The authors present a unique case of small cell variant of clear cell sarcoma of soft parts in a 42-year old woman. The tumor originally arose in the right flank of the soft tissues and ultimately developed both a local recurrence and multiple distant skin metastases two years and ten months thereafter. Nonspecific morphology of small blue round cell tumor was preserved at all microscopically verified sites and initially led to the spectrum of erroneous diagnoses such as an extraskeletal myxoid chondrosarcoma, Ewing sarcoma as well as malignant melanoma. The distinctive features of clear cell sarcoma such as fascicular nested growth pattern, spindling, clear cell change and/or eosinophilic cytoplasm were not disclosed even by extensive sampling. Immunohistochemically, the tumor expressed only S100protein and HMB45; all other markers (CD99, FLI1, cytokeratins, EMA) were completely negative. The molecular analysis carried out in one of the cutaneous metastases revealed translocation t(12;22) (EWSR1-ATF1) and ultimately led to the correct diagnosis of unusual Ewing-like clear cell sarcoma. Discussed is the implementation of molecular tests in routine diagnostics considering the existence of both histologically and biologically different tumors with an identical pathogenic molecular background.

• MeSH
• dospělí MeSH
• fúzní onkogenní proteiny genetika   MeSH
• lidé MeSH
• lokální recidiva nádoru patologie   MeSH
• nádory kůže sekundární   MeSH
• nádory měkkých tkání genetika   patologie   MeSH
• sarkom z jasných buněk genetika   patologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• EWSR1-ATF1 fusion protein, human MeSH Prohlížeč
• fúzní onkogenní proteiny MeSH

Cutaneous tumors with melanocytic differentiation represent a broad group of neoplasms of both melanocytic and non-melanocytic origin. Besides traditional members such as clear-cell sarcoma (CCS) and PEComa, the latter group has recently expanded to also include MITF::CREM fusion-associated tumors, but the available data are limited. Herein, we present a third case of this rare neoplasm which occurred in the temporal region in a 1-year-old girl. It was an infiltratively growing polypoid dermal-based lesion lacking an intraepidermal component. It consisted of cellular solid sheets or small nests of epithelioid to spindled cells with a predominantly eosinophilic and much less commonly clear cytoplasm. The nuclei had round to ovoid shape and exhibited moderate to high-grade atypia and prominent nucleoli. The mitotic activity was 11 mitoses per 10 high-power fields, and atypical mitotic figures were present. Immunohistochemically, the tumor was strongly positive with S100 protein, SOX10, and MITF, while HMB45, tyrosinase, and Melan A were negative. Extensive molecular analysis revealed only MITF::CREM gene fusion. There had no evidence of disease 9 months after the diagnosis. These tumors need to be distinguished from malignant tumors with melanocytic differentiation, primarily from melanoma. However, additional cases still need to be studied to precisely define their biological potential and establish their nosologic status.

• Klíčová slova
• Clear-cell sarcoma-like, Clear-cell tumor, Cutaneous, MITF::CREM fusion, Melanocytic differentiation, Melanoma-like, Skin,
• MeSH
• buněčná diferenciace MeSH
• kojenec MeSH
• lidé MeSH
• melanocyty patologie   MeSH
• melanom * diagnóza   MeSH
• modulátor elementu responzivního pro cyklický AMP metabolismus   MeSH
• nádorové biomarkery analýza   MeSH
• nádory kůže * patologie   MeSH
• sarkom z jasných buněk * genetika   MeSH
• transkripční faktor spojený s mikroftalmií genetika   metabolismus   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• CREM protein, human MeSH Prohlížeč
• MITF protein, human MeSH Prohlížeč
• modulátor elementu responzivního pro cyklický AMP MeSH
• nádorové biomarkery MeSH
• transkripční faktor spojený s mikroftalmií MeSH

Thyroid-like follicular renal cell carcinoma is an uncommon kidney tumor with no distinct molecular alteration described to date. This cohort of eight women with mean and median ages of 45 and 46 years, respectively (range 19-65 years), had unencapsulated, well-circumscribed tumors composed of tightly packed anastomosing follicle-like cysts filled with eosinophilic colloid-like material and lined by cuboidal cells with high nuclear to cytoplasmic ratios, oval to elongated nuclei with perpendicular arrangement toward the lumens, and prominent nuclear overlapping. The stroma between these was minimal with the exception of two tumors. Calcifications and necrosis were absent. Immunohistochemically, the tumors were positive for KRT19 (7/7), PAX8 (5/5), cyclin D1 (6/6), KRT7 (5/7), and AMACR (1/5; focal, weak), and were negative for WT1, TTF1 (transcription termination factor-1), and thyroglobulin. In three of three tumors tested molecularly, EWSR1-PATZ1 fusion was identified by RNA sequencing and confirmed by RT-PCR and Sanger sequencing. Over a follow-up period of 1-7 years, no evidence of recurrence or metastasis has been detected. The EWSR1-PATZ1 fusion has been recognized as a recurrent alteration in a subset of round to spindle cell sarcomas with EWSR1-non-ETS fusions (EWSR1-PATZ1 sarcoma) and in several central nervous system tumors. The finding of an EWSR1-PATZ1 fusion in all three of the thyroid-like follicular renal cell carcinomas for which sufficient tissue was available for genomic profiling provides the first distinct molecular abnormality in thyroid-like follicular renal cell carcinomas, supporting its designation as a distinct diagnostic entity.

