1/95. Well-differentiated adenocarcinoma, gastric foveolar type, of the extrahepatic bile ducts: A previously unrecognized and distinctive morphologic variant of bile duct carcinoma.Two examples of a rare but distinctive morphologic variant of extremely well-differentiated adenocarcinoma of the extrahepatic bile ducts are reported. One tumor arose in the common bile duct of a 51-year-old man; the other arose in the common hepatic duct of a 27-year-old man. Both tumors were composed predominantly (>95%) of gastric foveolar-type epithelium. Because of their bland nuclear features, low mitotic index, and focal polypoid and lobular architecture, they were initially confused with adenomas. Foci of less-differentiated adenocarcinoma and perineural invasion present in the deep portions of the tumors facilitated recognition. The neoplastic cells and extracellular mucin were periodic acid-Schiff- and alcian blue-positive. By immunohistochemistry, the tumor cells expressed cytokeratins 8 and 20 as well as cathepsin d, as reported in normal foveolar cells. Likewise, p53 overexpression was documented immunohistochemically in both adenocarcinomas, which also stained with the Ki-67 antibody. Despite the well-differentiated nature of the neoplasms and their deceptively benign microscopic appearance, one patient developed recurrence and liver metastasis 5 years after surgery. The other patient is disease-free 2 years following a segmental resection of the common hepatic duct, cystic duct, and gallbladder. The cell phenotype of these tumors can be explained by the ability of the bile duct epithelium to differentiate along gastric cell lines.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/95. Middle ear adenomatous tumor with a predominant neuroendocrine component.A primary adenomatous tumor of the middle ear was examined by light microscopy, ultrastructural and immunohistochemical techniques. In support of its extensive neuroendocrine differentiation, was the diffuse detection of neuron-specific enolase (NSE) and positive immunoreaction with antibodies to chromogranin and synaptophysin. The great majority of tumor cells contained neurosecretory granules and intraluminal mucin production could be focally detected. These characteristics confirm the diagnosis of a middle ear adenomatous tumor (meat) of a biphasic nature and with a prominent neuroendocrine component.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/95. Middle ear adenoma with neuroendocrine differentiation.The lining of the middle ear cleft is normally a thin modified respiratory type mucosa. Normal mucosa of the middle ear is devoid of salivary type seromucous glands. Middle ear adenoma is a rare tumor that seems to be derived from the middle ear mucosa. This tumor has been previously described under a variety of names because of its different nature and biological behavior. We herein report a case of middle ear tumor that shows adenomatous and neuroendocrine features. A 64-year-old woman presented with a history of hearing loss, tinnitus and stuffy feeling of the right ear. The patient was treated two times for ear polyp. She finally underwent a tympanomastoidectomy and there was no evidence of recurrence 18 months after the procedure. Histopathological examination displayed cuboidal and columnar cells, arranged as glands, trabeculae and solid sheets. Neuroendocrine differentiation was revealed by immunohistochemical staining with polyclonal antibodies against neuron specific enolase and chromogranin antigens.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/95. Complementary nature of radiotracer parathyroid imaging and intraoperative parathyroid hormone assays in the surgical management of primary hyperparathyroid disease: case report and review.PURPOSE: This article illustrates the complementary nature of preoperative radionuclide parathyroid imaging and intraoperative rapid parathyroid hormone (PTH) assays in primary hyperparathyroid disease. The authors review the literature on these procedures and compare this protocol and its cost-effectiveness with those of the classic four-gland exploration. MATERIALS AND methods: Preoperative parathyroid imaging with Tc-99m MIBI and intraoperative rapid PTH assays were performed at the time of neck exploration. RESULTS: One of two parathyroid adenomas seen on radionuclide images would have been missed if the authors had relied solely on the initial decrease in PTH assay value to a normal level. CONCLUSIONS: Tc-99m MIBI imaging and intraoperative rapid PTH assays are complementary; when used together, they lessen the likelihood that abnormal parathyroid glands will be overlooked. This experience and that of others suggest these combined procedures are cost-effective.- - - - - - - - - - ranking = 5keywords = nature (Clic here for more details about this article) |
5/95. Pitfall of the accessory spleen.Two patients, one with insulinoma and one with Cushing's syndrome, are presented. Biochemical evaluation readily suggested the correct diagnosis. During radiologic imaging, the anatomic abnormality giving rise to these diseases, i.e. a pancreatic islet cell tumor, and an adrenal adenoma, at first were mistakenly interpreted as an accessory spleen on the basis of specific computed tomography and magnetic resonance imaging appearances. The insulinoma was identified as such during laparotomy, whereas additional jodo-cholesterol scintigraphy revealed the real nature of the lesion in the patient with Cushing's syndrome. Both patients were operated successfully.