Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nine lymph nodes with so-called benign nevus cell nevi were studied by light microscopy. In three cases the lymph nodes were also examined by electron microscopy. The solitary or multiple cell clusters were 35-645 mu in diameter and were usually found in the lymph node capsule or cortex. They were more frequent in the older patients. There was no predisposition for either sex. Specific morphologic features allowing clear cytologic identification of the cells were not evidient. In particular, there was no indication that they represented nevus cells. However, they showed a great morphologic similarity to glomus cells. In addition, they were usually found near blood vessels. We assume that the cell clusters were hamartias related to glomangiomas. We call them glomus cell clusters.
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PMID:[Glomus cell clusters of the lymph node]. 18 48

From 1950 through 1974, 37 cases of hydatidiform mole not followed by malignancy and 11 cases of invasively growing trophoblastic tumors (IGTT) occurred among indigenous Greenlandic women. The overall incidence of benign mole was 1:850 births, only slightly higher than most incidences in low-risk areas like Western Europe, North America, Australia, and Israel. In contrast, the overall incidence of IGTT, 1:2861 births, and the minimum incidence of histologically confirmed choriocarcinoma, 1:5245 births, are among the highest population-based incidence on record. A marked increase in incidence of both hydatidiform mole and IGTT was found late in reproductive life. A recent high incidence of mole among teenagers increased the incidence with statistical significance during the latest 10 years, whereas maximum incidence of IGTT was found in 1960--64. A strong association existed between hydatidiform mole and IGTT. During the study period Greenlandic women with mole had a 20% risk of developing IGTT and 64% of IGTT cases were preceded by molar pregnancy. Four cases of benign mole, but no case of IGTT, occurred among the small group of Danish women living in Greeland. The incidence, 1 mole:685 births, was higher than among the indigenous population, although the latter had a lower socio-economic status. The reason for the high occurrence of IGTT among indigenous Greenlanders remains unknown. The predominating HL-A 9 antigen could conceivably reflect a genetic predisposition.
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PMID:Trophoblastic tumors in Greenland. 23 Jan 89

A chorioretinal granuloma that contained acid-fast bacilli and a choriodal nevus that consisted of benign nevus cells yielded false-positive radioactive phosphorus tests. The beta emission exceeded that of the control areas by more than 100% in each case. The granuloma had infiltrated the sclera, permitting inflammatory tissue to be in closer proximity to the counting probe than was the normal choroid. The reason for the increased metabolic activity of the nevus cells remains unexplained.
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PMID:False-positive results with the radioactive phosphorus test. 58 12

Melanotic lesions of the mucosal membranes of the head and neck have been reported infrequently. Malignant melanomas are reported with much more frequency than benign nevi in this region. The first reported case of a nevus of the middle ear mucosa is presented. The distinctions between this lesion, nevus of Ota, meningioma, Schwannoma, and hematoma are discussed. The malignant potential for this lesion is not known, but it appears low enough to obviate interval tympanotomy.
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PMID:Pigmented lesion of the middle ear: report of a case. 93 65

Previous studies have demonstrated a specific cytoplasmic fluorescence in human melanocytes, as well as in pigmented nevi and in malignant melanomas, when the formaldehyde histofluorescence method for visualization of certain catechol and indole derivatives was used. In malignant melanoma two fluorogenic substances, dopa and cysteinyldopa, were found previously. In human melanocytes and benign nevi cells the fluorogenic catechols have so far not been characterized, since chemical analyses are difficult to perform on skin, due to the small amounts of catechols present. However, using split thickness skin quantitative determinations are possible by sensitive fluorometric methods. The chemical analyses of cysteinyldopa showed that in human adult skin most or all was located in the superficial layers. The only specific fluorescence in the thin skin was found in dendritic melanocytes. The findings leave little doubt that cysteinyldopa is stored in melanocytes although the possibility of a concomitant occurrence of other thioethers is not excluded. Nevi and giant nevi were also similarly studied and we found considerable amounts of cysteinyldopa in the nevi. It seems as if the cysteinyldopa is stored in the fluorescent nevi cells. There was no consistent difference in the content of the catechol derivatives between intradermal and compound nevi.
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PMID:On the occurrence of cysteinyldopa and dopa in melanocytes and benign nevi cells. 105 47

In 21 patients with a variety of skin tumors (squamous cell carcinomas, malignant melanomas, basal cell epitheliomas and mycosis fungoides) or pre-cancerous lesions (Bowen's disease, actinic keratosis, junctional nevus cell nevus) the radioactive phosphorus uptake test demonstrates a significantly increased concentration of P32 in those tumors. There were no false negative tests. The possibility of differentiation of malignant melanoma from benign nevus cell nevus and the early recognition of cutaneous metastases is described. Furthermore recurrence of previously irradiated or excised basal cell epitheliomas can be detected without a biopsy. No hematological side-effects were observed.
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PMID:[The radiophosphorus (32P)-test in precanceroses and malignant tumors of the skin]. 127 Feb 58

