Astrocytoma

Astrocytomas are uncommon entities in the spinal canal, comprising only 6-8% of all spinal cord tumors. They include pilocytic astrocytoma (WHO grade I), diffuse astrocytoma (WHO grade II), anaplastic astrocytoma (WHO grade III), and glioblastoma (WHO grade IV). Lower-grade (WHO grade I and II) lesions make up 75% of spinal cord astrocytomas. The authors concentrate on the diagnosis and treatment of these low-grade astrocytomas in adults. Patients may present with vague and progressive neurological complaints. Symptoms most commonly include pain and dysesthesias, motor weakness, sensory deficits, gait ataxia, and sphincter problems. MRI is the imaging modality of choice and usually reveals a hypointense T1-weighted and hyperintense T2-weighted lesion with heterogeneous contrast enhancement. On axial scans, astrocytomas are often eccentric, as they originate from the glial tissue, creating a localized expansion of the spinal cord. Prognostic factors for patients with spinal astrocytomas include age, histological diagnosis (morphology/WHO grade), and preoperative neurological function. The strongest predicting factor of functional outcome is the preoperative neurological condition, whereas age greater than 60 year old, pathologic grade, and failure to achieve a gross total resection are strong negative predictors. The extent of surgical resection shows a significant association with survival and reduction in the risk of disease progression. While often not attainable, the goal of treatment should be gross total resection of the tumor with the use of microsurgical technique aided by intraoperative neuromonitoring (SSEP/MEP) to preserve neurological function and avoid neurological deficit. Adjuvant radiation therapy has been shown to improve survival, while the use of chemotherapy is often reserved for those who fail conventional treatment with surgery and radiation. The 5-year overall survival rate for WHO grades I and II is 70-82% and mean survival of approximately 50 months. Due to the rarity and overall poor prognosis of spinal cord astrocytomas, further research is necessary to improve treatment and patient outcomes.