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/95. Management approaches to adrenal incidentalomas (adrenalomas). A view from Athens, greece.We believe the management of adrenalomas should include the following: 1. A detailed history and physical examination to detect subtle evidence of hormonal hypersecretion or the possibility of metastatic carcinoma 2. Hormonal studies, such as The short dexamethasone suppression test (2 mg of dexamethasone) followed by a high-dose dexamethasone suppression test (8 mg), CRH assay, and analysis of the diurnal cortisol rhythm if serum cortisol is greater than 3 micrograms/dL 24-Hour (or spot) urinary catecholamine metabolites (metanephrine and normetanephrine) plasma aldosterone level and renin activity in the hypertensive or normotensive patient with serum potassium less than 3.9 nmol/L 3. Additional imaging studies, such as MR imaging 131I-iodocholesterol (NP59) scanning to detect a subclinically functioning adenoma or carcinoma (MIBG scanning is rarely indicated) The role of FNA is limited. This modality may be helpful only in the patient with coexistent extradrenal carcinoma to confirm adrenal metastasis. Although genetic and molecular biology studies do not have wide clinical application, they should be encouraged and supported. Once all of these data are collected, the clinician should perform the following two steps: 1. All clearly nonfunctioning adrenalomas that are not suspicious for malignancy should be observed for several years, mainly with hormonal studies, until their secretory and benign nature is confirmed. 2. All patients with adrenalomas with evidence of subclinical function or potential for malignancy (using size, imaging, FNA, and molecular biology criteria) should undergo laparoscopic adrenalectomy for definitive diagnosis and therapy. The age, the overall medical condition, and the anxiety of the patient should be considered in the decision to operate on a patient with an adrenaloma.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/95. MRI and CT of adenomatous tumours of the middle ear.We report three adenomatous middle-ear tumours, an adenoma, an adenocarcinoma and a semimalignant adenomatous tumour, with special attention to CT and MRI findings. In all cases we found small intratympanic masses in which the ossicles were embedded. All showed contrast enhancement and similar signal intensity as brain tissue on T1- and T2-weighted images. The biological nature of the tumours was not reflected by the imaging or operative findings.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/95. Non-secreting atypical parathyroid adenoma.Parathyroid tumors can be divided in adenomas and carcinomas, usually detected by hypercalcemia. We report a case of parathyroid adenoma in a young man, who complained of a pressure in the left neck region. physical examination revealed a firm mass in the neck, without lymphnodes. Although Ca (9.7 mg/dl), phosphorus (3.3 mg/dl) and intact-PTH (49 pg/ml) were normal, imaging techniques (computed tomography scan and sestamibi substraction scan) suggested that the mass could arise from the parathyroid gland. histology and immune staining for chromogranin and parathyroid hormone confirmed the parathyroid nature of the mass. Histological criteria defined the lesion as an atypical parathyroid adenoma. We review the pathology, diagnosis and treatment of parathyroid adenomas in its non-secreting atypical form.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/95. Middle ear adenoma is an amphicrine tumor: why call it adenoma?Middle ear adenoma (MEA) is a rare tumor postulated to take origin from the lining epithelium of the middle ear cavity. The authors report on a case of MEA arising in a 53-year old woman suffering from a sensation of fullness in her left ear, otalgia, and light left-sided hearing loss. Histopathologically, the lesion was composed of cuboidal and polygonal cells displaying a trabecular, tubulo-glandular, and solid pattern of growth. Immunohistochemically, neoplastic cells diffusely stained with anti-vimentin antibodies and were focally positive for chromogranin a, neuron-specific enolase, lysozyme, and cytokeratins AE1/AE3. The majority of tumor cells showed weak and diffuse staining with both anti-PP and anti-ACTH antibodies and intense positivity with anti-glucagon and anti Leu-7 antibodies. Ultrastructural investigation revealed both mucinous-glandular and neuroendocrine differentiation. The authors suggest that the appropriate terminology would be adeno-carcinoid or amphicrine tumor of the middle ear rather than "adenoma," a term that does not reflect its dual nature.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
10/95. genetic heterogeneity and alterations in chromosome 9 loci in a localized region of a functional pituitary adenoma.The molecular alterations reported in pituitary adenomas include mutations at the G(s)alpha in somatotrophinomas, and hypermethylation of the p16 tumor suppressor gene. There are, however, no reports of genomic instability or intratumor genetic heterogeneity in pituitary adenomas. We have studied the microsatellite loci on the short arm of chromosome 9 (9p) and the dna fingerprinting pattern, of adjacent compartments, about 2 mm across, in a functional chromophobe pituitary adenoma secreting growth hormone and prolactin. The microsatellite loci were studied by PCR amplification using locus specific primers, while the dna fingerprinting pattern was studied by randomly amplified polymorphic DNA (RAPD) analysis. Normal leukocyte DNA was taken as control. Only one compartment (Ta) showed alterations in several of the microsatellite loci and in the RAPD pattern vis a vis corresponding normal DNA and also the other two compartments of the tumor. This provides evidence for the localized nature of genomic instability in this tumor.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
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