Introduction: There are currently no clear treatment guidelines for the management of spinal cord astrocytomas. Additionally there is no conclusive evidence for the surgical resection of these tumors, with some studies even demonstrating worse survival with surgery. However, most studies have examined patients treated prior to the routine use of magnetic resonance imaging and advanced microsurgical techniques. In this study, the authors have examined the effect of resection on survival and neurological outcome in a modern cohort of patients with spinal cord astrocytomas.
Methods: A retrospective review was performed of patients with spinal cord astrocytomas treated at the Duke University Medical Center from 1992 to 2012. Univariate and multivariate analyses were utilized to identify variables associated with survival.
Results: A total of 46 consecutive patients were identified and included in the analysis, most of whom had low grade tumors (63.0%). The majority of patients (67.4%) underwent surgical resection, with the remaining only receiving biopsy. Of those who underwent resection, only 12.5% of patients underwent gross total resection, all of whom had low grade astrocytomas. Of all patients, 30.7% worsened compared to their preoperative baseline. The occurrence of worsening increased with high tumor grade (52.9% vs. 27.6%, p=0.086) and an increased extent of resection (66.7% vs. 18.8%, p=0.0069). Resection did not provide a survival benefit compared to biopsy alone (p=0.53). Multivariate analysis revealed high grade histology (HR:11.3;95%CI:2.41-53.2;p=0.0021), tumor dissemination (HR:4.24;95%CI:1.22-14.8;p=0.023), and an increasing number of tumor involved levels (HR:1.31;95%CI:0.99-1.74;p=0.058) to be associated with worse survival.
Conclusions: As surgical intervention is associated with a higher rate of neurological complications and lacks a clear benefit, the resection of spinal cord astrocytomas should be reserved for select cases and should be utilized sparingly.
Patient Care: Currently, while surgical resection and the extent of resection have been shown to improve the outcomes of patients with supratentorial astrocytomas, there is no such conclusive evidence for spinal cord
astrocytomas. Additionally, the vast majority of spinal cord astrocytoma studies have included patients diagnosed and treated prior to the routine use of magnetic resonance imaging and advanced microsurgical techniques, potentially confounding the effect of resection due to poorer resection quality and worse postoperative neurological outcomes. In this study, we have performed an in-depth analysis of a modern cohort of patients with intramedullary spinal cord astrocytomas. We have shown an increased extent of resection to increase the risk of postoperative neurological worsening, especially for those with high grade astrocytomas. However, resection was not seen to provide a survival benefit. Multivariate analysis revealed high grade histology and tumor dissemination to be significant predictors of poor survival, with the number of tumor involved levels approaching significance. We conclude that as surgical intervention is associated with a higher rate of neurological complications and lacks a clear benefit, the resection of spinal cord astrocytomas should be reserved for select cases and should be utilized sparingly. We hope that this study increases awareness of the limitations of surgical resection for the treatment of spinal cord astrocytomas and stimulates further study.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of astrocytoma grade on the development of postoperative complications following resection, 2) Discuss, in small groups, the pros and cons of surgical resection for the treatment of spinal cord astrocytomas, 3) Identify an effective treatment strategy for spinal cord astrocytomas.