Reflectance spectrophotometry from 420 to 780 nm on 31 primary melanoma and 31 benign nevi has been performed by using an external integrating sphere coupled to a spectrophotometer. Measurements show that reflectance spectra of melanoma and nevi manifest dissimilar patterns. From these spectra four variables, whose physical and/or physiological meanings remain to be investigated, have been derived. All of them are significantly different when compared between melanoma and nevi. A discriminant function between the two groups of lesions has been determined by using a stepwise discriminant analysis, resulting in a test with a sensitivity of 90.3% and a specificity of 77.4%. This method of discrimination between melanoma and nevi seems to have a discriminating power almost equal to that of a clinical judgement from a specialized medical doctor, thus suggesting a new method for screening skin pigmented lesions.
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PMID:In vivo spectrophotometric evaluation of neoplastic and non-neoplastic skin pigmented lesions. II: Discriminant analysis between nevus and melanoma. 162 Jul 28

Silver staining of nucleolar organizer regions is an objective method for evaluating the malignancy of a variety of tumors. We studied 126 ciliochoroidal melanomas, three coincidental nevi that occurred in eyes with melanomas, and one magnocellular nevus collected from the Collaborative Ocular Melanoma Study to determine the effectiveness of the silver-stained nucleolar organizer region technique in assessing the malignant potential of these tumors. Malignant lesions demonstrated higher mean silver-stained nucleolar organizer region counts (4.347) than benign nevi (1.855) (P less than or equal to .0001). Among malignant melanomas, mixed-cell melanomas had slightly higher counts than spindle-cell melanomas (P less than or equal to .0001), but this difference was not important clinically. Results were also compared to other histopathologic variables, which disclosed correlation of silver-stained nucleolar organizer regions with mitoses and tumor size. Comparison with computerized cytomorphometric analyses of prognosis also disclosed significant correlation. This technique may prove to be a useful adjunct in the assessment of malignancy and treatment response of uveal melanomas.
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PMID:The value of nucleolar organizer regions in uveal melanoma. The Collaborative Ocular Melanoma Study Group. 170 Jun 11

Antigen expression was studied by immunohistochemistry in 133 human melanocytic skin lesions to gain insight into the initial steps of tumor development, i.e. in particular the change from melanocytes to benign nevi. We refer to the proposed progression model of Clark and co-workers. The following types of antigens were investigated: (i) intermediate filament antigens (vimentin), (ii) melanoma-associated antigens (HMB-45, NKI/C3, MA-930, LS59), (iii) proliferation-associated antigens (S-100, Ki67, Ro/SSA, calmodulin), (iv) progression-associated antigens (HLA-DR, ICAM-1), and (v) basal membrane antigens (bullous pemphigoid antigen, laminin, fibronectin, collagen type IV). The intensity of expression and the topography of immunoreactive pigment cells were compared with the stage of tumor progression. Special attention was paid to the early steps of this process, i.e. the disturbance of the epidermal melanin unit and the development of melanocytic ("nevocellular")nevi. A dramatic shift of antigen expression (antigen types [i] to [v]) was noted in benign nevi compared with melanocytes. Nevi with cellular atypia disclosed a tendency towards an increased percentage of tumor cells reactive for melanoma- and progression-related antigens (types [ii] and [iv]). However, there was no clear cut level of distinction of antigen expression (types [i] to [v]) between benign and primary malignant melanocytic tumors. So-called dysplastic nevi resembled benign tumors or melanocytes rather than malignant melanoma. Metastatic melanoma of skin showed a relatively high number of Ki67-positive, cycling melanoma cells. The results have a bearing on the concepts of melanocytic nevus ontogenesis and "maturation". It appears that melanocytes lose maturity on their way down to the dermis in contrast to traditional concepts (Abtropfung); this might be of importance for our understanding of melanoma development in association with melanocytic nevi. Our findings are discussed with regard to Clark's model of tumor progression.
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PMID:The initial steps of tumor progression in melanocytic lineage: a histochemical approach. 174 97

Tumour cell proliferation and particularly tumour cell motility are considered to be essential pre-requisites for invasive tumour growth. Despite abundant in vitro data on tumour cell motility, the behaviour of tumour cells in complex human tumour tissues is yet unknown. In this study, estimates of proliferation and motility are statistically derived from morphological tumour patterns in human melanocytic skin tumours. Two-dimensional, discrete, random computer simulations of tumour growth were carried out in order to determine the influence of tumour cell proliferation and motility on morphological patterns. A set of binary morphological criteria turned out to facilitate a significant estimate of the relative probabilities of motility and proliferation (CART analysis). When the same morphological criteria were applied to H & E stained slides of 45 melanocytic skin tumours, benign common nevi showed a predominance of motility, whereas primary and metastatic malignant melanoma revealed a predominance of proliferation. The direct assessment of the number of proliferating cells by Ki-67 staining shows a steep increase from benign nevi to primary and metastatic melanoma. These data provide first evidence that in benign common nevi the overall motility exceeds the very low degree of proliferation, whereas in malignant melanocytic tumours proliferation considerably exceeds tumour cell motility.
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PMID:Computer simulation analysis of morphological patterns in human melanocytic skin tumours. 179 95


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