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

An autopsy case of radiation-induced intracranial malignant fibrous histiocytoma (fibroxanthosarcoma) is reported. The tumor developed in the region of the sella turcica 11 years after high dose radiotherapy of a chromophobe adenoma of the pituitary. The tumor had infiltrated the base of the brain as well as the base of the skull. Metastases were not found. The tumor was composed of an admixture of bizarre fibroblasts, histiocytes and giant cells, xanthoma cells and siderophages, with a storiform fibrous stroma. This appears to be the first documented instance of a malignant fibrous histiocytoma occurring intracranially after local x-irradiation.
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PMID:Radiation-induced intracranial malignant fibrous histiocytoma. 18 Nov 26

Six cases of Cushing's syndrome with adrenocortical tumors which showed a variety of responsiveness to ACTH were investigated in relation to their clinical pictures and laboratory findings. Abnormal responses to ACTH in tumors was analyzed by in vitro experiments with surgically obtained tumor tissues, and the ACTH responsive mechanism of the tumors was discussed. An 8 hour intravenous ACTH infusion test showed that three of these patients were ACTH responsive, and the other three unresponsive. Histological observation of the tumors revealed that ACTH responsive tumors were adenomas and that ACTH unresponsive tumors were "black adenomas" in two and a carcinoma in one. To investigate possible factors which might account for these differences in ACTH responsiveness, tumor specimens of each one of the responsive and unresponsive adenomas, and a carcinoma were subjected to in vitro studies. When incubated with ACTH or cyclic AMP, tissue sections of a responsive adenoma enhanced cortisol secretion, while that of a black adenoma failed to show any change. Steroidogenesis by carcinoma sections were significantly suppressed in the presence of ACTH or cyclic AMP. Cycloheximide abolished a stimulatory effect of ACTH and cyclic AMP on steroidogenesis in a responsive adenoma without affecting its basal secretion of cortisol. Steroidogenesis by unresponsive tumors (an adenoma and a carcinoma) were decreased by cycloheximide. Since the conversion of cholesterol to pregnenolone, the rate limiting step in steroidogenesis, takes place in adrenal mitochondria, the effect of cyclic AMP on pregnenolone formation from 14C-cholesterol by mitochondrial fractions of these tumors was examined. Cyclic AMP stimulated pregnenolone formation by mitochondrial fraction of an ACTH responsive adenoma, while with that of an unresponsive adenoma pregnenolone formation was not affected. Pregnenolone formation by cancer mitochondria was significantly suppressed by cyclic AMP. These results suggest that the unresponsiveness to ACTH of these tumors might be explained by the ineffectiveness of cyclic AMP to stimulate pregnenolone formation by tumor mitochondria, and that the steroidogenic pathway in unresponsive tumors are in an enhanced state even without cyclic AMP. It should be mentioned that all unresponsive adenomas gave a characteristic appearance of a "black adenoma". Histologically, tumors were composed of compact cells with abundant lipofuscin granules. The possible relationship between the ACTH responsiveness of adrenocortical tumors and some clinical pictures caused by them was also noticed. ACTH unresponsive adenomas resulted in shorter duration, severer conditions of the disease and higher 17-ketosteroid excretion than responsive adenomas. The growth of unresponsive tumors seemed faster than that of responsive ones.
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PMID:[Studies on the responsiveness of human adrenocortical tumors to ACTH the clinical and experimental observations (author's transl)]. 18 66

The literature on bronchial adenoma has been reviewed and controversy found to exist about certain aspects of these tumors, particularly their malignancy. A retrospective study of 79 cases managed in Edinburgh since 1946 is presented. Seventy-one were of the carcinoid type, 7 were adenoid cystic carcinomas, and there was a single example of mucoepidermoid carcinoma. All types show a definite malignant potential, greatest in the rare mucoepidermoid tumor and least in the common carcinoid variety. Adenoid cystic carcinoma occupied an intermediate position in frequency and malignancy.
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PMID:The malignancy of bronchial adenoma. 18 62

Seventy-eight patients with insuloma diagnosed between 1959 and 1968 in Sweden were studied for neoplasia in other organs. Twenty-one patients had beta-cell islet tumors, 14 Zollinger-Ellison's syndrome and non-beta-cell islet tumors, while no endocrine activity was demonstrated in 43 patients. Of the last-mentioned group, 9 patients had co-existing disease of other endocrine organs. In 10 patients, non-endocrine organs were found to be affected by malignant diseases. It appears probable that the tissue of the pancreatic islets, like parathyroid tissue, can react with hyperplasia with a later development of adenoma, secondary to tumors in other organs.
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PMID:Insulomas and multiple endocrine neoplasia. 18 32

The myoepithelioma is a rare salivary gland tumor composed nearly exclusively of myoepithelial cells. A case occurring on the palate of a 22-year-old man is reported. Electron microscopic findings of occasional desmosomes, a basal lamina associated with the plasma memb;rane, and perinuclear cytoplasmic filaments confirmed the diagnosis. The myoepithelioma appears to resemble the pleomorphic adenoma clinically and may be a development variant of the pleomorphic adenoma.
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PMID:Myoepithelioma. Review of the literature and report of a case with ultrastructural confirmation. 18 7