• MeSH
• dospělí MeSH
• karcinom z renálních buněk genetika   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• nádory ledvin genetika   patologie   MeSH
• onkogenní fúze * MeSH
• protein EWS vázající RNA genetika   MeSH
• represorové proteiny genetika   MeSH
• senioři MeSH
• transkripční faktory Krüppel-like genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• PATZ1 protein, human MeSH Prohlížeč
• protein EWS vázající RNA MeSH
• represorové proteiny MeSH
• transkripční faktory Krüppel-like MeSH

Perivascular epithelioid cell tumour (PEComa) is a rare mesenchymal tumour made up of clear perivascular cells with epithelioid characteristics, which co-expresses muscle and melanocytic markers with a component of spindle cells, like sarcoma and variety of other tissues. This time, we present the case of a young patient with a tumour in the dorsal region of progressive growth, compatible with PEComa of soft tissue after histopathological and immunohistochemical analysis.

• Klíčová slova
• Case reports, Perivascular epithelioid cell neoplasms, Rare diseases, Sarcoma, Soft tissue neoplasms,
• MeSH
• lidé MeSH
• nádory z perivaskulárních epiteloidních buněk * diagnóza   chirurgie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Kidney tumours form a broad spectrum of distinguished histopathological and molecular genetic entities. The last WHO classification is dated to 2004. Current classification has been published in October 2013 by ISUP (International Society of Urological Pathology). There were 5 new epithelials tumours: tubulocystic renal cell carcinoma (RCC), acquired cystic disease-associated RCC, clear cell (tubulo-)papillary RCC, the MiT family translocation RCCs (in particular t(6;11) RCC), and hereditary leiomyomatosis RCC syndrome-associated RCC. Another 3 subtypes of RCC were added as "provisional" entities: thyroid-like follicular RCC; succinate dehydrogenase B deficiency-associated RCC; and ALK translocation RCC. Modifications were performed in already existing entities: multicystic clear cell RCC (formerly multilocular cystic RCC) is newly included as a subcategory of clear cell RCC with low malignant potential. Oncocytic papillary RCC (PRCC) has not been recognized as a distinctive subcategory of PRCC yet. Hybrid oncocytic-chromophobe tumour was placed within the chromophobe RCC category. Recent advances related to collecting duct carcinoma, renal medullary carcinoma, and mucinous spindle cell and tubular RCC were elucidated. Outside of the epithelial category, current approach to our understanding of angiomyolipoma, including the epithelioid variant and angiomyolipoma with epithelial cysts was clarified. Cystic nephroma and mixed epithelial and stromal tumour were considered as a spectrum of one entity. Synovial sarcoma was placed within the sarcoma group. The new classification is to be referred to as the International Society of Urological Pathology Vancouver Classification of Renal Neoplasia.

• MeSH
• karcinom z renálních buněk * klasifikace   diagnóza   patologie   MeSH
• ledviny patologie   MeSH
• lidé MeSH
• nádory ledvin * klasifikace   diagnóza   patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND/AIM: Spontaneous regression (SR) of tumours is a rare phenomenon not yet fully understood. The aim of this study was to investigate immune cells infiltrating progressive and SR tumours in a Lewis rat sarcoma model. MATERIALS AND METHODS: Rats were subcutaneously inoculated with rat sarcoma R5-28 (clone C4) cells. Developing tumours were obtained on day 42 and cryosections were immunohistochemically processed for detection of immune cells. RESULTS: A high density of granulocytes was found in the necrotic areas of both progressive and SR tumours. CD4+ cells and CD8+ cells were rare and sparsely dispersed in the tumour tissue without clear difference between the two types of tumours. On the contrary, CD161+ cells were abundant and evenly distributed in SR tumours, but these cells were very rare in progressive tumours. CONCLUSION: Based on the differences in number and distribution of the immune cell subpopulations, we believe that natural killer (CD161+) cells play a major role in the destruction of cancer cells during SR of tumours in this Lewis rat model.

