title: Leiomyoma of the renal capsule: case report and literature review.
abstract: BACKGROUND
  Mesenchymal tumors are an exceptional finding in the urinary tract and renal leiomyoma is even more rare. They are usually discovered incidentally during ultrasonography examinations or autopsy. Sometimes they are clinically symptomatic with hematuria, flank pain, or palpable mass. Till today, it is still difficult to make a diagnosis of leiomyoma using the radiological examinations. Although conventional imaging has a high sensitivity and specificity in the detection of both retroperitoneal and renal masses, the diagnosis is based on histological examination, due to the poor discrimination accuracy between different retroperitoneal tumors.
  
  
  METHODS
  We report a case of renal leiomyoma in a 47-year-old woman, who incidentally discovered a retroperitoneal mass with an abdominal ultrasound scheduled for a conventional follow-up schedule of a mammary neoplasm. Partial nephrectomy was carried out with an open flank surgical approach and the diagnosis was "leiomyoma of the renal capsule". Four years after surgery, the patient is disease-free.
  
  
  CONCLUSIONS
  Renal leiomyomas are rare, benign, nonmetastasizing tumors with a good prognosis after surgical treatment. At present, the differential diagnosis is still possible by histopathological examination.
authors.affiliation: 1 Clinic of Urology, Catholic University of Sacred Heart, Rome - Italy.|2 Department of Urology, ASST Bergamo Est, Bergamo - Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Filianoti
authors.affiliation: 2 Department of Urology, ASST Bergamo Est, Bergamo - Italy.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Paganelli
authors.affiliation: 1 Clinic of Urology, Catholic University of Sacred Heart, Rome - Italy.
authors.forename: PierFrancesco
authors.initials: P
authors.lastname: Bassi
authors.affiliation: 3 Department of Urology, Regina Elena Hospital, Rome - Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Simone
authors.affiliation: 2 Department of Urology, ASST Bergamo Est, Bergamo - Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ranieri
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D033162:Incidental Findings; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D007889:Leiomyoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D008875:Middle Aged; D009392:Nephrectomy; D012307:Risk Factors; D016896:Treatment Outcome; D014463:Ultrasonography / Q000379:methods
keywords: Benign tumor; Leiomyoma; Renal capsule; Renal tumor