title: Intradural metastasis to the cauda equina from carcinoma of the anus.
abstract: METHODS
  This is a report of a man with carcinoma of the anus and intradural metastasis to the cauda equina.
  
  
  OBJECTIVE
  To perform a laminectomy with tumor removal for relief of pain.
  
  
  BACKGROUND
  Only 25 cases of intradural spinal metastasis have been reported in the English literature. This is the first report of a metastatic case, moving from the carcinoma of the anus to the cauda equina.
  
  
  METHODS
  Magnetic resonance imaging showed an ill-defined mass, with central necrosis, to the cauda equina. The possibility of intradural metastasis to the cauda equina was indicated by unique pain symptoms.
  
  
  RESULTS
  The patient's back pain subsided after total laminectomy of L3-L5 with subtotal removal of the tumor. The residual tumor became smaller with postoperative radiation.
  
  
  CONCLUSIONS
  Magnetic resonance imaging is a good diagnostic choice in this situation. The cause of the metastasis was unclear, but it was presumed to have occurred through the perineural lymphatic ducts. Laminectomy with tumor removal is feasible for relieving pain and demonstrating pathology.
authors.affiliation: Department of Surgery, Taichung Veterans General Hospital, Taiwan, Republic of China.
authors.forename: D Y
authors.initials: DY
authors.lastname: Cho
authors.forename: Y C
authors.initials: YC
authors.lastname: Wang
authors.forename: J T
authors.initials: JT
authors.lastname: Chen
mesh_terms: D001003:Anal Canal / Q000473:pathology; D001005:Anus Neoplasms / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000150:complications / Q000175:diagnosis / Q000556:secondary* / Q000601:surgery; D002420:Cauda Equina / Q000473:pathology; D003131:Combined Modality Therapy; D006801:Humans; D007796:Laminectomy; D017116:Low Back Pain / Q000209:etiology; D008159:Lumbar Vertebrae / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010524:Peripheral Nervous System Neoplasms / Q000150:complications / Q000175:diagnosis / Q000556:secondary* / Q000601:surgery