title: Perivascular epithelioid cell neoplasm of the urinary bladder in an adolescent: a case report and review of the literature.
abstract: Perivascular epithelioid cell neoplasms (PEComas) of the urinary bladder are extremely rare and the published cases were comprised predominantly of middle-aged patients. Herein, the authors present the first urinary bladder PEComa occurring in an adolescent. This 16-year-old Chinese girl present with a 3-year history of abdominal discomfort and a solid mass was documented in the urinary bladder by ultrasonography. Two years later, at the age of 18, the patient underwent transurethral resection of the bladder tumor. Microscopically, the tumor was composed of spindled cells mixed with epithelioid cells. Immunohistochemically, the tumor were strongly positive for HMB45, smooth muscle actin, muscle-specific actin, and H-caldesmon. Fluorescence in situ hybridization analysis revealed no evidence of EWSR1 gene rearrangement. The patient had been in a good status without evidence of recurrence 13 months after surgery. Urinary bladder PEComa is an extremely rare neoplasm and seems occur predominantly in middle-aged patients. However, this peculiar lesion can develop in pediatric population and therefore it should be rigorously distinguished from their mimickers.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1870004378817301.
authors.affiliation: Department of Pathology, West China Hospital, Sichuan University, Guoxuexiang 37, 610041 Chengdu, Sichuan, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Yin
authors.forename: Hong
authors.initials: H
authors.lastname: Bu
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Jianqun
authors.initials: J
authors.lastname: Yu
authors.forename: Hua
authors.initials: H
authors.lastname: Zhuang
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D015653:Cystectomy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D054973:Perivascular Epithelioid Cell Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor