. Papillary RCC subtyping is no longer recommended, as WHO/ISUP grade and tumor architecture better predict outcome. New papillary RCC variants/patterns include biphasic, solid, Warthin-like, and papillary renal neoplasm with reverse polarity. For tumors with 'borderline' features between oncocytoma and chromophobe RCC, a term "oncocytic renal neoplasm of low malignant potential, not further classified" is proposed. Clear cell papillary RCC may warrant reclassification as a tumor of low malignant potential. Tubulocystic RCC should only be diagnosed when morphologically pure. MiTF family translocation RCCs exhibit varied morphologic patterns and fusion partners. TFEB-amplified RCC occurs in older patients and is associated with more aggressive behavior. Acquired cystic disease (ACD) RCC-like cysts are likely precursors of ACD-RCC. The diagnosis of renal medullary carcinoma requires a negative SMARCB1 (INI-1) expression and sickle cell trait/disease. Mucinous tubular and spindle cell carcinoma (MTSCC) can be distinguished from papillary RCC with overlapping morphology by losses of chromosomes 1, 4, 6, 8, 9, 13, 14, 15, and 22. MTSCC with adverse histologic features shows frequent CDKN2A/2B (9p) deletions. BRAF mutations unify the metanephric family of tumors. The term "fumarate hydratase deficient RCC" ("FH-deficient RCC") is preferred over "hereditary leiomyomatosis and RCC syndrome-associated RCC". A low threshold for FH, 2SC, and SDHB immunohistochemistry is recommended in difficult to classify RCCs, particularly those with eosinophilic morphology, occurring in younger patients. Current evidence does not support existence of a unique tumor subtype occurring after chemotherapy/radiation in early childhood.

Acute kidney injury promotes development of papillary renal cell adenoma and carcinoma from renal progenitor cells

Acute tissue injury causes DNA damage and repair processes involving increased cell mitosis and polyploidization, leading to cell function alterations that may potentially drive cancer development. Here, we show that acute kidney injury (AKI) increased the risk for papillary renal cell carcinoma (pRCC) development and tumor relapse in humans as confirmed by data collected from several single-center and multicentric studies. Lineage tracing of tubular epithelial cells (TECs) after AKI induction and long-term follow-up in mice showed time-dependent onset of clonal papillary tumors in an adenoma-carcinoma sequence. Among AKI-related pathways, NOTCH1 overexpression in human pRCC associated with worse outcome and was specific for type 2 pRCC. Mice overexpressing NOTCH1 in TECs developed papillary adenomas and type 2 pRCCs, and AKI accelerated this process. Lineage tracing in mice identified single renal progenitors as the cell of origin of papillary tumors. Single-cell RNA sequencing showed that human renal progenitor transcriptome showed similarities to PT1, the putative cell of origin of human pRCC. Furthermore, NOTCH1 overexpression in cultured human renal progenitor cells induced tumor-like 3D growth. Thus, AKI can drive tumorigenesis from local tissue progenitor cells. In particular, we find that AKI promotes the development of pRCC from single progenitors through a classical adenoma-carcinoma sequence.

Metastatic renal cell carcinoma to pancreas and gastrointestinal tract: a clinicopathological study of 3 cases and review of literature

BACKGROUND

Renal Cell Carcinoma (RCC) metastasizes in approximately 20-30% cases. The most common sites for metastases are the lungs, bones, liver, and brain. Metastases of RCC in the gastrointestinal tract (GIT) are very rare. Metastatic RCC has a poor prognosis. We herein present a case series of three patients with metastatic disease in the colon, duodenum, and pancreas following complete resection of RCC.

METHODS

Hematoxylin and Eosin and immunohistochemical slides of 3 cases of RCC metastatic to GIT were reviewed. These cases were diagnosed between 2002 and 2019 at French Medical Institute for Mothers and Children (FMIC), Kabul, Afghanistan, and Aga Khan University Hospital (AKUH), Karachi, Pakistan. We also present a detailed review of published literature.

