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Histopathologically, oral squamous cell carcinoma (OSCC) consists of well-defined interfaces with adjacent non-cancerous epithelium. Previously, we found that SCC tissues expressed higher levels of specific proteins at this interface. Ladinin-1 (LAD1) is one of the specific molecules that has increased expressions in cancer fronts; however, its function in OSCC is unknown. Therefore, this study aimed to elucidate the function of LAD1 in human OSCC cells. LAD1 was localized on the actin arc at the distal periphery of cell clusters in the OSCC cell lines HSC-2, HSC-3, and HSC-4. When LAD1 was knocked down, cellular migration was repressed in wound scratch assays but was reversed in three-dimensional collagen gel invasion assays. Characteristic LAD1 localization along actin arcs forming the leading edge of migrating cells was diminished with loss of filopodia formation and ruffling in knockdown cells, in which the expression levels of cell motility-related genes-p21-activated kinase 1 (PAK1) and caveolin-1 (CAV1)-were upregulated and downregulated, respectively. LAD1 expression was also associated with the downregulation of vimentin and increased histological differentiation of OSCC. These results suggest that LAD1 is involved in actin dynamics during filopodia and lamellipodia formation, and in maintaining the epithelial phenotype of OSCC cells.
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Actinas , Carcinoma de Células Escamosas , Movimiento Celular , Neoplasias de la Boca , Humanos , Actinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/genética , Caveolina 1/metabolismo , Caveolina 1/genética , Línea Celular Tumoral , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/genética , Quinasas p21 Activadas/metabolismo , Quinasas p21 Activadas/genética , Fenotipo , Vimentina/metabolismo , Vimentina/genéticaRESUMEN
BACKGROUND: Large non-apoptotic vesicles released from the plasma membrane protrusions are classified as large-EVs (LEVs). However, the triggers of LEV secretion and their functions in tumors remain unknown. METHODS: Coculture system of cancer cells, peritoneal mesothelial cells (PMCs), and macrophages (MΦs) was conducted to observe cell-cell contact-mediated LEV secretion. Lineage tracing of PMCs was performed using Wt1CreERT2-tdTnu mice to explore the effects of LEVs on PMCs in vivo, and lymphangiogenesis was assessed by qRT-PCR and flow-cytometry. RESULTS: In peritoneal dissemination, cancer cells expressing Ephrin-B (EFNB) secreted LEVs upon the contact with PMCs expressing ephrin type-B (EphB) receptors, which degraded mesothelial barrier by augmenting mesothelial-mesenchymal transition. LEVs were incorporated in subpleural MΦs, and these MΦs transdifferentiated into lymphatic endothelial cells (LEC) and integrated into the lymphatic vessels. LEC differentiation was also induced in PMCs by interacting with LEV-treated MΦs, which promoted lymphangiogenesis. Mechanistically, activation of RhoA-ROCK pathway through EFNB reverse signaling induced LEV secretion. EFNBs on LEVs activated EphB forward signaling in PMC and MΦs, activating Akt, ERK and TGF-ß1 pathway, which were indispensable for causing MMT and LEC differentiation. LEVs accelerated peritoneal dissemination and lymphatic invasions by cancer cells. Blocking of EFNBs on LEVs using EphB-Fc-fusion protein attenuated these events. CONCLUSIONS: EFNBhigh cancer cells scattered LEVs when they attached to PMCs, which augmented the local reactions of PMC and MΦ (MMT and lymphangiogenesis) and exaggerated peritoneal dissemination.
