Multiple intracranial malignant melanoma metastasis: report of one case with review of literature

Abstract

Objective To explore the clinicopathological and immunohistochemical features of intracranial malignant melanoma metastasis. Methods Analysed the clinical features, histopathologic findings and immunohistochemical staining in 2 lesions of one case with multiple intracranial malignant melanoma metastasis, and studied the diagnosis and differentiation of this disease with literature review. Results The pathologic findings of the 2 lesions located in the right frontal lobe and right temporal lobe were dissimilar to each other. The previous lesion presented as old hematoma was composed of a few papilliform structures within sheet of bleeding with capillaries and fibrous tissue surrounded by epithelioid cells. The following lesion in the right temporal lobe was predominantly composed of spindle cells with rich cytoplasm, marked nuclear atypia and eosinophile nucleoli that arranged in cell nests and fascicles. Brisk mitotic activity and necrosis could also be seen in the tumor. Left inguinal lymph nodes metastasis notable with thick melan in granule inside and outside the tumor cells was found, and the tumor cells were similar to those of the lesion in the right temporal lobe. Immunohistochemistry with antibodies for S-100 protein (S-100), HMB45, Melan-A, vimentin (Vim), epithelial membrane antigen (EMA), cytokeratin (CK), glial fibrillary acidic protein (GFAP), synaptophysin (Syn) and neurofilament protein (NF) was performed. A diffuse reactivity of the neoplastic cells for S-100 protein, HMB45, Melan-A, vimentin was observed. EMA presented partially positive. All other markers were negative. Conclusion The histopathologic findings of intracranial malignant melanoma metastasis are quite complicated. Although the clinical case history and neuroimaging are important, the diagnosis of the disease is dependent on immunohistochemical staining method. It must be differentiated from metastatic carcinomas, meningeal tumors, malignant lymphomas and other melanocytic neoplasms.

DOI:10.3969/j.issn.1672-6731.2011.04.018