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

Intranuclear cytoplasmic inclusions have been described previously in both human and animal tissue. So far as we are aware they are described in detail for the first time in this paper in 60 cases of malignant melanoma of the iris, usually in spindle cells. The light microscopic appearances are described, and electron microscopic studies of selected cases show clearly the genesis of these inclusions by cytoplasmic invagination of the nuclear membrane. Their significance is discussed. It is of interest that we have seen identical inclusions in malignant melanomas of the ciliary body, choroid, and conjunctiva but have not as yet reported our findings.
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PMID:Tumours of the anterior uvea. II. Intranuclear cytoplasmic inclusions in malignant melanoma of the iris. 624 99

The ultrastructure of conjunctival melanocytic lesions in 49 patients was evaluated to find significant differences between benign and malignant cells. The patients studied included 9 with benign epithelial (racial) melanosis, 2 with pigmented squamous cell papillomas, 16 with conjunctival nevi, 18 with primary acquired melanosis, and 11 with invasive nodules of malignant melanoma. In benign epithelial melanosis, dendritic melanocytes were situated along the basement membrane region of the conjunctival epithelium, with one basilar dendritic melanocyte lodged among every five or six basilar keratinocytes. The dendritic melanocytes extended arborizing cellular processes between the basilar and among the suprabasilar keratinocytes, which manifested considerable uptake of melanin granules into their cytoplasm. The benign dendritic melanocytes possessed nuclei with clumped heterochromatin at the nuclear membrane, small, tightly wound nucleoli, and large, elongated, fully melaninized melanin granules. In two patients with benign hyperplasia of the dendritic melanocytes, occasional dendritic melanocytes were located in a suprabasilar position, but were always separated from each other by keratinocytes or their processes. In the two black patients with benign pigmented squamous papillomas, the benign dendritic melanocytes were located hapharzardly at all levels of the acanthotic epithelium and not just along the basement membrane region. Melanin uptake by the proliferating keratinocytes was minimal. In benign melanocytic nevi of the conjunctiva, nevus cells within the intraepithelial junctional nests displayed a more rounded cellular configuration; short villi and broader cellular processes suggestive of abortive dendrites were found. The nuclear chromatin pattern was clumped at the nuclear membrane, but the nucleoli were somewhat larger than those of benign dendritic melanocytes in epithelial melanosis. The melanosomes were smaller and rounder than those in dendritic melanocytes and exhibited more haphazard arrangements of the melanofilaments, which were only partially melaninized. Mitochondria were more numerous than in dendritic melanocytes, and monoribosomes predominated over polyribosomes. Cytoplasmic filaments were inconspicuous. Cells in the immediate subepithelial connective tissue zone had features identical to those of the cells within the junctional nests. Smaller, lymphocytoid cells with less numerous and more rudimentary melanosomes were found in the middle and deeper portions of the lesions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The ultrastructure of conjunctival melanocytic tumors. 639 36

An immunohistochemical investigation regarding the presence of S-100 protein in benign and malignant, primary and metastatic melanocytic tumors is reported. The studied series consisted of 15 benign nevi, 3 blue nevi, 4 juvenile melanomas, 1 balloon cell nevus, 30 primary malignant melanomas of skin, mucous membranes and conjunctiva and 30 metastatic malignant melanomas. The immunohistochemical analysis showed positive staining for S-100 protein within the majority of the tumor cells in all benign tumors examined, except the balloon cell nevus, as well as in all the primary and metastatic malignant melanomas, including low-differentiated epitheloid or spindle-cell types without demonstrable melanin pigment. The results indicate that S-100 protein is a valuable marker for melanocytic tumors, especially in the fairly frequent dilemma of malignant melanoma presenting as a solitary non-pigmented metastasis of uncharacteristic light-microscopic appearance, and without known primary tumor. A characterization and quantification of the S-100 protein immunoreactivity in 5 metastatic malignant melanomas is presented. Using immuno-electrophoresis, the presence of 3 antigenic S-100 determinants was demonstrated within homogenates from the malignant melanomas, including the previously characterized S-100 A (alpha/beta) and S-100 B (beta/beta), and suggesting the presence of a hitherto undescribed variant of S-100 protein, possibly consisting of 2 alpha-subunits. Using rocket immuno-electrophoresis, the amount of S-100 protein was estimated.
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PMID:S-100 protein in melanocytic tumors. An immunohistochemical investigation of benign and malignant melanocytic tumors and metastases of malignant melanoma and a characterization of the antigen in comparison to human brain. 649 75

