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PubMed1977

Ultrastructure of atypical fibroxanthoma.

Electron microscopic examination of an atypical fibroxanthoma (AFX) confirmed the fibrohistiocytic nature of this lesion. Ultrastructural evidence suggested a transition from fibroblasts to large giant cells with intermediate forms exhibiting features of both. A comparison of AFX ultrastructural features to those of other similar neoplasms suggested a possible relationship to malignant fibrous histiocytoma. As diagnosed by light microscopy, AFX probably represents a spectrum of neoplasms; this concept is discussed. It is urged, when possible, that electron microscopy be performed on lesions diagnosed as atypical fibroxanthoma since ultrastructure studies represent the most valid basis on which a correct diagnosis can be made.

Aged↗

PubMed1978

Ultrastructure of infantile hemangioendothelioma of the liver.

A two-month-old female presented with hepatomegaly 5 cm below the right costal margin. Resection of a 6 cm hepatic mass demonstrated an infantile hemangioendotheliom (IHE). This documents for the first time the ultrastructural features of an IHE of the liver. Ultrastructural examination showed large numbers of vascular channels of varying sizes lined by abnormal endothelial cells. An incomplete basal lamina separated the endothelial cells from the extracellular material and there were no associated pericytes. The intervascular area contained abundant collagen fibers, fibrils, and cells ultrastructurally similar to fibroblasts. The relationship of structure to certain clinical features of this lesion is discussed.

Connective Tissue↗

PubMed1979

A comparative study including ultrastructure of intramuscular myxoma and myxoid liposarcoma.

The clinicopathological data of ten intramuscular myxomas (IMM) and three myxoid liposarcomas (MLS) are presented with emphasis on their ultrastructure. Electron microscopy of three of the IMM demonstrated the principal cell of the IMM to be similar to a fibroblast with prominent R.E.R., well-developed Golgi apparatus and cytoplasmic filaments. Intracytoplasmic lipid droplets were very rare. The matrix was composed of finely granular material, collagen fibers, fibrils and few capillaries. In contrast with the IMM, the cytoplasm of the MLS contained extensive lipid droplets. Capillaries were very abundant and in close proximity to the lipoblasts. The distinction between an IMM and MLS is usually clear-cut by light microscopy. Dissimilar ultrastructural features provide additional data to separate these two tumors. Ultrastructure confirmed Enzinger's impression that the cell of origin of the IMM is similar to a fibroblast with features that support the hypothesis that these cells are the source of production of the excessive amount of mucopolysaccharides in the matrix.

Adult↗

PubMed1979

Malignant hemangioendothelioma (angiosarcoma) of the salivary gland: an ultrastructural study.

A case of malignant hemangioendothelioma (angiosarcoma) of the submaxillary salivary gland is reported and its microscopic and ultrastructural features are described and compared to previous reports of angiosarcoma arising in other locations. These tumors may often contain areas of solid sheets of cells without vascular characteristics and may be confused with poorly differentiated carcinoma or other sarcomas. The ultrastructural features of angiosarcoma are compared to other poorly differentiated tumors. It is concluded that the ultrastructural features of angiosarcoma are distinctive and aid in the diagnosis of this neoplasm.

Aged↗

PubMed1979

A nonfunctioning paraganglioma of vagus nerve: an ultrastructural study.

The clinical, histological, and ultrastructural aspects of a cervical paraganglioma of the vagus nerve, in a 66-year-old white man, have been discussed in detail. Ultrastructurally, the tumor chief cells contained characteristic membrane-bound and dense-cored neurosecretory granules which ranged in size from 85 millimicron to 190 millimicron. Unlike earlier ultrastructural reports, the present study showed the presence of sustentacular or supporting cells. These cells were smaller, darker, polymorphic, and were commonly located at the periphery of a single or group of chief cells. Furthermore, unlike earlier reports on vagal paragangliomas, nonmyelinated nerve fibers and an occasional axon were identified in the present fine structure study.

Aged↗

PubMed1979

Non-Hodgkin's lymphomas: an ultrastructural study correlating morphology with immunologic cell type.