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Comunicación Celular , Vesículas Extracelulares , Linfangiogénesis , Animales , Ratones , Vesículas Extracelulares/metabolismo , Humanos , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/metabolismo , Neoplasias Peritoneales/patología , Neoplasias Peritoneales/genética , Macrófagos/metabolismo , Macrófagos/patología , Peritoneo/patología , Peritoneo/metabolismo , Línea Celular Tumoral , Técnicas de Cocultivo , Transducción de SeñalRESUMEN
Rectal implantation cysts can occur at anastomotic sites after low anterior resection (LAR) for rectal cancer. Herein, we report a case of primary adenocarcinoma arising from a rectal implantation cyst after LAR for rectal cancer. A 70-year-old woman was referred to our hospital for diagnosis and treatment of a growing cystic lesion. She had LAR performed for rectal cancer 29 years previously and had a rectal implantation cyst detected 13 years previously. On the first visit to our hospital, serum CEA and CA19-9 levels were elevated, and computed tomography (CT) scans revealed a cystic lesion near the anastomosis. CT-guided biopsy revealed no cancer tissue in the cystic lesion. After that, the cystic lesion naturally shrank, and serum CEA and CA19-9 levels became normal. Follow-up included 3 monthly serum CEA and CA19-9 testing and 6 monthly CT scans. Two years later, serum CEA and CA19-9 levels were elevated again. Colonoscopy revealed an ulcerative lesion at the anastomotic site, in which adenocarcinoma was confirmed. Abdominoperineal resection with sacral resection was performed, and postoperative histopathological examination revealed a primary adenocarcinoma with mucinous component at the implantation cyst. Since rectal implantation cysts can become malignant after extended periods, clinicians need to be aware of this disease.
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Adenocarcinoma , Quistes , Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Femenino , Anciano , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Adenocarcinoma/diagnóstico , Quistes/cirugía , Quistes/etiología , Quistes/patología , Quistes/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Complicaciones Posoperatorias/etiología , Antígeno Carcinoembrionario/sangre , Proctectomía , Enfermedades del Recto/cirugía , Enfermedades del Recto/etiología , Enfermedades del Recto/patología , Anastomosis Quirúrgica , Antígeno CA-19-9/sangreRESUMEN
Diabetic neuropathy (DN) is a major complication of diabetes mellitus. Chondroitin sulfate (CS) is one of the most important extracellular matrix components and is known to interact with various diffusible factors; however, its role in DN pathology has not been examined. Therefore, we generated CSGalNAc-T1 knockout (T1KO) mice, in which CS levels were reduced. We demonstrated that diabetic T1KO mice were much more resistant to DN than diabetic wild-type (WT) mice. We also found that interactions between pericytes and vascular endothelial cells were more stable in T1KO mice. Among the RNA-seq results, we focused on the transforming growth factor ß signaling pathway and found that the phosphorylation of Smad2/3 was less upregulated in T1KO mice than in WT mice under hyperglycemic conditions. Taken together, a reduction in CS level attenuates DN progression, indicating that CS is an important factor in DN pathogenesis.
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Colorectal cancer (CRC) is a heterogeneous disease that develops through stepwise accumulation of genetic alterations and progresses via several distinct pathways. However, the tumorigenesis of CRCs with BRAF non-V600E mutations remains unclear. Here, we aimed to elucidate the tumorigenesis of CRCs with BRAF non-V600E mutations, focusing on differences in mucin phenotype and genetic alterations between CRCs with non-V600E and V600E mutations. We investigated 201 patients with CRC and performed panel testing of 415 genes to identify BRAF mutations. Patients were classified into five mucin phenotypes - large-intestinal, small-intestinal, gastric, mixed, and unclassified - using immunohistochemistry for CD10, MUC2, MUC5AC, and MUC6. BRAF mutations were identified in 24 of 201 patients' samples, of which 13 (6.5%) had a V600E mutation (V600E-mutant) and 11 (5.5%) had non-V600E mutations (non-V600E-mutant). MUC5AC expression was significantly associated with V600E mutations (P = 0.040), while CD10 expression was significantly associated with non-V600E mutations (P = 0.010). The small-intestinal mucin phenotype was significantly associated with non-V600E mutations (P = 0.031), while the mixed mucin phenotype was significantly associated with V600E mutations (P = 0.027). Regarding genetic alterations, focusing on the WNT signaling pathway, APC mutation was significantly associated with non-V600E mutations (P < 0.001), while RNF43 mutation was significantly associated with V600E mutations (P = 0.020). Considering the differences in mucin phenotype and genetic alterations, different modes of tumorigenesis are assumed for CRC with BRAF V600E mutation and non-V600E mutations. These findings are important in understanding the biology and treatment strategies for BRAF-mutant CRC.