A 68-year-old white female with lentigo malignans of the right conjunctiva and lid developed recurrent malignant melanomas of the conjunctiva 16 years after, lesions were treated by local excision and cryotherapy on several occasions. The prognosis of the three different histologic types of malignant melanoma described by Clark: nodular melanoma, superficial spreading melanoma, and lentigo malignans melanoma is discussed. Histologic features associated with the height of the tumor are important factors for prognosis, patients with lentigo malignans melanoma appearing to have a better systemic prognosis than those with superficial spreading or nodular melanoma. Possible therapeutic approaches to this condition are exenteration of the orbit, excision combined with cryotherapy, and excision combined with radiotherapy. The advantages of each of these treatments, and their indications, are discussed.
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PMID:[Malignant melanoma of the conjunctiva arising from precancerous melanosis, prognosis and treatment]. 663 Aug 90

The authors experienced one case of malignant melanoma of the superior palpebral conjunctiva and the inferior palpebral skin, originating from benign acquired melanosis of the bulbar conjunctiva which developed in a 48-year-old man. Orbital exenteration including superior and inferior palpebrae was performed, and the removed tissue was examined by light and electron microscopy. In the temporal bulbar conjunctiva, melanocytes containing abundant fine melanin granules proliferated over almost the whole area of the epithelial layer. Cellular atypia and karyomitosis were not observed. The basement membrane remained intact with no proliferation of melanocytes in the substantia propria. However, in the perivascular area, in addition to the moderately prominent infiltration by lymphocytes and plasma cells, infiltration by melanophages was observed relatively frequently. Based on these findings, it was confirmed that the primary lesion of the bulbar conjunctiva was an acquired melanosis of Stage IB as classified by Zimmerman. The black nodular tumors of the superior palpebral conjunctiva and inferior palpebral skin consisted of melanoma cells showing markedly prominent cellular and nuclear atypia. The nuclei showed indentations in the membrane with electron-lucent karyoplasm, each having one nucleolus. The cytoplasm contained many round or elongated melanosomes in various developmental stages, with sizes of about 0.7 micron. Scattered among melanoma cells were a number of melanophages which had phagocytized many melanosomes at various stages of maturity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Light and electron microscopic studies of malignant melanoma of conjunctiva and palpebra. 665 10

Administration of a hematoporphyrin derivative (HpD) followed by photoradiation with red light completely or partially destroyed Greene hamster melanoma developed in the anterior chamber of rabbit eyes. Tumor-bearing eyes were divided into two groups. Twenty-two eyes received an HpD injection followed by exposure to red light from a slide projector with a 500-W quartz halogen lamp and a red filter (intensity to the tumor was about 4.0 mW/sq cm). In the control group (six eyes), eyes were exposed either to red light only or to HpD injection only. Local complications after therapy included edema and congestion of the conjunctiva, clouding of the cornea, and hemorrhage on the iris surface. The HpD itself has no cytotoxic effect, is preferentially retained in tumor cells, and causes a destructive photodynamic effect as a result of the production of cytotoxic singlet oxygen in the tumor. Accordingly, it may be a safe and potentially therapeutic procedure in the treatment of uveal melanoma.
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PMID:Hematoporphyrin phototherapy for experimental intraocular malignant melanoma. 686 Feb 2

