SPINAL HAMARTOMAS - A DISTINCT CLINICAL ENTITY

Object. Congenital spinal hamartomas are defined as tumors of well-dif ferentiated 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 wit h midline dorsal malformations at birth, initially diagnosed as terato mas or myelomeningoceles. The locations of the masses were variable: t wo were located in the thoracic region, four at the thoracolumbar junc tion, two in the lumbar region, one at the lumbosacral junction, and o ne in the sacral region. The results of the neurological examination w ere normal in nine patients. All but one mass had intact skin and seve n had palpable bone components. Neuroimaging studies revealed widening of the spinal canal, heterotopic bone located dorsally in some patien ts, and varying degrees of involvement of the intraspinal contents. Du ring surgery, six patients were found to have involvement of the spina l cord or cauda equina. The pathological characteristics of the masses included three or more of the following: bone, cartilage, synovial me mbrane, urinary tract tissue, cyst wall, yellow or brown fat, and nerv es. The well-differentiated cellular elements, which formed mature str uctures, along with the absence of primitive cellular components and n eoplastic characteristics are more consistent with a diagnosis of hama rtoma than teratoma. Conclusions. In this series, the authors describe a lesion that is overt on physical examination, yet can have occult s pinal canal involvement. Complete neurosurgical evaluation is essentia l to provide appropriate treatment and prognosis.