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Neoplasias Colorrectales , Proteínas Proto-Oncogénicas B-raf , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Carcinogénesis , Transformación Celular Neoplásica , Mutación , Fenotipo , Neoplasias Colorrectales/genéticaRESUMEN
BACKGROUND AND AIMS: Decompensated cirrhosis with fibrosis progression causes portal hypertension followed by an oedematous intestinal tract. These conditions weaken the barrier function against bacteria in the intestinal tract, a condition called leaky gut, resulting in invasion by bacteria and bacterial components. Here, we investigated the role of outer-membrane vesicles (OMVs) of Escherichia coli, which is the representative pathogenic gut-derived bacteria in patients with cirrhosis in the pathogenesis of cirrhosis. METHODS: We investigated the involvement of OMVs in humans using human serum and ascites samples and also investigated the involvement of OMVs from E. coli in mice using mouse liver-derived cells and a mouse cirrhosis model. RESULTS: In vitro, OMVs induced inflammatory responses to macrophages and neutrophils, including the upregulation of C-type lectin domain family 4 member E (Clec4e), and induced the suppression of albumin production in hepatocytes but had a relatively little direct effect on hepatic stellate cells. In a mouse cirrhosis model, administration of OMVs led to increased liver inflammation, especially affecting the activation of macrophages, worsening fibrosis and decreasing albumin production. Albumin administration weakened these inflammatory changes. In addition, multiple antibodies against bacterial components were increased with a progressing Child-Pugh grade, and OMVs were detected in ascites of patients with decompensated cirrhosis. CONCLUSIONS: In conclusion, OMVs induce inflammation, fibrosis and suppression of albumin production, affecting the pathogenesis of cirrhosis. We believe that our study paves the way for the future prevention and treatment of cirrhosis.
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Ascitis , Escherichia coli , Humanos , Ratones , Animales , Cirrosis Hepática , InflamaciónRESUMEN
Hepatic small vessel neoplasia (HSVN) is a recently recognized hemangioma of the liver with uncertain malignant potential. Almost all the patients are asymptomatic. Budd-Chiari syndrome (BCS) is a rare disorder characterized by noncardiogenic hepatic venous outflow obstruction. Benign hepatocellular nodules have been acknowledged for a long time in the liver with the chronic BCS. However, there has been no case report of BCS associated with HSVN. The patient was diagnosed with BCS 13 years ago. The imaging test initially displayed multiple hepatic nodules that were suspected of benign hepatocellular nodules. They gradually increased in size and number in the course of the disease. At an autopsy, these nodules were confirmed to be multifocal HSVN. The tumor of the present case could not be proved to have GNAQ and GNQ14 mutations. We describe the case focusing on the chronological imaging changes and discuss on the relationship between BCS and HSVN.
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Síndrome de Budd-Chiari , Carcinoma Hepatocelular , Hemangioma , Neoplasias Hepáticas , Humanos , Síndrome de Budd-Chiari/patología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patologíaRESUMEN
Artificial nucleic acids have attracted much attention as potential cancer immunotherapeutic materials because they are recognized by a variety of extracellular and intracellular nucleic acid sensors and can stimulate innate immune responses. However, their low selectivity for cancer cells causes severe systemic immunotoxicity, making it difficult to use artificial nucleic acid molecules for immune cancer therapy. To address this challenge, we herein introduce a hairpin DNA assembly technology that enables cancer-selective immune activation to induce cytotoxicity. The designed artificial DNA hairpins assemble into long nicked double-stranded DNA triggered by intracellular microRNA-21 (miR-21), which is overexpressed in various types of cancer cells. We found that the products from the hairpin DNA assembly selectively kill miR-21-abundant cancer cells in vitro and in vivo based on innate immune activation. Our approach is the first to allow selective oncolysis derived from intracellular DNA self-assembly, providing a powerful therapeutic modality to treat cancer.
