title: Spinal hamartomas: a distinct clinical entity.
abstract: OBJECTIVE
  Congenital spinal hamartomas are defined as tumors of well-differentiated mature elements situated in an abnormal location. In this report, the authors document the clinical and pathological features of spinal hamartomas in 10 patients.
  
  
  METHODS
  Ten patients presented with midline dorsal malformations at birth, initially diagnosed as teratomas or myelomeningoceles. The locations of the masses were variable: two were located in the thoracic region, four at the thoracolumbar junction, two in the lumbar region, one at the lumbosacral junction, and one in the sacral region. The results of the neurological examination were normal in nine patients. All but one mass had intact skin and seven had palpable bone components. Neuroimaging studies revealed widening of the spinal canal, heterotopic bone located dorsally in some patients, and varying degrees of involvement of the intraspinal contents. During surgery, six patients were found to have involvement of the spinal cord or cauda equina. The pathological characteristics of the masses included three or more of the following: bone, cartilage, synovial membrane, urinary tract tissue, cyst wall, yellow or brown fat, and nerves. The well-differentiated cellular elements, which formed mature structures, along with the absence of primitive cellular components and neoplastic characteristics are more consistent with a diagnosis of hamartoma than teratoma.
  
  
  CONCLUSIONS
  In this series, the authors describe a lesion that is overt on physical examination, yet can have occult spinal canal involvement. Complete neurosurgical evaluation is essential to provide appropriate treatment and prognosis.
authors.affiliation: Division of Neurosurgery, School of Medicine, University of California at San Diego, USA.
authors.forename: G F
authors.initials: GF
authors.lastname: Morris
authors.forename: K
authors.initials: K
authors.lastname: Murphy
authors.forename: L B
authors.initials: LB
authors.lastname: Rorke
authors.forename: H E
authors.initials: HE
authors.lastname: James
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D002001:Adipose Tissue, Brown / Q000473:pathology; D001842:Bone and Bones / Q000473:pathology; D002356:Cartilage / Q000473:pathology; D002420:Cauda Equina / Q000473:pathology; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006222:Hamartoma / Q000151:congenital* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007231:Infant, Newborn; D008159:Lumbar Vertebrae / Q000473:pathology; D008591:Meningomyelocele / Q000175:diagnosis; D009460:Neurologic Examination; D009474:Neurons / Q000473:pathology; D009999:Ossification, Heterotopic / Q000473:pathology; D011379:Prognosis; D012447:Sacrum / Q000473:pathology; D012867:Skin / Q000473:pathology; D013115:Spinal Canal / Q000473:pathology; D013116:Spinal Cord / Q000473:pathology; D013122:Spinal Diseases / Q000151:congenital* / Q000473:pathology / Q000601:surgery; D013125:Spinal Neoplasms / Q000175:diagnosis; D013583:Synovial Membrane / Q000473:pathology; D013724:Teratoma / Q000175:diagnosis; D013904:Thoracic Vertebrae / Q000473:pathology; D014551:Urinary Tract / Q000473:pathology