• Klíčová slova
• CD161, CD4, CD8, Tumour, immunohistochemistry, spontaneous regression,
• MeSH
• buňky NK patologie   MeSH
• CD4-pozitivní T-lymfocyty patologie   MeSH
• CD8-pozitivní T-lymfocyty patologie   MeSH
• imunohistochemie MeSH
• krysa rodu Rattus MeSH
• lektinové receptory NK-buněk - podrodina B genetika   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• potkani inbrední LEW MeSH
• regulace genové exprese u nádorů MeSH
• sarkom genetika   patologie   MeSH
• spontánní regrese nádoru genetika   patologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• lektinové receptory NK-buněk - podrodina B MeSH

The epithelioid variant of angiomyolipoma (EAML) is a rare tumor of unpredictable behavior that is composed of epithelioid, spindle, and giant cells and contains no or only a minimal amount of lipomatous tissue. The picture can lead to an erroneous diagnosis of renal cell carcinoma or sarcoma. We report on a case of EAML in the kidney of a 47-year-old female without any signs of tuberous sclerosis and review the literature. Grossly, a well-demarcated, spheroid, largely hemorrhagic tumor measuring 4.2 cm in diameter occupied the central third of the kidney. Histologically, it was solid, highly cellular, with occasional microcysts, composed of medium to large epithelioid cells with clear or oxyphilic cytoplasm, short spindle cells, and numerous giant multinucleated cells. After extensive sampling, adult-appearing fat tissue was found to present as rare foci of microscopic dimensions. Immunohistochemically, the tumor cells showed positive reactions with antibodies against HMB-45, melan A, CD-68, muscle-specific actin, and, rarely, smooth muscle actin. Cytokeratins and epithelial membrane antigen were negative. The EAML is a variant growing in a carcinoma-like pattern that can lead to an erroneous diagnosis of renal cell carcinoma. An extensive sampling and HMB-45 and CD-68 positivity combined with cytokeratin negativity are of paramount importance for the correct diagnosis. As a sporadic renal tumor it followed a benign course in most of the reported cases.

• MeSH
• aktiny analýza   MeSH
• angiomyolipom chemie   patologie   chirurgie   MeSH
• antigeny diferenciační myelomonocytární analýza   MeSH
• antigeny nádorové MeSH
• CD antigeny analýza   MeSH
• diferenciální diagnóza MeSH
• epiteloidní buňky chemie   patologie   MeSH
• karcinom z renálních buněk chemie   diagnóza   MeSH
• lidé středního věku MeSH
• lidé MeSH
• MART-1 antigen MeSH
• melanomové antigeny MeSH
• nádorové biomarkery analýza   MeSH
• nádorové proteiny analýza   MeSH
• nádory ledvin chemie   patologie   chirurgie   MeSH
• obrovské buňky patologie   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• aktiny MeSH
• antigeny diferenciační myelomonocytární MeSH
• antigeny nádorové MeSH
• CD antigeny MeSH
• CD68 antigen, human MeSH Prohlížeč
• MART-1 antigen MeSH
• melanomové antigeny MeSH
• MLANA protein, human MeSH Prohlížeč
• nádorové biomarkery MeSH
• nádorové proteiny MeSH

35-year-old woman suffered prolonged pain in the left shoulder, where an aggressively growing tumor of the proximal humerus was revealed thereafter. The lesion caused massive osteolysis of the metaepiphysis with cortical disruption, but no soft tissue extension was evident. Given the unsatisfactory effect, the ongoing neoadjuvant chemotherapy was prematurely ceased and the resection 13 cm long segment of bone with modular prosthesis replacement followed. Histologically, clear-cut malignant tumor with both the presence of numerous reactive osteoclast-like giant cells and geographic structural deposition of chondroid matrix bore a close resemblance to chondroblastoma. Dominant cellular composition formed solid mosaic clusters of large, atypical, frequently binucleated cells with voluminous eosinophilic cytoplasm. Impressive nuclear pleomorphism was accentuated by both the grooving and atypical mitotic figures. Thorough sampling disclosed limited, but sharply contrasting parts, where biphasic arrangement of small uniform stromal elements together with regularly distributed, reactive osteoclasts suggested putative precursor giant cell lesion. Except the osteoclasts, all matrical and stromal cells were strongly SOX9 and D2-40 positive; in contrary desmin, SATB2, S100 and p63 yielded completely negative results. Detected H3F3A c.103G>T mutation in exon 2 finally established true nature of that peculiar neoplastic proliferation and lead to descriptive term of primary chondroblastoma-like malignant giant cell tumor. In the setting of all the microscopic variability, histogenesis and complex differential diagnosis of skeletal (malignant) giant cell lesions, there are discussed e.g. aggressive/malignant chondroblastoma, chondroblastoma-like osteosarcoma or giant cell-rich osteosarcoma and practical impact of specific mutational analysis results as well.

