title: Malignant mesothelioma of the tunica vaginalis.
abstract: BACKGROUND
  Malignant mesothelioma involving the tunica vaginalis is an extremely rare tumor.
  
  
  METHODS
  We describe a case of a 39-year-old man who initially presented with discomfort in the left testis and underwent resection of a hydrocele in the left testis. A pathology examination of a frozen section of a lesion on the tunica identified the lesion as mesothelioma, which was confirmed by a second pathology examination. No metastatic disease was found. The patient subsequently underwent a left radical orchiectomy and a partial scrotectomy, and has been disease free for 7 years.
  
  
  CONCLUSIONS
  The first case of malignant mesothelioma involving the tunica vaginalis, a structure embryologically derived from a layer of reflected peritoneum known as the "processus vaginalis," was reported in 1957. Only 73 cases were reported in the literature between 1966 and 1997. In up to 41% of cases, there is a positive history of asbestos exposure. Young age and localized disease are associated with a better prognosis. Radical orchiectomy limits recurrence, which usually occurs within 2 years, but may occur up to 15 years after surgery.
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Al-Qahtani
authors.forename: Brian
authors.initials: B
authors.lastname: Morris
authors.forename: Shaheenah
authors.initials: S
authors.lastname: Dawood
authors.forename: Ronald
authors.initials: R
authors.lastname: Onerheim
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis* / Q000473:pathology; D013736:Testicular Neoplasms / Q000175:diagnosis* / Q000473:pathology