Primitive Neroectodermal Tumor in the Cauda Equina Region

ABSTRACT

We report a malignant peripheral primitive neuroectodermal tumor (PNET) that originated in the cauda equina in a young adult, After gross total excision of the tumor, radiotheraphy was followed. The tumor had the typical appearance of a PNET with small, round cell. It stained positively for the neuron-specific enolase(NSE) conforming its neural origin and negatively for cytokeratin, glial fibrillary acidic protein(GFAP ) and S-100 protein. Three months later, MRI showed almost total obstruction at the level o f the L/L interspace caused by a mass occupying the spinal canal and extending into the L/S foramen on the right. Sixteen months after commencement of radiotherapy, severe left sciatica developed and MRI showed involvement of the both ilii and right femur with a large soft tissue mass extending into the pelvis. Palliative radiotherapy was administered but the patient died four months later.