Classification of renal cell tumors – current concepts and use of ancillary tests: recommendations of the Brazilian Society of Pathology

Rare renaissance: Quadruple synchronous renal cell tumors in one kidney - A case report

Multifocality in renal tumors is a rare occurrence, but not unheard of. Commonly the different foci correspond to the same histological pathology, however co-existence with other renal lesions, including both malignant and benign tumors, have also been reported. Here we present a 57-year-old male, ex-smoker who exhibited four distinct histological tumors in an ipsilateral kidney; multilocular cystic clear cell renal cell carcinoma (RCC) of low malignant potential, clear cell papillary RCC, renal oncocytoma, and renomedullary interstitial cell tumor. To our knowledge this is the first time these four tumors were found in the same patient, let alone the same kidney.

Case Report: Optimum excision with split skin graft closure in the management of penile sebaceous carcinoma

Sebaceous carcinoma (SC) is a rare malignant skin neoplasm derived from the meibomian gland of adnexal epithelium, which is frequently confused with basal cell carcinoma (BCC), exhibiting sebaceous differentiation and commonly found in the head and neck regions. We report a case of penile sebaceous carcinoma, an extremely rare anatomical site for SC. A 68-year-old man presented with a 4-month history of painless, non-healing ulcerated nodules over the left side of the penile shaft. Wedge biopsy showed adenocarcinoma with signet ring differentiation. We proceeded with wide local excision (WLE) of the lesion with the inclusion of the indurated skin and 5 mm of normal margin, followed by primary closure of the scrotal defect and split skin grafting of the penile shaft by using a thigh skin donor. The final histopathological examination revealed sebaceous carcinoma with pagetoid spread. The patient achieved recurrence-free survival without any form of adjuvant therapy after 4 years of follow-up.

Prediction of Distant Metastases in Patients with Kidney Cancer Based on Gene Expression and Methylation Analysis

Clear cell renal cell carcinoma (ccRCC) is the most common and aggressive histological type of cancer in this location. Distant metastases are present in approximately 30% of patients at the time of first examination. Therefore, the ability to predict the occurrence of metastases in patients at early stages of the disease is an urgent task aimed at personalized treatment. Samples of tumor and paired histologically normal kidney tissue from patients with metastatic and non-metastatic ccRCC were studied. Gene expression was analyzed using real-time PCR. The level of gene methylation was evaluated using bisulfite conversion followed by quantitative methylation-specific PCR. Two groups of genes were analyzed in this study. The first group includes genes whose expression is significantly reduced during metastasis: CA9, NDUFA4L2, EGLN3, and BHLHE41 (p < 0.001, ROC analysis). The second group includes microRNA genes: MIR125B-1, MIR137, MIR375, MIR193A, and MIR34B/C, whose increased methylation levels are associated with the development of distant metastases (p = 0.002 to <0.001, ROC analysis). Based on the data obtained, a combined panel of genes was formed to identify patients whose tumors have a high metastatic potential. The panel can estimate the probability of metastasis with an accuracy of up to 92%.

Renal Cell Carcinoma in End-Stage Renal Disease: A Retrospective Study in Patients from Hungary

INTRODUCTION

End-stage renal disease (ESRD) and acquired cystic kidney disease (ACKD) are known risk factors for renal cell carcinoma (RCC). Hereby, the clinicopathological features of RCCs developed in ESRD were investigated.

METHODS

A database consisting of 34 tumors from 31 patients with ESRD among 2,566 nephrectomy samples of RCC was built. The demographic, clinical, and follow-up data along with pathological parameters were analyzed. The RCCs were diagnosed according to the current WHO Classification of Urinary and Male Genital Tumors.

RESULTS

Twenty-two tumors developed in men and 12 in women, with a median age of 56 years (range: 27-75 years). The causes of ESRD were glomerulonephritis (n = 7), hypertensive kidney disease (n = 6), autosomal dominant polycystic kidney disease (n = 6), chronic pyelonephritis (n = 4), diabetic nephropathy (n = 3), chemotherapy-induced nephropathy (n = 1), and undetermined (n = 4). ACKD complicated ESRD in 12 patients. The following histological subtypes were identified: clear cell RCC (n = 19), papillary RCC (n = 5), clear cell papillary tumor (n = 5), ACKD RCC (n = 3), and eosinophilic solid and cystic RCC (n = 2). The median tumor size was 31 mm (range: 10-80 mm), and 32 tumors were confined to the kidney (pT1-pT2). There was no tumor-specific death during the period of this study. Progression was registered in 1 patient.