Within the last several years, previously rare liver tumors have been seen in young women using oral contraceptive steroids. The Registry for Liver Tumors Associated with Oral Contraceptives at the University of California, Irvine, has clearly identified 27 cases. The recent literature contains 44 case reports. Common to these 71 cases has been a histopathologic diagnosis of focal nodular hyperplasia, adenoma, hamartoma, and hepatoma. Significant statistical etiologic factors include prolonged uninterrupted usage of oral contraceptive steroids. Eight deaths and liver rupture in 18 patients attest to the seriousness of this new potentially lethal adverse phenomenon.
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PMID:Etiologic factors in the pathogenesis of liver tumors associated with oral contraceptives. 18 39

A 2 1/2 year old girl with virilization and advanced bone age was found to have a leftsided adrenocortical adenoma. The secretion of mainly androgens besides estrogens was not suppressible with dexamethasone. Plasma cortisol levels were not elevated but did not show any circadian rhythm. The tumor was localized by retroperitoneal instillation of gas, intravenous urography and tomography. After complete removal of the tumor the originally strongly elevated excretion of 17-ketosteroids sank back to normal, the acceleration of skeletal development slowed down. The right adrenal cortex was not atrophic, 2 1/2 years after the operation the child is well and without evidence of recurrent disease. Differential diagnosis as well as ultrastructor and histology of the tumor are discussed with reference to the literature.
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PMID:[Adrenocortical adenoma in a 2 1/2 year old girl causing virilization and accelerated growth. Clinical and morphological results (author's transl)]. 19 May 31

Twenty-four patients with bronchial adenoma seen over a 20-year period are reviewed. Follow-up data was available in all patients. They included 19 with carcinoid, 2 with adenoid-cystic carcinoma, and 3 with muco-epidermoid carcinoma. Recurrent pulmonary infection, cough and hemoptysis were the most common clinical manifestations. Surgical resection was performed in all but one patient, who was treated by irradiation; bronchoplastic and conservative resectional procedures were used in 5 patients with carcinoid adenoma. Carcinoid tumors are considered to be very slowly-growing malignant neoplasms that sometimes give rise to metastases to regional lymph nodes. Such metastases were present in only one patient. All patients are alive and well. Adenoid-cystic carcinoma is a more aggressive tumor with a tendency to recur. Much of the difficulty in its treatment is due to its close proximity to the bifurcation of the trachea. One patient was operated upon three times for local recurrences and ultimately died from respiratory failure after the third operation. The other patient received radiation therapy with cobalt and is well, without recurrence, 3 years after the treatment. The 3 muco-epidermoid carcinomas were histologically similar to such tumors of salivary glands but behaved clinically like highly malignant tumors, no patients surviving 8 months after resection. The term bronchial adenoma is a misnomer. The neoplasms grouped under this heading should be called carcinoid adenoma, adenoid-cystic carcinoma, and muco-epidermoid carcinoma and considered as separate entities, since the ultimate course and prognosis is definitely different.
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PMID:[Bronchial adenoma]. 19 6

An adrenocortical adenoma associated with adrenogenital syndrome in a two-year-old boy was investigated light and electron microscopically. Urinary 17-ketosteroid excretion was considerably elevated and unresponsive to dexamethasone administration. The level returned to normal after surgical removal of the tumour. Adenomatous cells display striking cellular and nuclear pleomorphism. Megalocytes with huge nuclei and nucleoli frequently occur. Deep cytoplasmic indentations cause nuclear pseudoinclusions and bizarre shape of the nuclei. True nuclear inclusions are also seen, as well as nuclear fragmentation. Cytoplasmic organelles show striking morphological alterations. Mitochondria with lamellar and tubular cristae are transformed into round or ovoid organelles of vesicular type. Their internal compartment is reduced, matrix material increases relatively, and mitochondrial inclusion bodies develop. Mitochondrial inclusions are identified as corresponding to fuchsinophil (siderophil or argyrophil) granules seen in the light microscope. Their staining properties indicate their glycoprotein nature. Vesicular profiles of smooth endoplasmic reticulum predominate and stacks of rough endoplasmic reticulum are transformed into tubules and vesicles. In Golgi regions, only vesicular elements are enriched. Lipid droplets are scarce. It was not possible to demonstrate histochemically catalase activity in microbodies. Dense bodies only occur in small, undifferentiated tumour cells. Multivesicular bodies, autophagosomes and residual bodies are rare. Lipofuscin is absent. Tumour cells are thought to derive from a population of undifferentiated cells ("germinative tumour cells"). Their morphological features and organelle equipment during a hypothetical course of differentiation and following dedifferentiation is described and discussed with respect to exceeding androgen synthesis.
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PMID:Fine structure of a virilizing adrenocortical adenoma. 19 90

A consecutive series of 12 benign hepatic lesions in women consisted of six cases of focal nodular hyperplasia and six cases of liver cell adenoma. Five of the six women with liver cell adenoma and two of the six with focal nodular hyperplasia had taken orally active contraceptive hormones. These few cases reflect a similar impression gained from a critical analysis of the literature, namely, that focal nodular hyperplasia may be unrelated to the oral administration of contraceptive hormones, whereas the increase in liver cell adenoma reported in recent years is probably related to such therapy. Two women with liver cell adenomas were asymptomatic six and four years after incomplete resection of the tumor. These are the longest intervals thus far reported for uncomplicated survival in incompletely resected liver cell adenoma.
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PMID:Benign hepatic lesions and orally administered contraceptives. A report of seven cases and a critical analysis of the literature. 19 59


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