title: Iatrogenic intraspinal epidermoid tumor: two cases and a review of the literature.
abstract: METHODS
  Two cases of patients whom intraspinal epidermoid tumors presented and were successfully removed 6 years after neonatal lumbar puncture are reported.
  
  
  OBJECTIVE
  To describe the presentation of this type of spinal tumor and strategies for diagnosis and treatment.
  
  
  BACKGROUND
  Cells iatrogenically implanted into the spinal canal during lumbar puncture can slowly grow until symptomatic. Diagnosis can be difficult and is often delayed. MRI appears to offer some advantages in diagnosis provided that gadolinium is used. Treatment is by surgical excision.
  
  
  METHODS
  The first patient, a 6-year-old boy, presented with severe episodic hip pain of unknown etiology. MRI of the lumbar spine revealed a 1-cm epidermoid at L1-L2. The second child, a 6-year-old girl, presented with low back pain and dragging of the feet. MRI revealed a mass at L3.
  
  
  RESULTS
  In both cases, complete excision via lumbar laminectomy was performed. Both patients were asymptomatic at the 1-year follow-up with resolution of preoperative weakness.
  
  
  CONCLUSIONS
  This study highlights an uncommon but not rare tumor that may present to the spine specialist in a variety of ways. The diagnosis is often delayed. The advent of MRI has improved the ease and accuracy of diagnosis. Complete excision is usually possible and is curative.
authors.affiliation: Department of Orthopaedic Surgery, Children's Hospital Los Angeles, University of Southern California School of Medicine, Los Angeles, CA 90027, USA.
authors.forename: Eli T
authors.initials: ET
authors.lastname: Ziv
authors.forename: J
authors.initials: J
authors.lastname: Gordon McComb
authors.forename: Mark D
authors.initials: MD
authors.lastname: Krieger
authors.forename: David L
authors.initials: DL
authors.lastname: Skaggs
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000209:etiology* / Q000601:surgery; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007049:Iatrogenic Disease; D007796:Laminectomy / Q000379:methods; D017116:Low Back Pain / Q000209:etiology; D008159:Lumbar Vertebrae / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D013125:Spinal Neoplasms / Q000209:etiology* / Q000601:surgery; D013129:Spinal Puncture / Q000009:adverse effects*; D016896:Treatment Outcome