RESULTS

We reviewed cases of three patients, two females and one male, with a mean age of 57.3 years (range 40-67 years) who underwent nephrectomy for RCC. They developed metastases in the colon, pancreas, and duodenum, respectively 12-168 months (median time 156 months) following primary tumor resection. The patient with metastatic RCC in colon presented with abdominal pain and constipation. An ulcerated mass was found on colonoscopy 30 cm from the anal verge. Diagnosis of RCC with rhabdoid features was confirmed in both primary and metastatic tumors. The second patient developed a metastatic nodule in the head of pancreatic while the third patient developed metastatic nodules in the duodenum and pancreas which were detected by Computed Tomography (CT) scanning. Histopathological examination confirmed the presence of clear cell RCC in the metastatic nodules in both cases.

CONCLUSION

Metastatic RCC should be considered in the differential diagnosis of mass in the gastrointestinal (including pancreaticobiliary) tract especially in presence of a past history of RCC. These patients should be screened thoroughly by physical examination and appropriate imaging studies.

SWI/SNF-deficient neoplasms of the genitourinary tract

Since the discovery of association of SMARCB1 mutations with malignant rhabdoid tumors and renal medullary carcinoma, mutations in genes of the SWI/SNF chromatin remodeling complex have been increasingly identified across a diverse spectrum of neoplasms. As a group, SWI/SNF complex subunit mutations are now recognized to be the second most frequent type of mutations across tumors. SMARCB1 mutations were originally reported in malignant rhabdoid tumors of the kidney and thought to be pathognomonic for this tumor. However, more broadly, recognition of typical rhabdoid cytomorphology and SMARCB1 mutations beyond rhabdoid tumors has changed our understanding of the pathobiology of these tumors. While mutations of SWI/SNF complex are diagnostic of rhabdoid tumors and renal medullary carcinoma, their clinical relevance extends to potential prognostic and predictive utility in other tumors as well. Beyond SMARCB1, the PBRM1 and ARID1A genes are the most frequently altered members of the SWI/SNF complex in genitourinary neoplasms, especially in clear cell renal cell carcinoma and urothelial carcinoma. In this review, we provide an overview of alterations in the SWI/SNF complex encountered in genitourinary neoplasms and discuss their increasing clinical importance.

Malignant rhabdoid tumor of the kidney in an adult with loss of INI1 expression and mutation in the SMARCB1 gene

A 57-year-old man with left flank pain was referred to our institute. Computed tomography scans revealed two enhancing masses in the left kidney. The clinical diagnosis was renal cell carcinoma (RCC). He underwent a radical nephrectomy with an adrenalectomy. Two well-circumscribed solid masses in the hilum and the lower pole (4.5 × 3.5 cm and 7.0 × 4.1 cm) were present. Poorly cohesive uniform round to polygonal epithelioid cells making solid sheets accounted for most of the tumor area. The initial diagnosis was RCC, undifferentiated with rhabdoid features. As the tumor showed loss of INI1 expression and a mutation in the SMARCB1 gene on chromosome 22, the revised diagnosis was a malignant rhabdoid tumor (MRT) of the kidney. To date, only a few cases of renal MRT in adults have been reported. To the best of our knowledge, this is the first report of MRT in the native kidney of an adult demonstrating a SMARCB1 gene mutation, a hallmark of MRT.

Metastatic renal cell carcinoma involving colon with unusual histologic features and diagnostic challenges: A case report

•

Metastatic RCC in the colon, although very rare, should be kept in the differential diagnosis of patients with lower GI bleeding, particularly patients with a prior history of kidney mass or nephrectomy

•

Most common type of primary or metastatic RCC is Clear-cell-type.

•

We reported the first case of rhabdoid-RCC metastasizing to colon.

•

In the absence of IHC-stains, rhabdoid-RCC may be misdiagnosed as soft-tissue-sarcoma or other poorly differentiated carcinomas.

