Renal cell carcinoma associated with transcription factor E3 expression and Xp11.2 translocation: incidence, characteristics, and prognosis

Four years of natural progressive course: A rare case report of juvenile Xp11.2 translocations renal cell carcinoma with TFE3 gene fusion

Background

Renal cell carcinoma (RCC) with TFE3 gene fusion caused by Xp11.2 translocations is a rare RCC subtype. This tumor is typically seen in children, comprising 20‒40% of overall RCC cases compared to 1‒1.6% observed in adults. Xp11.2 RCC is associated with a poor prognosis due to both the progression of local lesions and early distant and lymphatic metastasis.

Case presentation

A case of RCC with Xp11.2 RCC translocations and TFE3 gene fusion was found in a pediatric patient, illustrating the catastrophic effects of ignoring the condition. The tumor developed from a local lesion to lymph metastasis (3.2-12 cm) within 4 years. Despite ongoing controversy, surgical resection remains the most common and productive approach. In this patient, renal retroperitoneal lymph node dissection and radical nephrectomy of the left kidney were performed via laparoscopic surgery. The RCC-associated Xp11.2 translocation/TFE3 gene fusions were identified by postoperative pathology. Microscopic analysis showed the presence of intravascular cancer thrombus, renal sinus invasion, and cancer necrosis. The pathological stages were confirmed as PT3aN1M0 with a negative margin. Follow-up at 5 months showed that the patient recovered without the use of any adjuvant treatments.

Conclusion

Our study highlights the natural course, diagnosis, and treatment of RCC-associated Xp11.2 translocation/TFE3 gene fusions, especially the necessity of early surgery. This case may be a helpful reference for urologists in the treatment of similar cases. It also serves as a precautionary signal for patients who neglect the renal neoplasm.

Therapeutic strategies and predictive models for Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma in adults based on data of two Chinese medical centers

OBJECTIVE

This study aims to establish an effective predictive model for predicting Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma (TFE3-RCC) and develop optimal therapeutic strategies.

METHODS

Data from 4961 patients diagnosed with renal cell carcinoma at two medical centers in China were retrospectively analyzed. A cohort of 1571 patients from Zhejiang Provincial People's Hospital (Ra cohort) was selected to construct the model. Another cohort of 1124 patients from the Second Affiliated Hospital of Zhejiang Chinese Medical University was used for external validation (the Ha cohort). All patients with TFE3-RCC in both cohorts were included in the Ta cohort for the prognostic analysis. Univariate and multivariate binary logistic regression analyses were performed to identify independent predictors of the predictive nomogram. The apparent performance of the model was validated. Decision curve analysis was also performed to assess the clinical utility of the developed model. Factors associated with progression and prognosis in the Ta cohort were analyzed using the log-rank method, and Cox regression analysis and Kaplan-Meier survival curves were used to describe the effects of factors on prognosis and progression.

RESULTS

Univariate and multivariate logistic regression analyses demonstrated that age, sex, BMI, smoking, eosinophils, and LDL were independent predictors of TFE3-RCC. Therefore, a predictive nomogram for TFE3-RCC, which had good discriminatory power (AUC = 0.796), was constructed. External validation (AUC = 0.806) also revealed good predictive ability. The calibration curves displayed good consistency between the predicted and observed incidences of TFE3-RCC. Invasion of regional lymph nodes, tyrosine kinase inhibitors, and surgical methods were independent factors associated with progression. Tyrosine kinase inhibitors are independent prognostic factors.

CONCLUSION

This study not only proposed a high-precision clinical prediction model composed of various variables for the early diagnosis of Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma but also optimized therapeutic strategies through prognostic analysis.

Immunohistochemical expression of cytochrome P4A11 (CYP4A11), carbonic anhydrase 9 (CAIX) and Ki67 in renal cell carcinoma; diagnostic relevance and relations to clinicopathological parameters

BACKGROUND

Cytochrome P4A11 (CYP4A11) is a member of cytochrome p450 family, which is involved in arachidonic acid metabolism that participates in promoting malignant cell proliferation, progression, and angiogenetic capacity. Carbonic Anhydrase 9 (CAIX) is a transmembrane protein that plays an integral part in regulating hypoxia which affects cancer cell metabolism, proliferation and promotes metastasis. The aim of this study was to evaluate the immunohistochemical expression of CYP4A11, CAIX and ki67 in RCC subtypes in relation to clinicopathological parameters and to evaluate the diagnostic significance of CYP4A11 and CAIX in differentiating renal cell carcinoma (RCC) subtypes.

MATERIALS AND METHODS

one hundred primary RCC cases, collected from Pathology Department, Faculty of Medicine, Tanta University and from private laboratories, were evaluated for immunohistochemical expression of CYP4A11, CAIX and ki67.

RESULTS

CYP4A11 was expressed in 59% of RCC; with 91.7% sensitivity and 90% specificity in differentiating clear cell and non-clear cell subtypes. CAIX was expressed in 50% of RCC; with 95% sensitivity, 80% specificity. High expression of CYP4A11 was statistically positively associated with higher tumor grade, high expression of CAIX was statistically positively associated with lower tumor grade and absence of necrosis and high ki67 labeling index was significantly associated with clear cell subtype, larger tumor sizes, higher tumor grade, advanced tumor stage, fat invasion and vascular invasion.

CONCLUSIONS

CYP4A11 and CAIX can be used as diagnostic markers to differentiate clear cell RCC from other subtypes. CYP4A11 is more diagnostically accurate and specific than CAIX. High expression of CYP4A11, low CAIX expression and high ki67 labeling index were related to features of aggressive tumor behavior.

A safe and effective treatment combination of neoadjuvant therapy and surgical resection for metastatic TFE3-rearranged renal cell carcinoma:a case report

TFE3-rearranged renal cell carcinoma (RCC) is a rare subtype of renal tumor that primarily affects young women and is characterized by early metastasis and a poor prognosis. This case study presents a 29-year-old woman diagnosed with TFE3-rearranged RCC, who initially presented with painless gross hematuria. Computed Tomography (CT) imaging revealed the presence of a solid mass in the left kidney along with retroperitoneal metastasis. The patient received axitinib, a vascular endothelial growth factor receptor-tyrosine kinase inhibitor (VEGFR-TKI), as first-line neoadjuvant therapy. Subsequent testing confirmed positive expression of programmed death-1 protein L1 (PDL1), leading to the addition of tislelizumab, a PD1 inhibitor, to the treatment regimen. After 8 months, the patient's tumor size and metastases exhibited significant reduction, providing a favorable opportunity for subsequent surgical intervention. The tumor was classified as IV (pT3aN0M1) based on the pathologic stage of the American Joint Committee on Cancer (AJCC, 8th edition, 2017). The patient achieved long-term survival through combined systemic therapy involving surgery and neoadjuvant treatment. At the 30-month follow-up, there was no evidence of tumor recurrence or metastasis.

Multimodality imaging of Xp11.2 translocation/TFE3 gene fusion associated with renal cell carcinoma: a case report

Background

Xp11.2 translocation/TFE3 gene fusion associated with renal cell carcinoma (Xp11.2 RCC) exhibits unique biological characteristics and is associated with an increased incidence of tumor thrombosis, lymph node metastasis, and advanced disease stages. Multimodality imaging, including US, contrast-enhanced CT, multi-parametric MRI, and 18F-FDG PET/CT plays a crucial role in the preoperative diagnosis and differentiation of renal tumors.

