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Xanthomatous meningioma is an extremely rare variant of meningioma that is characterized histopathologically by the presence of tumor cells with lipid-filled vacuolated cytoplasm. In this report, we describe the fifth documented case of xanthomatous meningioma and review its clinicopathological features. A 76-year-old Japanese male presented with dizziness. Magnetic resonance imaging demonstrated a well-circumscribed tumor in the left parasagittal to frontal region with attachment of the dura mater. Histopathological examination of the resected specimen revealed proliferation of polygonal to spindle cells with eosinophilic cytoplasm and bland round to oval nuclei. Whorl formation and psammomas were scattered, and mitotic figures were rarely seen. A peculiar finding was the presence of extensive xanthomatous change continuing to the above-mentioned typical meningothelial meningioma. These tumor cells had clear vacuolated cytoplasm and bland round to oval nuclei. Immunohistochemically, xanthomatous cells were positive for epithelial membrane antigen. Accordingly, an ultimate diagnosis of xanthomatous meningioma was made. Our clinicopathological analysis revealed that xanthomatous meningioma affects children to young persons or the elderly, and four of five cases were located in the supratentorial region. Although the detailed mechanism underlying the xanthomatous change has not been clarified, this change is thought to result from a metabolic abnormality of the neoplastic meningothelial cells. Further, xanthomatous change has also been reported in atypical and anaplastic meningiomas. Therefore, it is important to recognize that xanthomatous change can occur in meningiomas, and to avoid misidentifying these cells as macrophages.  相似文献   
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Follicular mucinosis is recognized as one of the histopathological reaction patterns characterized by the accumulation of mucin within follicular epithelium. It is induced by various causes including inflammatory diseases, and more than half of the cases are associated with malignant lymphoma, mainly mycosis fungoides. Herein, we describe the third documented case of adult T-cell leukemia/lymphoma (ATLL) accompanying follicular mucinosis. A 72-year-old Japanese male presented with persistent erythema in his arm and neck. Laboratory tests demonstrated positivity for human T-cell leukemia virus (HTLV)-1 antibodies. Histopathological study of the biopsy specimen from the neck revealed superficial perivascular, nodular, and intrafollicular lymphocytic infiltrations. These lymphocytes were small- to medium-sized and had convoluted nuclei. Mucoid material deposition was observed within the hair follicles, and it was digested by hyaluronidase. Immunohistochemically, these lymphocytes were positive for CD3, CD4, CD25, and Foxp3. Accordingly, an ultimate diagnosis of ATLL accompanying follicular mucinosis was made. The skin is the most common extralymphatic site of involvement of ATLL. The present case clearly demonstrated that albeit extremely rare, ATLL can cause follicular mucinosis. Therefore, ATLL should be included in the differential diagnostic consideration of follicular mucinosis.  相似文献   
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Contiguous ABCD1 DXS1357E deletion syndrome (CADDS) is a contiguous deletion syndrome involving the ABCD1 and DXS1357E/BAP31 genes on Xq28. Although ABCD1 is responsible for X‐linked adrenoleukodystrophy (X‐ALD), its phenotype differs from that of CADDS, which manifests with many features of Zellweger syndrome (ZS), including severe growth and developmental retardation, liver dysfunction, cholestasis and early infantile death. We report here the fourth case of CADDS, in which a boy had dysmorphic features, including a flat orbital edge, hypoplastic nose, micrognathia, inguinal hernia, micropenis, cryptorchidism and club feet, all of which are shared by ZS. The patient achieved no developmental milestones and died of pneumonia at 8 months. Biochemical studies demonstrated abnormal metabolism of very long chain fatty acids, which was higher than that seen in X‐ALD. Immunocytochemistry and Western blot showed the absence of ALD protein (ALDP) despite the presence of other peroxisomal proteins. Pathological studies disclosed a small brain with hypomyelination and secondary hypoxic‐ischemic changes. Neuronal heterotopia in the white matter and leptomeningeal glioneuronal heterotopia indicated a neuronal migration disorder. The liver showed fibrosis and cholestasis. The thymus and adrenal glands were hypoplastic. Array comparative genomic hybridization (CGH) analysis suggested that the deletion was a genomic rearrangement in the 90‐kb span starting in DXS1357E/BACP31 exon 4 and included ABCD1, PLXNB3, SRPK3, IDH3G and SSR4, ending in PDZD4 exon 8. Thus, the absence of ALDP, when combined with defects in the B‐cell antigen receptor associated protein 31 (BAP31) and other factors, severely affects VLCFA metabolism on peroxisomal functions and produces ZS‐like pathology.  相似文献   
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