Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence of nervous tissue specific S100 protein was studied immunohistochemically in 47 cases of malignant melanoma and 25 pigmented nevi of various types of peroxidase-antiperoxidase immunoenzyme method on routine paraffin sections of the surgical specimens. Of 47 cases of malignant melanoma, 44 were positively stained for S100 protein. The intensity of S100 protein immunostaining was suggested to be inversely proportional to the amount of melanin pigment. In ten cases of 12 amelanotic melanomas, the immunoreaction for S100 protein in tumor cells was stronger than that of normal Bergmann glial cell in human cerebellum. Intradermal nevi and juvenile melanomas were strongly positive for S100 protein, but blue nevi contained little or no S100 protein. Our results suggest that S100 protein is widely distributed among melanotic tumors and is also a very useful diagnostic indicator for malignant melanoma, especially of the amelanotic type.
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PMID:Immunohistochemical demonstration of S100 protein in malignant melanoma and pigmented nevus, and its diagnostic application. 680 28

Malignant fibrous histiocytoma was diagnosed in seven cats from biopsy specimens received at the University of Missouri Veterinary Medical Diagnostic Laboratory during a 4-year period from 1987-1991. Tissue blocks from formalin-fixed specimens were resectioned and stained for type I (AE1) and type II (AE3) cytokeratins, desmin, S100 protein, vimentin, and alpha 1-antitrypsin by the avidin biotin peroxidase complex method with diaminobenzidine (DAB) chromogen. None of the tumors stained positively for alpha 1-antitrypsin. Four of seven of the tumors had similar immunohistochemical staining results, with positive staining for type I and type II cytokeratins, desmin, S100 protein, and vimentin. Of the remaining three, one stained positively only for S100 protein and vimentin; one stained positively for vimentin only; and one was negative for all six antigens. Based only on immunohistochemical staining results, three of the tumors could possibly be reclassified: one as a melanoma, one as a probable fibrosarcoma, and one as unknown. These results also indicate that feline malignant fibrous histiocytomas show a diversity of intermediate filament expression, as do human tumors. Our results also do not support the theory that malignant fibrous histiocytomas are of histiocytic origin.
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PMID:Immunohistochemical staining of feline malignant fibrous histiocytomas. 751 36

Immunohistochemical demonstration of S100 protein was performed in 56 cases of malignant melanoma of the facial skin and oral cavity. The depth of invasion was measured comparatively in HE sections and in sections stained for S100 protein. Comparison of measured melanoma invasion depth in S100- and HE-stained sections revealed a deeper invasion of the tumor in S100-stained slides than in slides stained routinely with HE according to Breslow's melanoma staging procedure. A reverse relationship between the intensity of immunohistochemical staining for S100 protein and survival rate was found in both melanomas of the facial skin and oral cavity. Although the presence of S100 protein has been demonstrated previously in skin melanomas, no similar investigations concerning the oral mucosa have been performed up to now.
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PMID:Immunohistochemical demonstration of S100 protein in malignant melanomas of the facial skin and oral cavity. 752 13

Cytokeratin (CK) positivity has been considered a specific marker for epithelial differentiation in cytologic specimens. After observing CK reactivity in fine-needle aspirate (FNA) specimens of melanoma and sarcoma, a retrospective study of melanomas and sarcomas was undertaken to investigate the frequency of anomalous CK staining in these neoplasms. Cell block sections and/or restained smears from 36 melanomas and sarcomas were retrospectively stained for CK. An appropriate internal positive control (HMB-45), S100 protein, or vimentin) was also used to insure antigen preservation. Of the smears from 19 melanomas, five revealed focal strong CK positivity of neoplastic cells, two cases showed faint or equivocal staining, 11 cases were negative for CK, and one could not be interpreted due to inadequate controls. Of the smears from 14 sarcomas, two showed positivity for CK (one fibrosarcoma and one condrosarcoma), 11 were negative, and one had inadequate controls. The number of CK positive cells was less than that observed with the appropriate internal positive control antibodies. Destained Papanicolaou smears were superior to Diff-Quik smears for retrospective immunocytochemical stains. Cell block sections from four of the melanomas and one sarcoma demonstrated no aberrant staining. Since cytokeratin positivity occasionally is seen in nonepithelial neoplasms, its presence alone cannot be used to make a definitive diagnosis of carcinoma. Therefore, a panel of immunocytochemical stains should be utilized in diagnosis of FNA specimens.
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PMID:Cytokeratin positivity in fine-needle aspirates of melanomas and sarcomas. 873 62

Nine cases of primary oral mucosal melanoma in Caucasian patients were reviewed and the tumours analysed for expression of S100, HMB45, NKI/C3, HLA-DR, PCNA, cytokeratin and von Willebrand factor. The clinical, histopathological and immunohistochemical features were quite distinctive and our findings support previous suggestions that oral melanoma should be classified as a separate entity rather than as a sub-type of cutaneous melanoma.
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PMID:A clinicopathological and immunohistochemical analysis of primary oral mucosal melanoma. 763 81