Case report

A 15-year-old female presented with lumbar pain worsened, and developed persistent painless hematuria. The CT attenuation values of the scan without contrast, corticomedullary phase, nephrographic phase, and delayed phases were 35 HU, 83 HU, 82 HU, and 75 HU, respectively. The solid component of the mass displayed heterogeneous marked enhancement. Furthermore, MRU indicated that the lesion involved the cortical medulla and infringed on the renal sinus fat. The lesion appeared isosignal in T1WI, slightly low signal in T2WI, and slightly high signal in DWI. The degree of enhancement in the three phases of enhancement scan was lower than that in the renal parenchyma, and hemorrhage and necrosis were observed within the internal part of the lesion. To further clarify the staging, the patient underwent 18F-FDG PET/CT. PET/CT images showed multiple irregular occupancies in the right kidney with unclear borders, showing a heterogeneous increase in 18F-FDG uptake, with SUVmax values ranging from 2.3 to 5.2 in the routine imaging phase (60 min post-injection), compared to SUVmax values ranging from 2.8 to 6.9 in the delayed imaging phase (160 min post-injection). Additionally, multiple enlarged and fused lymph nodes were observed in the medial part of the right kidney and the retroperitoneum, exhibiting a heterogeneous increase in 18F-FDG uptake, with SUVmax values ranging from 4.1 to 8.7 in the routine imaging phase, compared to SUVmax values ranging from 4.4 to 9.1 in the delayed imaging phase. The postoperative pathology, immunohistochemistry, and molecular analysis of histiocytes were consistent with a diagnosis of Xp11.2 RCC. One month after surgery, enhanced-CT examination of the patient revealed lung metastasis, peritoneal metastasis, and multiple lymph node metastases throughout the body, with an overall survival of 16 months.

Conclusion

Xp11.2 RCC exhibits unique biological characteristics and is associated with an increased incidence of tumor thrombosis, lymph node metastasis, and advanced disease stages. Long-term follow-up is essential to monitor the likelihood of recurrence and metastasis. 18F-FDG PET/CT examination can comprehensively visualize the lesion's location and extent, providing a basis for clinical tumor staging and aiding in treatment monitoring and follow-up. To address the limitations of FDG, the utilization of specific tracers designed for RCC or tracers that are not excreted via the urinary system would be ideal. Further advancements in molecular imaging technologies and the development of novel tracers hold great promise in advancing the diagnosis and management of RCC, ultimately contributing to better patient outcomes and overall disease management.

The Transition From Localized to Metastatic: A Case Report of Adult TFE3-Positive Xp11.2 Translocation Renal Cell Carcinoma

Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) is a rare tumor, occurring more frequently in childhood than in adulthood. It results from Xp11.2 chromosome translocations and the fusion of the transcription factor E3 (TFE3) gene. In this context, we present a case report of an 18-year-old female who was diagnosed with Xp11.2 RCC following open radical nephrectomy and lymph node dissection on the left side. The histopathological analysis indicated stage T3aN1Mx disease, which was confirmed through immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH). The patient remained under observation until March 2023 when systemic scans uncovered the presence of ascites, peritoneal carcinomatosis, and left supraclavicular lymphadenopathy. A subsequent biopsy reaffirmed the primary disease, leading to the planning of systemic treatment involving tyrosine kinase inhibitors (TKIs) and immunotherapy. However, due to financial constraints, the patient's treatment options were limited to sunitinib initially. The current plan involves reevaluation after three months using scans to determine the subsequent course of treatment. Our case report offers crucial insights into the clinical presentation, diagnosis, and treatment of this rare malignancy. This enhances medical understanding, guides research, and improves the management of similar cases. Case reports like this share practical experiences, shaping future studies and patient care.

Clinicopathological features and prognosis of TFE3-positive renal cell carcinoma

Background

This study aimed to investigate the expression profile of TFE3 in renal cell carcinoma (RCC) and the clinicopathological features as well as prognosis of TFE3-positive RCC.

Methods

Tissue sections from 796 patients with RCC were collected for immunohistochemical staining of TFE3. Molecular TFE3 rearrangement tests were also carried out on the TFE3-positive RCCs using fluorescence in situ hybridization and RNA-sequencing assays. Both clinicopathological features and follow-up information were collected for further analysis.

Results

The present study showed that 91 patients with RCC (91/796, 11.4%) were TFE3 positive expression but only 31 (31/91, 34.1%) of the patients were diagnosed with Xp11.2 translocation RCC. Further, it was found that the patients with TFE3-positive RCCs were more likely to develop lymph node and distant metastasis at diagnosis as well as presented a significantly higher WHO/ISUP nuclear grade and AJCC stage as compared with patients with TFE3-negative RCCs (p<0.01). Results of univariate and multivariate analyses showed that TFE3 positive expression was an independent prognostic factor associated with poor progression-free survival. Further, the findings of survival analysis showed that patients with positive TFE3 expression showed a shorter progression-free survival as compared with the patients with negative expression of TFE3 (p<0.001). In addition, results of the survival analysis found that there was no significant difference in progression-free survival between the Xp11.2 translocation RCC and TFE3-positive non-Xp11.2 translocation RCC groups (p=0.9607).

Conclusion

This study found that nuclear TFE3 expression is not specific to the Xp11.2 translocation RCC. Moreover, the positive TFE3 expression is associated with tumor progression and poor prognosis in patients with RCC irrespective of the presence of TFE3 translocation.

Case Report: Clinical complete response of advanced renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion by treated by camrelizumab and axitinib: A rare case report

Renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusions is a rare subtype of renal tumor. This entity predominantly occurs in juveniles, but rarely in adults. Xp11.2 translocation RCC (tRCC) patients with lymph node or organ metastasis are associated with poor prognosis, and the strategy remains controversial. Herein, we presented our experience with the diagnosis and treatment of an adult case of Xp11.2 tRCC. In our clinical practice, a 32-year-old male manifested fever and right flank paroxysmal blunt pain, and computed tomography showed an inhomogeneous mass, 6 cm in diameter, in the right kidney. Then right partial nephrectomy (PN) and renal hilar lymph node dissection by laparoscopic surgery were performed. Pathology revealed that the tumor cells were positive for TFE3 immunohistologically and positive for TFE3 break-apart fluorescence in situ hybridization assay. A splice site mutation c.1544-1G>T of protein tyrosine phosphatase receptor delta (PTPRD) was detected by next-generation sequencing and weak PTPRD expression was confirmed in tumor tissues compared to tumor periphery. This patient was diagnosed with stage III RCC and received immune checkpoint inhibitor (camrelizumab) in combination with tyrosine kinase inhibitor (axitinib) treatment for 1 year. He achieved a clinical complete response with no sign of recurrence or metastasis. PTPRD mutation might be a favorable indicator for Xp11.2 tRCC patients managed by PN and followed by the adjuvant therapy of immune checkpoint inhibitor and tyrosine kinase inhibitor.

Clinicopathologic, treatment and prognosis study of 46 Xp11.2 translocation/TFE3 gene fusion renal cell carcinomas

PURPOSE

To report the clinicopathological features and mid- to long-term oncologic results of Xp11.2 translocation/transcription factor E3 (TFE3) gene fusion renal cell carcinomas (Xp11.2 translocation RCCs) in a single large-volume centrecentre.

METHODS

Clinical and follow-up data of 46 patients who were diagnosed with Xp11.2 translocation RCC and underwentunderwent surgical intervention were retrospectively reviewed.

RESULT

Forty-six Xp11.2 translocation RCC patients were identified from 4218 renal tumour patients who were underwentunderwent surgery in our centrecentre from Jan. 2014 to Apr. 2020. The incidence of Xp11.2 translocation RCCs in our centre was 1.09%. During a median follow-up period of 30.5 months, 4 patients died of the disease. The total median overall survival and cancer specific survival were 30.0 months and 24.0 months, respectively. The 1-year, 3-year and 5-year OS rates were 97.4%, 88.8%, and 88.8%, respectively. In multivariable analysis, displaying symptoms when diagnosed (p = 0.019), lymph node metastasis (p = 0.002) and distal metastasis (p = 0.020) were identified as risk factors for poor prognosis.