• Klíčová slova
• H3F3A mutation, chondroblastoma, chondroblastoma-like, humerus, primary malignant giant cell tumor of the bone,
• MeSH
• chondroblastom * komplikace   diagnóza   chirurgie   MeSH
• dospělí MeSH
• humerus MeSH
• lidé MeSH
• nádory kostí * komplikace   diagnóza   chirurgie   MeSH
• nádory obrovskobuněčné * komplikace   diagnóza   chirurgie   MeSH
• osteosarkom * komplikace   diagnóza   chirurgie   MeSH
• transkripční faktory MeSH
• vazebné proteiny DNA v oblastech připojení k matrix * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• SATB2 protein, human MeSH Prohlížeč
• transkripční faktory MeSH
• vazebné proteiny DNA v oblastech připojení k matrix * MeSH

The classification working group of the International Society of Urological Pathology consensus conference on renal neoplasia was in charge of making recommendations regarding additions and changes to the current World Health Organization Classification of Renal Tumors (2004). Members of the group performed an exhaustive literature review, assessed the results of the preconference survey and participated in the consensus conference discussion and polling activities. On the basis of the above inputs, there was consensus that 5 entities should be recognized as new distinct epithelial tumors within the classification system: tubulocystic renal cell carcinoma (RCC), acquired cystic disease-associated RCC, clear cell (tubulo) papillary RCC, the MiT family translocation RCCs (in particular t(6;11) RCC), and hereditary leiomyomatosis RCC syndrome-associated RCC. In addition, there are 3 rare carcinomas that were considered as emerging or provisional new entities: thyroid-like follicular RCC; succinate dehydrogenase B deficiency-associated RCC; and ALK translocation RCC. Further reports of these entities are required to better understand the nature and behavior of these highly unusual tumors. There were a number of new concepts and suggested modifications to the existing World Health Organization 2004 categories. Within the clear cell RCC group, it was agreed upon that multicystic clear cell RCC is best considered as a neoplasm of low malignant potential. There was agreement that subtyping of papillary RCC is of value and that the oncocytic variant of papillary RCC should not be considered as a distinct entity. The hybrid oncocytic chromophobe tumor, which is an indolent tumor that occurs in 3 settings, namely Birt-Hogg-Dubé Syndrome, renal oncocytosis, and as a sporadic neoplasm, was placed, for the time being, within the chromophobe RCC category. Recent advances related to collecting duct carcinoma, renal medullary carcinoma, and mucinous spindle cell and tubular RCC were elucidated. Outside of the epithelial category, advances in our understanding of angiomyolipoma, including the epithelioid and epithelial cystic variants, were considered. In addition, the apparent relationship between cystic nephroma and mixed epithelial and stromal tumor was discussed, with the consensus that these tumors form a spectrum of neoplasia. Finally, it was thought that the synovial sarcoma should be removed from the mixed epithelial and mesenchymal category and placed within the sarcoma group. The new classification is to be referred to as the International Society of Urological Pathology Vancouver Classification of Renal Neoplasia.

• MeSH
• lidé MeSH
• nádory ledvin klasifikace   MeSH
• společnosti lékařské MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• konsensus - konference MeSH

: The authors present 2 cases of a subcutaneous biphasic synovial sarcoma with marked apocrine differentiation that potentially may be confused with cutaneous epithelial neoplasms, including malignant apocrine mixed tumor or metaplastic carcinoma with an apocrine glandular component. Microscopically, both neoplasms had a biphasic architecture with the epithelial and spindle cell components. The epithelial component was prominent and consisted of simple glands with round lumina and complex glandular structures with intraluminal bridges forming cribriform areas. The glands were lined by cuboidal to columnar cells with eosinophilic or clear cytoplasm manifesting apical apocrine-like and intraluminal eosinophilic secretions. The spindle cell component was less prominent and was composed of relatively uniform or slightly atypical spindle sells surrounding and merging focally with the glandular structures. Immunohistochemically, the tumor cells in both components were positive for vimentin, AE1/AE3, CK7, and epithelial membrane antigen. Desmin, smooth muscle actin, muscle-specific actin, CD34, and S-100 protein were all negative. SYT-SSX1 gene fusion using fluorescence in situ hybridization and RT-PCR methods was detected in both cases.

• MeSH
• apokrinní žlázy patologie   MeSH
• buněčná diferenciace MeSH
• fúzní onkogenní proteiny genetika   MeSH
• hybridizace in situ fluorescenční MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádorové biomarkery analýza   MeSH
• nádory měkkých tkání genetika   patologie   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• synoviom genetika   patologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• fúzní onkogenní proteiny MeSH
• nádorové biomarkery MeSH
• SYT-SSX fusion protein MeSH Prohlížeč