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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pigmented tumors of the eyelid are often difficult to identify accurately, as different tumors may have the same clinical presentation. We report the case of a 84 year old female patient who noticed a black tumor of the lower eyelid, with a recent increase in size. Clinically, this lesion was an exophytic tumor of the medial part of the left lower eyelid, respecting the lacrimal punctum and involving the palpebral margin. A surgical excision was performed. Microscopic examination revealed a pigmented seborrheic keratosis, a benign tumor of the epidermis. Histopathology has a key role in the precise diagnosis of pigmented tumors of the eyelid, in which the differential diagnosis concludes sweat gland cysts, pigmented basal cell carcinoma, naevus and uncommon malignant melanoma.
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PMID:[Pigmented seborrheic wart on the skin of the eyelid]. 129 78

Twenty-one intradermal nevi were studied by morphometric methods in an attempt to morphologically characterize the two types of nevus cell--epithelioids, type A, and fusiforms, type C--and to quantify the differences between them. Morphometric parameters of the intradermal nevi were compared with similar parameters of melanocytes and melanoma cells so that the maturation rates of the nevi cells could be established and to see if the parameters might indicate the degree of malignancy. Superficial nevus cells were differentiated from deep cells by their larger size and larger nuclear area. Nuclear area appeared to have potential for differentiating benign from malignant tumors. Decrease in cellular area appeared to indicate maturation rather than atrophy. Melanoma cells were differentiated by their larger size. Cell nuclear perimeter appeared to have confirmatory value, while cell perimeter was inconclusive.
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PMID:Application of morphometric methods to the cytologic study of intradermal nevi. 129 28

A follow-up study of 113 patients with suspicious iris nevi who were referred to our clinic between 1973 and 1991 was carried out by: reviewing their clinical records, fluorescein angiography, obtaining recent data with cooperation of their own or the referring ophthalmologist and contacting patients for reexamination. After examination the diagnoses were: 64 suspicious nevi, 23 melanomas, 15 ciliary body tumors with iris involvement and 11 other pseudomelanomas. In the group of suspicious nevi 86% was localized in the inferior part and 66% in the temporal part of the iris; for the melanoma group these figures were 78% and 75% respectively. The chamber angle was more often involved in the melanoma group, 40% against 17% in the suspicious nevi group. In this group 11 cases (21.6%) showed growth during the follow-up (mean 10.6 years). In three cases the tumor was surgically removed, with as histopathologic diagnosis: 1 xanthogranuloma, 1 neurolemmoma and 1 possible melanoma. In the melanoma group 16 lesions (76%) showed growth during the follow-up (mean 7.2 years), in most cases within 5 years of the initial diagnosis. The lesion was surgically removed in 11 cases. The histopathologic diagnoses were: 8 melanomas, 1 xanthogranuloma, 1 possible melanoma and 1 metastasis of a skin melanoma. Our study shows that periodic ophthalmic check-ups are of great importance in the management of iris lesions suspect for melanoma.
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PMID:Iris nevi and melanomas: a clinical follow-up study. 130 27

The cellular proto-oncogene, ras, is known to play an important role in the regulation of cell growth and proliferation in normal and malignant conditions. The present study was undertaken to immunohistochemically examine the expression of ras protooncogene product p21 in normal human skin and some cutaneous tumours. In normal skin, the expression of p21 was found in sweat glands, sebaceous glands, capillary endothelium, and smooth muscles, while epidermis was devoid of reaction product. Keratoacanthoma and the granular cells of verruca vulgaris were immunoreactive to the antibody for p21. Bowen's disease and squamous cell carcinoma were positive for p21, but basal cell carcinoma and seborrheic keratosis were negative. In mammary and extramammary Paget's diseases, the immunoreactivity was inconsistent. The expression of p21 in malignant melanoma cells was intense, whereas normal melanocytes and nevus cells were devoid of the expression. These results suggest that the expression of p21 does not correlate with nuclear anaplasia and malignant behaviour of cutaneous tumours.
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PMID:Expression of ras proto-oncogene related protein p21 in normal human skin and cutaneous tumours. 132 35

Regardless of subsequent clinical courses of patients with dysplastic nevi (DN), substantial evidence supporting DN as one of the melanoma-prone diseases is not yet available, especially in sporadic DN, due to the lack of genetic information other than retrospective studies in clinical observation. This study aimed at the immunohistological characterization of sporadic DN distinct from common nevi (CN) and at the evaluation of the potentially of sporadic DN for malignant transformation. We considered our results together with previous immunological and epidemiological reports. We noted the following three immunohistological characteristics. 1) Proliferating cell nuclear antigen (PCNA), one of the markers for active cell division, could be detected on DN cells in junctional nests of only one among ten DN examined but not on CN cells at all. 2) The altered expression of alpha-smooth muscle actin (alpha-Sma), often observed in melanoma cells, could not be detected in DN cells. However, anti-alpha-Sma monoclonal antibody (MoAb) clearly demonstrated distinctive hypervascularity in the stroma surrounding DN when compared with CN. 3) ME491 antigen, which is known to be expressed mainly in the radial growth phase of melanoma, was detected with similar intensity on both DN and CN. These data indicate that DN has a somewhat higher potentiality than CN for cell division and secretion of some cytokines which can induce hypervascularity in the surrounding stroma, but that DN has not yet undergone the significant phenotypic changes observed in melanoma cells. Further advancements in understanding molecular events in DN cells will be of great benefit in setting DN in the multiple oncogenic spectrum from pigment cells to melanoma.
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PMID:Dysplastic nevus syndrome: melanoma-prone disease. 136 25

