title: Malignant perivascular epithelioid cell tumor of the kidney with rare pulmonary and ileum metastases.
abstract: OBJECTIVE
  To report one case of malignant perivascular epithelioid cell tumor (PEComa) of the kidney with rare pulmonary and ileum metastases and analyze its clinicopathological features.
  
  
  METHODS
  We analyzed the clinicopathological features of one case of malignant PEComa of the kidney with pulmonary and ileum metastases. Immunohistochemistry staining was performed.
  
  
  RESULTS
  The patient was a 48-year-old man with a renal mass approximately 14 cm × 11 cm × 8 cm in size. Microscopically, the tumor was mainly composed of polygonal epithelioid cells with dense eosinophilic cytoplasm and round nuclei with small nucleoli. Focal tumor cells showed pleomorphism with multinucleated giant cells and prominent nucleoli. The tumor cells nests were surrounded by thick-walled irregular blood vessels. Focal fat cells were found within the tumor. Hemorrhage and coagulative necrosis were also present. The tumor cells were positive for vimentin, HMB45, and Melan-A, and focally positive for SMA and S-100 protein. After 5 years and 5.6 years of nephrectomy, the tumor metastasized to the right lung and ileum, respectively.
  
  
  CONCLUSIONS
  We first reported one case of malignant PEComa of the kidney with pulmonary and ileum metastases. Metastatic PEComa of the lung and ileum should differentiate from primary carcinoma, metastatic carcinoma, malignant melanoma, and gastrointestinal stromal tumor.
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Cao
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Tiantian
authors.initials: T
authors.lastname: Zhen
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Yingrong
authors.initials: Y
authors.lastname: Lai
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-Sen University Guangzhou, China.
authors.forename: Anjia
authors.initials: A
authors.lastname: Han
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D003937:Diagnosis, Differential; D006801:Humans; D007078:Ileal Neoplasms / Q000737:chemistry / Q000556:secondary* / Q000601:surgery; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D008175:Lung Neoplasms / Q000737:chemistry / Q000556:secondary* / Q000601:surgery; D008297:Male; D059146:Metastasectomy; D008875:Middle Aged; D009392:Nephrectomy; D054973:Perivascular Epithelioid Cell Neoplasms / Q000737:chemistry / Q000556:secondary* / Q000601:surgery; D011013:Pneumonectomy; D011237:Predictive Value of Tests; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor
keywords: Perivascular epithelioid cell tumor; ileum; kidney; lung; metastasis