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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-three cases of congenital malignant melanoma have previously been reported. Here the authors report the first case of a congenital malignant melanoma arising in the eye. A newborn girl had a large pigmented ocular tumor, hepatomegaly, and multiple pigmented skin and choroidal lesions. The histopathologic diagnosis was of a malignant melanoma with hepatic metastases. The skin and choroidal lesions were considered to be congenital melanocytic nevi. The most plausible pathogenetic link between these two conditions was that the malignancy had arisen as a second-hit mutation within a choroidal congenital melanocytic nevus. Despite widespread metastases the baby, treated by surgery and chemotherapy, survives in good health, aged 2 years, 10 months.
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PMID:Congenital malignant melanoma of the eye. 201 65

The cytoskeleton is considered to be important for maintaining cell shape and facilitating cell movement. In the present study, the expression of cytoskeletal components is examined in benign and malignant melanocytic skin tumors. Paraffin sections of 75 cases (25 each of nevocellular nevus, primary malignant melanoma, and cutaneous metastases of malignant melanoma) were stained with antibodies to tubulin, myosin, actin, and vimentin using a three-step immunoperoxidase method. The staining results were assessed independently for tumor cells and stroma cells in comparison to inbuilt reference structures. Vimentin is found in all melanocytic lesions in the tumor as well as in the stroma cells. In malignant lesions, the tumor cell staining intensity varies between neighboring regions; particularly in malignant melanoma the staining is pronounced in the tumor periphery (chi 2 test: p less than 0.05). Actin is only weakly positive in nevus cells and primary melanoma tumor cells, but strongly expressed in metastatic tumor cells (p less than 0.001). Nevus fibroblasts are only weakly positive, whereas the stroma fibroblasts in the malignant lesions are strongly positive (p less than 0.001). The same is true for myosin and tubulin expression in dermal fibroblasts (p less than 0.001), whereas the tumor cells are equally (weakly) positive in all melanocytic lesions. Our study shows that there are significant differences in the immunohistochemical expression of cytoskeletal components in various melanocytic tumors. There is an elevated expression of vimentin and actin in the tumor cells, particularly of metastatic lesions. However, the most pronounced differences are found in the dermal fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of cytoskeletal components in melanocytic skin lesions. An immunohistochemical study. 202 88

Malignant melanoma is a well documented but rare occurrence in children. We reported a case of a 10-month-old girl with malignant melanoma arising in a giant congenital nevocellular nevus. A giant mole on the lumbar and gluteal legion had been present since birth. Six month later, a nodular legion within the giant nevus started to growth slightly. The skin nodule were widely excised and grafted. Histological examination showed a malignant melanoma. The tumor located only in dermis. An enlarged lymph node of her left inguinal was removed. The histology revealed metastases from the melanoma. She died of metastases eight months after removal of the primary tumor. To our knowledge, only 37 documented cases of malignant melanoma in children under fifteen years of age have been previously reported, to which we add our case. In Japan, two-thirds of childhood melanomas arise de novo, which are clinically and biologically analogous to adult melanomas. The other third arises in large congenital nevocellular nevus which likely lead to death within two to three years of diagnosis. A majority of at least half of malignant melanoma in large congenital nevocellular nervus arise in children under 10 years of age. ALM types of malignant melanoma which are common in adult are rare in childhood melanomas.
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PMID:[Malignant melanoma in children--case presentation and statistical analysis]. 220 21

Clinical and histopathological evidence suggests that melanoma develops in a sequence of steps, progressing from benign proliferative lesions, to primary melanomas that do not show evidence for metastasis, to invasive primary lesions, and to metastases. This review focuses on the experimental studies examining the phenotypic characteristics of cultured primary melanoma cells as they relate to cells from non-malignant nevi and metastases. Genetic, biologic, and immunologic criteria have been established to distinguish melanocytes from different steps of tumor development. These include non-random chromosomal abnormalities, expression of melanocyte- and melanoma-specific antigens, requirements for exogenous growth factors, production of endogenous growth factors, and expression of receptors for growth factors. The transformation of melanocytes and nevus cells with viral oncogenes has facilitated studies on the malignant phenotype. Variants have been developed through successive selections from primary melanoma cell populations that have one or several characteristics of metastatic cells. The study of melanocytes isolated from various stages of tumor development and the generation of cell variants with specific properties should enable a long-term search for the molecular mechanisms of melanoma development and progression.
Cancer Metastasis Rev 1990 Sep
PMID:Human melanoma: development and progression. 225 10

The authors examined 36 patients with melanoblastoma and 10 with pigmented nevus. The use of thermography for differential diagnosis of pigmented neoplasms, and as well for early diagnosis of melanoma recurrences and metastases is recommended.
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PMID:[Use of thermography in the differential diagnosis of pigmented neoplasms]. 239 82

Basement membranes found around tumor cells in nevocytic nevi, Spitz's nevi, and malignant melanomas were analyzed by electron microscopy and antibody staining for several basement membrane proteins. Nevocytic nevi and Spitz's nevi showed a distinct, occasionally discontinuous lamina densa regardless of whether they were located in junctional zones of the epidermis or within the dermis. All basement membranes around nests of aggregated nevus cells, however, lacked anchoring fibrils. This correlated with the absence of type VII collagen. In contrast, type IV collagen, laminin, and nidogen were present at the periphery of the nevus cell clusters in agreement with the presence of an intact lamina densa. Aggregated tumor cells in malignant melanomas were bordered by a lamina densa when located in a junctional position and lacked this structure when they had migrated into the dermis. This process was accompanied by a drastically reduced staining for collagen type IV and nidogen, whereas laminin was still detectable. Anchoring fibrils and their molecular correlate, type VII collagen, were consistently absent. These observations demonstrate major alterations in the composition of basement membranes around malignant melanomas, which can be an important factor for the invasive growth and formation of metastases of these tumors.
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PMID:Structure of basement membranes in malignant melanoma and nevocytic nevi. 249 91