CONCLUSION

Xp11.2 translocation RCC is a type of renal cell carcinoma with a relatively low incidence and various prognoses. Early-stage Xp11.2 translocation RCCs have a similar prognosis to most typical RCCs, but late-stage Xp11.2 translocation RCCs can lead to poor oncological outcomes.

Key Renal Neoplasms With a Female Predominance

Renal neoplasms largely favor male patients; however, there is a growing list of tumors that are more frequently diagnosed in females. These tumors include metanephric adenoma, mixed epithelial and stromal tumor, juxtaglomerular cell tumor, mucinous tubular and spindle cell carcinoma, Xp11.2 (TFE3) translocation-associated renal cell carcinoma, and tuberous sclerosis complex (somatic or germline) associated renal neoplasms. The latter category is a heterogenous group with entities still being delineated. Eosinophilic solid and cystic renal cell carcinoma is the best-described entity, whereas, eosinophilic vacuolated tumor is a proposed entity, and the remaining tumors are currently grouped together under the umbrella of tuberous sclerosis complex/mammalian target of rapamycin-related renal neoplasms. The entities described in this review are often diagnostic considerations when evaluating renal mass tissue on biopsy or resection. For example, Xp11.2 translocation renal cell carcinoma is in the differential when a tumor has clear cell cytology and papillary architecture and occurs in a young or middle-aged patient. In contrast, tuberous sclerosis complex-related neoplasms often enter the differential for tumors with eosinophilic cytology. This review provides an overview of the clinical, gross, microscopic, immunohistochemical, genetic, and molecular alterations in key renal neoplasms occurring more commonly in females; differential diagnoses are also discussed regardless of sex predilection.

TAZ-CAMTA1 and YAP-TFE3 alter the TAZ/YAP transcriptome by recruiting the ATAC histone acetyltransferase complex

Epithelioid hemangioendothelioma (EHE) is a vascular sarcoma that metastasizes early in its clinical course and lacks an effective medical therapy. The TAZ-CAMTA1 and YAP-TFE3 fusion proteins are chimeric transcription factors and initiating oncogenic drivers of EHE. A combined proteomic/genetic screen in human cell lines identified YEATS2 and ZZZ3, components of the Ada2a-containing histone acetyltransferase (ATAC) complex, as key interactors of both fusion proteins despite the dissimilarity of the C terminal fusion partners CAMTA1 and TFE3. Integrative next-generation sequencing approaches in human and murine cell lines showed that the fusion proteins drive a unique transcriptome by simultaneously hyperactivating a TEAD-based transcriptional program and modulating the chromatin environment via interaction with the ATAC complex. Interaction of the ATAC complex with both fusion proteins indicates that it is a key oncogenic driver and unifying enzymatic therapeutic target for this sarcoma. This study presents an approach to mechanistically dissect how chimeric transcription factors drive the formation of human cancers.

The proliferation of human cells is tightly regulated to ensure that enough cells are made to build and repair organs and tissues, while at the same time stopping cells from dividing uncontrollably and damaging the body. To get the right balance, cells rely on physical and chemical cues from their environment that trigger the biochemical signals that regulate two proteins called TAZ and YAP. These proteins control gene activity by regulating the rate at which genes are copied to produce proteins. If this process becomes dysregulated, cells can grow uncontrollably, causing cancer.

In cancer cells, it is common to find TAZ and YAP fused to other proteins. In epithelioid hemangioendothelioma, a rare cancer that grows in the blood vessels, cancerous growth can be driven by a version of TAZ fused to the protein CAMTA1, or a version of YAP fused to the protein TFE3. While the role of TAZ and YAP in promoting gene activity is known, it is unclear how CAMTA1 and TFE3 contribute to cell growth becoming dysregulated.

Merritt, Garcia et al. studied sarcoma cell lines to show that these two fusion proteins, TAZ-CAMTA1 and YAP-TFE3, change the pattern of gene activity seen in the cells compared to TAZ or YAP alone. An analysis of molecules that interact with the two fusion proteins identified a complex called ATAC as the cause of these changes. This complex adds chemical markers to DNA-packaging proteins, which control which genes are available for activation. The fusion proteins combine the ability of TAZ and YAP to control gene activity and the ability of CAMTA1 and TFE3 to make DNA more accessible, allowing the fusion proteins to drive uncontrolled cancerous growth.

Similar TAZ and YAP fusion proteins have been found in other cancers, which can activate genes and potentially alter DNA packaging. Targeting drug development efforts at the proteins that complex with TAZ and YAP fusion proteins may lead to new therapies.

The positive regulation loop between NRF1 and NONO-TFE3 fusion promotes phase separation and aggregation of NONO-TFE3 in NONO-TFE3 tRCC

TFE3 gene fusions often place TFE3 under the control of a more active promoter and cause overexpression of the TFE3 proteins in renal cell carcinoma associated with Xp11.2 translocations (Xp11.2 tRCC). The purpose of this study was to investigate the transcriptional regulation and aggregation mechanism of NONO-TFE3 in NONO-TFE3 tRCC. In this study, we found that the nuclear aggregation of NONO-TFE3 fusion was significantly more than that of intact TFE3 or PRCC-TFE3 fusion. We observed that NONO fragment mediated-phase separation promoted stabilization and aggregation of NONO-TFE3 fusion. Meantime, we revealed that the positive regulation loop between NONO-TFE3 and NRF1 increased mitochondrial biosynthesis and metabolism in NONO-TFE3 tRCC. Therefore, the present study raises the possibility that mitochondrial metabolism is potentially a fruitful arena for NONO-TFE3 tRCC therapy.

MiT family translocation renal cell carcinoma in an elderly male

Translocation-associated renal cell carcinoma (t-RCC) is a relatively uncommon subtype of renal cell carcinoma characterized by recurrent gene rearrangements involving the TFE3 or TFEB loci. TFE3 and TFEB are members of the microphthalmia transcription factor (MiT) family, which regulate differentiation in melanocytes and osteoclasts. Renal cell carcinomas (RCCs) associated with Xp11 translocations have gene fusions involving TFE3, which has multiple gene partners; RCCs with t(6:11) translocations have MALAT1-TFEB gene fusions. These tumors are histologically diverse, often have papillary, alveolar, and nested growth pattern with clear and eosinophilic cells and psammoma bodies and are seen commonly in children and young adults, accounting to 40% of pediatric RCCs and 1.6%-4% of adult RCCs. The mean and median patient age is 31 years. Thus, distinguishing t-RCC from its morphologic, immunophenotypic, and molecular mimics has important clinical implications. Directed ancillary testing is an essential aspect to t-RCC cases and may include a panel of immunohistochemical stains, such as PAX8, pancytokeratins, AMACR, CD10, and TFE-3. We, hereby report a case of TFE3 positiveXp11 translocation renal cell carcinoma in a 52-year-old male which is unusual.

Genomic profiling in renal cell carcinoma

The treatment landscape of metastatic renal cell carcinoma (RCC) has been revolutionized over the past two decades, bringing forth an era in which more than a dozen therapeutic agents are now available to treat patients. As a consequence, personalized care has become a critical part of developing effective treatment guidelines and improving patient outcomes. One of the most important emerging aspects of precision medicine in cancer is matching patients and treatments based on the genomic characteristics of an individual and their tumour. Despite the lack of a single genomic predictor of treatment response or prognostication feature in RCC, emerging research suggests that the identification of such markers remains promising. Mutations in VHL and alterations in its downstream pathways are the mainstay of RCC development and progression. However, the predictive value of VHL mutations has been questioned. Further research has examined mutations in genes involved in chromosome remodelling (for example, PBRM1, BAP1 and SETD2), DNA methylation and DNA damage repair, all of which have been associated with clinical outcomes. Here, we provide a comprehensive overview of genomic evidence in the context of RCC and its potential predictive and prognostic value.

