RESUMEN
Synovial sarcoma (SS) and solitary fibrous tumor (SFT) are entities with considerable morphological and immunohistochemical similarities that sometimes show a non-confirmatory profile (TLE1 negative, CD34 and focal or negative STAT6 and lack of specific fusion IHC markers), in which the utility ultrastructure is unknown. A cross-sectional, retrospective, analytical, nonexperimental study was carried out by the Department of Pathology of the National Cancer Institute of Mexico (INCan) e from January 1, 2009 to December 31, 2018. With 17 SFT cases with diffuse or focal CD34 and STAT6 positivity and 18 cases of SS with positive FISH molecular test t(X:18) breakapart were studied by electron microscopy of fresh glutaraldehyde fixed or paraffin-embedded tissue. The ultrastructural findings with a significant difference present in the SS were tandem tight junctions, desmosomes and abundance of dilated rough endoplasmic reticulum (RER) cisternae (p < 0.001, 0.003, and 0.001, respectively); while in the (SFT) the presence of abundant glycogen, basal lamina, long and slender cytoplasmic processes, pinocytic vesicles, hemidesmosomes, and/or dense plaques, collagen skein, and microvilli-like buds (p = 0.028, 0.005, and <0.001 for the last five). We then infer that the five distinctive markers of the SFT are the collagen skeins intermingled with cellular processes in a shape of "squid can," and the pinocytic vesicles as they were not observed in any case of SS. Conversely, tandem junctions were not found in any SFT case. Although the presence of multivesicular buds in the SFT was not significant, it had not been previously described.
Asunto(s)
Sarcoma Sinovial , Tumores Fibrosos Solitarios , Humanos , Tumores Fibrosos Solitarios/patología , Tumores Fibrosos Solitarios/ultraestructura , Sarcoma Sinovial/ultraestructura , Sarcoma Sinovial/patología , Adulto , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , México , Estudios Transversales , Biomarcadores de Tumor , Anciano , Adulto Joven , Diagnóstico DiferencialRESUMEN
PURPOSE: Salivary gland tumors are rare and include benign and malignant entities with different behavior and prognosis. Salivary gland carcinoma accounts for 0.2% of all cancers and 5-9% of head and neck carcinomas. We aim to describe the clinicopathological characteristics and discuss the immunohistochemical findings of salivary ductal carcinoma. METHODS: We obtained 17 cases (2.3%) of salivary ductal carcinoma (SDC) from 727 patients with parotid tumors at our cancer center from a database covering a 22-year period (1996-2018). Two pathologists confirmed the diagnosis and excluded 6 cases. Eleven cases were assessed by immunohistochemistry (IHC) for HER2, estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), mammaglobin, P53, GATA3, S100, cytokeratins (7,8,14,18, and 20), P63, PAX8, calponin, and SOX10. RESULTS: Eleven SDC cases were in advanced stage, and 80% had metastasis. All cases were surgically treated, and 40% received different adjuvant chemotherapy regimens. we found that most patients were dead of disease. The histological and immunohistochemical analysis showed that 70% of cases were high-grade, 40% were positive for HER2, and 50% for AR. Moreover, a high Ki-67 proliferative index was detected in all cases. We observed luminal differentiation in 50% of cases. CONCLUSION: SDC is a rare entity and survival is very poor. It is histologically similar to ductal carcinoma of the breast. However, important differences exist that help to distinguish them in case of synchronous cancers. The clinical behavior of SDC seems to be more aggressive and IHC analysis is useful for designing therapies.
