Spinal Cord Astrocytomas: Treatment Considerations

Abstract

Purpose/Objective(s)To identify prognostic factors and to determine the impact of surgery and radiotherapy upon outcome of spinal cord astrocytomas.Patients/MethodsThe study consists of 136 consecutively operated patients with spinal cord astrocytoma treated at Mayo Clinic between 1962 and 2005. Extent of surgery included incisional biopsy (59%), subtotal resection (25%), and gross total resection (16%). Postoperative radiotherapy was delivered in 75% of cases.ResultsThe 136 cases included 69 pilocytic and 67 infiltrative astrocytomas with a median follow-up of 8.2 years (range 37.6–0.08 years). Patients with pilocytic tumors had a significantly better median overall survival as compared to those infiltrative astrocytomas (39.9 vs 1.85 years; p = <0.0001). For both pilocytic and infiltrative astrocytomas, patients who underwent more extensive resections had a worse outcome (pilocytic 39.7 vs 18.1 years, p = .066; infiltrative 42 vs 25 months, p = 0.137). Postoperative radiotherapy did not result in a significant survival benefit for pilocytic tumors but did for the infiltrative astrocytomas (pilocytic 39.8 vs 18.1 years; p = 0.329; infiltrative 24 vs 3 months; p = .006). Multivariate analyses found pilocytic histology, diagnosis in the MRI era, longer symptom duration, younger age, minimal extent of surgery, post-operative radiotherapy to be predictive of a better outcome.ConclusionsHistology is the most important prognostic variable affecting spinal cord astrocytomas. Surgical resection exceeding biopsy results in less favorable survival and thus remains an unproven treatment. Postoperative radiation therapy significantly improves survival of patients with infiltrative fibrillary astrocytomas but not for those with pilocytic tumors. Purpose/Objective(s)To identify prognostic factors and to determine the impact of surgery and radiotherapy upon outcome of spinal cord astrocytomas. To identify prognostic factors and to determine the impact of surgery and radiotherapy upon outcome of spinal cord astrocytomas. Patients/MethodsThe study consists of 136 consecutively operated patients with spinal cord astrocytoma treated at Mayo Clinic between 1962 and 2005. Extent of surgery included incisional biopsy (59%), subtotal resection (25%), and gross total resection (16%). Postoperative radiotherapy was delivered in 75% of cases. The study consists of 136 consecutively operated patients with spinal cord astrocytoma treated at Mayo Clinic between 1962 and 2005. Extent of surgery included incisional biopsy (59%), subtotal resection (25%), and gross total resection (16%). Postoperative radiotherapy was delivered in 75% of cases. ResultsThe 136 cases included 69 pilocytic and 67 infiltrative astrocytomas with a median follow-up of 8.2 years (range 37.6–0.08 years). Patients with pilocytic tumors had a significantly better median overall survival as compared to those infiltrative astrocytomas (39.9 vs 1.85 years; p = <0.0001). For both pilocytic and infiltrative astrocytomas, patients who underwent more extensive resections had a worse outcome (pilocytic 39.7 vs 18.1 years, p = .066; infiltrative 42 vs 25 months, p = 0.137). Postoperative radiotherapy did not result in a significant survival benefit for pilocytic tumors but did for the infiltrative astrocytomas (pilocytic 39.8 vs 18.1 years; p = 0.329; infiltrative 24 vs 3 months; p = .006). Multivariate analyses found pilocytic histology, diagnosis in the MRI era, longer symptom duration, younger age, minimal extent of surgery, post-operative radiotherapy to be predictive of a better outcome. The 136 cases included 69 pilocytic and 67 infiltrative astrocytomas with a median follow-up of 8.2 years (range 37.6–0.08 years). Patients with pilocytic tumors had a significantly better median overall survival as compared to those infiltrative astrocytomas (39.9 vs 1.85 years; p = <0.0001). For both pilocytic and infiltrative astrocytomas, patients who underwent more extensive resections had a worse outcome (pilocytic 39.7 vs 18.1 years, p = .066; infiltrative 42 vs 25 months, p = 0.137). Postoperative radiotherapy did not result in a significant survival benefit for pilocytic tumors but did for the infiltrative astrocytomas (pilocytic 39.8 vs 18.1 years; p = 0.329; infiltrative 24 vs 3 months; p = .006). Multivariate analyses found pilocytic histology, diagnosis in the MRI era, longer symptom duration, younger age, minimal extent of surgery, post-operative radiotherapy to be predictive of a better outcome. ConclusionsHistology is the most important prognostic variable affecting spinal cord astrocytomas. Surgical resection exceeding biopsy results in less favorable survival and thus remains an unproven treatment. Postoperative radiation therapy significantly improves survival of patients with infiltrative fibrillary astrocytomas but not for those with pilocytic tumors. Histology is the most important prognostic variable affecting spinal cord astrocytomas. Surgical resection exceeding biopsy results in less favorable survival and thus remains an unproven treatment. Postoperative radiation therapy significantly improves survival of patients with infiltrative fibrillary astrocytomas but not for those with pilocytic tumors.