Anti-angiogenesis and Immunotherapy: Novel Paradigms to Envision Tailored Approaches in Renal Cell-Carcinoma

Although decision making strategy based on clinico-histopathological criteria is well established, renal cell carcinoma (RCC) represents a spectrum of biological ecosystems characterized by distinct genetic and molecular alterations, diverse clinical courses and potential specific therapeutic vulnerabilities. Given the plethora of drugs available, the subtype-tailored treatment to RCC subtype holds the potential to improve patient outcome, shrinking treatment-related morbidity and cost. The emerging knowledge of the molecular taxonomy of RCC is evolving, whilst the antiangiogenic and immunotherapy landscape maintains and reinforces their potential. Although several prognostic factors of survival in patients with RCC have been described, no reliable predictive biomarkers of treatment individual sensitivity or resistance have been identified. In this review, we summarize the available evidence able to prompt more precise and individualized patient selection in well-designed clinical trials, covering the unmet need of medical choices in the era of next-generation anti-angiogenesis and immunotherapy.

[MiT family translocation renal cell carcinomas: Natural history, molecular features and multidisciplinary management]

MiT family translocation renal cell carcinomas (tRCC) represent a rare subtype of renal cell carcinomas. These tumors have been introduced for the first time in the World Health Classification (WHO) classification of kidney cancers in 2004. tRCC are characterized by reccurent translocations involving members of the MiT family transcription factors, mainly TFE3 and TFEB. The estimated incidence of these tumors is ∼1-5 % among all renal cell carcinomas, with female prodominance. tRCC were initially described in children, and the spectrum has been expanded over time to encompass adolescents and adults. TFE3- and TFEB-rearranged RCC harbor characteristic clinicopathological and immunohistochemical features and fluorescent hybridization in situ is considered the gold standard for their diagnosis, although it has some limitations especially when the partners are located in the vicinity of TFE3. Nephron-sparing surgery is an efficient treatment of localized cases when achievable. In metastatic setting, targeted agents and immunotherapy showed modest efficacy, with response rates and median overall survival inferior to those observed in clear-cell renal cell carcinomas. Management of tRCC necessite a multidisciplinary team and accrual in clinical trials have to be encouraged when possible. Novel biological insights are urgently awaited to better understand the mechanisms associated with kidney oncogenesis in this setting, and ultimately help to identify therapeutic targets.

Contrast-enhanced ultrasound findings of adult renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion: comparison with clear cell renal cell carcinoma and papillary renal cell carcinoma

BACKGROUND

To investigate the contrast-enhanced ultrasound (CEUS) findings of renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusion (Xp11.2/TFE3) in adult patients by comparison with those of clear cell RCC (ccRCC) and papillary RCC (pRCC).

METHODS

In total, 110 patients (110 renal masses) who underwent CEUS examinations were enrolled in this study. The cases included 18 Xp11.2/TFE3 RCCs, 60 ccRCCs and 32 pRCCs. All masses were confirmed by operative pathology. The CEUS imaging data of these patients were retrospectively analysed by two readers. The conventional US and CEUS features of Xp11.2/TFE3 RCC were compared with those of ccRCC and pRCC.

RESULTS

The age of the patients with Xp11.2/TFE3 RCC ranged from 20 to 68 years, with a mean age of 38.3 ± 16.3 years and a slight female predominance. The weighted kappa value that interprets the concordance between the interobserver agreement of the US and CEUS features ranged from 0.61 to 0.89. On conventional US and CEUS imaging of Xp11.2/TFE3 RCCs, the tumours were hypoechoic (6/18, 33.3%), isoechoic (8/18, 44.4%), and hyperechoic (4/18, 22.2%). The cystic component was present in 5 cases (27.8%), calcification was present in 9 cases (50.0%), and colour flow signal was present in 7 cases (38.9%). Most cases showed simultaneous wash-in (11/18, 61.1%); the peak enhancement showed hypoenhancement (6/18, 33.3%), isoenhancement (10/18, 55.6%), and hyperenhancement (2/18, 11.1%); most cases exhibited heterogeneous enhancement (12/18, 66.7%) and fast- or simultaneous-out (16/18, 88.9%); and a pseudocapsule was present in 6 cases (33.3%). In the multivariate logistic regression analysis, calcification and lower peak enhancement were more likely to be present in Xp11.2/TFE3 RCC than in ccRCC (P < 0.05), and younger age and relatively high peak enhancement were more likely to be present in Xp11.2/TFE3 RCC than in pRCC (P < 0.05). The calcification combined peak enhancement model differentiated Xp11.2/TFE3 RCC from ccRCC, and the age combined peak enhancement model differentiated Xp11.2/TFE3 RCC from pRCC with an AUC, a sensitivity and a specificity of 0.896, 94.4% and 73.3% and 0.786, 50.0% and 100.0%, respectively.

CONCLUSIONS

The specific CEUS features combined with demographic information and clinical symptoms may be helpful for differentiating Xp11.2/TFE3 RCC from ccRCC and pRCC.

Eosinophilic Kidney Tumors: Old and New

Context.—

Eosinophilic cytoplasm is the most common finding of difficult-to-classify kidney tumors. Morphology, cytogenetics, and immunohistochemical stains are discriminatory. This review compares well-recognized tumors such as granular clear cell carcinoma, papillary variants, chromophobe renal cell carcinoma, and oncocytoma and introduces newly described entities of hybrid oncocytic tumors, carcinomas defined by translocations, and carcinomas with deficiencies in the tricarboxylic acid cycle. The focus is on immunostaining, clinical correlations, and differential diagnoses. Representative examples of some entities are presented with elaboration on their workup.

Objective.—

To provide a review of the differential diagnoses for renal neoplasms with eosinophilic cytoplasm and elaborate on methods that may assist with correct identification.

Data Sources.—

Review of current literature on kidney tumors with eosinophilic cytoplasm, as well as the authors' personal experience.

Conclusions.—

Eosinophilic cytoplasm is a feature shared by many kidney tumors. Understanding the morphologic differences and the role of ancillary studies is key when encountering such a tumor.

Incidence and significance of psammoma bodies in Xp11.2 translocation renal cell carcinoma and papillary renal cell carcinoma

The aim of the present study was to investigate the incidence and significance of psammoma bodies (PBs) in Xp11.2 translocation renal cell carcinoma (Xp11.2 tRCC) and papillary renal cell carcinoma (PRCC). The presence of PBs, irregular calcifications, hyaline globules and nested architecture in RCC tissues, which included 47 cases of Xp11.2 tRCC and 95 cases of PRCC, was examined by two pathologists. Compared with PRCC, patients with Xp11.2 tRCC exhibited a higher frequency of PBs, hyaline globules and nested architecture. The presence of PBs in combination with the occurrence of a nested architecture achieved a specificity of 93.7% when diagnosing Xp11.2 tRCC. However, there were no significant differences in the overall survival between patients with and without PBs in both types of RCC. Therefore, the presence of PBs combined with nested architecture may provide guidance for the diagnosis of Xp11.2 tRCC; however, PBs cannot predict tumor behavior in Xp11.2 tRCC or PRCC.

RBM10-TFE3 renal cell carcinoma characterised by paracentric inversion with consistent closely split signals in break-apart fluorescence in-situ hybridisation: study of 10 cases and a literature review

AIMS

Xp11 rearrangement in renal cell carcinoma (RCC) typically involves gene fusion to the gene encoding transcription factor E3 (TFE3), a member of the microphthalmia-associated transcription factor family on chromosome Xp11.2. Dual-colour break-apart fluorescence in-situ hybridisation (FISH) is recommended to confirm histological diagnoses. Recently, RNA-binding motif protein 10 (RBM10), encoded by a gene on chromosome Xp11.3, was identified as a chimeric partner of TFE3; thus, RBM10-TFE3 fusion results from paracentric inversion. RBM10-TFE3 RCC may yield a false-negative result in FISH analysis of TFE3 expression. The aim of the present study was to investigate the clinicopathological features of RBM10-TFE3 RCC.