Ultrastructural studies were performed on 40 B-cell and 14 T-cell lymphomas of non-Hodgkin's type (NHL). Most B-cell lymphomas were comprised of neoplastic cells with morphologic features compatible with a follicular center cell origin. Dendritic reticulum cells and their desmosome-associated processes, characteristic of germinal centers, were observed in all 11 cases of nodular poorly differentiated lymphocytic lymphoma and in one of two cases of nodular "histiocytic" lymphoma, but were not identified in the lymphomas with a diffuse growth pattern. Desmosomes were observed between dendritic reticulum cells and were not found between lymphoid cells. Large neoplastic cells comprising lymphomas of "histiocytic," mixed lymphocytic "histiocytic," and "undifferentiated" types were characterized ultrastructurally and immunologically as lymphoid cells. Malignant lymphomas of well and moderately well differentiated lymphocytic types (7 cases) revealed B-cell markers, and represented a distinct homogenous group of neoplasms, with electron microscopic features most closely resembling follicular cuff lymphocytes. T-cell malignancies included lymphoblastic lymphomas (3 cases), large cell ("histiocytic") lymphomas (4 cases), lymphoepithelioid cell ("Lennert's") lymphomas (2 cases), mycosis fungoides (3 cases) and diffuse poorly differentiated lymphocytic lymphomas (2 cases). A consistent finding in the T-cell proliferations was the presence of small and/or large lymphoid cells with extremely irregular and/or convoluted nuclei, which occurred in varying proportions and with variable degrees of nuclear complexity. The nuclear irregularity evident in the neoplastic T cells was distinguishable from that observed for lymphoid cells of B-cell lymphomas. In comparing the cytoplasmic features of the T- and B-cell neoplasms ultrastructurally, the only distinguishing feature was the presence of well developed granular endoplasmic reticulum with dilated cisternae, i.e., plasmacytoid features, predictive of a B cell origin.

Adolescent↗

PubMed1979

Olfactory neuroblastoma (esthesioneuroblastoma): a light and ultrastructural study of two cases.

Olfactory neuroblastoma is a malignant neoplasm with a varied biological behavior. Its clinical course is unpredictable and there is no correlation between its microscopic features and biological behavior. The present study deals with light and ultrastructural characteristics of two cases of olfactory neuroblastoma of the nasal cavity. In one patient, the definitive diagnosis was established on the basis of ultrastructural features of the lesion. The most consistent fine structural findings were the presence of intracytoplasmic densecored neurosecretory granules, "true" and "pseudo-" rosettes, and the neuritic processes emanating from the tumor cells. On the basis of their biochemical, histochemical, and ultrastructural characteristics, olfactory neuroblastomas are similar to neuroblastomas arising from the adrenals or sympathetic nervous system. These findings, therefore, support the hypothesis that olfactory neuroblastomas are most likely of neural crest origin and thus belong to a group of neoplasms collectively known as "apudomas" or neurocristomas. The literature review strongly favors combined surgery and postradiation as the most effective treatment of olfactory neuroblastoma.

Aged↗

PubMed1982

Ultrastructural studies of xenografted human germ cell tumors.

Xenografts have been established in immune-suppressed mice from three embryonal cell carcinomas, two yolk sac carcinomas, and a 'seminoma-like' tumor that produces alphafetoprotein. The ultrastructural features of these xenografts have been studied in detail and compared with human germ cell tumors removed from patients. A spectrum of ultrastructural differentiation has been demonstrated for tumors of the same histologic classification (embryonal cell carcinoma) and within individual tumors. Cells with ultrastructural appearances intermediate between seminoma and yolk sac carcinoma and between embryonal cell and yolk sac carcinoma have been demonstrated, and their potential implications for tumor histogenesis are discussed.

Adult↗

PubMed1982

An ultrastructural study of angiomatoid fibrous histiocytoma.

We studied the electron microscopy of two tumors which clinically and histologically conformed to what has been described as angiomatoid fibrous histiocytoma, a tumor thought to be of fibrohistiocytic origin. The ultrastructure of one tumor was that of a cellular angioma and the second tumor a vascular lesion with fibroblasts and histiocyte-like mononuclear cells. Our findings suggest that angiomatoid fibrous histiocytomas are basically vascular tumors with fibroblasts and other cells as secondary participants in some lesions. The behaviour of angiomatoid fibrous histiocytoma cannot be predicted from histology. Our findings of different ultrastructural components in histologically non-separable tumors lead to a question whether different ultrastructural composition is correlated with different biological behavior of these tumors. Further studies of similar cases are required if tumor morphology is to be correlated with clinical behavior.

Child↗

PubMed1983

Large-cell calcifying sertoli cell tumor of the testis. An ultrastructural, immunocytochemical, and biochemical study.

This report describes the ultrastructural and hormonal characteristics of the recently described large-cell calcifying Sertoli cell tumor of the testis, a rare subtype of pure Sertoli cell tumor. The ultrastructural findings showed similarity to normal Sertoli cells, pure Sertoli cell tumors, Sertoli cells in azoospermic human testes, and the Sertoli cell component of Sertoli-Leydig cell tumors. Ultrastructure indicated features common to steroid-producing cells. Testosterone and estradiol were demonstrated in the tumor by immunocytochemical and biochemical methods.

Basement Membrane↗

PubMed1984

Immunohistochemical and ultrastructural analysis of the proliferating cells in histiocytosis X.