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Antineoplásicos , Técnicas Biosensibles , MicroARNs , Ácidos Nucleicos , MicroARNs/genética , ADN , Inmunidad InnataRESUMEN
Renal cell carcinoma (RCC) is a heterogeneous disease comprising a variety of histological subtypes. Approximately 70-80% of RCC cases are clear cell carcinoma (ccRCC), while the remaining subtypes constitute non-clear cell carcinoma (nccRCC). The medical treatment of RCC has greatly changed in recent years through advances in molecularly targeted therapies and immunotherapies. Most of the novel systemic therapies currently available have been approved based on ccRCC clinical trial data. nccRCC can be subdivided into more than 40 histological subtypes that have distinct clinical, histomorphological, immunohistochemical, and molecular features. These entities are listed as emerging in the 2022 World Health Organization classification. The diagnosis of nccRCC and treatments based on cancer histology and biology remain challenging due to the disease's rarity. We reviewed clinical trials focused on recent discoveries regarding clinicopathological features.
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We herein report a 45-year-old-man with multiple foreign body granulomas in the lungs caused by polytetrafluoroethylene (PTFE). A mass in the right lower lobe of the lung and bilateral centrilobular lung nodules were found unexpectedly during the patient's visit to a hospital for a respiratory infection. The patient's occupation for 26 years involved spraying PTFE. A lung biopsy using bronchoscopy revealed granulomatous lesions and giant cells. The presence of fluorine in the granulomatous lesions was confirmed using an electron probe microanalyzer with wavelength dispersive spectrometer. Fluorine is a component of PTFE and is not found in normal lung tissue.
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Enfermedades Pulmonares , Enfermedades Profesionales , Humanos , Persona de Mediana Edad , Politetrafluoroetileno/efectos adversos , Flúor , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/patología , Enfermedades Profesionales/complicaciones , Pulmón/diagnóstico por imagen , Pulmón/patología , Granuloma/patologíaRESUMEN
The 5th edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems contains relevant revisions and introduces a group of molecularly defined renal tumour subtypes. Herein we present the World Health Organization (WHO) 2022 perspectives on papillary and chromophobe renal cell carcinoma with emphasis on their evolving classification, differential diagnosis, and emerging entities. The WHO 2022 classification eliminated the type 1/2 papillary renal cell carcinoma (pRCC) subcategorization, given the recognition of frequent mixed tumour phenotypes and the existence of entities with a different molecular background within the type 2 pRCC category. Additionally, emerging entities such as biphasic squamoid alveolar RCC, biphasic hyalinising psammomatous RCC, papillary renal neoplasm with reverse polarity, and Warthin-like pRCC are included as part of the pRCC spectrum, while additional morphological and molecular data are being gathered. In addition to oncocytomas and chromophobe renal cell carcinoma (chRCC), a category of 'other oncocytic tumours' with oncocytoma/chRCC-like features has been introduced, including emerging entities, most with TSC/mTOR pathway alterations (eosinophilic vacuolated tumour and so-called 'low-grade' oncocytic tumour), deserving additional research. Eosinophilic solid and cystic RCC was accepted as a new and independent tumour entity. Finally, a highly reproducible and clinically relevant universal grading system for chRCC is still missing and is another niche of ongoing investigation. This review discusses these developments and highlights emerging morphological and molecular data relevant for the classification of renal cell carcinoma.
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Adenoma Oxifílico , Carcinoma de Células Renales , Neoplasias Renales , Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/patología , Diagnóstico Diferencial , Humanos , Riñón/patología , Neoplasias Renales/patología , Masculino , Organización Mundial de la SaludRESUMEN
The three-tier immunophenotype (desert, excluded, and inflamed) and the four-tier immunophenotype (cold, immunosuppressed, excluded, and hot) have been linked to prognosis and immunotherapy response. This study aims to evaluate whether immunophenotypes of clear cell renal cell carcinoma, identified on hematoxylin and eosin-stained slides, correlate with gene expression signatures related to cancer immunity, and clinical outcomes. We evaluated tumor-associated immune cells (TAICs) status using three methodologies: three-tier immunophenotype based on the location of TAICs, four-tier immunophenotype considering both the location and degree of TAICs and inflammation score focusing only on the degree of TAICs, using a localized clear cell renal cell carcinoma cohort (n = 436) and The Cancer Genome Atlas (TCGA)-KIRC cohort (n = 162). We evaluated the association of the TAICs status assessed by three methodologies with CD8 and PD-L1 immunohistochemistry and immune gene expression signatures by TCGA RNA-sequencing data. All three methodologies correlated with immunohistochemical and immune gene expression signatures. The inflammation score and the four-tier immunophenotype showed similarly higher accuracy in predicting recurrence-free survival and overall survival compared to the three-tier immunophenotype. In conclusion, a simple histologic assessment of TIACs may predict clinical outcomes and immunotherapy responses.