METHODS AND RESULTS

Ten patients with RBM10-TFE3 RCC aged 31-71 years were investigated. Histological analysis, immunostaining, dual-colour break-apart FISH for TFE3, reverse transcription polymerase chain reaction and sequencing analysis were performed. No patient had a history of exposure to chemotherapy. Two of these patients died of RCC, and three were alive but developed metastases. Microscopically, the tumours were composed of a mixed architecture of tubulocystic and papillary patterns with scattered psammoma bodies. The tumours showed strong nuclear immunoreactivity for TFE3. FISH showed consistent closely spaced split signals in the RCCs of four patients, and polysomic signals with occasional closely spaced split signals in the RCCs of six patients. Of the latter six patients, five had renal failure, and four developed tumours in kidneys subjected to haemodialysis.

CONCLUSIONS

The present study suggests that the carcinogenesis of RBM10-TFE3 RCC in some, but not all, patients may be associated with chronic kidney disease. The aggressive nature of RBM10-TFE3 RCC should be considered, as five patients experienced metastases.

Uncommon malignant renal tumors and atypical presentation of common ones: a guide for radiologists

OBJECTIVE

While the typical imaging features of the more common RCC subtypes have previously been described, they can at times have unusual, but distinguishing features. Rarer renal tumors span a broad range of imaging features, but they may also have characteristic presentations. We review the key imaging features of atypical presentations of malignant renal tumors and uncommon malignant renal tumors.

CONCLUSION

Renal tumors have many different presentation patterns, but knowledge of the distinguishing MR and CT features can help identify both atypical presentation of common malignancies and uncommon renal tumors.

RNA sequencing of Xp11 translocation-associated cancers reveals novel gene fusions and distinctive clinicopathologic correlations

Both Xp11 translocation renal cell carcinomas and the corresponding mesenchymal neoplasms are characterized by a variety of gene fusions involving TFE3. It has been known that tumors with different gene fusions may have different clinicopathologic features; however, further in-depth investigations of subtyping Xp11 translocation-associated cancers are needed in order to explore more meaningful clinicopathologic correlations. A total of 22 unusual cases of Xp11 translocation-associated cancers were selected for the current study; 20 cases were further analyzed by RNA sequencing to explore their TFE3 gene fusion partners. RNA sequencing identified 17 of 20 cases (85%) with TFE3-associated gene fusions, including 4 ASPSCR1/ASPL-TFE3, 3 PRCC-TFE3, 3 SFPQ/PSF-TFE3, 1 NONO-TFE3, 4 MED15-TFE3, 1 MATR3-TFE3, and 1 FUBP1-TFE3. The results have been verified by fusion fluorescence in situ hybridization (FISH) assays or reverse transcriptase polymerase chain reaction (RT-PCR). The remaining 2 cases with specific pathologic features highly suggestive of MED15-TFE3 renal cell carcinoma were identified by fusion FISH assay. We provide the detailed morphologic and immunophenotypic description of the MED15-TFE3 renal cell carcinomas, which frequently demonstrate extensively cystic architecture, similar to multilocular cystic renal neoplasm of low malignant potential, and expressed cathepsin K and melanotic biomarker Melan A. This is the first time to correlate the MED15-TFE3 renal cell carcinoma with specific clinicopathologic features. We also report the first case of the corresponding mesenchymal neoplasm with MED15-TFE3 gene fusion. Additional novel TFE3 gene fusion partners, MATR3 and FUBP1, were identified. Cases with ASPSCR1-TFE3, SFPQ-TFE3, PRCC-TFE3, and NONO-TFE3 gene fusion showed a wide variability in morphologic features, including invasive tubulopapillary pattern simulating collecting duct carcinoma, extensive calcification and ossification, and overlapping and high columnar cells with nuclear grooves mimicking tall cell variant of papillary thyroid carcinoma. Furthermore, we respectively evaluated the ability of TFE3 immunohistochemistry, TFE3 FISH, RT-PCR, and RNA sequencing to subclassify Xp11 translocation-associated cancers. In summary, our study expands the list of TFE3 gene fusion partners and the clinicopathologic features of Xp11 translocation-associated cancers, and highlights the importance of subtyping Xp11 translocation-associated cancers combining morphology, immunohistochemistry, and multiple molecular techniques.

Adult-onset renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion: 3 case reports and review of literature

RATIONALE

Renal cell carcinoma associated with Xp11.2 translocations/TFE3 gene fusions is a rare subtype of renal cell carcinoma. This predominantly occurs in juveniles, but rarely seen in adults with lymph node or organic metastasis and a worsened prognosis.

PATIENTS CONCERNS

Herein, we presented 3 adult cases of Xp11-RCC. Two patients were in early stage and good condition, and the third patient had lymph node metastasis but showed no recurrence after a 3-month follow-up.

DIAGNOSES

Case 1: A 50-year-old female without any lumbago and gross hematuria was incidentally detected by left renal mass by ultrasonography. Case 2: A 31-year-old female with 2-year hemodialysis was detected with right renal carcinoma during preoperative examination of renal transplant. Case 3: A 45-year-old male with right lumbago for 1 month was detected with a mass in the lower pole of right kidney by ultrasonography.

INTERVENTION

The characteristics of these 3 images are not consistent with each other, and showed some differences with the previous ones.

OUTCOMES

All these 3 patients underwent laparoscopic radical nephrectomy, and case 1 patient underwent renal hilar lymphnode dissection at the same time. Immunohistochemistry was performed on all the 3 tumors, revealing that the tumor cells were positive for TFE3 and Melan-A. Case 1 showed lymph node metastasis, and received mTOR inhibitors. The 3 patients had no recurrent and new metastasis in other organs after follow-up for 3 months, 2 months, and 11 months, respectively.

LESSONS

Whether the adult-onset Xp-RCC has an aggressive clinical course still remains controversial. Characteristics of the images of the 3 adult cases showed some uniformity but still have some differences. Immunohistochemistry results revealed tumor cell positive for TFE3, but have no consistency in carbonic anhydrase IX, CD117, Ki67, CK8/18 AE1/AE3 and so on. Therefore, the uniform and definitive diagnostic standards of the tumors are uncertain. Hence, more cases and findings are required to elaborate the standards of all the tumor subtypes. Vascular endothelial growth factor-targeted therapy showed some efficacious results in patients with metastasis, but more useful treatments are warranted.

Prognostic and Predictive Factors for Renal Cell Carcinoma

Metastatic renal cell carcinoma (mRCC) is an incurable malignancy, characterized by its resistance to traditional chemotherapy, radiation, and hormonal therapy. Treatment perspectives and prognosis of patients with mRCC have been significantly improved by advances in the understanding of its molecular pathogenesis, which have led to the development of targeted therapeutics. Different molecular factors derived from the tumor or the host detected in both tissue or serum could be predictive of therapeutic benefit. Some of them suggest a rational selection of patients to be treated with certain therapies, though none have been validated for routine use. This article provides an overview of both clinical and molecular factors associated with predictive or prognostic value in mRCC and emphasizes that both should be considered in parallel to provide the most appropriate, individualized treatment and achieve the best outcomes in clinical practice.