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Carcinoma Ductal , Aparato Lagrimal , Neoplasias de la Parótida , Neoplasias de las Glándulas Salivales , Biomarcadores de Tumor , Carcinoma Ductal/terapia , Humanos , InmunohistoquímicaRESUMEN
OBJECTIVE: To immunohistochemically characterize a group of oral myofibroblastic lesions (MLs) and to evaluate the ultrastructural features of myofibroblasts. MATERIAL AND METHODS: Using a tissue microarray technique (TMA), cases of myofibroma (MF), of nodular fasciitis (NF), of desmoplastic fibroma (DF), and of myofibroblastic sarcoma (MS) from the Universidad Autónoma Metropolitana Xochimilco, and a Private Oral Pathology Service in Mexico City were stained with antibodies against alpha-smooth muscle actin (α-SMA), H-caldesmon, vimentin, desmin, ß-catenin, CD34, anaplastic lymphoma protein kinase (ALK-1), and Ki-67. RESULTS: Nineteen of the 22 MF cases, 2/5 of the NF cases, 1/10 of the DF cases, and 1/2 of the MS cases were positive for α-SMA. 1/2 of the MS cases were positive for desmin; 6/10 of the DF cases were positive for ß-catenin, and 2 of the MF cases were positive for ALK-1. All of the MLs were positive for vimentin and negative for H-caldesmon and CD-34. The Ki-67 labeling index in all of the 8/22 MF, 3/5 NF, and 2/2 MS cases was ≥10%. For all of the MLs evaluated, ultrastructural analysis revealed spindle-shaped cells containing endoplasmic reticulum and peripheral actin filament bundles. CONCLUSION: In certain myofibroblastic lesions, the use of auxiliary techniques (such as immunohistochemistry) can be critical for differential diagnosis.
Asunto(s)
Fibroma/diagnóstico , Fibroma/patología , Boca/patología , Miofibroblastos/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Inmunohistoquímica , Lactante , Masculino , México , Persona de Mediana Edad , Miofibroblastos/ultraestructura , Análisis de Matrices Tisulares , Adulto JovenRESUMEN
Ependymoma is a rare central nervous system neoplasm with an even rarer morphologic variant called giant-cell ependymoma (GCE). GCE has a characteristic discrepant, malignant-like morphology but indolent behavior. We present the case of a 21-year-old female with an extra-axial GCE located in the sacral region. To date, 16 cases of sacral GCE have been reported in the literature, with 4 cases in the sacral region; however, all those cases were intra-axial. We present the first case of an extra-axial sacral GCE.
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Ependimoma/patología , Neoplasias de los Tejidos Blandos/patología , Femenino , Humanos , Región Sacrococcígea , Adulto JovenRESUMEN
Ovarian mature cystic teratoma (OMCT) is an ovarian benign neoplasm with excellent prognosis presenting components of the three germinal layers. However, transformation into a malignant neoplasm is a rare event (so-called somatic transformation). In most of the cases, the malignant component expresses as epidermoid carcinoma, but occasionally central nervous system tumors occur. Some of the previously reported tumors are astrocytoma, glioblastoma, and ependymoma. Somatic transformation of OMCT into an oligodendroglioma is exceptional. We report a 19-year-old female with a left OMCT with an area of oligonedroglial cells proliferation characterized by immunohistochemical studies with positivity for GFAP and S100, with a low Ki67 index (5%). Additionally, electron microscopy revealed oligodendrocytes with parallel bundles of cytoplasmic intermediate filaments, confirming the oligodendroglial nature of the proliferation. The patient was treated only with left oophorectomy, and three and half years after surgery, there is no evidence of disease.
