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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have encountered three cases of a recently recognized form of granulosa cell tumor referred to by Scully as the juvenile type, and we have made ultrastructural observations on one case. This variant is encountered almost exclusively in the first two decades, and is characterized at the optical microscopic level by a macrofollicular or a diffuse, sometime disorderly pattern of growth, often with extensive luteinization and hyperchromatic nuclei. One of our patients developed precocious pseudopuberty. Our ultrastructural observations in this case supported the concept that this tumor is a granulosa cell tumor, and the tumor showed some similarities to previously reported granulosa cell tumors. A spectrum of cells was observed ranging from well differentiated granulosa cells to stromal cells with many intermediate forms present. The stromal cells varied from being fibroblast-like to theca-like. Both granulosa and stromal cells sometimes contained abundant lipid. Evidence of luteinization, i.e. abundant smooth endoplasmic reticulum and tubular mitochondrial cristae, was not noted in either the granulosa or stromal cells. Focal areas of smooth endoplasmic reticulum were found, however, in teh cytoplasm of cells intermediate between granulosa and stromal types. These cells may represent the source of steroid hormone secretion.
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PMID:Juvenile granulosa cell tumor: a clinicopathologic study of three cases with ultrastructural observations. 50 94

A case of an unusual pancreatic tumor with a characteristic papillary-cystic microscopic morphology is presented. Review of four previously reported similar cases suggests a distinct clinical picture of a large abdominal mass occurring in a young person which apparently, after resection, does not rapidly recur. The histopathology of this tumor consists of papillary and cystic patterns, regular homogeneous cells with a few mitoses, glassy eosinophilic cytoplasm, and mucin and PAS positivity. Ultrastructural detail, including eccentric nucleoli, numerous mitochondria, sparse endoplasmic reticulum, and little evidence of secretory activity, suggests a duct cell origin for this rare tumor.
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PMID:Papillary-cystic neoplasm of the pancreas. 53 84

Ultrastructural observations were undertaken on Harding-Passey melanomas in control tumors and in tumors treated with different regimens of colchicine. The treated tumor was made up of pleomorphic cells containing tubulovesicular mitochondria, ribosomes, and rough endoplasmic reticulum. Tumor-bearing mice in Experiment A received a single regimen of colchicine, 0.5 mg/kg/day of 7 days. The treated tumor was subsequently passed through five transplantations in mice. Tumor-bearing mice in Experiment B received colchicine treatment of 0.5 mg/kg/day for 7 days followed by passage through five transplantations. In addition, the mice carrying the tumor received the same colchicine treatment during the second and fourth transplantations. Colchicine treatment resulted in tumor cells of Experiments A and B developing microfilaments, margination of melanin granules, and junctional complexes, considered to be evidence of altered morphologic differentiation in melanocytes. The effects persisted for 10 weeks throughout the five transplantations. The features were more striking in Experiment B animals receiving intermittent therapy.
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PMID:Cytologic features of Harding-Passey melanoma following different regimes of colchicine treatment. 56 21

The ultrastructural features of two "sex cord tumors with annular tubules" are presented. The findings are compared with the reported fine structure of ovarian and testicular stromal cells and the cells of gonadal stromal neoplasms. The predominant cell in the "sex cord tumor with annular tubules" has some of the ultrastructural features found in gonadal stromal cells of either ovarian or testicular type; however, no Charcot-Bottcher crystals, lamellar bodies, crystalloids of Reinke, abundant smooth endoplasmic reticulum or complex plasma membrane interdigitations are observed in the tumor cells to suggest wither Sertoli or Leydig cell origin. The striking similarity between the predominant cell type and granulosa cells, as well as the presence of fibrillary material of the type seen in Call-Exner bodies, suggests a granulosa cell origin for these neoplasms. However, the presence of a sparsely distributed second cell type which closely resembles the dark cells in normal nonluteinized ovarian stroma indicates these tumors may arise from the nonspecialized ovarian stroma.
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PMID:Ovarian sex cord tumors with annular tubules: an ultrastructural study. 56 45

Ultrastructural examination of an alveolar rhabdomyosarcoma revealed that the bulk of the tumor was composed of small polygonal cells containing polyribosomes, short strands of rough endoplasmic reticulum, and variable amounts of glycogen; the cells were joined by small desmosome-like structures. Similar cells, as well as a variety of larger forms which appeared to be derived from the small cells, were observed along the septa; the larger forms developed a copious cytoplasm and occasionally produced myofilaments. Some of these cells were separated from the septa by basement membranes. Giant cells were also present in the alveolar spaces; these formed neither basement membranes nor myofilaments. The septa themselves were composed largely of collagen and fibroblasts. It is suggested that the commonly proposed correspondence of alveolar rhabdomyosarcoma to the myotube stage of muscle differentiation is incorrect; if anything, the overall pattern of the tumor is epithelial-like, and may correspond to the organization of mesenchymal cells at the stage of somite differentiation. The resemblance of the masses of small tumor cells to the cells of Ewing's sarcoma is discussed.
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PMID:Ultrastructural observations on the histogenesis of alveolar rhabdomyosarcoma. 56 50