Combination of immunohistochemistry, FISH and RT-PCR shows high incidence of Xp11 translocation RCC: comparison of three different diagnostic methods

We evaluated the frequency of translocation renal cell carcinoma (RCC) by reverse transcription polymerase chain reaction (RT-PCR) and how well the TFE3 immunoreactivity is concordant with TFE3 gene translocation status proved by fluorescence in situ hybridization (FISH) assay and RT-PCR. TFE3 and Cathepsin K expression was analyzed by immunohistochemistry in 185 RCC cases, and 48 cases either of more than weak expression of TFE3 or of positivity for Cathepsin K were done for FISH analysis and RT-PCR. All the RT-PCR positive cases were confirmed by cloning and sequencing. Of the 14 cases with strong nuclear TFE3 expression, 12 showed a break-apart signal by FISH. ASPL- and PRCC-TFE3 translocations were detected in 13 and one case, respectively, by RT-PCR. Of 21 cases with weak TFE3 expression, five were translocation-positive by FISH. ASPL-, PRCC-, and PSF-TFE3 translocations were detected by RT-PCR (n=3, 3, and 1, respectively). All 13 TFE3-negative/cathepsin K-positive cases were negative by FISH and two each harbored ASPL- and PRCC-TFE3 translocations that were detected by RT-PCR. A high rate of TFE3 immunoreactivity (8.6%) was confirmed by RT-PCR (13.5%) and FISH (9.7%). Higher translocation rate of RT-PCR means RT-PCR detected translocation in TFE3 weak expression group and only cathepsin K positive group more specifically than FISH. Thus, RT-PCR would complement FISH analysis for detecting translocation RCC with fusion partners.

Xp11.2 translocation renal cell carcinoma with TFE3 gene fusion: A case report

Xp11.2 translocation renal cell carcinoma (RCC) with transcription factor E3 (TFE3) gene fusion is a rare tumor, and the prognosis of this tumor is poorer compared with that of other subtypes of RCC. The patient presented herein was a 70-year-old man who presented with a solid mass sized ~8.2×6.1 cm in the right kidney and underwent radical right nephrectomy. Following pathological and immunohistochemical (IHC) examination and fluorescent in situ hybridization (FISH), the patient was diagnosed with Xp11.2 translocation RCC with TFE3 gene fusion. These tumors are more commonly encountered in children rather than in adults, and adult Xp11.2 translocation RCC is associated with a poorer prognosis compared with its pediatric counterpart. IHC assay and FISH are important diagnostic methods. However, there is currently no established effective treatment for Xp11.2 RCC.

PRCC-TFE3 dual-fusion FISH assay: A new method for identifying PRCC-TFE3 renal cell carcinoma in paraffin-embedded tissue

PRCC-TFE3 renal cell carcinoma (RCC) is one of the most common types of Xp11.2 translocation renal cell carcinoma (tRCC), of which the diagnosis mainly relies on reverse transcription-polymerase chain reaction (RT-PCR) or chromosomal analysis in fresh frozen samples. Herein, we developed a new dual-fusion fluorescence in situ hybridization (FISH) probe to succinctly identify PRCC-TFE3 RCC in paraffin-embedded tissue. We immunohistochemically analyzed TFE3 and cathepsin K expression in 23 cases of Xp11.2 tRCC which had been confirmed by break-apart TFE3 FISH probe. Next, the dual-fusion FISH assay was performed on these selected cases. Twenty typical cases of clear renal cell carcinoma and 20 cases of papillary renal cell carcinoma were collected as control groups. Seven cases were finally confirmed as PRCC-TFE3 RCC by FISH detection, emerging dual-fusion signals, of which 2 cases were identified as PRCC-TFE3 RCC by RT-PCR previously. All remaining cases were negative for the PRCC-TFE3 rearrangement by FISH. The TFE3 immunohistochemistry was positive in 22/23 cases and the cathepsin K was positive in 16/23 cases. All 7 PRCC-TFE3 RCCs showed positive cathepsin K immunoreactivity. Our results reveal that PRCC-TFE3 dual-fusion FISH probe is an efficient and concise technique for diagnosing PRCC-TFE3 RCC in paraffin-embedded tissue.

The MiTF/TFE Family of Transcription Factors: Master Regulators of Organelle Signaling, Metabolism, and Stress Adaptation

The microphthalmia family (MITF, TFEB, TFE3, and TFEC) of transcription factors is emerging as global regulators of cancer cell survival and energy metabolism, both through the promotion of lysosomal genes as well as newly characterized targets, such as oxidative metabolism and the oxidative stress response. In addition, MiT/TFE factors can regulate lysosomal signaling, which includes the mTORC1 and Wnt/β-catenin pathways, which are both substantial contributors to oncogenic signaling. This review describes recent discoveries in MiT/TFE research and how they impact multiple cancer subtypes. Furthermore, the literature relating to TFE-fusion proteins in cancers and the potential mechanisms through which these genomic rearrangements promote tumorigenesis is reviewed. Likewise, the emerging function of the Folliculin (FLCN) tumor suppressor in negatively regulating the MiT/TFE family and how loss of this pathway promotes cancer is examined. Recent reports are also presented that relate to the role of MiT/TFE-driven lysosomal biogenesis in sustaining cancer cell metabolism and signaling in nutrient-limiting conditions. Finally, a discussion is provided on the future directions and unanswered questions in the field. In summary, the research surrounding the MiT/TFE family indicates that these transcription factors are promising therapeutic targets and biomarkers for cancers that thrive in stressful niches. Mol Cancer Res; 15(12); 1637-43. ©2017 AACR.

PD-L1 expression in Xp11.2 translocation renal cell carcinoma: Indicator of tumor aggressiveness

Programmed death ligand-1 (PD-L1), a promising antitumor target, has proven clinical value against many malignancies. However, the PD-L1 content of Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) and its correlation with clinical outcomes remain unclear. This study aimed to investigate PD-L1 expression in Xp11.2 RCC and to assess its prognostic value. Formalin-fixed paraffin-embedded specimens from 36 adult patients that were histologically confirmed (by fluorescence in situ hybridization) were subjected to immunohistochemical analysis. Of the 36 Xp11.2 RCC patients, 9 (25.0%) had tumors with positive PD-L1 expression and 27 (75.0%) had tumors with negative PD-L1 expression. Positive PD-L1 expression correlated with advanced tumor stage (P = 0.001), regional lymph node metastasis (P < 0.001), and distant metastasis (P < 0.001). A multivariate analysis identified positive PD-L1 expression was an independent adverse prognostic factor for both progression free survival (hazard ratio: 3.7, P = 0.018) and overall survival (hazard ratio: 4.5, P = 0.034). The median PFS and OS for the whole cohort were 13.0 months (95% confidence interval [CI], 9.4-16.6 months) and 36.0 months (95% CI, 23.9-48.1 months), respectively. Our findings suggest that positive PD-L1 expression is indicative of worse clinical outcome in Xp11.2 RCC. Further studies are needed to explore the potential efficacy of targeting PD-L1 in Xp11.2 RCC.

[The translocation carcinoma: A pediatric renal tumor also in adults]

The MiT family of translocation-associated renal cell carcinomas comprise approximately 40 % of renal cell carcinomas in young patients but only up to 4 % of renal cell carcinomas in adult patients. The Xp11.2 translocation-associated tumors are the most frequent and were included in the 2004 World Health Organization (WHO) classification. They contain a fusion of the TFE3 gene with ASPSCR1, PRCC, NONO, SPFQ or CLTC resulting in an immunohistochemically detectable nuclear overexpression of TFE3. The Xp11.2 translocation-associated renal cell carcinomas are characterized by ample clear cytoplasm, papillary architecture and abundant psammoma bodies. The TFEB translocation-associated renal cell carcinomas are much rarer and show a biphasic architecture. Fluorescence in situ hybridization permits the detection of a translocation by means of a break apart probe for the TFE3 and TFEB genes and is recommended for the diagnosis of renal cell carcinomas in patients under 30 years of age. The TFE3 and TFEB translocation-associated tumors are classified as MiT family translocation carcinomas in the new WHO classification.The rare renal cell carcinomas harboring an ALK rearrangement with fusion to VCL in young patients with sickle cell trait show a characteristic morphology and are listed in the new WHO classification as a provisional entity.

