title: Pigmented paraganglioma of the kidney: a case report.
abstract: Paragangliomas are rare neoplasms arising from undifferentiated cells of the primitive neural crest. We report a case of a 57-year-old patient with renal pigmented paraganglioma that was an incidental finding. Histopathological examination showed typical morphology of paraganglioma, as well as the unusual feature of large amounts of pigment in the cytoplasm of the tumor cells which was confirmed by bleached Fontana-Masson. Electron microscopy showed abundant, pleomorphic electron-dense granules consistent with neuromelanin. The tumor cells were positive for CD56 and chromogranin A, negative for HMB-45. The unique morphologic appearance represents divergent differentiation from neural crest. To our knowledge, the present case represents the first example of pigmented paraganglioma of the kidney.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2017147293711495.
authors: Department of Pathology, China-Japan Friendship Hospital, Beijing, 100029, China.
authors: Ling
authors: L
authors: Zhao
authors: Jie
authors: J
authors: Luo
authors: Honglei
authors: H
authors: Zhang
authors: Jiping
authors: J
authors: Da
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D019002:CD56 Antigen / Q000032:analysis; D053379:Chromogranin A / Q000032:analysis; D003594:Cytoplasmic Granules / Q000737:chemistry* / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000737:chemistry* / Q000000981:diagnostic imaging / Q000648:ultrastructure; D008297:Male; D008543:Melanins / Q000032:analysis*; D058950:Melanoma-Specific Antigens / Q000032:analysis; D008854:Microscopy, Electron; D008875:Middle Aged; D010236:Paraganglioma, Extra-Adrenal / Q000737:chemistry* / Q000000981:diagnostic imaging / Q000648:ultrastructure; D014057:Tomography, X-Ray Computed; D058951:gp100 Melanoma Antigen
chemical_list: D014408:Biomarkers, Tumor; D019002:CD56 Antigen; C506150:CHGA protein, human; D053379:Chromogranin A; D008543:Melanins; D058950:Melanoma-Specific Antigens; C522918:NCAM1 protein, human; C548637:PMEL protein, human; D058951:gp100 Melanoma Antigen; C014121:neuromelanin