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)

Six cases of malignant melanoma in children 14 years of age and younger are reported. The six cases were diagnosed among 850,000 consecutive skin biopsy specimens and consultation slides examined within a 32-year period. This series included an infant born with neurocutaneous melanosis, a child with malignant melanoma developing in a large congenital nevus at the age of 13 years, a superficial spreading malignant melanoma, Clark Level III, in a child with many dysplastic nevi, and three cases with primary nodular malignant melanoma, two of which showed histologic features of Spitz nevus. A review of the literature indicates that malignant melanoma in childhood is rare, and no large series have been investigated. It is not known whether the genetic and the environmental factors incriminated in the development of malignant melanoma in adults play a role in childhood melanomas. Data on the incidence of childhood melanoma in the population, the clinical and the histologic variations, and the prognosis are not adequate. A multiinstitutional study is needed to gather a large enough series to provide this information.
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PMID:Malignant melanoma in childhood. 850 75

Nevus with cyst is characterized by a melanocytic nevus that is closely associated anatomically with an epidermoid cyst. We describe the clinicopathologic manifestations of 93 cases (from 92 individuals) observed during a 6-year period and review the features of the 69 previously reported nevi with cysts in the world literature. It is important for both clinicians and pathologists to recognize this common benign condition because growth of these lesions is frequently misinterpreted by the patient as representing either a new melanoma or malignant transformation of a preexisting lesion. Variants of nevus with cyst include lesions in which the nevus is a congenital, "dysplastic," blue, or Spitz nevus. The cysts may be steatocystomas, hidrocystomas, dermoid, or trichilemmal cysts. In some cases, folliculitis may be present within the nevus instead of a true cyst.
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PMID:Nevus with cyst. A report of 93 cases. 780 73

We saw a patient with a Spitz nevus surrounded by a halo of depigmentation. Although the halo phenomenon is often seen in pigmented melanocytic nevus, an association of this phenomenon with Spitz nevus seems to be rare. Moreover, histopathological findings showed focal lymphoid infiltration in the epidermis of the depigmented halo and marked infiltration in dermal epithelioid nevus cell nests. Thus, it is suggested that identical mechanisms are involved in the destruction of epidermal melanocytes and dermal nevus cells in halo Spitz nevus.
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PMID:Histopathological evaluation of halo phenomenon in Spitz nevus. 859 54

Peripherin is an intermediate filament involved in growth and development of the peripheral nervous system and is localized to neurons, some other cells derived from neural tube and neural crest, and some neuroendocrine cells (e.g. beta cells of islets of Langerhans). Peripherin also has been demonstrated in neuroblastomas and cutaneous neuroendocrine (Merkel cell) carcinomas. The expression of peripherin by other cells derived from the neural crest is unknown. We evaluated by immunohistochemistry 74 cutaneous melanocytic lesions including primary invasive malignant melanoma (IMM), melanoma in situ (MIS), atypical nevus (nevus with architectural disorder and cytologic atypia of melanocytes) (AN), spindle and epithelioid cell nevus (Spitz nevus) (SN), blue nevus (BN), and common intradermal benign melanocytic nevus (BMN) for expression of peripherin. Peripherin was detected in a cytoplasmic distribution within tumor cells in 14/14 IMM and 8/10 MIS. For IMM, peripherin localized to both the intraepidermal and invasive dermal components. Peripherin was detected in 10/10 AN and 9/9 SN, being localized to the intraepidermal component and, focally, to the superficial dermal component of the lesions. The dendritic nevus cells in 15/15 BN also expressed peripherin. For most of the BMN, expression of peripherin was absent or limited to rare, scattered cells in the superficial portion of the lesions. Melanocytes in adjacent normal skin were not labeled in any of the lesions studied. These results indicate that expression of peripherin is common in both benign and malignant melanocytic lesions, but not in normal resting adult melanocytes. Among benign lesions, expression of peripherin in the dermal component is rare except in the dendritic cells of BN. These findings provide evidence that the expression of peripherin, a marker of neuronal differentiation, is maintained by IMM, MIS, and BN, but is lost in the normal maturational sequence of the dermal component of other melanocytic lesions.
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PMID:The intermediate filament peripherin is expressed in cutaneous melanocytic lesions. 908 49

