Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thirty-four cases of microcystic adenoma of the pancreas were studied. These benign tumors have traditionally been classified as cystadenomas, but have not been clearly distinguished from those cystic neoplasms of the pancreas that have a significant malignant potential. Microcystic adenomas are benign, usually large (mean diameter 10.8 cm), and are composed of many tiny cysts lined by small cuboidal cells containing glycogen but little or no mucin. The tumor may be found incidentally at autopsy or, more commonly, may manifest as an abdominal mass with some associated local pain or discomfort. There is no sex predilection. The patients are usually elderly, both mean and median ages being 68. A microcystic pattern is apparent both grossly and microscopically. Electron microscopy confirms the presence of intracytoplasmic glycogen and the epithelial character of the cells. Follow-up data (mean 6.4 years), available in all cases, indicate that when these tumors occur in the head of the pancreas, fatalities may result either from complications of radical surgery or from gastrointestinal or biliary obstruction. When the tumors occur in the body or tail of the pancreas, biopsy alone may be sufficient.
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PMID:Microcystic adenomas of the pancreas (glycogen-rich cystadenomas): a clinicopathologic study of 34 cases. 63 43

Loss of O-acetyl substituents from sialic acid expressed in mucin secreted by hyperplastic polyps (21), adenomas (9), a mixed polyp (1) and adenocarcinomas (41) of the colorectum was investigated by mucin histochemistry (diastase PAS and mild PAS) and by lectin histochemistry (Arachis hypogaea or peanut agglutinin) with (nPNA) and without (PNA) prior neuraminidase digestion. Mild PAS and nPNA reactivity were closely correlated, indicating that loss of O-acetyl substituents at C7, C8 and C9 (hence mild PAS positive) and at C4 (hence neuraminidase labile) occur pari passu. These sialic acid alterations were characteristic of mucin secreted by both adenocarcinoma and hyperplastic polyp. The same changes occurred patchily or focally in adenoma. Five "serrated" adenocarcinomas resembled the hyperplastic polyp both morphologically and histochemically. Luminal secretions within cancers were classified as mucin-like (type I) and non-mucin-like (type II). Mild PAS was the most specific technique for mucin-like intraluminal material. However, accumulated luminal secretions (type I or II) and intracytoplasmic lumina were quite specific features of colorectal cancer and could be effectively highlighted by means of dPAS. PNA reactivity without prior neuraminidase digestion showed a distribution unlike nPNA. Whilst PNA expression was more cancer specific than either mPAS or nPNA, it was observed mainly in cancers secreting little or no mucus, thus limiting its value as a tumor marker.
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PMID:Sialic acid and epithelial differentiation in colorectal polyps and cancer--a morphological, mucin and lectin histochemical study. 128 63

Three human mucin cDNAs (Muc-1, Muc-2, Muc-3) have recently been cloned and sequenced. The major portion of each mucin consists of sequences repeated in tandem along the protein. Three mucins are distinct due to differences in tandem repeat length, lack of sequence homology and different chromosomal locations of their genes. Since altered mucin glycosylation occurs in cancer resulting in exposure of core carbohydrate, we postulated that increased exposure or other alteration of core peptide structure may occur in cancerous tissues. Antibodies against Muc-1, Muc-2, Muc-3 tandem repeats were used for immunohistochemical analysis of normal, non-malignant and cancer tissues. The results indicate that in normal tissues, only Muc-2 expressed, while in cancerous tissues all three mucin core peptides were significantly accumulated, All of the three mucin core peptides increasingly expressed in adenoma, dysplasia epithelium and active ulcerative colitis (pre-malignant lesions), but not in the hyperplastic polyps, ischemic colitis and quiescent ulcerative colitis (non-malignant diseases).
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PMID:[Mucin core peptide expression in malignant and non-malignant colorectal tissues]. 132 1