Renal Cell Carcinoma Associated with Xp11.2 Translocation/TFE3 Gene Fusions: Clinical Features, Treatments and Prognosis

To investigate the clinical characteristics, treatments and prognosis of renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusions (Xp11.2 tRCC), the epidemiological features and treatment results of 34 cases of Xp11.2 tRCC, which were diagnosed by immunohistochemistry staining of TFE3 and fluorescence in situ hybridization at our center, were retrospectively reviewed. The 34 patients included 21 females and 13 males aged 3 to 64 years (median age: 27 years). Four patients were children or adolescents (<18 years of age), and 26 patients were young or middle-aged adults (18–45 years). Radical nephrectomy was performed on 25 patients. Laparoscopic nephron-sparing surgery was performed on 9 patients who presented with an isolated mass with a small diameter (<7 cm) and well-defined boundary on computed tomography imaging. Postoperative staging showed that 25 cases (73.53%) were at stage I/II, while 9 cases (26.47%) were at stage III/IV. All stage I/II patients received a favorable prognosis with a three-year overall survival rate of 100%, including the patients who underwent laparoscopic nephron-sparing surgery. With the exception of 2 children, the other 7 stage III/IV patients died or developed recurrence with a median follow-up of 29 months. On univariate analysis, maximum diameter, adjuvant treatment, TNM stage, lymph node metastasis, inferior vena cava tumor thrombosis and tumor boundary were identified as statistically significant factors impacting survival (P<0.05). Multivariate analysis indicated that TNM stage and inferior vena cava tumor thrombosis were independent prognostic factors (P<0.05). In conclusion, Xp11.2 tRCC is a rare subtype of renal cell carcinoma that mainly occurs in young females. Nephron-sparing surgery was confirmed effective preliminarily in the treatment of small Xp11.2 tRCCs with clear rims. Advanced TNM stage and inferior vena cava tumor thrombosis were associated with poor prognosis.

The proteomic landscape of renal tumors

INTRODUCTION

Renal cell carcinoma (RCC) is the most fatal of the common urologic cancers, with approximately 35% of patients dying within 5 years following diagnosis. Therefore, there is a need for non-invasive markers that are capable of detecting and determining the severity of small renal masses at an early stage in order to tailor treatment and follow-up. Proteomic studies have proved to be very useful in the study of tumors. Areas covered: In this review, we will detail the current knowledge obtained by the different proteomic approaches, focusing on MS-based strategies, used to investigate RCC biology in order to identify diagnostic, prognostic and predictive biomarkers on tissue, cultured cells and biological fluids. Expert commentary: Currently, no reliable biomarkers or targets for RCC have been translated into the clinical setting. Moreover, despite the efforts of proteomics and other -omics disciplines, only a small number of them have been observed as shared targets between the different analytical platforms and biological specimens. The difficulty to define a specific molecular pattern for RCC and its subtypes highlights a peculiar profile and a heterogeneity that must be taken into account in future studies.

Clinical characteristics of XP11.2 translocation/TFE3 gene fusion renal cell carcinoma: a systematic review and meta-analysis of observational studies

Background

Renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusion (Xp11.2 RCC) is a rare subtype of RCC which is firstly described as a distinct entity in 2004 so that clinical characteristics of Xp11.2 RCC in different gender and age are unknown. The purpose of systematic review and meta-analysis is to provide a comprehensive assessment on them.

Methods

MEDLINE, EMBASE and Cochrane databases were searched for studies which evaluate the clinical characteristics of Xp11.2 RCC. The literature published between July 2004 and May 2014 was searched.

Results

A total of 15 studies with 147 participants were included. The meta-analysis demonstrated that number of patients of all age in female was higher than in male with pooled OR of 3.93(95 % CI = 1.66–9.34). However, incidence of distant metastases (OR = 0.34, 95 % CI = 0.12–1.57) and lymphatic metastases (OR = 0.51, 95 % CI = 0.14–1.91), tumor stage (OR = 0.85, 95 % CI = 0.34–2.15) and overall survival (OS) (OR = 0.46, 95 % CI = 0.05–4.34) between male and female were comparable. Incidence in female was higher than in male with pooled OR of 5.13(95 % CI = 1.67–15.72) in adults, while in children no gender-related predominance (OR = 1.19, 95 % CI = 0.38–3.72) was observed. In addition, incidence of distant metastases (OR = 1.00, 95 % CI = 0.13–7.84) and lymphatic metastases (OR = 1.00, 95 % CI = 0.07–13.67) and tumor stage (OR = 1.94, 95 % CI = 0.20–19.03) between children and adults were comparable. Survival curves presented comparable outcomes between male and female (P = 0.707) as well as between children and adults (P = 0.383).

Conclusions

Female patients with Xp11.2 RCC in adults exhibit a high incidence compared to male, but not in children. Comparable clinical characteristics including incidence of distant and lymphatic metastases, tumor stage and prognosis is presented between male and female as well as between children and adults.

Molecular genetics and immunohistochemistry characterization of uncommon and recently described renal cell carcinomas

Renal cell carcinoma (RCC) compromises multiple types and has been emerging dramatically over the recent several decades. Advances and consensus have been achieved targeting common RCCs, such as clear cell carcinoma, papillary RCC and chromophobe RCC. Nevertheless, little is known on the characteristics of several newly-identified RCCs, including clear cell (tubulo) papillary RCC, Xp11 translocation RCC, t(6;11) RCC, succinate dehydrogenase (SDH)-deficient RCC, acquired cystic disease-associated RCC, hereditary leiomyomatosis RCC syndrome-associated RCC, ALK translocation RCC, thyroid-like follicular RCC, tubulocystic RCC and hybrid oncocytic/chromophobe tumors (HOCT). In current review, we will collect available literature of these newly-described RCCs, analyze their clinical pathologic characteristics, discuss their morphologic and immunohistologic features, and finally summarize their molecular and genetic evidences. We expect this review would be beneficial for the understanding of RCCs, and eventually promote clinical management strategies.

Diagnosis of adults Xp11.2 translocation renal cell carcinoma by immunohistochemistry and FISH assays: clinicopathological data from ethnic Chinese population

This study aimed to assess the utility of transcription factor E3 (TFE3) break-apart fluorescence in situ hybridization (FISH) assay in diagnosis of Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) and to compare the clinicopathological features between adult Xp11.2 RCC and non-Xp11.2 RCC. 76 pathologically suspected Xp11.2 RCCs were recruited from our institution. Both TFE3 immunohistochemistry (IHC) and TFE3 FISH assay were performed for the entire cohort. The progression-free survival (PFS) and overall survival (OS) curves were estimated using the Kaplan-Meier method. FISH analysis confirmed 30 Xp11.2 RCCs, including 28 cases with positive TFE3 immunostaining and 2 cases with negative immunostaining. The false-positive and false-negative rates were 6.7% (2/30) and 4.3% (2/46), respectively, for TFE3 IHC compared with FISH assay. Xp11.2 RCC was significantly associated with higher pathological stage and Fuhrman nuclear grade compared with non-Xp11.2 RCC (P < 0.05). The median PFS and OS for TFE3 FISH-positive group were 13.0 months (95% CI, 8.4–17.6 months) and 50.0 months (95% CI, 27.6–72.4 months), respectively, while the median PFS and OS had not been reached for TFE3 FISH-negative group. In conclusion, TFE3 break-apart FISH assay is a highly useful and standard diagnostic method for Xp11.2 RCC. Adult Xp11.2 RCC is clinically aggressive and often presents at advanced stage with poor prognosis.

Dynamic Computed Tomographic Features of Adult Renal Cell Carcinoma Associated With Xp11.2 Translocation/TFE3 Gene Fusions: Comparison With Clear Cell Renal Cell Carcinoma

OBJECTIVE

To investigate the dynamic contrast-enhanced computed tomography (CT) characteristics of renal cell carcinoma associated with Xp11.2 translocation and TFE gene fusion (Xp11.2 RCC) by comparison with clear cell renal cell carcinoma (CCRCC).

