Advantages of gross total resection in patients with astrocytoma: A population-based study

The present study aimed to investigate the association between surgical methods and survival outcomes in patients with astrocytoma. Patients diagnosed with astrocytoma between January 2004 and December 2015 were identified using the Surveillance, Epidemiology and End Results database. Kaplan-Meier curves and Cox regression were used to analyze the effects of surgical methods on overall survival (OS) and cancer-specific survival (CSS). Among 42,224 eligible patients with astrocytoma, 11,427 (27.1%) patients did not receive surgery, 7,661 (18.1%) received excisional biopsy (EB), 5,520 (13.1%) received a subtotal resection (STR), 6,037 (14.3%) received a gross resection (GR), 5,314 (12.6%) received a partial resection (PR) and 6,265 (14.8%) received a gross total resection (GTR). Patients who underwent GR had the longest survival time (17.00 months). However, over time, the proportion of patients who underwent STR or GR increased, whereas the proportion of patients who did not undergo surgery, PR or GTR decreased. Furthermore, surgical method was an independent prognostic factor for OS and CSS for the patients with astrocytoma. Multivariate Cox regression showed that GTR was associated with the more favorable OS [hazard ratio (HR), 0.80; 95% confidence interval (CI), 0.77-0.83; P<0.001] and CSS (HR, 0.80; 95% CI, 0.77-0.83; P<0.001) times compared with EB. Moreover, similar results were observed in subgroup analyses based on summary stage and grade. In the present study, it was demonstrated that GTR was one of the effective surgical methods for improved OS and CSS time in patients with astrocytoma. However, among the American astrocytoma population, the proportion of patients who underwent GTR decreased. It is necessary to further advocate for the efficacy of GTR.