•

Our case exclusively occurred in a woman while colonic metastasis of RCC commonly occurring in males.

Introduction and importance

Renal cell carcinoma (RCC) accounts for 3% of all malignancies in adults, on its own being the 3rd most common urologic malignancy. Commonly RCC metastasizes to lung, bone, liver, brain but rarely to colorectum. Here we present the metastasis of RCC to colon with unusual histologic features.

Case presentation

A 40-year-old woman presented with abdominal pain and constipation. Colonoscopy showed an ulcerative mass 30 cm from anal verge. Subsequently, she underwent abdominoperineal resection of the involved portion of colon and the biopsy was sent to us for histopathological analysis. Grossly, it was a large fungating mass. Microscopic examination revealed a malignant neoplasm with polygonal cells, abundant eosinophilic cytoplasm, eccentric nuclei and prominent nucleoli. Immunohistochemistry confirmed the diagnosis of RCC.

Clinical discussion

Colon rarely infiltrated by metastasis from RCC and so far, around 25 of such cases have been reported in the literature. Most common metastatic type of RCC to gastrointestinal tract is clear cell type. In our patient, the type of the metastatic RCC to colon was RCC with rhabdoid features. RCC with rhabdoid features is rare (3–5% of all RCC), but it is highly aggressive with higher chance of metastasis, extra renal invasion and poorer prognosis.

Conclusion

RCC should be considered as one of the differential diagnosis of colorectal cancers. Appropriate immunohistochemical workup would then reveal the correct diagnosis.

Integrative molecular characterization of sarcomatoid and rhabdoid renal cell carcinoma

Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings build on prior work and shed light on the molecular drivers of aggressivity and responsiveness to ICI of S/R RCC.

Sarcomatoid and rhabdoid tumours are highly aggressive forms of renal cell carcinoma that are also responsive to immunotherapy. In this study, the authors perform a comprehensive molecular characterization of these tumours discovering an enrichment of specific alterations and an inflamed phenotype.

Malignant rhabdoid tumor arising in a mixed epithelial, stromal tumor of kidney: report of a male case, review of the literature

Mixed epithelial and stromal tumor (MEST) of the kidney is a rare biphasic tumor composed of both stromal and epithelial components, the latter showing a variable proportion of solid to cystic areas. These tumors show a marked female predominance, commonly occur in perimenopausal age groups, and often have an ovarian-type stroma with ER and PR positivity, suggesting steroids may play a role in pathogenesis. Although typically benign, rare cases showing malignant transformation have been reported. We present a case of a 42-year-old man with a 10 cm right kidney mass located in the renal pelvis. Histologically, the majority of the tumor was composed of a diffuse, sheet-like growth of malignant cells demonstrating a rhabdoid morphology with large nuclei, prominent nucleoli, and eosinophilic eccentric cytoplasm. Brisk mitotic activity and coagulative type necrosis was also noted. Intimately associated with this malignant rhabdoid component was a much smaller portion of tumor featuring variably sized bland epithelial tubules embedded within a stroma composed of bland spindle cells and areas of hyalinization, diagnostic of MEST. By immunohistochemistry, the malignant rhabdoid tumor portion of the neoplasm showed complete loss of nuclear INI-1, while the MEST component retained nuclear expression of this antigen. With these features taken together, our case represents a malignant rhabdoid tumor arising in a background of MEST. To our knowledge, this case represents the first case of a MEST showing malignant transformation in the form of malignant rhabdoid tumor in a male patient in the English language literature.

Updates in Histologic Grading of Urologic Neoplasms

CONTEXT.—

Tumor histology offers a composite view of the genetic, epigenetic, proteomic, and microenvironmental determinants of tumor biology. As a marker of tumor histology, histologic grading has persisted as a highly relevant factor in risk stratification and management of urologic neoplasms (ie, renal cell carcinoma, prostatic adenocarcinoma, and urothelial carcinoma). Ongoing research and consensus meetings have attempted to improve the accuracy, consistency, and biologic relevance of histologic grading, as well as provide guidance for many challenging scenarios.