Immunohistochemical staining and histochemical approach for mucin were applied in studying 58 cases of colorectal adenomas. Among them, there were 13 cases of multiple adenomas (polyps), 5 cases of inflammatory polyps and 5 cases of juvenile polyps. The results indicated that positive expression of both McAb MC5 and Ulex europaeus agglutinin-1(UEA-1) were correlating with the degree of dysplasia, the histological type and the size of adenomas. The positive expression of peanut agglutinin (PNA) was correlating with the degree of dysplasia. Moderate and heavy stainings were mainly seen in adenomas accompanying with moderate and severe dysplasia, as well as adenomas with early carcinomatous changes. PAT-KOH-PAS method could sensitively reflect the occurrence of dysplasia and malignancy of the adenomas. These findings support the concept of an adenoma(dysplasia)-carcinoma sequence. In comparing multiple adenomas (number of adenomas > 100) with the solitary ones, a notable difference was obtained in the expression of McAb MC5. It's concluded that combined use of certain immunohistochemical and histochemical stainings is well be useful in detecting the malignant potentiality of adenoma.
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PMID:[Immunohistochemical and histochemical study on colorectal adenomas and polyps]. 133 45

Numerous nerve fibers containing various neuropeptides are found in gastric mucosa. They play an important role not only in regulation of gastric secretion, motility and microcirculation but also in regeneration and differentiation of gastric mucosa. These nerve fibers are reduced in chronic atrophic gastritis which is considered a lesion closely related to carcinogenesis. We investigated the effect of gastric gastric mucosal denervation (vagotomy) on gastric carcinogenesis by using two experimental rat models in which chronic atrophic gastritis is induced by duodenogastric reflux. At first, following administration of MNNG, vagotomy with duodenogastric reflux enhanced gastric carcinogenesis compared to reflux only. At second, in the model of gastric remnant in which no carcinogenic agent was given, both B-I and B-II gastrectomy with vagotomy showed an increase of carcinoma and/or adenoma at the anastomotic site compared to those without vagotomy. Moreover, in vagotomized groups, there were an increase of labeling index of PCNA positive cells in gastric mucosa and a marked reduction of intramucosal neutral mucin in PAS-Alcian blue staining. These results indicate that the lack of gastric mucosal innervation not only induces the decrease of gastric mucosal cell function and cytoprotection but also enhances the increase of immature cell regeneration.
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PMID:[Effect of gastric mucosal denervation on gastric carcinogenesis]. 136 55

The colorectal adenoma-carcinoma sequence was examined in relation to the ectopic expression of the oncofoetal Small Intestinal Mucin Antigen (SIMA), to the development of morphologic changes in the adenoma and perineoplastic mucosa and to indices of malignant potential. Four anti-SIMA MAbs, which define a novel hierarchy of SIMA epitopes in the normal small intestine and adjacent to colorectal cancers, were used in a retrospective immunohistochemical study of Familial Adenomatous Polyposis (FAP, n = 183) and non-familial (n = 44) adenomas. Inappropriate expression of SIMA epitopes was first detected in mucosa adjacent to minute microadenomas larger than three glands, and with increase in size, in increasing amounts within adenomas themselves, but not with microadenomas smaller than three glands or regions of flat mucosa free of adenomas. SIMA epitope expressed in mucosa adjacent to adenomas preceded changes in perineoplastic morphology, which progressed with adenoma growth to resemble transitional mucosa (TM) adjacent to cancers. Thus, the onset of both SIMA expression and morphological changes in TM were consistent with reactive rather than pre-existing field change phenomena. The previously reported hierarchy of four SIMA epitopes (5C5, 3D4, 4D3, 6C5) was also consistently observed in the adenoma-carcinoma sequence, and applied to (i) the order of epitope detection, (ii) the number of positive adenomas and (iii) extent of staining; (iv) the height in the crypt and (v) distance from the adenoma to which epitopes were expressed in perineoplastic mucosa. These observations are consistent with a progression of changes in mucin composition with adenoma development. The percentage of positive adenomas and reactivity scores for each anti-SIMA MAb correlated with increasing adenoma size, degree of dysplasia and growth pattern. SIMA expression appears to predate the earliest reported oncogene and tumour suppressor gene changes, was persistent and increased throughout adenoma development. SIMA epitopes are thus markers of very early neoplastic change, whose expression correlates with malignant potential and may contribute to the accumulation of changes necessary for tumourigenesis.
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PMID:The adenoma-carcinoma sequence in the colorectum--early appearance of a hierarchy of small intestinal mucin antigen (SIMA) epitopes and correlation with malignant potential. 141 17