The clinical significance of serum S100 was assessed in comparison to neuron-specific enolase (NSE) in 126 patients with malignant melanoma: 80 patients with clinical stage I/II, 23 patients with stage III and 23 patients with stage IV according to the criteria of the American Joint Committee on Cancer (AJCC). Using cut-off values of 0.15 micrograms/l for S100 and 12.5 micrograms/l for NSE, the sensitivity was found to be 1.3% (1/80) for S100 and 8.75% (7/80) for NSE in patients with stage I/II, 8.7% (2/23) for S100 and 13% (8/23) for NSE in patients with stage III, and 73.9% (17/23) for S100 and 34.8% (8/23) for NSE in patients with stage IV disease (P < 0.05). In 6 patients with stage III/IV tumours, serial measurement of serum S100 and NSE was performed. A rise of serum S100 indicated progression of the disease; a decline indicated response to treatment. Our preliminary results support the value of serum S100 as an adjunct to the clinical staging and monitoring of metastatic malignant melanoma.
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PMID:Clinical significance of serum S100 in metastatic malignant melanoma. 854 Nov 29

We evaluated three cases of pigmented pulmonary carcinoid tumors that were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Clinical follow-up showed no indication of tumor recurrence or metastases, nor was there evidence of malignant melanoma. All three cases exhibited histologic features of typical carcinoid tumor; there were focal oncocytic changes in two cases. Finely dispersed, brown pigment, believed to be melanin, was distributed in two different patterns: in sustentacular cells (case 1) or within the tumor cells (cases 2 and 3). Fontana-Masson stain was positive in areas of this pigment in all cases. The tumor cells showed immunoreactivity for chromogranin, synaptophysin, keratin (AE1/AE3 and CAM-5.2), and S100 protein in all cases. Focal staining for vimentin and corticotropin was seen within neoplastic cells in two cases. The pigmented sustentacular cells in case 1 showed focal immunoreactivity for S100 protein and HMB-45. Ultrastructural studies of paraffin-embedded tissues were performed in two cases. They showed well-developed melanosomes in the pigmented sustentacular cells in case 1. In both cases, cytoplasmic neurosecretory-type granules were identified in neoplastic cells. These findings demonstrate that pigmented pulmonary carcinoid tumor has an immunohistochemical profile similar to that of typical pulmonary carcinoid tumor. In some instances, pigmented pulmonary carcinoid tumors may show ultrastructural evidence of melanocytic and neuroendocrine differentiation. These immunohistologic and ultrastructural findings distinguish pigmented pulmonary carcinoid tumor from malignant melanoma and support the concept of "multidirectional cellular differentiation."
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PMID:Pigmented pulmonary carcinoid tumor. An immunohistochemical and ultrastructural study. 768 14

Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM on the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasize readily.
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PMID:Desmoplastic malignant melanoma presenting with orbital involvement. 791 65

The authors propose the addition of malignant melanoma to the list of extrarenal neoplasms that may be predominantly composed of polygonal cells with the cytologic features of "rhabdoid" tumor. A review of 313 metastatic melanomas disclosed 49 examples with rhabdoid features, from which 31 had sufficient material for further pathologic and immunohistologic characterization. A control group of 46 nonrhabdoid metastatic melanomas was examined in parallel fashion. In 39% of cases, rhabdoid melanomas manifested relative deletion of S100 protein compared with the control tumors. However, there were no differences in staining with HMB-45. Vimentin immunoreactivity was concentrated in the paranuclear cytoplasm of rhabdoid melanoma cells. However, ultrastructural studies of these cases failed to show corresponding whorls of intermediate filaments and instead demonstrated paracrystalline paranuclear inclusions in profiles of rough endoplasmic reticulum. It is concluded that metastatic rhabdoid melanoma exhibits significant morphologic similarity to other rhabdoid tumors at a light-microscopic level. However, it usually retains enough melanocytic attributes to allow for accurate diagnostic recognition. Probably because patients with metastatic melanoma have an extremely poor prognosis overall, no worsening of biologic behavior was associated with rhabdoid cytomorphologic findings in this tumor type when compared with the control cases.
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PMID:Metastatic malignant melanoma with "rhabdoid" features. 778 65

Melanotic neuroectodermal tumors of infancy (MNTI) are uncommon, usually benign neoplasms, most frequently found in the maxilla. These tumors are extremely rare in the epididymis. Only 18 cases with this site of origin are documented. We report on the third epididymal MNTI with some morphological characteristics of malignancy but favorable clinical outcome. The 2 cm large tumor of a 6-month-old male infant showed large epitheloid cells in the center and small neuroblastoma-like cells at the periphery. Despite invasion of lymphatics there is no evidence of relapse or metastases during 4 years of follow-up. Immunohistochemically, the large tumor cells were distinctly positive for cytokeratin, vimentin, GFAP, the melanoma marker NKI-C3, NSE, and S100. The small tumor cells were only slightly positive for GFAP, NKI-C3, NSE, and S100 but they were negative for cytokeratin and vimentin. Neurofilament and chromogranin could not be proved in the tumor.
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PMID:Melanotic neuroectodermal tumor of infancy (MNTI) in the epididymis. A case report with immunohistological studies and special consideration of malignant features. 794 25


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