OBJECTIVE.—

To review the most recent updates to the grading system of urologic neoplasms, including those in the 2016 4th edition of the World Health Organization (WHO) Bluebook, with emphasis on issues encountered in routine practice.

DATA SOURCES.—

Peer-reviewed publications and the 4th edition of the WHO Bluebook on the pathology and genetics of the urinary system and male genital organs.

CONCLUSIONS.—

This article summarizes the recently updated grading schemes for renal cell carcinoma, prostate adenocarcinomas, and bladder neoplasms of the genitourinary tract.

The SWI/SNF chromatin-remodeling complex status in renal cell carcinomas with sarcomatoid or rhabdoid features

The presence of sarcomatoid or rhabdoid features (which are associated with advanced disease and poor prognosis) is rarely observed in the subtypes of renal cell carcinoma (RCC). The SWI/SNF chromatin-remodeling complex, which is composed of evolutionarily conserved core subunits including SMARCB1/INI1 (SMARCB1), SMARCA4/BRG1 (SMARCA4), SMARCC1/BAF155 (SMARCC1), and SMARCC2/BAF170 (SMARCC2), can be regarded as the prototype of an epigenetic regulator of gene expression that is involved in tumor suppression. We analyzed the histological, immunohistochemical, and clinicopathological status in 72 cases of RCC with sarcomatoid or rhabdoid features, focusing on the expression status of the subunits of SWI/SNF chromatin-remodeling complex proteins. Cases with lost or reduced expression were defined as showing aberrant expression. The frequency of aberrant SMARCA4 immunoexpression of a sarcomatoid or rhabdoid component in clear cell RCC (ccRCC) (47/50, 94%) was significantly higher than that in non-ccRCC (4/9, 44%) (p < 0.001). In ccRCC without sarcomatoid or rhabdoid features, aberrant SMARCA4 immunoexpression was observed in 33 of 48 (67%) cases. Immunoreactivities for SMARCB1, SMARCA2, and SMARCC2 were retained in almost all subtypes of RCC. The patients with aberrant SMARCA4 expression in RCC with sarcomatoid or rhabdoid features achieved shorter progression-free survival compared with the patients with retained SMARCA4 expression (all subtypes of RCC, p = 0.0212; ccRCC, p = 0.0265). These results suggest that in ccRCC, aberrant SMARCA4 expression is one of the adverse prognostic factors or a high-grade malignant transforming factor. The evaluation of SMARCA4 immunoexpression may be a useful diagnostic tool to help distinguish ccRCC from non-ccRCC.

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.

Dataset for the reporting of renal biopsy for tumour: recommendations from the International Collaboration on Cancer Reporting (ICCR)

The International Collaboration on Cancer Reporting (ICCR) has developed a suite of detailed datasets for international implementation. These datasets are based on the reporting protocols developed by the Royal College of Pathologists (UK), The Royal College of Pathologists of Australasia and the College of American Pathologists, with modifications undertaken by international expert groups appointed according to ICCR protocols. The dataset for the reporting of renal biopsy for tumour is designed to provide a structured reporting template containing minimum data recording key elements suitable for international use. In formulating the dataset, the ICCR panel incorporated recommendations from the 2012 Vancouver Consensus Conference of the International Society of Urological Pathology (ISUP) and the 2016 edition of the WHO Bluebook on tumours of the urinary and male genital systems. Reporting elements were divided into Required (Core) and Recommended (Non-core) components of the report. Required elements are as follows: specimen laterality, histological tumour type, WHO/ISUP histological tumour grade, sarcomatoid morphology, rhabdoid morphology, necrosis, lymphovascular invasion and coexisting pathology in non-neoplastic kidney. Recommended reporting elements are as follows: operative procedure, tumour site(s), histological tumour subtype and details of ancillary studies. In particular, it is noted that fluorescence in situ hybridisation studies may assist in diagnosing translocation renal cell carcinoma (RCC) and in distinguishing oncocytoma and eosinophilic chromophobe RCC. It is anticipated that the implementation of this dataset into routine clinical practice will facilitate uniformity of pathology reporting worldwide. This, in turn, should have a positive impact on patient treatment and the quality of demographic information held by cancer registries.

