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

The histologic distinction between craniopharyngioma and epidermoid is equivocal. Eight craniopharyngiomas and ten epidermoids (including three dermoids) as well as nine rat (Wistar) abdominal skins that acted as control were investigated by a silver colloid method for nucleolar organizer regions (Ag-NORs). The mean number of Ag-NORs in at least 200 cells of both basal (columnar) epithelial cells and suprabasal (prickle) cells was evaluated. It was found that the mean number of Ag-NORs in basal cells of epidermoid and rat skin was significantly greater than that in suprabasal cells (P < 0.001 in nine of ten epidermoids and in all rat skins). On the other hand, of eight craniopharyngiomas, the mean Ag-NOR number in basal cells was not significantly different from that in suprabasal cells in five cases, and, further, the former was significantly smaller than the latter in the other three cases (P < 0.01 in two and P < 0.05 in one). These findings suggest that a stepwise maturation of the epithelial cells like that in mammalian skin epidermis exists in epidermoids but not in craniopharyngiomas. In craniopharyngiomas, the maturation of the epithelial cells seems to be considerably limited or lost from the aspect of proliferative potential as assessed by Ag-NOR score, which indicates neoplastic growth of craniopharyngiomas. Ag-NOR staining may thus be a useful method to distinguish craniopharyngioma from epidermoid.
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PMID:Proliferative assessment of craniopharyngioma and epidermoid by nucleolar organizer region staining. 128 54

Numerous data concerning nucleolar organizer region (NOR) structure and function in normal and pathological human cells are analysed. The contents of argentophilic nucleolar proteins vary in the cells tested. The silver-stained test is closely connected with cellular proliferative potentials and differentiation status of the cells. This test also depends on the level of tumor cell malignancy and seemed to be very useful for megakaryocyte and cardiomyocyte studies. In summary, the NOR silver-staining approach is of great value for both fundamental cytological investigations and wide medical practice.
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PMID:[The structure and function of the chromosomal nucleolus organizer regions: the molecular, cytological and clinical aspects]. 129 71

Silver-stained nucleolar organizer regions (AgNORs) in human breast carcinoma were studied using a computer-assisted system of image analysis. Standardized, automatic measurements of 7 morphometric parameters (area, perimeter, shape factor, bend energy, angle, and small and large diameters) performed on paraffin sections and cell imprint were compared and correlated with nuclear morphometry, histopathological grading, tumor growth fraction, (monoclonal Ki67-immunostaining), DNA nuclear content (stoechiometric Feulgen staining) and axillary lymph node invasion. The major findings were as follows: (i) variations in AgNORs and nuclear parameters were correlated, (ii) the ratio of AgNOR area/nuclear area was significantly different in low and high grade tumors, (iii) mean AgNOR parameter values increased significantly with the tumor growth fraction and tumor hyperploidy and were significantly higher in patients with axillary lymph node metastases and (iv) AgNOR evaluation was more accurate for cell preparations than for tissue sections.
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PMID:Correlation of nucleolar organizer regions and nuclear morphometry assessed by automatic image analysis in breast cancer with aneuploidy, K167 immunostaining, histopathologic grade and lymph node involvement. 130 May 97

To study the distribution and thromboembolic effect of Ultrafluid Lipiodol, 15 surgically removed hepatocellular carcinomas with selective intraarterial Lipiodol injection 7 to 10 days before surgery and 15 noninjected controls were studied radiologically and histologically. Tissue blocks were processed with an en bloc silver impregnation technique for Lipiodol localization in histologic sections. Lipiodol was distributed evenly in tumors measuring less than 5 cm in diameter and peripherally in tumors measuring 10 cm or more. Lipiodol droplets were mainly extracellular. There was no difference in tumor architecture or in hemorrhage and necrosis scores between Lipiodol-injected cases and negative controls (1.18 versus 0.92). Similarly, in injected cases, no differences were observed between Lipiodol-positive and Lipiodol-negative areas (scores of x-ray Lipiodol-positive versus Lipiodol-negative areas: 1.17 versus 1.36; scores of microscopic Lipiodol-positive versus Lipiodol-negative areas: 1.18 versus 1.14). Lipiodol-negative but hypodense areas examined by x-ray proved to be necrosis or fibrosis with or without viable tumor islands. Lipiodol has no thromboembolic effects. The uneven Lipiodol distribution may account for its failure as a carrier for chemotherapeutic agents in large tumors.
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PMID:Distribution of Lipiodol and evidence for tumor necrosis in hepatocellular carcinoma. 131

Argyrophilic nucleolar organizer regions (AgNOR) have been correlated with proliferative activity of neoplasms. Increased AgNOR may reflect increased proliferative activity of cells or ploidy. To explore this hypothesis, 41 breast carcinomas were processed for AgNOR silver staining and DNA flow cytometry. AgNOR counts were expressed as mean AgNOR/nucleus and percentage of tumor cells with more than five AgNOR/nucleus. The first count was designated mean AgNOR or mAgNOR, and the second count was designated AgNOR proliferative index or pAgNOR. Using Mantel-Haensel statistical analysis, carcinomas that exhibited mAgNOR of 2.4 or more had a high likelihood of aneuploidy (P less than 0.0001), an S-phase fraction of more than 5.8% (P less than 0.003), or a diameter greater than 2 cm (P less than 0.007). In addition, tumors with pAgNOR of 8% or more showed a statistically significant correlation with aneuploidy (P less than 0.004), tumor grade (P less than 0.04), and a more significant one with high S-phase fraction (P less than 0.0001). No significant correlation was obtained between pAgNOR and tumor size or lymph node status. These data indicate that AgNOR quantitation reflects changes in DNA ploidy and cell proliferation. They also suggest that the mean AgNOR counts correlate best with the DNA mass or ploidy and that the frequency of cells with higher AgNOR count best reflects proliferative activity or S-phase fraction.
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PMID:Argyrophilic nucleolar organizer regions in breast carcinoma. Correlation with DNA flow cytometry, histopathology, and lymph node status. 131 92