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A number of recently described renal tumor entities share an eosinophilic/oncocytic morphology, somewhat solid architectural growth pattern, and tendency to present as low-stage tumors. The vast majority of such tumors follow a non-aggressive clinical behavior. In this review, we discuss the morphological, immunohistochemical, and molecular genetic profiles of the three most recent novel/emerging renal entities associated with TSC/mTOR pathway mutations. These are eosinophilic solid and cystic renal cell carcinoma, eosinophilic vacuolated tumors, and low-grade oncocytic tumors, which belong to a heterogeneous group of renal tumors, demonstrating mostly solid architecture, eosinophilic/oncocytic cytoplasm, and overlapping morphological and immunohistochemical features between renal oncocytoma and chromophobe renal cell carcinoma. All three tumors also share a molecular genetic background with mutations in the mTORC1 pathway (TSC1/TSC2/mTOR/RHEB). Despite the common genetic background, it appears that the tumors with TSC/mTOR mutations represent a diverse group of distinct renal neoplasms.
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BACKGROUND Gastric carcinoma (GC) remains one of the most common and deadly neoplasms in the world. Liposarcoma (LPS) is the most common sarcoma of adults. However, synchronous or metachronous occurrence of GC with LPS seems to be very rare. Tumor staging and differential diagnosis with these cases are extremely difficult. CASE REPORT The patient was a man in his 70s, who reported anorexia and weight loss of 4 kg over 2 months. Gastroscopy demonstrated a large tumor of Borrmann type 3, of which histology was moderately to poorly differentiated adenocarcinoma. The clinical stage was initially defined as IVb due to a 11×6 cm retroperitoneal (RP) tumor. Despite chemotherapy for GC, the RP tumor rapidly enlarged. Endoscopic ultrasound-guided fine-needle aspiration biopsy showed that it was an undifferentiated sarcoma. He died of hepatorenal failure secondary to severe jaundice. The autopsy revealed a synchronous occurrence of GC and RP sarcoma. GC had no areas admixed with sarcoma. Histology of RP sarcoma showed that it mainly consisted of undifferentiated sarcoma and focally of well-differentiated LPS characterized by well-differentiated adipocytes admixed with scattered atypical stromal cells. The tumor cells in both areas were positive for MDM2 and CDK4 by immunohistochemistry. The diagnosis of the RP sarcoma was revised to dedifferentiated LPS. CONCLUSIONS There were no previous case reports of synchronous occurrence of GC with LPS in the English and Japanese literature. GC and LPS pose challenging problems in their diagnoses, staging, and treatments when they occur synchronously or metachronously.
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Carcinoma , Liposarcoma , Neoplasias Retroperitoneales , Neoplasias Gástricas/diagnóstico , Anciano , Carcinoma/diagnóstico , Humanos , Inmunohistoquímica , Liposarcoma/diagnóstico , Masculino , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Retroperitoneales/diagnósticoRESUMEN
The prognostic significance of an architectural grading system for clear cell renal cell carcinoma (ccRCC) has recently been demonstrated. The present study aimed to establish a vascularity-based architectural classification using the cohort of 436 patients with localized ccRCC who underwent extirpative surgery and correlated the findings with conventional pathologic factors, gene expression, and prognosis. First, we assessed architectural patterns in the highest-grade area on hematoxylin and eosin-stained slides, then separately evaluated our surrogate score for vascularity. We grouped nine architectural patterns into three categories based on the vascular network score. "Vascularity-based architectural classification" was defined: category 1: characterized by enrichment of the vascular network, including compact/small nested, macrocyst/microcystic, and tubular/acinar patterns; category 2: characterized by a widely spaced-out vascular network, including alveolar/large nested, thick trabecular/insular, papillary/pseudopapillary patterns; category 3: characterized by scattered vascularity without a vascular network, including solid sheets, rhabdoid and sarcomatoid patterns. Adverse pathological prognostic factors such as TNM stage, WHO/ISUP grade, and necrosis were significantly associated with category 3, followed by category 2 (all p < 0.001). We successfully validated the classification using The Cancer Genome Atlas (TCGA) cohort (n = 162), and RNA-sequencing data available from TCGA showed that the angiogenesis gene signature was significantly enriched in category 1 compared to categories 2 and 3, whereas the immune gene signature was significantly enriched in category 3 compared to categories 1 and 2. In univariate analysis, vascularity-based architectural classification showed the best accuracy in pathological prognostic factors for predicting recurrence-free survival (c-index = 0.786). The predictive accuracy of our model which integrated WHO/ISUP grade, necrosis, TNM stage, and vascularity-based architectural classification was greater than conventional risk models (c-index = 0.871 vs. 0.755-0.843). Our findings suggest that the vascularity-based architectural classification is prognostically useful and may help stratify patients appropriately for management based on their likelihood of post-surgical recurrence.