Impact of rhabdoid differentiation on postoperative outcome for patients with N0M0 renal cell carcinoma

BACKGROUND AND OBJECTIVE

We assessed the aggressiveness of localized renal cell carcinoma (N0M0 RCC) with rhabdoid differentiation (RD) after partial or radical nephrectomy.

METHODS

A total of 604 patients with N0M0 RCC who had undergone partial or radical nephrectomy at a single institution were included in this study. Clinicopathological and outcome data on recurrence-free survival (RFS), cancer-specific survival (CSS), and time to recurrence (TTR) were analyzed using Kaplan-Meier methods, log-rank test, univariate and multivariable Cox proportional hazard models, and concordance index. We also evaluated the RFS and CSS in a propensity score-matched cohort to reduce inherent differences. Among the 604 patients, RD was identified in RCC specimens from 24 patients.

RESULTS

At the median postoperative follow-up period of 53 months, 58 patients (12 with RD) showed recurrence and 26 patients (7 with RD) had died from RCC. Multivariate analyses showed that RD was an independent risk factor of RFS (hazard ratio 2.81; P = 0.0266) and CSS (hazard ratio 5.18; P = 0.00182). By RD adding to standard risk factors, the concordance indices for RFS and CSS increased 0.77 to 0.79, and 0.76 to 0.79, respectively. Subgroup analysis showed that the presence of RD in RCC specimens was more important for predicting poor RFS and CSS in the early pathological tumor category (≤pT2) subgroup compared to in the advanced tumor category (≥pT3) subgroup. Patients with RD showed a significantly shorter TTR than patients with RCC without RD (7.5 vs. 18 months: P = 0.0150). The propensity score-matched cohort included 24 patients with RD and 24 without RD, of which patients RD showed significantly shorter RFS than those without RD (P = 0.0026).

CONCLUSIONS

In summary, the aggressiveness of N0M0 RCC with RD increased the risk of postoperative recurrence, particularly in the early pathological stage. The short TTR also demonstrated the aggressiveness of RCC with RD.

Data set for the reporting of carcinoma of renal tubular origin: recommendations from the International Collaboration on Cancer Reporting (ICCR)

AIMS

The International Collaboration on Cancer Reporting (ICCR) has provided detailed data sets based upon the published reporting protocols of the Royal College of Pathologists, the Royal College of Pathologists of Australasia and the College of American Pathologists.

METHODS AND RESULTS

The data set for carcinomas of renal tubular origin treated by nephrectomy was developed to provide a minimum structured reporting template suitable for international use, and incorporated recommendations from the 2012 Vancouver Consensus Conference of the International Society of Urological Pathology (ISUP) and the fourth edition of the World Health Organisation Bluebook on tumours of the urinary and male genital systems published in 2016. Reporting elements were divided into those, which are required and recommended components of the report. Required elements are: specimen laterality, operative procedure, attached structures, tumour focality, tumour dimension, tumour type, WHO/ISUP grade, sarcomatoid/rhabdoid morphology, tumour necrosis, extent of invasion, lymph node status, surgical margin status, AJCC TNM staging and co-existing pathology. Recommended reporting elements are: pre-operative treatment, details of tissue removed for experimental purposes prior to submission, site of tumour(s) block identification key, extent of sarcomatoid and/or rhabdoid component, extent of necrosis, presence of tumour in renal vein wall, lymphovascular invasion and lymph node status (size of largest focus and extranodal extension).