METHODS

Dynamic contrast-enhanced CT images and clinical and pathological records of 20 adult patients with Xp11.2 RCC confirmed by TFE3 immunohistochemical and fluorescence in situ hybridization assay were retrospectively analyzed and compared with the findings of 21 contemporary CCRCCs.

RESULTS

Renal cell carcinoma associated with Xp11.2 translocation and TFE gene fusions often occurred in young (30.6 ± 8.6 years) patients with hematuria (9/20). They presented as well-defined (17/20) cystic-solid (17/20) mass with hemorrhage (8/20) and circular/rim calcifications (6/20). Dynamic contrast-enhanced CT showed heterogeneous moderate prolonged enhancement. A tumor-to-cortex attenuation ratio in corticomedullary phase less than 0.62 gave a sensitivity of 90.0% and a specificity of 92.9% in differentiating Xp11.2 RCC from CCRCC (area under the receiver operating characteristic curve = 0.957, P < 0.001).

CONCLUSIONS

Computed tomographic characteristics and dynamic contrast-enhanced patterns and index can differentiate Xp11.2 RCC from CCRCC.

Renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusions: clinical experience and literature review

Aim: To analyze the clinicopathological features of renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusions (Xp11.2 RCC) in our institution. Materials & methods: We screened 983 RCC specimens. TFE3 immunohistochemical staining and FISH assay confirmed 22 Xp11.2 RCCs out of 65 suspicious cases. Clinicopathological and treatment outcomes of 22 patients were retrospectively analyzed. Results: In total, 22 patients included 13 females and nine males with a mean age of 27 years. Ten patients showed gross hematuria. Treatments included surgeries, immunotherapy and molecular-targeted therapy. Seven cases were at stage III/IV and four cases had tumor thrombosis or distant metastasis. During a median follow-up of 34 months, 19 patients were alive while three died of distant metastasis. Conclusion: Xp11.2 RCC is rare and FISH proved a useful diagnostic tool. Surgical resection achieved favorable outcome for early disease. Adult patients at advanced stage had poorer outcomes even with postoperative adjuvant therapy.

Clinicopathological characteristics of Xp11.2 translocation renal cell carcinoma in adolescents and adults: Diagnosis using immunostaining of transcription factor E3 and fluorescence in situ hybridization analysis

OBJECTIVES

To determine the rate and clinicopathological features of Xp11.2 translocation carcinoma using immunostaining of transcription factor E3 and fluorescence in situ hybridization analysis.

METHODS

We evaluated 638 patients with renal cell carcinoma treated at Sapporo Medical University Hospital, Sapporo, Japan, from 1990 to 2009 by reviewing all hematoxylin-eosin-stained sections and carrying out immunostaining of transcription factor E3 for all cases. Fluorescence in situ hybridization analysis was carried out for patients with positive immunostaining or with findings suspicious for Xp11.2 translocation carcinoma on hematoxylin-eosin-stained sections. In this analysis, we set a cut-off level for split signals of at least 10% of nuclei.

RESULTS

Of the 631 patients, 20 (3.2%) were positive for immunostaining. Finally, five patients were diagnosed with Xp11.2 translocation carcinoma (0.8%). Four of these patients were female and aged less than 50 years, and three cases were diagnosed as stage IV with multiple regional lymph nodal or visceral metastases. The positive predictive value of immunostaining was 25%.

CONCLUSION

Patients with Xp11 translocation renal cell carcinoma tend to be younger, more frequently female and diagnosed at a more advanced stage. Immunostaining followed by fluorescence in situ hybridization analysis is an accurate and cost-effective approach for diagnosis of Xp11 translocation renal cell carcinoma.

Dynamic Contrast-Enhanced CT Characterization of Xp11.2 Translocation/TFE3 Gene Fusions versus Papillary Renal Cell Carcinomas

PURPOSE

To compare the differences of CT characteristics between renal cell carcinomas (RCCs) associated with Xp11.2 translocation/TFE3 gene fusions (Xp11.2 RCCs) and papillary cell renal cell carcinomas (PRCCs).

METHODS

CT images and clinical records of 64 patients (25 Xp11.2 RCCs, 15 type 1 and 24 type 2 PRCCs) were analyzed and compared retrospectively.

RESULTS

Xp11.2 RCC more frequently affected young (30.7 ± 8.7 years) women (16/25, 64%) with gross hematuria (12/25, 48%), while PRCC more frequently involved middle-aged (54.8 ± 11.1 years) men (28/39, 71.8%) asymptomatically. Xp11.2 RCC tended to be heterogeneous density with some showing circular calcification. Lesion sizes of Xp11.2 RCC (5.4 ± 2.2 cm) and type 2 PRCC (5.7 ± 2.5 cm) were significantly larger than that of type 1 PRCC (3.8 ± 1.8 cm). Xp11.2 RCC contained more cystic components (22/25, 88%) than type 1 PRCC (all solid) and type 2 PRCC (9/24, 36.0%). Type 1 PRCC (13/15, 86.7%) and Xp11.2 RCC (21/25, 84.0%) showed more clear boundary than type 2 PRCC (12/24, 50.0%).

CONCLUSION

CT features including diameter, boundary, attenuation, nature, and circular calcification of the tumor, combined with demographic information and symptoms, may be useful to differentiate Xp11.2 RCC from different subtypes of PRCC.

Cardiopulmonary bypass-assisted surgery for the treatment of Xp11.2 translocation/TFE3 gene fusion renal cell carcinoma with a tumor thrombus within the inferior vena cava: A case report

Renal cell carcinoma (RCC) accounts for 85-90% of kidney cancers, which in turn account for 2-3% of all malignant tumors in adults. Xp11.2 translocation/TFE3 gene fusion RCC is currently classified as a distinct type of RCC. RCC is capable of invading the renal vein and inferior vena cava to form a tumor thrombus. The incidence of RCC with tumor thrombi within the renal vein or inferior vena cava is 7-10% in China. In the present case report, the patient underwent radical resection of the renal tumor and removal of the tumor thrombus, assisted by cardiopulmonary bypass, for the treatment of Xp11.2 translocation/TFE3 gene fusion RCC. The patient was followed-up for 12 months subsequent to treatment. The patient's renal function remained within the normal range, and computed tomography examination revealed no evidence of disease recurrence or metastases. The present case report aimed to provide a reference for the development of guidelines for the diagnosis and treatment of Xp11.2 translocation/TFE3 gene fusion RCC.

Xp11.2 translocation renal cell carcinomas in young adults

BACKGROUND

Little is known about the biological behavior of Xp11.2 translocation renal cell carcinomas (RCCs) as few clinical studies have been performed using a large sample size.

METHODS

This study included 103 consecutive young adult patients (age ≤ 45 years) with RCC who underwent partial or radical nephrectomy at our institution from 2008 to 2013. Five patients without complete clinical data were excluded. Of the 98 remaining patients, 16 and 82 patients were included in the Xp11.2 translocation and non-Xp11.2 translocation groups, respectively. Clinicopathologic data were collected, including age, gender, tumor size, laterality, symptoms at diagnosis, surgical procedure, pathologic stage, tumor grade, time of recurrence and death.

RESULTS

Xp11.2 translocation RCCs were associated with higher tumor grade and pathologic stage (P < 0.05, Fisher's exact test). During the median follow-up of 36 months (range: 3-71 months), the number of cancer-related deaths was 4 (4.9%) and 3 (18.7%) in the non-Xp11.2 translocation and Xp11.2 translocation groups, respectively. The Kaplan-Meier cancer specific survival curves revealed a significant difference between non-Xp11.2 translocation RCCs and Xp11.2 translocation RCCs in young adults (P = 0.042).

CONCLUSIONS

Compared with non-Xp11.2 translocation RCCs, the Xp11.2 translocation RCCs seemingly showed a higher tumor grade and pathologic stage and have similar recurrence-free survival rates but poorer cancer-specific survival rates in young adults.