Asunto(s)
Biomarcadores de Tumor/análisis , Proliferación Celular , Inmunohistoquímica , Microscopía Electrónica , Neoplasias Quísticas, Mucinosas y Serosas/diagnóstico , Oligodendroglioma/diagnóstico , Neoplasias Ováricas/diagnóstico , Teratoma/diagnóstico , Femenino , Humanos , Neoplasias Quísticas, Mucinosas y Serosas/química , Neoplasias Quísticas, Mucinosas y Serosas/cirugía , Neoplasias Quísticas, Mucinosas y Serosas/ultraestructura , Oligodendroglioma/química , Oligodendroglioma/cirugía , Oligodendroglioma/ultraestructura , Neoplasias Ováricas/química , Neoplasias Ováricas/cirugía , Neoplasias Ováricas/ultraestructura , Ovariectomía , Valor Predictivo de las Pruebas , Salpingectomía , Teratoma/química , Teratoma/cirugía , Teratoma/ultraestructura , Resultado del Tratamiento , Adulto JovenRESUMEN
The diagnosis of malignant pleural mesothelioma (MPM) is challenging and requires immunohistochemistry or electron microscopy assays to specifically differentiate MPM from lung adenocarcinoma. An ultrastructural study of fresh tissue is considered to be the "gold standard." In most cases, the first diagnostic approach is performed on pleural effusion, and in some patients, this is the only available sample for diagnosis. The aim of the present study is to evaluate if an examination of pleural effusion samples based on electron microscopy (EMpe) is a useful tool for the differential diagnosis of MPM and lung adenocarcinoma. An EMpe study was performed in 25 pleural effusion samples. Histological and immunohistochemical markers confirmed the diagnosis of either mesothelioma (5) or adenocarcinoma (20). Of the five cases that were diagnosed with mesothelioma, two samples (40%) showed cells with "bushy" microvilli, which are characteristic of mesothelioma, by EMpe, and three were acellular (60%). Of the 20 cases of adenocarcinoma, EMpe showed cells with short microvilli in 9 (45%), and 11 were acellular (55%). EMpe identifies unequivocal morphological changes that are useful for the differential diagnosis of MPM or adenocarcinoma when the pleural effusion sample contains evaluable tumor cells.
Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias Pulmonares/diagnóstico , Mesotelioma/diagnóstico , Derrame Pleural Maligno/patología , Neoplasias Pleurales/diagnóstico , Adenocarcinoma/ultraestructura , Adenocarcinoma del Pulmón , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Citodiagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/ultraestructura , Masculino , Mesotelioma/ultraestructura , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Neoplasias Pleurales/ultraestructuraRESUMEN
BACKGROUND: Recent reviews have referred to the paranuclear dot-like staining pattern of CD99 in several neoplasms, including solid pseudopapillary tumors in the pancreas, colonic adenocarcinomas, and colonic adenomas as well as in Merkel cell carcinoma (MCC). The aim of this work was to explore the utility of CD99 paranuclear staining in the differential diagnosis of MCC. MATERIAL AND METHODS: We explore paranuclear dot-like CD99 expression in several small, round blue cell neoplasms, including neuroendocrine neoplasms, Ewing sarcomas/primitive neuroectodermal tumors (EWS/PNET), melanomas, small cell lung carcinomas (SCC), lymphoblastic lymphoma/leukemia, and rhabdomyosarcomas, in comparison with 33 cases of MCC, to determine the specificity of the paranuclear dot-like CD99 expression in MCC. RESULTS: Twenty MCC (60%) demonstrated focal expression of CD99 and of those, 14 (42.4%) showed the characteristic paranuclear dot-like expression. CD99 was also paranuclear positive in 4 of 11 (36%) SCC, in 3 of 7 (43%) EWS/PNET, in 1 of 6 (16%) lymphoblastic lymphoma/leukemia cases, in 3 of 3 (100%) rhabdomyosarcomas and all melanomas were negative for the CD99 reaction. CONCLUSION: CD99 paranuclear dot-like expression was not exclusive of the MCC compared with several neoplasms included in its differential diagnosis. This expression is not a great diagnostic aid.