CONCLUSIONS

It is anticipated that the implementation of this data set in routine clinical practice will inform patient treatment as well as provide standardised information relating to outcome prediction. The harmonisation of data reporting should also facilitate international research collaborations.

Evaluation of microvascular invasion as a prognostic factor in the progression of non-metastatic renal cancer

Introduction

The aim of this study was to describe the prognostic impact of microvascular invasion (MVI) in patients with non-metastatic renal cell cancer.

Material and methods

We carried out a retrospective, descriptive and analytical study of patients with non-metastatic renal cell carcinoma who had undergone a radical or partial nephrectomy. Patients were divided according to the presence of MVI. In each group, clinical and pathological characteristics were evaluated. Metastasis-free and cancer-specific survival was evaluated by the Kaplan Meier method. The multivariate analysis was performed with Cox proportional method in order to predict risk factors of metastasis and cancer-specific mortality.

Results

A total of 221 patients with a median of 40-month long follow-up were evaluated. Patients with MVI+ were 40 (18%) while those with MVI – were 181 (82%). In the univariate analysis, the presence of MVI had a strong correlation with symptomatic tumors (OR 3.56; p 0.0003), tumor size (OR 12.08; p <0.0001), nuclear grade (OR 6.99; p <0.0001), pathological stage (OR 35.8; p <0.0001), distance metastasis (OR 4.16; p 0.0001), and death by cancer (OR 4.7; p 0.0004). However, in the multivariate analysis it is not presented as an independent predictor of metastasis (HR 0.45; p 0.11) or cancer-specific mortality (HR 0.93; p 0.91).

Conclusions

In our series, MVI is associated with unfavorable tumors characteristics. In spite of this, it does not seem to be an independent predictor for metastasis and death by non-metastatic renal cancer.

WHO/ISUP classification, grading and pathological staging of renal cell carcinoma: standards and controversies

PURPOSE

Pathological parameters assessed on biopsies and resection specimens have a pivotal role in the diagnosis, prognosis and management of patients with renal cell carcinoma (RCC).

METHODS

A non-systematic literature search was performed, updated to January 2018, to identify key standards and controversies in the pathological classification, grading and staging of RCC.

RESULTS

Although most RCCs exhibit characteristic morphology that enables easy categorisation, RCCs show considerable morphological heterogeneity and it is not uncommon for there to be difficulty in assigning a tumour type, especially with rarer tumour subtypes. The differentiation between benign and malignant oncocytic tumours remains a particular challenge. The development of additional immunohistochemical and molecular tests is needed to facilitate tumour typing, because of the prognostic and therapeutic implications, and to enable more reliable identification of poorly differentiated metastatic tumours as being of renal origin. Any new tests need to be applicable to small biopsy samples, to overcome the heterogeneity of renal tumours. There is also a need to facilitate identification of tumour types that have genetic implications, to allow referral and management at specialist centres. Digital pathology has a potential role in such referral practice.

CONCLUSION

Much has been done to standardise pathological assessment of renal cell carcinomas in recent years, but there still remain areas of difficulty in classification and grading of these heterogeneous tumours.

High grade infiltrative adenocarcinomas of renal cell origin: New insights into classification, morphology, and molecular pathogenesis

Collecting duct carcinoma was described over 30 years ago as a renal tumor, based in the medullary collecting system, with tubulopapillary morphology, prominent infiltrative growth, and stromal desmoplasia. While diagnostic workup has always emphasized exclusion of upper tract urothelial carcinoma and metastatic adenocarcinoma to the kidney, the molecular era of renal cell carcinoma classification has enabled recognition of and provided tools for diagnosis of new entities in this morphologic differential. In this review, we consider these developments, with emphasis on renal medullary carcinoma, closely related renal cell carcinoma, unclassified with medullary phenotype, and fumarate hydratase-deficient renal cell carcinoma. Integration of ancillary studies with suggestive patterns of morphology is emphasized for practical implementation in contemporary diagnosis, and several emerging tumor types in the morphologic differential are presented.