Expression of beta 2 microglobulin (beta 2M), a light chain of class 1 HLA antigen, was studied in normal melanocytes and in benign and malignant melanocytic tumors by use of immunohistochemical methods. By immunoelectron microscopy, normal melanocytes were shown to express beta 2M on the cell surface. In lentigo maligna melanomas and acral lentiginous melanomas, the mean percentages of beta 2M-positive tumor cells were significantly lower in thick (greater than 1.50 mm) primary lesions and metastases than in thin (less than or equal to 1.50 mm) primary lesions. The evidence suggests that melanocyte-derived melanoma clones with a low grade of malignancy preserve class 1 HLA expression, and that the clones with a high grade of malignancy tend to lose the antigen expression. Nevus cells in common nevi have little or no expression of beta 2M. In halo nevi, however, beta 2M were detected on nevus cells in the lesions associated with inflammatory infiltration. Immunohistochemical analyses of the cellular composition of the inflammatory cells in halo nevi demonstrated the presence of cytotoxic T cells together with helper/inducer T cells, Langerhans cells, and macrophages. It appears that nevus cells of halo nevi are destroyed by cytotoxic T cells and that class 1 HLA antigens expressed on nevus cells play an important role in the target cell recognition and lysis by specific cytotoxic T cells.
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PMID:Beta 2 microglobulin expression in normal melanocytes, nevocellular nevi, and malignant melanomas. 265 98

We report on the clinical and pathologic features of 32 lesions diagnosed as malignant spindle cell and epithelioid cell nevus (S&E nevus). Because of the clinical or initial histopathologic diagnosis of malignant melanoma, six patients had lymph node dissection. Three of these patients also had an enlarged lymph node. In all six cases, metastatic spindle or epithelioid cells were found in at least one of the resected lymph nodes. Of the 30 patients with follow-up information, including all six patients with lymph node metastases, all are alive and well. No recurrences or further metastases have been found. On histopathologic reevaluation, all the lesions had features of S&E nevi. Study of these cases suggests that although some lesions with features of S&E nevi may involve local lymph nodes, widespread metastases do not result.
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PMID:Spindle cell and epithelioid cell nevi with atypia and metastasis (malignant Spitz nevus). 280 11

The unique curability of gestational trophoblastic tumors may in part be attributable to a host immunologic response. The occurrence of rapidly progressive and fatal choriocarcinoma may be favored by histocompatibility between patients and their partners. However, histocompatibility is not a prerequisite for the development and persistence of gestational choriocarcinoma. The expression of HLA by choriocarcinoma cells in culture is enhanced following incubation with gamma-interferon and this may be of both biologic and clinical significance. Complete molar pregnancy is a complete allograft because all molar chromosomes are of paternal origin. Patients with complete mole are sensitized to paternal HLA antigen which is expressed in molar tissue. Other polymorphic antigen systems including trophoblast-leukocyte common antigens and placental-type alkaline phosphatase are also expressed in molar tissue. We have studied the immunopathology of the molar implantation site to investigate possible humoral and cellular immune responses. The relationships among normal placenta, complete mole and choriocarcinoma are not clearly understood. The pattern of expression of oncofetal antigens in these three gestational tissues may be used to assess trophoblastic differentiation. In studies to date, molar trophoblast has the same pattern of expression of oncofetal antigens as normal placental trophoblast. We will review recent advances in our understanding of the immunobiology of gestational trophoblastic disease and suggest new directions for further research.
Cancer Metastasis Rev 1986
PMID:Immunobiology of complete molar pregnancy and gestational trophoblastic tumor. 303 May 77

We examined 2,227 lymph nodes from 100 patients with clinical Stage I cutaneous melanoma for the presence of microscopic deposits of tumor. On examination of hematoxylin-and-eosin-stained sections, none had melanoma. Sixteen nodes from 14 patients had melanoma detectable by an antiserum to S-100 protein in a peroxidase-antiperoxidase (PAP) assay. The melanomatous nature of these cells was confirmed by their reaction with the melanoma-directed monoclonal antibody NKl/C3. The incidence of occult nodal metastases was highest in patients with deeply invasive and micrometrically thick primary tumors. The incidence of occult melanoma was not increased where additional serial sections were cut and semiserial sections examined. Pitfalls in the identification of occult melanoma cells (OMC) include S-100 protein-positive interdigitating dendritic cells, capsular nevus cells, a minority of sinus "macrophages," and the Schwann cells of node-associated nerves. Thus, we conclude that the incidence of early melanoma metastases in the regional lymph nodes of patients with clinical Stage I melanoma is greater than has previously been appreciated on the basis of assessment of routine hematoxylin-and-eosin-stained sections. Six of the 14 patients with OMC died of melanoma (41%), as compared to only 18 of 86 patients without OMC (21%; 0.10 greater than P greater than 0.05).
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PMID:Occult tumor cells in the lymph nodes of patients with pathological stage I malignant melanoma. An immunohistological study. 271 94


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