Asunto(s)
Antígeno 12E7/biosíntesis , Biomarcadores de Tumor/análisis , Carcinoma de Células de Merkel/diagnóstico , Diagnóstico Diferencial , Neoplasias Cutáneas/diagnóstico , Antígeno 12E7/análisis , Carcinoma de Células de Merkel/metabolismo , Humanos , Inmunohistoquímica , Neoplasias Cutáneas/metabolismoRESUMEN
The Clinco-pathological, immunohistochemical and molecular findings of four cases of Mammary Analogue Secretory Carcinoma (MASC) of salivary glands found in Mexico are described. The cases were extracted from 253 salivary gland tumors from a single institution in Mexico City. The 85 Candidates for initial selection were: low grade mucoepidermoid carcinoma (MEC) (N=70 ), Acinic cell cancinoma (AciCC) (N=14), papillary cystadenocarcinoma (N=1), and adenocarcinoma NOS (N=0). Tumors with some histological features consistent with MASC (N= 17, 6.7%) were studied by immunohistochemistry for mammaglobin, STAT5, and S-100 protein and four cases were positive (1.5%), thus the diagnosis of MASC was established, and these were submitted for molecular studies for ETV6-NTRK3. Fusion gene was demonstrated in three cases, two had been erroneously diagnosed as poorly granulated AciCC, and one as low grade MEC with microcystic pattern. Female gender predominated (3:1); one occurred in the parotid, two in minor salivary glands and one in the submaxillary gland; infiltrating borders, atypical mitosis and lymph node metastases were seen in the parotideal tumor. Two patients with major salivary gland tumors are alive and well at 10 and 20 months respectively, the two patients with minor salivary gland tumors are lost. It can be concluded that is important to think in MASC in poorly granulated AciCC and low grade MEC with microcystic pattern. Immunohistochemisty studies confirm the diagnosis, preferentially supported by molecular studies. MASC may follow aggressive behavior or transform into a high grade neoplasm.
Asunto(s)
Carcinoma Secretor Análogo al Mamario/patología , Neoplasias de las Glándulas Salivales/patología , Adulto , Anciano de 80 o más Años , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Mexican specialists in oncology, oncologic surgery, thoracic surgery, pneumology, pathology, molecular biology, anesthesiology, algology, psychology, nutrition, and rehabilitation (all of them experts in lung cancer treatment) in order to develop the National Consensus on Lung Cancer. The consensus has been developed as an answer to the need of updated Mexican guidelines for the optimal treatment of the disease, as well as to the requirements that such guidelines be established by multidisciplinary panel, depicting the current attention given to cancer lung cases in Mexico. Thus, this paper analyses the epidemiological review, screening, diagnosis, staging, pathology, translational medicine, and the suitable therapies for early, locally advanced, and metastatic disease in the first, second, and third lines of management, as well as rehabilitation and palliative measures.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Algoritmos , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Carcinoma de Pulmón de Células no Pequeñas/etiología , Carcinoma de Pulmón de Células no Pequeñas/secundario , Árboles de Decisión , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/etiología , México , Estadificación de Neoplasias , Fumar/efectos adversosRESUMEN
Pleuropulmonary synovial sarcoma (PPSS) is a rare entity, similar to synovial sarcoma of soft tissue (STSS). There are 120 published cases of PPSS, but no studies have explored the expression of TLE1. In soft tissues, it has been proven a useful marker, but in tumors of other sites, its expression has not been explored. The main objective was to study the expression and diagnostic sensitivity and specificity of TLE1 in a group of PPSS, of which the diagnosis was corroborated by fluorescence in situ hybridization confirming t(X;18) in a tissue microarray. Immunohistochemistry including TLE1, vimentin, CD99, CD56, bcl-2, AE1-AE3, EMA, CD34, CK7, CK19, calponin, and S-100 was performed on all PPSS and on 25 control cases (five carcinomas, ten mesotheliomas, and ten thoracic sarcomas). TLE1 was positive in 11 cases (73.3%); bcl-2 and vimentin in 100%; calponin and CD56 in 26.6%; CD99, CK AE1-AE3, CK19, CK7, and EMA in 80%; and S100 negative in all. The only biphasic PPSS was positive for epithelial markers only in the epithelial component. TLE1 was negative in all control cases. TLE1 is expressed in 73% of PPSS, a value inferior to that reported in STSS, but is highly specific for PPSS. TLE1 may therefore be of value in the differential diagnosis of PPSS, but should be used in a panel of antibodies.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Represoras/metabolismo , Sarcoma Sinovial/metabolismo , Adulto , Anciano , Antígenos CD34/metabolismo , Proteínas Co-Represoras , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Proteínas S100/metabolismo , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/patología , Sensibilidad y Especificidad , Vimentina/metabolismoRESUMEN
