Spinal cord astrocytomas: presentation, management and outcome

Intramedullary spinal cord astrocytomas are uncommon tumors. They are the m ost common spinal cord tumor in children and in adults are second only to e pendymomas in frequency of occurrence. Low-grade histology predominates wit h high-grade lesions comprising only ten to fifteen percent of pediatric tu mors and a slightly higher proportion in adults. Presenting symptoms typica lly evolve over months to years with regional back pain the most commonly r eported initial complaint. Malignant tumors produce rapid neurological dete rioration. MRI is the diagnostic modality of choice: spinal cord astrocytom as are iso- to slightly hypointense on T1, hyperintense on T2 and commonly have associated cysts. They enhance less intensely and are more eccentric t han ependymomas. The goals of surgical intervention are to obtain a tissue diagnosis and resect as much tumor as possible without adversely affecting neurological function. Astrocytomas are infiltrating neoplasms and total re section is not generally possible. Somatosensory and motor evoked potential monitoring are routinely used but it is unclear if they improve outcomes. The operating microscope and bipolar cautery are essential surgical tools; the ultrasound and ultrasonic surgical aspirator are useful surgical adjunc ts. Laminectomy is performed on adults while laminoplasty is favored for pe diatric patients. Outcome for low-grade astrocytomas is less favorable than that of ependymomas with regard to both recurrence and function though man y have prolonged survival. There is no correlation of extent of resection a nd recurrence. Outcome for high-grade tumors is extremely poor; tumor progr ession is relentless; median survival is thirteen months in children and si x months in adults.