Abstract
Malignant spinal cord astrocytomas are uncommon neoplasms that typically manifest with the acute onset of symptoms such as pain accompanied by motor and/or sensory disturbances. Most intramedullary spinal cord astrocytomas are low-grade, either diffuse WHO (World Health Organization) grade II, or less commonly, pilocytic astrocytomas (PA, grade I). Only 7.5% are diagnosed as high-grade astrocytomas, either anaplastic (AA, grade III) or glioblastoma (GBM, grade IV). Given the limited number of cases and often extremely small biopsies, there is no consensus regarding the prognostic significance of AA compared to GBM. In the largest retrospective study that stratified these two histopathologic grades, Santi et al. (Cancer 98:554–561, 2003) were unable to detect a difference in outcome. The authors acknowledge, however, that inadequate sampling may have biased the interpretation of the often tiny specimens. Only age appeared to correlate with prognosis, with shorter survival reported in patients older than 40 years at the onset of disease. More recently, McGirt et al. (Neurosurgery 63:55–66, 2008) found that patients with nondisseminated AA treated with radical resection showed a trend towards increased survival. With respect to patients with GBM who underwent radical resection, the overall survival was only 9 months. Despite largely anecdotal indications that local control may be beneficial, controversy persists regarding the prognostic value of the extent of resection. Similar concerns have been voiced regarding the benefits of adjuvant radiation or chemotherapy. The overall experience with high-grade spinal cord astrocytomas is that of relentless, aggressive growth with minimal chance of long term or recurrence-free survival.
Santi, Mariarita