title: [Melanotic epithelioid clear cell tumor of kidney: report of three cases].
abstract: OBJECTIVE
  To study the pathologic features and immunophenotype of 3 cases of melanotic epithelioid clear cell tumor of kidney.
  
  
  METHODS
  More than 2000 cases of renal tumors were retrospectively reviewed. Three cases of melanotic epithelioid clear cell tumor were identified. Immunohistochemical study was carried out using the paraffin-embedded tissue samples. Electron microscopy was also performed in 1 case.
  
  
  RESULTS
  Amongst the 3 cases studied, the male-to-female ratio is 1:2. Histologically, 2 cases showed a clear cell carcinoma-like pattern. Papillary structures covered by clear cells and eosinophilic cells were observed in 1 case. Immunohistochemical study showed that the tumor cells in all cases expressed HMB 45. Two of them were also positive for Melan A. The staining for epithelial markers and S-100 protein was negative. Melanosomes were not identified by ultrastructural examination.
  
  
  CONCLUSIONS
  Melanotic epithelioid clear cell tumor is a rarely seen neoplasm of kidney. There are some histologic overlaps with renal cell carcinoma, epithelioid angiomyolipoma and melanoma. Immunohistochemical study is useful in confirming the diagnosis. The tumor represents a morphologic variant of epithelioid angiomyolipoma.
authors.affiliation: Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai 200032, China. junhoudaily@yahoo.com.cn
authors.forename: Jun
authors.initials: J
authors.lastname: Hou
authors.forename: Jian-Fang
authors.initials: JF
authors.lastname: Xu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ji
authors.forename: Ying-Yong
authors.initials: YY
authors.lastname: Hou
authors.forename: Yun-Shan
authors.initials: YS
authors.lastname: Tan
authors.forename: Akesu
authors.initials: A
authors.lastname: Sujie
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.forename: Da-Ren
authors.initials: DR
authors.lastname: Shi
mesh_terms: D000293:Adolescent; D000328:Adult; D018207:Angiomyolipoma / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D002292:Carcinoma, Renal Cell / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D015622:Epithelioid Cells / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D058965:MART-1 Antigen / Q000378:metabolism; D008297:Male; D058950:Melanoma-Specific Antigens / Q000378:metabolism*; D012189:Retrospective Studies
chemical_list: D058965:MART-1 Antigen; D058950:Melanoma-Specific Antigens