The current classification of malignant melanomas gives recognition to superficial spreading melanoma, lentigo maligna melanoma, acral lentiginous melanoma, and nodular types. In addition, neurotropic and desmoplastic types are recognized. The relativity inherent in the diagnosis of melanoma, provides the basis for the classification of melanomas on the basis of size. Lesions measuring 1 mm or less in vertical dimensions are unlikely to metastasize; they qualify as borderline melanocytic neoplasia of indeterminant malignant potential. The current classification has little relevancy to the category of variant nevi with the exceptions of malignant cellular blue nevus and melanoma arising in giant congenital nevi. A classification of variant melanomas as related to variant nevi is proposed. From a different perspective, a classification of melanomas with attention to nesting and cytological patterns in vertical growth is proposed: this alternate approach gives recognition to lesions that might otherwise be classified as "nevoid" melanomas. It also provides a default category for lesions that might otherwise be assigned to the Spitz nevus-like category. All of these tools for the manipulation of the real and virtual images of melanomas have been emphasized in the concept of minimal deviation melanoma.
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PMID:Variants of melanoma. 922 May 53

In this study, we demonstrate that immunostaining with MIB-1 and anti-bcl-2 is a useful tool to distinguish compound Spitz nevi from malignant melanomas. Forty-six cases of Spitz nevi and 50 cases of vertical growth-phase melanomas (Clark III-V) were compared for the immunoreactivity of MIB-1 and bcl-2 in the intradermal component of the lesions. As many as 76% of the Spitz nevus cases showed a low percentage (0-2%) of MIB-1 immunoreactivity. In the malignant melanomas, such a low MIB-1 index was shown in only 2% of the cases. The average MIB-1 index in malignant melanomas and Spitz nevi was 29.7 and 4.0%, respectively. bcl-2 was negative in only 4% of the melanoma cases, whereas the corresponding value was 72% in Spitz nevi. Statistical analyses using Students t test showed that the differences were highly significant (P < 0.001). By considering the immunoreactivity for MIB-1 and bcl-2 in the individual cases, we found that as many as 96% of the melanomas both expressed a bcl-2 positivity and exhibited a MIB-1 index exceeding 2% in the dermal component. The corresponding value was as low as 6% in the Spitz nevi.
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PMID:Immunohistochemical markers for distinguishing Spitz nevi from malignant melanomas. 931 Sep 55

One hundred and three cases of Spitz nevi were reviewed, 36% of these patients were adults. The lesions in children occurred primarily on the face and secondarily on the trunk followed by the extremities. In adults, they affect the legs in women, and the trunk in men as does malignant melanoma. Clinically they were diagnosed more frequently as Spitz nevi in children and adolescents than in adults. Spitz nevi were most commonly mistaken clinically for "common" melanocytic nevus, hemangioma, verruca, fibrous histiocytoma, molluscum contagiosum, granuloma pyogenicum, keloid, and melanoma. Histologically, there are various expressions of Spitz nevi, but they are usually compound melanocytic nevi with little pigmentation and typically large spindle- and/or epithelioid melanocytes. There are only small histopathological differences between Spitz nevi in childhood and adulthood: one important feature rarely seen in Spitz nevi of adults is multiple mitotic figures at the dermo-epidermal junction but rarely at the base of the melanocytic nevus. Nevus Reed is considered to possibly be a distinctly pigmented variant of Spitz nevus.
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PMID:[Spitz nevus and Reed nevus: simulating melanoma in adults]. 988 3