Vimentin-positive gastric adenocarcinoma arising in a hyperplastic polyp

We report a case of vimentin-positive early gastric adenocarcinoma arising in a hyperplastic polyp (HP). A 72-year-old Japanese man was admitted for the detailed examination of a gastric polyp. He had a subtotal gastrectomy due to acute abdomen 12 years ago. Upper endoscopy revealed a pedunculated polyp measuring approximately 2 cm on the greater curvature of upper body of the remnant stomach. Magnifying endoscopy revealed that the microsurface pattern was irregular and partially absent accompanied with irregular microvessels at the upper end of the polyp. We speculated that the lesion was an adenocarcinoma arising in the HP. Endoscopic submucosal dissection (ESD) was performed. Histological examination of the ESD specimen revealed that the lesion consisted of well- to poorly differentiated adenocarcinoma at the protruding lesion and foveolar hyperplastic epithelia at the base of the polyp. Immunohistochemically, most of tumor cells that comprised poorly-differentiated adenocarcinoma were positive for both cytokeratin and vimentin. Although carcinomas have occasionally been found in HPs, the histological features of the present case are considered extremely unusual. To the best of our knowledge, this is the first case of vimentin-positive early gastric carcinoma arising in a HP.

Prognostic implications of sarcomatoid and rhabdoid differentiation in patients with grade 4 renal cell carcinoma

OBJECTIVE

Sarcomatoid and rhabdoid differentiation are associated with poor outcomes in renal cell carcinoma (RCC). We examined the impact of differentiation on cancer-specific survival (CSS) in surgically treated patients with grade 4 RCC.

MATERIALS AND METHODS

Using our institutional database of 1176 nephrectomies from 2005 to 2013, we identified patients with grade 4 RCC or any grade and the presence of sarcomatoid or rhabdoid differentiation. We divided the cohort based on differentiation: no differentiation, rhabdoid only, sarcomatoid only, and sarcomatoid and rhabdoid. CSS was analyzed using the Kaplan-Meier method and Cox proportional hazards modeling.

RESULTS

Of 264 patients with grade 4 RCC, 159 (60.2 %) exhibited differentiation, including 45 (28.3 %) with rhabdoid only, 87 (54.7 %) with sarcomatoid only, and 27 (16.9 %) with rhabdoid and sarcomatoid. Sarcomatoid differentiation, either alone or with rhabdoid differentiation, was associated with worse median CSS than no differentiation (1.1 vs. 3.3 years, p < 0.01, and 0.9 vs. 3.3 years, p < 0.01, respectively). In patients with non-metastatic (HR 1.95, 95 % CI 1.19-3.19, p = 0.008) and metastatic (HR 2.22, 95 % CI 1.45-3.41, p < 0.001) RCC, sarcomatoid differentiation was associated with an increased risk of cancer-specific death. On multivariable analysis, sarcomatoid differentiation was an independent predictor of RCC death in patients with non-metastatic (HR 1.72, 95 % CI 1.04-2.84, p = 0.03) and metastatic (HR 1.74, 95 % CI 1.05-2.90, p = 0.03) disease. Rhabdoid differentiation alone was not associated with worse CSS (p = 0.55).

CONCLUSIONS

In grade 4 RCC, sarcomatoid differentiation is associated with increased mortality risk across all stages of disease. Rhabdoid differentiation is not associated with additional mortality risk.