To evaluate the proliferative activity of benign, borderline and malignant cutaneous melanocytic neoplasms, 30 cases of malignant melanoma (MM) and 41 cases of naevi were studied by immunostaining using a monoclonal antibody against proliferating cell nuclear antigen (PCNA). PCNA is a nuclear antigen expressed in the late G1 and S phase and serves as a marker of proliferating cells. Invasive MM and MM in situ showed much higher PCNA positivity rates than melanocytic naevi (invasive MM, 18.0%; MM in situ, 11.3%; ordinary melanocytic naevi, 2.6%). The PCNA positivity rate did not increase significantly with the thickness of MM. Among ordinary melanocytic naevi, junctional naevi had a higher PCNA positivity rate than compound or intradermal naevi. Mean PCNA positivity rates for Spitz's naevi and sporadic dysplastic naevi were within the range for ordinary melanocytic naevi, indicating the benign nature of both types of naevus. Contrary to some previous studies, MM in situ showed high proliferative activity, indicating that cells of MM in situ are actively proliferating. This study clearly demonstrates that MM and various types of naevi can be separated according to differences in proliferative activity defined by the PCNA labeling index.
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PMID:Proliferative activity of cutaneous melanocytic neoplasms defined by a proliferating cell nuclear antigen labelling index. 136 60

Although most examples of cutaneous malignant melanoma are easily recognized by their clinical appearances, in some cases this serious neoplasm may clinically simulate other less serious forms of skin cancer or benign processes. This study was undertaken to assess both the sensitivity of clinical diagnosis of cutaneous malignant melanoma and the efficacy of biopsies of clinically unsuspected melanomas in yielding specimens on which complete and accurate histologic assessments could be made. A retrospective analysis of 1784 cases of histologically proven melanomas diagnosed between 1985 and 1990 was performed in search of lesions not clinically suspected. Biopsy techniques used to sample these lesions were subjected to critique of their efficacy in yielding specimens that could be accurately diagnosed and completely assessed histologically. Of 1784 histologically proven primary cutaneous melanomas, 583 were not clinically suspected, yielding a sensitivity of 67%. Clinical diagnosis included nevi (33%), no diagnosis (17%), multiple diagnoses (13%), basal cell carcinoma (12%), keratosis (9%), and lentigo (9%) among others. The biopsy methods used to sample these lesions were shave (56%), excisional (24%), punch (11%), curettage (2%), and undetermined (6%). Eighty-six percent of shave biopsies could be accurately assessed while only 32% of punches and no curettages provided sufficient material for both definitive and complete evaluation of melanomas. Eighteen percent of specimens histologically reviewed were considered inadequate for complete evaluation. In 34%, the actual diagnosis of melanoma was uncertain because of inability to assess diagnostic features as a consequence of the biopsy technique. Melanoma may be unsuspected clinically in a significant number of cases and may be mistaken for less serious cutaneous neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sensitivity of diagnosis of malignant melanoma: a clinicopathologic study with a critical assessment of biopsy techniques. 136 17

A 7-month-old boy had a giant pigmented lesion involving the trunk and thighs that exhibited many hyperpigmented hairy and verrucous nevi. One of the nevi ulcerated and on histological examination consisted of pleomorphic rhabdomyosarcoma cells that stained for muscle-specific actin (HHF-35), desmin, and myoglobin. Around the tumor, in the dermis, benign pigmented nevus cells were observed. The occurrence of malignant tumors, other than malignant melanoma, in pigmented nevi is rarely described.
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PMID:Rhabdomyosarcoma in a congenital pigmented nevus. 137 40

Whereas the inflammatory infiltrates of malignant melanoma have been widely investigated, little is known about the infiltrates accompanying benign melanocytic naevi. Using monoclonal antibodies directed against HLA-DR antigens, the CD1 antigen, the transferrin receptor and functionally divergent macrophage subpopulations, frozen fresh material of 87 melanocytic naevi (MN), ten primary cutaneous melanomas (PCM) and ten samples of normal skin were studied. Compared with normal skin, abundant HLA-DR+ cells were found in the stroma of MN equivalent to the quantity present in PCM. In MN we found higher numbers of dermal CD1+ dendritic cells compared with PCM and normal skin. There were more macrophages that expressed the transferrin receptor or the antigens 27E10, RM3/1 and 25F9 in MN than in normal skin but fewer than in PCM. No significant differences were found between congenital MN (n = 40), common acquired MN (n = 27) and dysplastic MN (n = 20) macrophage subpopulations. Also, no correlations were evident between macrophage infiltrates and naevus location or patients' age. Our data show that potential melanoma precursors among melanocytic naevi cannot be identified by the pattern of macrophage infiltrates.
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PMID:Macrophages in melanocytic naevi. 138 Feb 30

The combined naevus is made up of two components, one resembling a melanocytic naevus, the other a blue naevus. Clinically, these naevi do not give any obvious cause for concern. Histological examination shows that the combined naevus consists of a superficial melanocytic naevus and a deep-seated spindle cell blue naevus. There is a rare variant in which the pigmented spindle cells of the "blue" naevus are replaced by large balloon cells varying in melanin content. These combined naevi, because of the large cells with abundant cytoplasm, closely resemble malignant melanoma. As a further aid to diagnosis we used the monoclonal antibody HMB 45. In our study, the vesicular cells in all seven combined naevi examined reacted strongly with HMB 45. It is suggested that HMB 45 is not always helpful in differentiating between melanoma and naevi.
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PMID:[HMB 45 positive balloon cells in combined nevi]. 139 2


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