The mouse lymphatic leukemia L 1210 ascites tumor cells were transplanted every 3rd (L1210/3) or 6th day (L 1210/6) and then examined by an electron microscope. In cytoplasm of L 1210 cells thick bundles of 8 nm filaments were observed. Lysosomes were more numerous in L 1210/6 cells. Results obtained from morphometric datas shown that the relative cell volume of L 1210/6 population was 1.59 time larger as compared with L 1210/3. The index of nuclear volume to cell volume was very similar in both populations. The relative volume of endoplasmic reticulum was more than twice larger in the L 1210/3 population. The cell surface area was larger in the L 1210/6 cells as compared with this in L 1210/3 cells, but the increase in the surface was not proportional to the increase of the cell volume. The relative surface area of endoplasmic reticulum cisternae was smaller in L 1210/6 cells than in L 1210/3 population.
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PMID:The ultrastructural morphology of leukemia L 1210 ascites tumor cells transplanted with different frequency. 57 42

Ultrastructual observations on an unusual gonadal stromal tumor of the testis in a 4-year-old boy with gynecomastia revealed that the tumor cells lacked the abundant smooth endoplasmic reticulum usually found in neoplastic and nonneoplastic Sertoli and Leydig cells. The cells were rich in cytoplasmic microfilaments, with localized dense areas of the type seen in smooth muscle cells as well as intracytoplasmic lipid droplets. It is concluded that the tumor cells show important similarities to the immature fusiform interstitial cells and the peritubular contractile cells present in the normal testis.
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PMID:Unusual gonadal stromal tumor of the testis. Case report with ultrastructural observations. 57 31

A primary meningeal mesenchymal chondrosarcoma initially resembled an angioblastic meningioma because the typical chondroid islands were not demonstrable. Cartilage was seen only in an intracerebral recurrence and in subsequent extracranial metastases. Ultrastructural examination of noncartilaginous regions of the tumor demonstrated mesenchymal cells with features suggestive of cartilaginous differentiation, viz, scalloped cell membranes, sac-like distension of abundant rough endoplasmic reticulum, and a matrix containing fibrillary and finely granular material. Features of meningeal or pericytic cells were not seen.
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PMID:Primary meningeal mesenchymal chondrosarcoma. 58 58

A case of botryoid sarcoma of the common bile duct in a 4-year-old girl was reported. Electron microscopic examination disclosed that the neoplasm consisted of three types of cells: polygonal, elongated, and small cells. The former two contained moderate to large amounts of poorly developed myofibriles in the cytoplasm with occasional A, I and Z-bands. The small cells contained mitochondria and dilated rough endoplasmic reticulum but few myofilaments. Deposits of glycogen granules were constant components of the neoplastic cells. Mitosis was striking in the small cells. Abnormal multilaminar endoplasmic reticulum was observed in the small cells in the mitotic stage.
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PMID:Ultrastructure of botryoid sarcoma of the common bile duct. 59 Jul 3

Snell adrenocortical tumor 494 was implanted into male Sprague-Dawley rats and recovered 7, 14, 21, 28 or 35 days following initial detection by palpation (7-10 days following transplantation). Electron microscopic, stereological and biochemical analyses of the tumor were compared to adrenals of normal animals to serve as a baseline for further studies of the effects of chemotherapeutic agents on tumor cells. Tumor cells possessed oval or elongated mitochondrial profiles with tubular cristae, one or two very large (greater than 5 micrometer) lipid droplets, abundant ribosomes and coated vesicles, and sparse rough and smooth endoplasmic reticulum. Stereologic evaluation revealed that tumor lipid volume was 41% and mitochondrial volume 29% that of the normal adrenal controls. Tumor nuclei were 2.5 times larger than adrenocortical nuclei while cellular volumes were similar. On a net weight basis, tumor cholesterol was 55%, cholesterol ester 2.2%, and lipid phosphate 25% of respective mean values for normal adrenal glands. The tumor cholesterol: cholesterol ester ratio progressively decreased with time but remained 18-fold greater than the normal adrenal. Plasma corticosterone levels in tumor-bearing rats were elevated 3-fold by 14 days and initial detection. The adrenals of the tumor-bearing host exhibited marked involution, the extent of which was directly related to tumor size.
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PMID:Rat adrenocortical carcinoma 494: an integrated structural, stereological, and biochemical analysis. 63 20


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