Papanicolaou smear cytology is a simple diagnostic procedure for the evaluation and management of external ocular lesions. A variety of benign and neoplastic lesions are examined for correlation of clinical, cytologic, and histologic impressions. Accurate correlation in 38 of 41 eyes substantiates the reliability of Papanicolaou smear cytology to differentiate benign from neoplastic ocular lesions. Cytology proved useful in the preoperative evaluation of squamous cell carcinoma and related tumors of the conjunctiva, and malignant melanoma of the conjunctiva. Cytology also was valuable in the detection of tumor recurrence in squamous cell carcinoma and carcinoma-in-situ of the conjunctiva, and in Meibomian gland carcinoma of the eyelid. The accessibility of ocular tumors makes them particularly well suited for cytologic examination.
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PMID:Papanicolaou cytology in the diagnosis and management of external ocular tumors. 699 Sep 6

Conjunctival melanomas are much less common than custaneous melanomas. Consequently, the classification and treatment of these mucosal tumors is more controversial than that of skin tumors. Conjunctival melanomas can be simply classified into tumors that are superficial and develop in a radial-growth phase, and those that are invasive and develop in a vertical-growth phase. By careful histological examination the maximum tumor thickness can be measured and the presence of the tumor within conjunctival epithelium, the substantia propria, or deeper tissues can be determined. Superficial tumors, tumors with a total radial-growth phase, tumors thinner than 0.76 mm., tumors confined to the conjunctival epithelium, and tumors near the corneal limbus seem to have a favorable prognosis. The fact that a conjunctival melanoma arises in an area of acquired melanosis, arises in association with a nevus, or arises de novo has not been definitely proved to be of prognostic significance. Treatment of conjunctival melanomas should be preceded by biopsy and histological confirmation of the diagnosis. Systemic evaluation should include examination of regional lymph nodes, chest roentgenograms, liver scans, and liver function tests. The eye and the complete conjunctival surface should be carefully examined, photographed, and drawn. The commonly accepted treatment of stage I melanomas of the skin or conjunctiva is surgical removal of the malignant tissue. Superficial and minimally invasive tumors near the corneal limbus may sometimes be excised with en bloc resection of the adjacent superficial cornea and sclera. Treatment of any malignant tumor must be somewhat individualized. Melanomas involving the fornices and eyelids may be treated by complete excision or by exenteration. Exenteration seems to be a reasonable plan in patients with extensive or bulky tumors. The role of prophylactic regional node dissection has not been established for patients with conjunctival melanomas. Similarly, adjunctive chemotherapy, immunotherapy, and hormone therapy are of unknown value in the management of stage I tumors of the conjunctiva. Cryotherapy and radiation therapy have been used only in small numbers of patients with conjunctival melanomas. The choice of these treatments instead of surgical excision in the management of such tumors should be highly selective.
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PMID:Melanomas of the conjunctiva. 699 85

Long-term prognosis was analyzed by a retrospective study of 56 patients with malignant melanoma of the conjunctiva and the eyelids. Survival rate at 5 years was 85 p. cent, at 10 years 68 p. cent, and at 15 or 20 years 55 p. cent; neither the localization of the tumor nor the type of initial treatment had a significant influence on these rates. Local or nodal recurrences occurred in 80 p. cent of cases, and were frequent following conservative surgery; prognosis is bad after radiotherapy.
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PMID:[Malignant melanoma of the conjunctiva and eyelids: analysis of prognosis in 56 cases (author's transl)]. 709 94

Case report of a metastatic carcinoma of the conjunctiva originating in a cutaneous superficial spreading melanoma. Conjunctival metastasis as well as dissemination of skin melanomas to the eye are extremely rare events. As to our knowledge until now, there is not documentation of a cutaneous malignant melanoma metastatic to the conjunctiva.
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PMID:[Metastatic conjunctival tumor originating in a primary cutaneous malignant melanoma (author's transl)]. 709 46


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