Prognostic significance of contrast-enhancing anaplastic astrocytomas in adults

Abstract

Patients harboring anaplastic astrocytomas (AAs) typically have a poor prognosis, with median survival times of approximately 3 years following resection. However, a significant variability in individual outcomes remains, with some patients surviving for a few months and others for several years. The ability to predict patient outcomes based on preoperative variables would help prognosticate survival and may also guide treatment strategies. The prognostic implications of a preoperative contrast-enhancing AA remain poorly understood. The medical records of all patients who underwent a craniotomy for a hemispheric AA from 1996 to 2006 at a single institution were retrospectively reviewed. Multivariate proportional hazards regression analysis was used to identify independent associations with recurrence and survival. The Kaplan-Meier method and log-rank analysis were used to plot and compare outcomes for patients with and without preoperative contrast enhancement. One hundred sixty-five patients were available for analysis. The AAs were contrast enhancing in 102 patients (62%), and nonenhancing in 63 patients (38%). There were no significant differences in clinical and treatment-related variables between patients with and without contrast enhancement. After multivariate analysis, contrast enhancement was independently associated with decreased survival (p = 0.02) and increased recurrence (p = 0.04). The 5-year overall survival rates for patients with contrast-enhancing versus nonenhancing tumors were 31 and 38.5%, respectively. The 3-year rates of progression-free survival for patients with contrast-enhancing versus nonenhancing tumors were 32 and 56%, respectively. Interestingly, heterogeneously enhancing tumors appear to result in poorer outcomes as compared with other types of enhancement (such as ring enhancing, nodular, and others). Among patients with contrast-enhancing AAs, gross-total resection significantly delayed recurrence (p = 0.05) but did not significantly prolong survival (p = 0.52). This study may provide insights into risk-stratifying patients with AAs, and most specifically those with AAs that enhance with contrast administration.