BACKGROUND AND AIMS: Syndecan-1 (SDC-1) is a member of the family of transmembrane heparan sulfate proteoglycans, which are involved in cell-cell adhesion and the interaction of cells with the extracellular matrix. Evidence suggests that loss of SDC-1 expression in several benign and malignant epithelial neoplasms is an unfavorable prognostic indicator, but its expression profile in thyroid gland neoplasms remains to be elucidated. The aim of this study was to evaluate SDC-1 expression in papillary carcinomas of the thyroid (PCT) that were both larger and smaller (papillary microcarcinoma) than 10mm, with or without extracapsular extension (PCT-E and PCT-NE). METHODS: The expression of SDC-1 was studied in 62 cases of PCT-E and PCT-NE using a tissue microarrays technique (TMA). SDC-1 positivity was predominantly observed in the cytoplasm of neoplastic epithelial cells and in the stroma of PCT. RESULTS: SDC-1 is expressed in both neoplastic epithelial cells and the stroma. It is more frequently expressed in PCT-E than PCT-NE (p=0.002) and the stromal expression of SDC-1 is more intense in PCT-E that are >10 mm (p=0.026). CONCLUSIONS: The epithelial and stromal expression of SDC-1 observed in this series of PCT suggests that the expression of this protein may be related to extracapsular invasion.
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Carcinoma Papilar/metabolismo , Invasividad Neoplásica , Sindecano-1/metabolismo , Neoplasias de la Tiroides/metabolismo , Adolescente , Adulto , Anciano , Carcinoma Papilar/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias de la Tiroides/patología , Adulto JovenAsunto(s)
Sarcoma Sinovial/diagnóstico , Neoplasias de la Lengua/diagnóstico , Adulto , Biopsia , Núcleo Celular/patología , Citoplasma/patología , Diagnóstico Diferencial , Humanos , Queratina-7/análisis , Queratinas/análisis , Masculino , Mucina-1/análisis , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/patología , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Sarcoma Sinovial/patología , Neoplasias de la Lengua/patología , Translocación Genética/genética , Vimentina/análisisRESUMEN
In this article we present 2 cases of necrotizing sialometaplasia (NS) associated with angiocentric lymphoma of the midline. Immunohistochemical analysis confirmed a T-cell origin, and in situ hybridization in one case revealed its relationship to Epstein-Barr virus. These findings suggest that vascular occlusion by the neoplastic cells produces ischemia, which leads to local infarction contributing to the salivary gland lesion. To our knowledge, the association between angiocentric lymphoma and NS has been previously reported in only one instance, and we suggest that this particular type of lymphoma should be added to the list of related conditions for NS.
Asunto(s)
Infecciones por Virus de Epstein-Barr/complicaciones , Linfoma de Células T/complicaciones , Neoplasias Palatinas/complicaciones , Neoplasias de los Senos Paranasales/complicaciones , Sialometaplasia Necrotizante/diagnóstico , Sialometaplasia Necrotizante/etiología , Adulto , Infecciones por Virus de Epstein-Barr/diagnóstico , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Hibridación in Situ , Linfoma de Células T/patología , Linfoma de Células T/terapia , Linfoma de Células T/virología , Masculino , Neoplasias Palatinas/patología , Neoplasias Palatinas/terapia , Neoplasias Palatinas/virología , Hueso Paladar , Neoplasias de los Senos Paranasales/patología , Neoplasias de los Senos Paranasales/terapia , Neoplasias de los Senos Paranasales/virología , Glándulas Salivales/irrigación sanguínea , Glándulas Salivales/patología , Sialometaplasia Necrotizante/patología , Sialometaplasia Necrotizante/terapiaRESUMEN
Synovial sarcoma is a tumor of the soft tissues with a unique chromosomal translocation t(X;18)(p 11.2;q11.2) that can be detected by polymerase chain reaction in tissue homogenates. The case of a 32-year-old woman with a primary synovial sarcoma of the kidney is described, the diagnosis was corroborated by the recently developed method of in situ polymerase chain reaction (IS-PCR). Synovial sarcoma of the kidney may be confused with other spindle cell tumors, for that reason IS-PCR may be useful to confirm the diagnosis in paraffin-embedded material.
