Prognostic factors among single primary gliosarcoma cases: A study using Surveillance, Epidemiology, and End Results data from 1973-2013

Background Prognostic factors for single primary gliosarcoma (PGS) remain unknown. Objective The purpose of our study was to examine patient, tumor, and treatment characteristics as potential predictors of survival using Surveillance, Epidemiology, and End Results (SEER) program data (1973-2013). Methods The patients of single PGS were selected based on the exclusion criteria from SEER. Kaplan-Meier survival analysis, log-rank test and Cox proportional hazards models were used to analyze all the data. Results Single PGS has an apparent popularity for the temporal lobe (35.2%, hazard ratio [HR] = 0.440, 95%CI = 0.251-0.770) and frontal lobe (20.9%, HR = 0.408, 95%CI = 0.231-0.720) which could achieve a better survival rate than cerebrum (P = .034). The mean age at diagnosis was 60.07 +/- 14.161. The overall 6-month, 1-year, 2-year, and 5-year survival was 55.40%, 29.58%, 10.01%, and 2.73%. Age at diagnosis was proved to be a significant predictor of overall survival (OS) (P < .001). There is no significant difference in race, marital status, or grade. Patients' tumor size which is located in 41-60 mm (P = .047, HR = 1.468, 95%CI = 1.004-2.147) and >60 mm (P= .003, HR = 1.899, 95%CI = 1.244-2.901) showed a higher risk of death. Surgery played a critical role in OS (P < .001). Radiation after surgery was another predictor of OS of PGS (P < .001). Among all the radiation methods, combination of beam with implants or isotopes (P = .000, HR = 0.491, 95%CI = 0.412-0.585) or radiation NOS (P = .027, HR = 0.362, 95%CI = 0.148-0.889) were more beneficial to patients. Conclusion This study indicated that single PGS has a poor prognosis. Prognosis of single PGS would become poorer along with patients' age and tumor size (>40 mm). Surgery intervention and radiation therapy were beneficial factors.