Diagnostic Accuracy of Renal Mass Biopsy

We investigated the diagnostic accuracy of renal mass biopsy in an ex vivo model, as well as compared the agreement of the preoperative radiological diagnosis with the final pathologic diagnosis. Two 18-gauge needle-core and 2 vacuum-needle biopsies were performed ex vivo from the tumors of 100 consecutive patients undergoing radical nephrectomy between 2006 and 2010. The median tumor size was 5.5 cm. There was no significant difference with regard to cylinder length or tissue quality between the sampling methods. At least 1 of 4 needle cores contained diagnostic tissue in 88% of patients. Biopsy specimens identified clear cell (54%), papillary (13%), or chromophobe (5%) renal cell carcinoma; urothelial carcinoma (6%); oncocytoma (5%); liposarcoma (1%); metastatic colorectal carcinoma (1%); squamous cell carcinoma (1%); unclassified renal cell neoplasm (1%); and no tumor sampled (12%). The sensitivity of the biopsy for accurately determining the diagnosis was 88% (95% CI: 79% to 93%). The specificity was 100% (95% CI: 17% to 100%). Biopsy grade correlated strongly with final pathology (83.5% agreement). There was no difference in average tumor size in cases with the same versus higher grade on final pathology (5.87 vs 5.97; P = .87). Appraisal of tumor histology by radiology agreed with the pathologic diagnosis in 68% of cases. Provided that the biopsy samples the tumor tissue in a renal mass, pathologic analysis is of great diagnostic value in respect of grade and tumor type and correlates well with excisional pathology. This constitutes strong ground for increasingly used renal mass biopsy in patients considering active surveillance or ablation therapy.

Impact of Rhabdoid Differentiation on Prognosis for Patients with Grade 4 Renal Cell Carcinoma

Renal cell carcinoma (RCC) with rhabdoid differentiation is thought to portend a poor prognosis, similar to RCC with sarcomatoid differentiation. Both features are currently classified as grade 4 RCC based on the most recent International Society of Urological Pathology (ISUP) grading system. We reviewed a large series of patients with grade 4 RCC to determine the differential effects of rhabdoid and sarcomatoid differentiation on patient outcome. We identified 406 patients with ISUP grade 4 RCC including 111 (27%) with rhabdoid differentiation. In multivariable analysis of grade 4 RCC tumors, the presence of rhabdoid differentiation was not associated with death from RCC (hazard ratio [HR]: 0.95; p=0.75); in contrast, sarcomatoid differentiation was significantly associated with death from RCC (HR: 1.63; p<0.001). Patients with RCC with rhabdoid differentiation were significantly more likely to die of RCC than a comparison cohort of 1758 patients with grade 3 RCC (HR: 2.45; p<0.001). The novel findings of our study suggest that rhabdoid and sarcomatoid differentiation should not be grouped together when assessing risk in a patient with grade 4 RCC but support the notion that rhabdoid differentiation is appropriately placed in the ISUP grade 4 category.

Concurrent occurrence of renal cell carcinoma with rhabdoid features in a married couple: a case report

Background

Renal cell carcinoma (RCC) with rhabdoid features is a rare histology and exhibits clinically aggressive behavior. We report a case of a married couple in whom RCC with rhabdoid features concurrently occurred. The rarity of this event suggests that environmental factors may contribute to the etiology of RCC with rhabdoid features.

Case presentation

A 76-year-old Japanese woman was diagnosed with a hypervascular mass in the right kidney and tumor thrombus extending into the right atrium by enhanced computed tomography (CT). She underwent radical nephrectomy and tumor thrombectomy following systemic therapy with the tyrosine kinase inhibitor sunitinib. The histological evaluation denoted clear cell RCC with rhabdoid features. The patient died of cancer 12 months postoperatively. A 76-year-old man, her husband, presented with gross hematuria 2 weeks after his wife had undergone surgery. He had a long history of asbestos exposure. An abdominal CT scan revealed a hypervascular mass in the right kidney and tumor thrombus extending into the inferior vena cava. He also underwent radical nephrectomy and tumor thrombectomy. The histological evaluation also showed clear cell RCC with rhabdoid features. Bone metastasis occurred 12 months postoperatively, but he died of an unrelated cause 18 months after surgery.

Conclusion

Concurrent occurrence of RCC with rhabdoid features may not to be coincidental. Although further studies are warranted, asbestos exposure may contribute to the etiology of clear cell RCC with rhabdoid features.