Prognostic Factors Independently Associated with Improved Progression-Free Survival after Surgical Resection in Patients with Spinal Cord Astrocytomas: an Institutional Case Series.

BACKGROUND:Spinal astrocytomas are rare tumors in which the extent of resection and adjuvant therapy remain controversial. A number of new molecular markers are used, but their utility in spinal cord tumors remains unclear.OBJECTIVE:To determine prognostic indicators of progression-free survival (PFS) in patients with spinal astrocytomas.METHODS:A retrospective chart review identified all patients managed at a single institution for spinal cord astrocytomas between 1999 and 2019. Data collected included baseline demographics, presenting signs and symptoms, tumor size, operative outcomes, and adjuvant treatment. Pathological data including histopathological grade, proliferative index, and molecular profile were collected. Duration of follow-up, presence of tumor progression, and status at last follow-up were documented. Univariate and multivariate analyses were performed to determine predictors of PFS.RESULTS:Seventy-five patients were included in our study with an average age of 42 ± 17 yr. The thoracic spine was the most commonly involved spinal segment (50 patients), and most patients had grade I or grade II tumors (50 patients). On univariate analysis, gross total resection (GTR), lower tumor grade, and low Ki-67 index were associated with lower tumor progression (P-values .01, .04, and .00013, respectively). On multivariate Cox regression analysis, GTR, adjuvant chemotherapy and radiation, and low Ki-67 index were independent predictors of PFS (P-values .009, .011, and .031, respectively).CONCLUSION:In spinal astrocytomas, GTR, adjuvant therapy, and low Ki-67 are independently associated with improved PFS. These data may help guide management of these tumors and provide important prognosticating information.