Asunto(s)
Cromosomas Humanos Par 18/genética , Cromosomas Humanos X/genética , Neoplasias Renales/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Sarcoma Sinovial/diagnóstico , Translocación Genética , Adulto , Biomarcadores de Tumor/análisis , Diagnóstico Diferencial , Femenino , Humanos , Riñón/diagnóstico por imagen , Riñón/patología , Riñón/cirugía , Neoplasias Renales/química , Neoplasias Renales/genética , Nefrectomía , Proteínas de Fusión Oncogénica/análisis , ARN Mensajero/metabolismo , ARN Neoplásico/análisis , Sarcoma Sinovial/química , Sarcoma Sinovial/genética , Tomografía Computarizada por Rayos X , Tumor de Wilms/diagnósticoRESUMEN
The aim of this study was to analyze the clinico-pathological and immunohistochemical features of 62 cases of odontogenic myxoma (OM) diagnosed in three Oral Pathology Diagnostic Services in Latin America, as well as to describe the ultrastructural features of three of these cases. OM showed a wide age range (9-71 years), with a mean of 27.97 yr (SD: 11.01) and a male to female ratio of 1:2.2. Mandible was affected in 37 cases (59.6%) and maxilla in 25 (40.4%), with 61.3% located in the posterior region. Thirty-nine cases (62.9%) were multilocular and 23 (37.1%) unilocular. Size ranged from 1 to 13 cm, (mean: 5.2 cm). Thirty-seven multilocular (54.8%) and 6 unilocular lesions (26%) were larger than 4 cm (p<0.05). Epithelial islands were identified in 5 cases (8%) on H&E stained sections, but AE1/AE3 and CK14 disclosed these structures in 15 cases each (24.2%); CK5 was positive in 8 (12.9%); CK7 in 2 (3.2%) and CK19 in only 3 cases (4.8%). All cases were negative for CKs 8 and 18, S-100 protein, NSE and CD68, and showed a low index of expression of Bcl2 and ki-67 proteins (<1%). Mast cell antibodies showed these cells in 45 cases (72.6%). Myofibroblastic differentiation evidenced by myofilaments and fibronexi was found in one case out of the three studied by TEM and 29 cases (46.7%) were positive by immunohistochemistry for alpha actin. In conclusion, only a minority of OM had epithelial islands, and only 3 cases expressed CK 19, indicating an odontogenic epithelium origin. Immunohistochemical and ultrastructural findings suggest that OM is a mesenchymal neoplasm in which several factors may contribute to its pathogenesis, including myofibroblastic differentiation and the participation of mast cell products. However, further investigations are needed to better understand the participation of these elements in this particular neoplasm.
Asunto(s)
Neoplasias Mandibulares , Neoplasias Maxilares , Tumores Odontogénicos , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Niño , Femenino , Humanos , Inmunohistoquímica , Masculino , Neoplasias Mandibulares/metabolismo , Neoplasias Mandibulares/patología , Neoplasias Mandibulares/ultraestructura , Neoplasias Maxilares/metabolismo , Neoplasias Maxilares/patología , Neoplasias Maxilares/ultraestructura , Persona de Mediana Edad , Tumores Odontogénicos/metabolismo , Tumores Odontogénicos/patología , Tumores Odontogénicos/ultraestructura , Adulto JovenRESUMEN
Dermatofibroma (DF) and dermatofibrosarcoma protuberans (DFSP) are dermal tumors whose histogenesis has not been well defined to date. The differential diagnosis in most cases is established in routine H/E sections and may be confirmed by immunohistochemistry, but there are atypical variants of DF with less clear histological differences and non-conclusive immunohistochemical results. In those cases, electron microscopy studies may be useful in establishing the diagnosis. The authors describe in detail the ultrastructural characteristics of 38 cases of DFSP and 10 cases of DF. The objective was to establish the ultrastructural features for differential diagnosis, and to identify the possible histogenesis of both neoplasms. DFSP is formed by stellate or spindled cells with long, slender, ramified cell processes joined by primitive junctions. Subplasmalemmal densities were frequently seen in the processes. Another common finding was the presence of multivesicular buds (MVB), peculiar structures that contain microvesicles abutting from the cell membrane. In contrast, DF is characterized by a proliferation of multiple capillary vessels with prominent endothelium and a perivascular population of ovoid or spindled cells devoid of cell processes. These latter cells featured intracytoplasmic lipid material (p < .001), infrequent subplasmalemmal densities (p < .001), and absence of MVB (p < .001). With the ultrastructural characteristics and the constant expression of CD34 in DFSP, a probable origin in dermal dendrocytes is postulated for this tumor. The histogenesis of DF is less clear, but an origin from FXIIIa modified perivascular dermal dendrocytes is proposed.