Two new human epithelial cell lines from sporadic colorectal adenomas designated S/RR and S/BR are reported. Both cell lines have extended growth capacities in vitro, reaching passages 38 and 40 respectively and show no sign of senescence. S/RR and S/BR cell lines have retained the ability to differentiate in vitro, as shown by mucin production from goblet-like cells. S/BR was derived from a large colonic tubular villous adenoma (3 to 4 cm), whereas S/RR was derived from a small rectal adenoma (< 1 cm), and may represent a relatively early-stage adenoma. The parent S/RR cell line has given rise to a clonogenic variant, designated S/RR/Cl, which also has shown no sign of senescence and has currently reached passage 43. Both the S/BR and the S/RR cell lines had mutations in codon 12 of the K-ras gene, while retaining one normal allele. The presence of this mutation, particularly in the cell line S/RR derived from a small adenoma, is consistent with ras mutation being a relatively early event in colorectal carcinogenesis and is perhaps involved in the ability of the adenoma cells to progress and to give rise to an immortal cell line in vitro. The clonal derivatives of the S/RR cells have an isochromosome 1q and abnormalities of chromosome 13 which include an isochromosome 13q. The S/BR cells have a deletion on the short arm of chromosome 1 and trisomy 7. The common abnormality for S/RR and S/BR cells involves chromosome 1. The involvement of different chromosomes in the 2 cell lines also suggests different pathways for malignant progression of the premalignant adenoma cells.
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PMID:Specific cytogenetic abnormalities and k-ras mutation in two new human colorectal-adenoma-derived cell lines. 142 33

Progressive unilateral sensorineural deafness and tinnitus developed in a 59-year-old woman over a 1-year period. Clinical examination showed a tumor mass which almost completely filled the tympanic cavity, and grew around the auditory ossicular chain. Histological findings revealed the tumor to be a primary carcinoid of the middle ear. Neuro-endocrine differentiation was confirmed immunohistochemically by positivity for neuron-specific enolase, chromogranin, pancreatic polypeptide and synaptophysin. Using electron microscopy, neuroendocrine granules could be visualized. In addition, both light and electron microscopy revealed that cells had an epithelial differentiation with mucin granules while immunohistochemistry showed a positivity for cytokeratins. The detection of intermediary filaments (immunohistochemically with vimentin and under electron microscopy) was unique to this neoplasm and has to be considered in distinguishing the carcinoid tumor from the papillary adenoma of the middle ear. Tumor prognosis is excellent with radical extirpation from the middle ear. In the case presented, there has been no evidence for either recurrence or metastases 10 months after surgical resection.
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PMID:[Carcinoid of the middle ear: a rare tumor with biphasic differentiation. Case report with special reference to immunohistochemistry and electron microscopy]. 142 31

The term biologic marker (biomarker) of colorectal cancer refers in this article to an early preclinical phenotypic characteristic that relates to the risk for developing this cancer. Putative biologic markers in the normal colorectal mucosa of patients at risk include abnormal cell proliferation as determined by kinetic studies, ornithine decarboxylase activity, and polyamine synthesis. Alterations of mucin synthesis have been studied using both histochemical stains and lectin-binding techniques. Blood group and related carbohydrate antigens also have been evaluated as potential biomarkers in the normal mucosa. Biopsy small (less than 5 mm) polyps encountered at endoscopy has become a standard practice. Although a small polyp found to be an adenoma has a low likelihood of harboring high-grade dysplasia or invasive carcinoma, it represents an indicator of risk for colorectal neoplasia. Hyperplastic polyps, however, even though they have certain epidemiologic associations with colorectal neoplasia, are controversial as putative biomarkers of clinical relevance. Current research supports a concept of a field defect of the colorectal mucosa at risk for neoplasia, which may be identified by phenotypic abnormalities of the normal mucosa and the development of small adenomas.
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PMID:Precursors of colorectal carcinoma. Biopsy and biologic markers. 151 79

A 68-year-old woman with papillary adenoma of the pancreas with excessive mucin secretion is reported. The patient was initially diagnosed as having chronic pancreatitis because of a history of repeated attacks of pancreatitis and localized dilatation of the main pancreatic duct. Four years later, endoscopic retrograde pancreatography showed markedly diffuse dilatation of the entire main pancreatic duct with amorphous filling defects of mucin. Excretion of mucin was observed through the enlarged orifice of Vater's ampulla. The patient was treated with distal pancreatectomy, and papillary adenoma with abundant mucin in the cytoplasm was histologically demonstrated. We describe unique clinical features of "mucin-producing pancreatic tumor" and discuss an important role of endoscopic retrograde pancreatography in the diagnosis.
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PMID:Papillary adenoma of the pancreas with excessive mucin secretion. 155 39


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