title: Intradural cauda equina metastasis of renal cell carcinoma: a case report with literature review of 10 cases.
abstract: METHODS
  Case report with literature review.
  
  
  OBJECTIVE
  To describe a rare case of intradural spinal metastasis from renal cell carcinoma (RCC) spread to the cauda equina, and to discuss the clinical features of metastatic RCC in the cauda equina from the data available in the literature.
  
  
  BACKGROUND
  Intradural spinal metastasis is rare, representing 6% of all spinal metastasis. Indeed, intradural metastasis from a RCC to the cauda equina is extremely rare with previously only 9 case reports.
  
  
  METHODS
  A 68-year-old male presented with a 2-month history of worsening lower back pain radiating to both legs. The patient had undergone nephrectomy for the treatment of the clear cell RCC 16 years before admission. Magnetic resonance imaging showed a well-defined intradural extramedullary mass in the cauda equina at T12 to L1.
  
  
  RESULTS
  The pathological examination displayed metastatic clear cell RCC. Additional imaging studies showed no metastatic in other locations. The patient was discharged without neurological deficit and pain after the operation, and maintained an optimal condition for 2 years.
  
  
  CONCLUSIONS
  When a lesion of the cauda equina presents, intradural metastasis should be in the differential diagnosis in patients who had been previously treated for RCC although any other metastatic lesion was not observed.
  
  
  METHODS
  N/A.
authors.affiliation: Department of Neurosurgery, Guro Teun Teun Hospital, Seoul, Korea.
authors.forename: Gyu Yeul
authors.initials: GY
authors.lastname: Ji
authors.forename: Chang Hyun
authors.initials: CH
authors.lastname: Oh
authors.forename: Se-Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Dong Ah
authors.initials: DA
authors.lastname: Shin
authors.forename: Keung Nyun
authors.initials: KN
authors.lastname: Kim
mesh_terms: D000368:Aged; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000601:surgery; D002420:Cauda Equina / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000601:surgery; D008297:Male; D010524:Peripheral Nervous System Neoplasms / Q000175:diagnosis* / Q000556:secondary / Q000601:surgery; D013120:Spinal Cord Neoplasms / Q000175:diagnosis* / Q000556:secondary / Q000601:surgery