title: Mixed epithelial and stromal tumor of the kidney (MEST).
abstract: OBJECTIVE
  To report an unusual case of renal tumor and review the literature.
  
  
  METHODS
  We present a 20 years old female with a history of acute right pyelonephritis. The ultrasound study revealed a tumor-like image in the lower pole  of the right kidney . The CT-scan showed a mixed solid and cystic mass of 7 cm. in the lower pole of the right kidney.
  
  
  RESULTS
  A right laparoscopic partial nephrectomy was performed. The total operative time was 90 minutes, with 24 minutes of warm ischemia. The estimated blood  loss was 50 ml. and the length of stay (LOS) 36 hours. The pathology findings confirm a mixed epithelial and stromal tumor (MEST) of the kidney.
  
  
  CONCLUSIONS
  Mixed epithelial and stromal tumor (MEST) of the kidney is a benign and rare condition that doesn't show a clear difference with other renal tumors  in image studies. Nephron-sparing surgery with margin study is the standard treatment when is feasible.
authors.affiliation: Urology Department, Clínica Indisa, Faculty of Medicine, Andres Bello University, Santiago, Chile.
authors.forename: Gaston
authors.initials: G
authors.lastname: Lopez-Fontana
authors.forename: Ivan
authors.initials: I
authors.lastname: Gallegos
authors.forename: Francisco
authors.initials: F
authors.lastname: Sepúlveda
authors.forename: Jose Ignacio
authors.initials: JI
authors.lastname: Bonomo
authors.forename: Octavio A
authors.initials: OA
authors.lastname: Castillo
mesh_terms: D002277:Carcinoma / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D018193:Neoplasms, Complex and Mixed / Q000473:pathology* / Q000601:surgery; D009392:Nephrectomy; D011704:Pyelonephritis / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D017154:Stromal Cells / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D055815:Young Adult