CONCLUSION

In our cohort, the most common RCC subtype was clear cell RCC (55%), with a frequency that exceeded international data appreciably (14-25%). The incidence of clear cell papillary tumor and ACKD RCC (14.7% and 8.5%) was lower than data reported in the literature (30% and 40%). Our results indicate a favorable prognosis of RCC in ESRD.

Cardiotoxicity of Selected Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitors in Patients with Renal Cell Carcinoma

Renal cell carcinoma (RCC) is one of the most frequent malignant neoplasms of the kidney. The therapeutic options available for the treatment of advanced or metastatic RCC include vascular endothelial growth factor receptor (VEGFR)-targeted molecules, for example, tyrosine kinase inhibitors (TKI). Various VEGFR-TKIs proved to be effective in the treatment of patients with solid tumours. The combination of two drugs may prove most beneficial in the treatment of metastatic RCC; however, it also enhances the risk of toxicity compared to monotherapy. Specific VEGFR-TKIs (e.g., sunitinib, sorafenib or pazopanib) may increase the rate of cardiotoxicity in metastatic settings. VEGF inhibitors modulate multiple signalling pathways; thus, the identification of the mechanism underlying cardiotoxicity appears challenging. VEGF signalling is vital for the maintenance of cardiomyocyte homeostasis and cardiac function; therefore, its inhibition can be responsible for the reported adverse effects. Disturbed growth factor signalling pathways may be associated with endothelial dysfunction, impaired revascularization, the development of dilated cardiomyopathy, cardiac hypertrophies and altered peripheral vascular load. Patients at high cardiovascular risk at baseline could benefit from clinical follow-up in the first 2-4 weeks after the introduction of targeted molecular therapy; however, there is no consensus concerning the surveillance strategy.

Are Renal Cell Carcinoma with Fibromyomatous Stroma (RCC-FMS) and Thyroid-like Follicular Carcinoma of the Kidney (TLFCK) Really Independent Variants?

BACKGROUND

Renal cell carcinoma with fibromyomatous stroma (RCC-FMS) is a recent provisional entity already recognised in the 2016 WHO Classification of Cancer of the Urinary Tract and Male Genital Organs 4th Edition as renal cell carcinoma with (angio)leiomyomatous stroma, histologically defined as a tumour characterised by clear cells intertwined in a conspicuous vascular stroma. In the casuistry taken into consideration, another proposed variant, thyroid-like follicular carcinoma of the kidney (TLFCK), endowed with a morphology mimicking thyroid parenchyma, was examined. The aim of this work was to parse the theoretical system, experimental data and diagnostic impact of these new entities proposed in the field of renal neoplasms.

MATERIALS AND METHODS

An analysis of 120 cases of kidney tumours from the Department of Surgical, Medical, Molecular and Critical Area at the University of Pisa was run. Subsequently, all samples were reassessed by two pathologists with expertise in uropathology, whose revaluation provided a histomorphological study combined with subsequent and coherent immunohistochemical analyses of CK7, CD10, CAIX, CK34betaE12, CD117, vimentin, TTF-1 and thyroglobulin. These analyses were performed using the Ventana Benchmark Automated Staining System (Ventana Medical Systems, Tucson, AZ, USA) and Ventana reagents.

RESULTS

On the one hand, the data, thus brought to light, did not show an immunohistochemical profile consistent with that proposed for RCC-FMS. However, it should be emphasised that the morphological background also unearthed a poor specificity for RCC-FMS. This was specifically due to a stromal component which was, in any case, evident, although characterised by a wide range of presentation, in clear cell renal cell carcinoma (ccRCC). This latter is, indeed, the reference background for this theorised variant. On the other hand, a thyroid-like pattern was highlighted in 11 cases, more specifically in 10 ccRCCs and in one oncocytoma, presenting itself as a type of neoplastic appearance rather than as the peculiar morphological pattern of a standalone cancer.

CONCLUSIONS

In the light of these results, RCC-FMS and TLFCK appear to be more appropriately variants of already categorised neoplastic entities rather than new independent neoplasias.

Contemporary Clinical Definitions, Differential Diagnosis, and Novel Predictive Tools for Renal Cell Carcinoma

Despite significant progress regarding clinical detection/imaging evaluation modalities and genetic/molecular characterization of pathogenesis, advanced renal cell carcinoma (RCC) remains an incurable disease and overall RCC mortality has been steadily rising for decades. Concomitantly, clinical definitions have been greatly nuanced and refined. RCCs are currently viewed as a heterogeneous series of cancers, with the same anatomical origin, but fundamentally different metabolisms and clinical behaviors. Thus, RCC pathological diagnosis/subtyping guidelines have become increasingly intricate and cumbersome, routinely requiring ancillary studies, mainly immunohistochemistry. Meanwhile, RCC-associated-antigen targeted systemic therapy has been greatly diversified and emerging, novel clinical applications for RCC immunotherapy have already reported significant survival benefits, at least in the adjuvant setting. Even so, systemically disseminated RCCs still associate very poor clinical outcomes, with currently available therapeutic modalities only being able to prolong survival. In lack of a definitive cure for advanced RCCs, integration of the amounting scientific knowledge regarding RCC pathogenesis into RCC clinical management has been paramount for improving patient outcomes. The current review aims to offer an integrative perspective regarding contemporary RCC clinical definitions, proper RCC clinical work-up at initial diagnosis (semiology and multimodal imaging), RCC pathological evaluation, differential diagnosis/subtyping protocols, and novel clinical tools for RCC screening, risk stratification and therapeutic response prediction.

Renal cell carcinoma with atypical metastases sites revealed by diabetes mellitus: A case report

INTRODUCTION AND IMPORTANCE

Lung, bone, lymph nodes and liver are the most common metastatic sites. This observation presents a metastatic renal cell carcinoma (RCC) with atypical secondary sites and a rare mode of revelation corresponding to diabetes mellitus.

CASE PRESENTATION

We report the case of a 64-year-old woman recently diagnosed with diabetes mellitus. A thoracic parietal nodule was palpated. An uro-CT scan had shown a renal tumor with unusual metastatic sites: pleura, pancreas, and contralateral kidney. The patient underwent a biopsy of the pleural nodule. The pathology report concluded to the diagnosis of clear cell RCC. She had a targeted therapy. Three months after admission, the patient had altered general condition and total hematuria.

CLINICAL DISCUSSION

RCC commonly metastasizes haematogenously via renal veins. Atypically, secondary lesions may involve pleura. Such a metastatic site may be of particular interest for percutaneous biopsy, as in our case. The rare metastatic invasion of the pancreas is most likely the cause of the inaugural diabetes in our patient. The controlateral kidney was involved in 1.4% of secondary lesions. For patients with poor prognosis, according to International Metastatic RCC Database Consortium classification, anti-angiogenic treatment is recommended. The median overall survival of patients with poor prognosis is 8 months.

CONCLUSIONS

Pancreas and contralateral kidney are rare secondary sites of RCC. The clinical expression of pancreas metastatic invasion can rarely fit with diabetes. Metastatic dissemination to these organs is most often associated with an unfavorable prognosis.

Macrophage Phenotype in Combination with Tumor Microbiome Composition Predicts RCC Patients’ Survival: A Pilot Study

The identification of new prognostic markers of renal cell carcinoma (RCC) is an urgent problem in oncourology. To investigate the potential prognostic significance of tumor microbiome and stromal inflammatory markers, we studied a cohort of 66 patients with RCC (23 clear cell RCC, 19 papillary RCC and 24 chromophobe RCC). The microbiome was analyzed in tumor and normal tissue by 16S rRNA amplicon sequencing. Characterization of the tumor stroma was performed using immunohistochemistry. A significant difference in alpha diversity was demonstrated between normal kidney tissue and all types of RCC. Further, we demonstrated that the bacterial burden was higher in adjacent normal tissue than in a tumor. For the first time, we demonstrated a significant correlation between bacterial burden and the content of PU.1+ macrophages and CD66b+ neutrophils in kidney tumors. Tumors with high content of PU.1+ cells and CD66b+ cells in the stroma were characterized by a lower bacterial burden. In the tumors with high bacterial burden, the number of PU.1+ cells and CD66b+ was associated with a poor prognosis. The identified associations indicate the great prognostic potential of a combined tumor microbiome and stromal cell analysis.