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Carcinoma de Células Renales , Neoplasias Renales , Carcinoma de Células Renales/patología , Expresión Génica , Humanos , Neoplasias Renales/patología , Necrosis , PronósticoRESUMEN
The suppressors of cytokine signaling (SOCS) proteins are negative regulators of cytokine signaling required to prevent excessive cellular responses. In particular, SOCS3 is involved in the regulation of metabolic syndromes, such as obesity and diabetes, by suppressing leptin and insulin signals. SOCS3 also suppresses the inflammatory response associated with metabolic stress, but this specific role remains undefined. Wild-type mice on a high-fat diet (HFD) exhibited only fatty liver, whereas systemic deletion of SOCS3 resulted in excessive myeloid hematopoiesis and hepatic inflammation. In addition, depletion of the gut microbiota resulted in considerable improvement in excess granulopoiesis and splenomegaly, halting the progression of systemic inflammation in SOCS3KO mice on the HFD. This result suggests that intestinal dysbiosis is involved in inflammation associated with SOCS3KO. Although contributing to diet-induced obesity and fatty liver, SOCS3 is nevertheless critical to suppress excess myeloid hematopoiesis and severe systemic inflammation associated with intestinal dysbiosis on HFD.
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Renal cell carcinoma (RCC) represents a heterogeneous disease, encompassing an increasing number of tumor subtypes. Post-2016, the World Health Organization (WHO) classification recognized that the spectrum of papillary renal cell carcinoma is evolving and has long surpassed the dichotomic simplistic "type 1 versus type 2" classification. The differential diagnosis of pRCC includes several new provisional/emerging entities with papillary growth. Type 2 tumors have been cleared out of several confounding entities, now regarded as independent tumors with specific clinical and molecular backgrounds. In this work we describe the prevalence and characteristics of emerging papillary tumor entities in two renal tumor cohorts (one consisting of consecutive papillary tumors from a single institute, the other consisting of consultation cases from several centers). After a review of 154 consecutive pRCC cases, 58% remained type 1 pRCC, and 34% type 2 pRCC. Papillary renal neoplasm with reversed polarity (1.3%), biphasic hyalinizing psammomatous RCC (1.3%), and biphasic squamoid/alveolar RCC (4.5%) were rare. Among 281 consultation cases, 121 (43%) tumors had a dominant papillary growth (most frequently MiT family translocation RCCs, mucinous tubular and spindle cell carcinoma and clear cell papillary RCC). Our data confirm that the spectrum of RCCs with papillary growth represents a major diagnostical challenge, frequently requiring a second expert opinion. Papillary renal neoplasm with reversed polarity, biphasic hyalinizing psammomatous RCC, and biphasic squamoid/alveolar RCC are rarely sent out for a second opinion, but correct classification and knowledge of these variants will improve our understanding of the clinical behavior of renal tumors with papillary growth.
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Following the publication of this paper, the Journal was alerted by an investigation committee of Niigata University to the fact that the paper had been identified as a duplicate publication, which had already been published. Therefore, in accordance with the rules of Niigata University Fraud Investigation committee, a request was made that the paper be retracted. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in International Journal of Oncology 38: 1227-1236, 2011; DOI: 10.3892/ijo.2011.959].