AgNOR staining technique was applied to facilitate the pathologic differential diagnosis of 74 breast tumors and 95 non-Hodgkin's lymphoma (NHL). The results showed that the mean AgNOR count per nucleus was significantly different between benign and malignant tumors (P less than 0.01). An AgNOR count per cell less than 3 indicated benign breast lesion and more than 5 implied malignancy. In NHL, AgNOR count that nucleolus less than 4 was indicative of low-grade while more than 6 of high-grade malignancy. In 45 NHL patients followed up, the AgNOR count/cell was high in 28 patients with short survivals than otherwise (17 patients). These observations suggest that the AgNOR could provide useful information about the nucleolus activity in hyperplastic and neoplastic conditions. Electron microscopically, argyrophilic protein was irregular in shape and highly stained with silver in the fibrillar centers and the dense fibrillar component in NHL tumor cells as compared to that seen in normal lymphocytes. This further implies that the NOR Proteins could be used as a marker of ribosomal DNA and its level of transcription is higher in the malignant tumors.
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PMID:[AgNOR in the pathologic differential diagnosis of tumors]. 131 72

A heterogenous mostly neuroendocrine small cell carcinoma was found in a gallbladder resected from a 75-year-old man suffering from CLL. It progressed along bile ducts into choledochus, into omentum and liver. Its histology was characterized by solid alveoli and small cell trabeculae with a high mitotic activity, dissociated infiltration in some parts and desmoplasia. Sometimes a typical adenocarcinomatous differentiation could be found out. Tumour cells produced immunohistological expression of EMA, CEA, NSE and CHG and had Grimelius silver impregnation positivity. Neuroendocrine gallbladder carcinomas used to be more aggressive than carcinomas of another type, can cause an endocrine syndrome and claim a special treatment.
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PMID:[Heterogeneous carcinoma of the gallbladder with neuroendocrine differentiation]. 132 Oct 5

A review of 78 renal tumors in patients under 6 months of age revealed 35 congenital mesoblastic nephromas (CMNs). Based on cellular criteria, 14 were classified as classical, 4 as partly cellular, and 17 as cellular CMN. The mean ages were 24, 11, and 70 days, respectively. There were 13 intrarenal tumors (stage I) but 9 classical, 3 partly cellular, and 5 cellular CMNs extended to the perirenal fat (stage II) and 5 cellular tumors ruptured (stage III). In order to assess cellular proliferative activity, silver staining of nucleolar organizer region (Ag-NOR) proteins was performed on 19 CMNs. The number of Ag-NOR dots per cell was significantly lower in classical and partly cellular CMN than in cellular CMN, whatever the stage (P < .01). Within the cellular CMNs, the mean number of Ag-NOR dots was statistically higher in the single case that recurred with fatal outcome (P < .02). Counting of Ag-NOR dots appears to be a reproducible method for evaluating the biologic potential of CMNs. The number of Ag-NOR dots, DNA content measurements, the histological subclassification, and the presence or absence of tumor at the surgical margins may be useful features in selecting those patients who will benefit from further treatment after nephrectomy.
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PMID:Nucleolar organizer regions in congenital mesoblastic nephroma. 133 74

We conducted a trial in 42 benign and malignant meningiomas to assess a possible influence of preoperative dexamethasone therapy on mitotic index, labelling indices of proliferating cell nuclear antigen (PCNA), progesterone receptor, epidermal growth factor receptor (EGF-R), c-erbB-2 oncoprotein, cathepsin D, gamma-gamma enolase as well as the mean number of silver-stained nucleolar organizer region-associated proteins (AgNORs). Tumors with preceding dexamethasone therapy for more than 1 day display significantly less immunohistochemical staining for PCNA. A correlation between the labelling index of PCNA and the degree of malignancy could not be identified. There was no significant effect of preoperative dexamethasone therapy on the other parameters. Our data suggest that dexamethasone may selectively inhibit the expression of PCNA in the G1/S-phase of the cell cycle. Thus, we emphasize the necessity to heed factors, e.g. dexamethasone, which may affect the expression of proliferating markers.
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PMID:Influence of preoperative dexamethasone therapy on proliferating cell nuclear antigen (PCNA) expression in comparison to other parameters in meningiomas. 136 Aug 48

Because it is not easy to determine the tumor status of meningiomas by current diagnostic procedures, we investigated these tumors immunohistochemically using the monoclonal antibody PC 10. This antibody recognizes a fixation- and processing-resistant epitope of the proliferating cell nuclear antigen (PCNA), which is a 36-KD nuclear antigen associated with the cell cycle. We studied paraffin-embedded and formalin-fixed tissue specimens of a group of 21 atypical/malignant meningiomas together with 18 benign meningiomas. PCNA staining results were compared with the mean number of silver-stained nucleolar organizer region-associated proteins (AgNORs), tumor grading, and mitotic indices of these tumors. The percentage of PCNA-positive cells was found to range between 0.1% and 40%, irrespective of the tumor grade. When all tumors were collectively considered, no positive correlation was found between PCNA scores and histologic grading and only a weak one between PCNA score and mitotic index. A higher correlation was seen between AgNOR counts and tumor grading. Our results suggest that PCNA labeling and histologic grading seem to be independent parameters. The correlations found between AgNOR counts and tumor grading should be substantiated in further series.
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PMID:Proliferating cell nuclear antigen (PCNA) in atypical and malignant meningiomas. 136 64


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