Impaired regulation of apoptosis is known to be associated with the development of various forms of cancer. Fas binding to its ligand, Fas ligand (Fas-L), has been shown to trigger apoptosis in various cell types. Fas-L is expressed by melanoma cells and has been suggested to play a role in melanoma escape from immune surveillance. In the present study, we assessed apoptotic activity and examined Fas and Fas-L expression in malignant melanomas, Spitz nevi and ordinary melanocytic nevi. We evaluated apoptotic activity using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling. Apoptotic activity was found to be minimal in melanomas and moderate in Spitz nevi. In contrast, common nevi demonstrated significant levels of apoptosis in the deep parts of the tumor. Fas was found to be expressed by all Spitz nevi, most melanocytic nevi and approximately half of the malignant melanoma specimens. Fas expression was also significantly more pronounced in Spitz nevus cells as compared with the two other tumors. The anti-Fas-L antibody was found to stain all three melanocytic tumors. Staining was shown to be stronger and more frequent in melanoma cells as compared to the nevus cells. Using the Spearman test, no significant correlation between Fas-L expression in melanoma cells and apoptosis in MM-infiltrating mononuclear cells was found, suggesting that Fas-L expression in melanoma cells may not be instrumental in their ability to escape immune mechanisms of defense. In contrast, increased levels of apoptosis in the deep parts of melanocytic nevi may reflect and possibly contribute to their benign nature.
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PMID:Apoptosis, Fas and Fas-ligand expression in melanocytic tumors. 1008 96

Benign melanocytic naevi exhibit a wide spectrum of histological appearances. Some share significant clinical and histological features and are recognized as entities. Included among these are pagetoid/junctional Spitz naevus, pigmented spindle cell naevus, halo naevus, recurrent and traumatized naevus, ultraviolet (UV) irradiated naevus, naevus in infants, acral naevus, genital naevus and naevi from other specific anatomic locations. However, there still remains a diagnostic grey area of acquired predominantly junctional naevi with architectural and cytological atypia. Only a small percentage of these will fulfil the criteria for dysplastic naevus if criteria are strictly applied. Therefore, there exists a group of otherwise ordinary acquired naevi with atypical junctional activity, mostly mild, whose biological significance is unclear. In older individuals, although junctional activity in otherwise benign naevi does occur, extra care should be exercised in order to prevent the diagnosis of melanoma in situ being overlooked.
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PMID:Benign atypical naevi: diagnostic difficulties and continued controversy. 1021 58

The morphologic distinction between Spitz nevus and malignant melanoma can be difficult. Because cyclin D1 has been reported to be overexpressed in malignant melanomas, but not in common acquired nevi, we hypothesized that cyclin D1 might be a useful marker to distinguish Spitz nevi from malignant melanoma. Thus, we assessed for cyclin D1 expression in 11 Spitz nevi (10 compound and 1 intradermal) and 9 malignant melanomas (4 Clark stages I-III and 5 Clark stages IV-V) using an immunohistochemical method and routinely fixed and processed tissues. The cyclin D1 results were arbitrarily divided into three groups: 0% to 10%, >10% to 25%, and >25%. We confirmed the observations reported previously by others that cyclin D1 is expressed in malignant melanomas but not in common acquired nevi. Unexpectedly, a relatively high number of cyclin D1-positive cells (i.e., >10%) was also found in all cases of Spitz nevus. However, unlike malignant melanoma, the cyclin D1 positivity in Spitz nevi was present in a zonal pattern. In other words, the number of cyclin D1-positive cells decreased as the lesion extended more deeply, with the number of positive cells in the reticular dermis being less than that in the papillary dermis. Fluorescence in situ hybridization methods were used to assess amplification of 11q13, the locus harboring the cyclin D1 gene, in four cases of Spitz nevus; all were disomic. Using the antibody MIB-1, we compared cyclin D1 expression to the proliferation rate in Spitz nevi. Despite the high cyclin D1 positivity, all Spitz nevi had a relatively low number of MIB-1-positive cells (mean=3.2%), which was significantly lower than that of malignant melanomas (mean=15.3%) (p < 0.001). Thus, unlike malignant melanoma, there appears to be a dissociation between cyclin D1 overexpression and cell proliferation in Spitz nevi.
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PMID:Cyclin D1 overexpression in Spitz nevi: an immunohistochemical study. 1021 69


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