Precision Medicine: An Optimal Approach to Patient Care in Renal Cell Carcinoma

Renal cell cancer (RCC) is a heterogeneous tumor that shows both intra- and inter-heterogeneity. Heterogeneity is displayed not only in different patients but also among RCC cells in the same tumor, which makes treatment difficult because of varying degrees of responses generated in RCC heterogeneous tumor cells even with targeted treatment. In that context, precision medicine (PM), in terms of individualized treatment catered for a specific patient or groups of patients, can shift the paradigm of treatment in the clinical management of RCC. Recent progress in the biochemical, molecular, and histological characteristics of RCC has thrown light on many deregulated pathways involved in the pathogenesis of RCC. As PM-based therapies are rapidly evolving and few are already in current clinical practice in oncology, one can expect that PM will expand its way toward the robust treatment of patients with RCC. This article provides a comprehensive background on recent strategies and breakthroughs of PM in oncology and provides an overview of the potential applicability of PM in RCC. The article also highlights the drawbacks of PM and provides a holistic approach that goes beyond the involvement of clinicians and encompasses appropriate legislative and administrative care imparted by the healthcare system and insurance providers. It is anticipated that combined efforts from all sectors involved will make PM accessible to RCC and other patients with cancer, making a tremendous positive leap on individualized treatment strategies. This will subsequently enhance the quality of life of patients.

Circular RNA Eps15-homology domain-containing protein 2 induce resistance of renal cell carcinoma to sunitinib via microRNA-4731-5p/ABCF2 axis

Circular RNAs (circRNAs) are linked with the occurrence and progression of renal cell carcinoma (RCC). However, circRNAs’ mechanism in developing resistance to RCC has not been clarified. This research assessed the role and mechanism of circular RNA circ Eps15-homology domain-containing protein 2 (EHD2) in the resistance of sunitinib (SU) to RCC. ACHN, 786-O, 769P, and HEK-293 T cells and RCC tissue samples were used for the investigations. The circEHD2 expression in RCC cells and tissues was determined through RT-qPCR. Association of circEHD2 with RCC histological grade of RCC was done through Chi-square. MiR-4731-5p, ABCF2, and circEHD2 were transfected into RCC cell lines. A dual-luciferase reporter assay was used to determine the interaction between miR-4731-5p, circEHD2, and ABCF2. MTT assay was used to analyze cell viability, while apoptosis was studied using flow cytometry. Colony-formation and transwell experiments were used to assess migration and invasion. The ATP Binding Cassette Subfamily F Member 2 (ABCF2) expression was analyzed through western blot. The results showed increased circEHD2 in SU-resistant RCC tissues and cell lines and implicated in RCC histological grade and SU resistance. Knock-down of circEHD2 down-regulated the resistance of RCC to SU in vitro and vivo; circEHD2 bound to miR-4731-5p to mediate ABCF2 in RCC; ABCF2 rescued the inhibitory effect of circEHD2 knock-down on SU resistance of RCC. In conclusion, circEHD2 enhances RCC resistance to SU via acting as a miR-4731-5p sponge to mediate ABCF2. MiR-4731-5p can target circEHD2 and ABCF2, thus providing a novel and effective therapeutic against renal cell carcinoma.

lncRNA PVT1 in the Pathogenesis and Clinical Management of Renal Cell Carcinoma

LncRNA PVT1 (plasmacytoma variant translocation 1) has become a staple of the lncRNA profile in patients with renal cell carcinoma (RCC). Common dysregulation in renal tumors outlines the essential role of PVT1 in the development of RCC. There is already a plethora of publications trying to uncover the cellular mechanisms of PVT1-mediated regulation and its potential exploitation in management of RCC. In this review, we summarize the literature focused on PVT1 in RCC and aim to synthesize the current knowledge on its role in the cells of the kidney. Further, we provide an overview of the lncRNA profiling studies that have identified a more or less significant association of PVT1 with the clinical behavior of RCC. Based on our search, we analyzed the 17 scientific papers discussed in this review that provide robust support for the indispensable role of PVT1 in RCC development and future personalized therapy.