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Dermatofibrosarcoma/ultraestructura , Histiocitoma Fibroso Benigno/ultraestructura , Neoplasias Cutáneas/ultraestructura , Capilares/ultraestructura , Membrana Celular/ultraestructura , Dermatofibrosarcoma/irrigación sanguínea , Dermatofibrosarcoma/patología , Diagnóstico Diferencial , Histiocitoma Fibroso Benigno/patología , Humanos , Microscopía Electrónica , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/patologíaRESUMEN
Endometrial stromal sarcoma usually has the gross appearance of a single nodule, multiple masses, or a poorly demarcated lesion with occasional cystic degeneration; however, a multilocular form has not been described in the literature. We report the case of a 25-year-old woman with a cystic multilocular lesion with thin septae measuring 8 cm, discovered by a pelvic ultrasonography. Grossly, it was a multicystic mass located in uterine fundus that was attached to myometrium and showed infiltrating borders. We propose that cystic endometrial stromal sarcoma should be included in the differential diagnosis of cystic uterine tumors.
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Quistes/patología , Neoplasias Endometriales/patología , Sarcoma Estromático Endometrial/patología , Adulto , Quistes/diagnóstico por imagen , Diagnóstico Diferencial , Neoplasias Endometriales/diagnóstico por imagen , Femenino , Humanos , Sarcoma Estromático Endometrial/diagnóstico por imagen , UltrasonografíaRESUMEN
Myofibroblasts are mesenchymal cells with combined function and structure for contraction and collagen synthesis. They are found in reparative responses, nodular fasciitis, fibromatosis, and myofibroblastic sarcoma. Ultrastructurally, myofibroblasts are characterized by a specialized cell surface structure called the fibronexus (FNX). In addition, intracellular collagen fibers (ICF) have been described in nodular fasciitis and fibromatosis, but their origin and nature are still controversial. The aim of the present work was, first, to assess the frequency of FNX and ICF in proliferative myofibroblastic conditions compared to diverse mesenchymal tumors with spindle-shaped cells, and, second, to determine what kind of organelles contain ICF and if they are related to phagocytosis or cell synthesis. Forty-two cases of aggressive fibromatosis and 11 of nodular fasciitis (group A) were compared to 82 spindle-cell mesenchymal tumors of diverse nature (group B) by electron microscopy study. The presence and frequency of FNX and ICF was compared in both groups, and the organelles containing ICF were recorded. FNX and ICF were constantly found in group A (69.8 and 84.9%, respectively), and rarely in group B (0 and 5.12%, respectively). Most frequently ICF were contained in tunnels and phagolysosomes, but also were found in Golgi vesicles and cisternae of rough endoplasmic reticulum. In the majority of cases (75%), ICF were similar to collagen fibers of the extracellular space, but in some cases (22.5%), they were in dissimilar stages of fibrogenesis. Fibromatosis and nodular fasciitis are characterized by proliferation of myofibroblasts and constantly show FNX and ICF. These structures are rarely found in other mesenchymal tumors. The ICF are found in organelles of digestion and also in others related to synthesis and transport.