The cellular nature of the proliferating histiocytes in 6 cases of histiocytosis X was studied immunohistochemically and ultrastructurally. Immunohistochemically, S-100 protein was detected both in the cytoplasm and the nuclei of histiocytosis X cells as well as Langerhans cells in normal oral epithelium. These cells were always negative for lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin and immunoglobulins. S-100 protein was not detected in lysozyme-positive histiocytes and multinucleated giant cells often showed the signs of phagocytosis. Thus, S-100 protein appears to be a useful immunohistochemical marker for histiocytosis X cells. Ultrastructurally, Birbeck granules noticed in histiocytosis X cells were never seen in the phagocytic histiocytes with numerous lysosomes and phagosomes. These results emphasized the heterogeneous nature of the proliferating histiocytes involved in the lesions. Since histiocytosis X cells share characteristics, not only ultrastructurally but also immunohistochemically, with Langerhans cells, the hypothesis that histiocytosis X may be fundamentally an abnormal proliferation of Langerhans cells has been further supported.

Cell Division↗

PubMed1984

Ultrastructural and immunohistochemical studies of bronchiolo-alveolar carcinoma.

A detailed ultrastructural study was made of seven cases of bronchiolo-alveolar carcinoma, and the findings were correlated with histochemical and immunohistochemical data. By electron microscopic examination all seven tumors displayed glandular differentiation, manifested by the presence of microvilli and intercellular junctions, with or without mucin production. Variable proportions of tumor cells retained ultrastructural characteristics of alveolar type II cells and Clara cells. In addition, some tumor cells revealed desmosomes and tonofilaments consistent with squamous differentiation. Immunohistochemical evaluation was carried out using a peroxidase-antiperoxidase technique and specific antibodies against surfactant high molecular weight glycoproteins, keratin proteins, IgA + secretory piece, carcinoembryonic antigen (CEA), human chorionic gonadotropin (HCG), and alpha-fetoprotein (AFP). Four tumors with type II cell-like differentiation stained with anti-surfactant glycoprotein sera. All seven tumors stained focally with anti-keratin and IgA + anti-secretory piece antibodies, and diffusely with CEA. These tumors failed to stain with antisera against HCG and AFP. It is concluded that bronciolo-alveolar carcinomas are primarily composed of cells with alveolar and bronchiolar cell differentiation. Adequate criteria were established for ultrastructural identification of tumor cells with differentiation to type II alveolar cell or Clara cell. Moreover, the findings of this study indicate that the surfactant glycoprotein marker, when present in a given tumor either diffusely or focally, is diagnostic of bronchiolo-alveolar carcinoma.

Adenocarcinoma↗

PubMed1985

Adamantinoma of the tibia. An ultrastructural and immunohistochemical study.

The light microscopic, ultrastructural, and immunohistochemical characteristics of two tibial adamantinomas are presented. The immunohistochemical studies utilized specific antibodies against Factor VIII-related antigen and keratin protein, considered as markers for endothelial and epithelial cells, respectively. These revealed positive staining for keratin in the tumor cells of both cases, whereas Factor VIII was not found in either. Ultrastructurally, both tumors had tonofilaments, desmosomes, gap junctions, microvillous-like projections, and basement membranes. Patient 1 had disease that was histologically of the classic spindle cell type; the disease of Patient 2 was atypical and closely resembled an epithelioid angiosarcoma. Immunohistochemical and ultrastructural findings in each case indicate an epithelial component in tibial adamantinoma.

Adolescent↗

PubMed1986

Krukenberg tumors of the ovary. Ultrastructural, histochemical and immunohistochemical studies of 15 cases.

The ultrastructural, histochemical, and immunohistochemical characteristics of 12 classical signet ring cell Krukenberg tumors (CKT) and three tubular Krukenberg tumors (TKT) were evaluated and related to their possible influence on the ovarian stroma. In CKT, single signet ring cells predominated over lumen-forming cells and contained ultrastructural and histochemical characteristics similar to goblet cells in colonic and ovarian mucinous adenocarcinomas. In TKT, lumen-forming nonsecretory and secretory signet ring cells were prominent. Rare argentaffin cells were found in TKT but not in CKT. Cells in both CKT and TKT produced neutral and sialomucins. The stroma contained extracellular mucin, hypertrophied stromal fibroblasts and myofibroblasts, and in two cases stromal lutein cells with steroidogenic type ultrastructure. It appears that Krukenberg tumors are made up exclusively of intestinal type cells. Based on cell differentiation, TKT is better differentiated than CKT. Hypertrophy and hyperplasia of ovarian stromal cells may occur in response to malignant growth and/or the extracellular mucinous products of malignant cells and may play a role in the control of tumor invasiveness. None of the 15 cases were immunohistochemically positive for chorionic gonadotropin, placental lactogen, or luteinizing hormone. These hormones are suspected to be related to stromal luteinization in KT.

Adult↗

PubMed1987

Histochemical and ultrastructural study of copper-binding protein in hepatocellular carcinoma.

Orcein-positive hepatocellular material (OPHM), found in 18 of 44 hepatocellular carcinomas (HCC), was compared histochemically and ultrastructurally with similar granular materials in other liver diseases. OPHM was not found in 15 control livers, 45 metastatic liver cancers or ten cholangiocellular carcinomas. OPHM in HCC was stained with orcein when the tissue sections were preoxidized. In addition, it was positively stained with rhodanine and rubeanic acid for copper. These findings were identical to the OPHM in Wilson's disease, in primary biliary cirrhosis and in neonatal livers. Seven of 12 resected HCC revealed cytoplasmic dense bodies ultrastructurally in which an x-ray microanalyzer demonstrated copper. OPHM in HCC, a granular accumulation, was concluded to be rich in copper-protein complex, and might correspond to dense bodies derived from lysosome ultrastructurally. The pathogenesis and biologic significance of this copper overload in a number of HCC are also discussed.

Carcinoma, Hepatocellular↗

PubMed1990

Carcinosarcoma of the gallbladder. A case report with immunohistochemical and ultrastructural studies.

The authors present the histologic features, immunohistochemical findings, and ultrastructure of a carcinosarcoma of the gallbladder containing rhabdomyosarcoma as a mesenchymal element. A pedunculated polypoid tumor protruded into the lumen from the fundus of the gallbladder. The neoplasm contained two divergent components. One was malignant mesenchymal tissue with rhabdomyoblastic differentiation; the other was ordinary adenocarcinoma which was observed predominantly at the base of the polyp. Immunohistochemically, the cytoplasm of the rhabdomyoblasts stained with anti-myoglobin, myosin, and muscle actin antibodies. Ultrastructurally, there were a large number of malignant mesenchymal tissues in which various stages of differentiated rhabdomyoblasts were noted. Ultrastructural study was particularly valuable for the identification of sarcomatous elements.

Carcinosarcoma↗

PubMed1975

Ultrastructure of the early ovary and testis in pig embryos.

Pig embryos aged 26-27 days were used for an ultrastructural study of the early ovary and testis. Sex was identified by both chromosomal analysis and gonadal histology, with consistent results. The gonads occupied their original site in the medial coelomic angles in both sexes. The female gonad was composed of three tissues: the surface epithelium, the gonadal blastema and the mesenchyme. The gonadal structure was similar to that seen earlier at the age of 24 days. At 26 days the testis had distinctly differentiated into four tissues. The new components were the testicular cords and the interstitium, both derived from the gonadal blastema. The testicular cords resembled anastomosing sheets more than cords. The ultrastructure of the tissues and their cell types are described and compared to the previous indifferent stage at the age of 24 days. The cells of the surface epithelium, of the primitive cords, of the mesenchyme, and the primordial germ cells had an ultrastructure that was similar in both sexes. The sustentacular cells of the testicular cords resembled the primitive cord cells and the spermatogonia were similar to the primordial germ cells. No Leydig cells were present yet. The process of testicular differentiation is described on the basis of the present and a previous study, and a new hypothesis, based on the vascular organization, is presented.

Animals↗

PubMed1981

Characterization of seasonal changes in prolactin and growth hormone cells in the hypophyses of white-tailed deer (Odocoileus borealis) by ultrastructural and immunocytochemical techniques.

Prolactin and GH cells were identified in thin sections taken from the adenohypophyses of adult male (6) and female (8) white-tailed deer, collected during all seasons of the year, by locating portions of the same cells in adjacent thick plastic sections immunostained for either PRL or GH. Growth hormone cells were round to ovoid in shape and filled with dense spherical secretory granules which ranged in size from 168 to 682 nm, with a mean diameter of 367 +/- 18 nm (X +/- SD) in the 14 glands studied. No apparent seasonal changes were evident in the ultrastructural appearance of GH cells. Prolactin cells were small and angular in shape during the winter months and contained only a few small secretory granules. By early summer, they wee markedly hypertrophied, round to oval in shape, and densely packed with large spherical secretory granules. The increase in size of PRL secretory granules was most prominent in pregnant females in May, when their mean diameter was approximately double than in midwinter. The ultrastructural appearance of PRL cells in September was similar to that of cells studied in March. The size distribution of PRL secretory granules overlapped that of the GH granules, ranging from 114 to 564 nm, and the mean diameter was 246 +/- 53 nm, calculated from all 14 individual glands. Our observations suggest that the synthesis and secretion of PRL are closely linked to photoperiodic changes in this species, and they demonstrate the necessity of using specific immunocytochemical techniques in the ultrastructural identification of pituitary acidophils, and of specifying the time of year and location (specifies photoperiod) in studies concerning PRL physiology, particularly when dealing with wild animal populations.

Animals↗