Factors affecting survival in glioblastoma patients below and above 65 years of age: A retrospective observational study.

Background The purpose of this study is to identify the differences with respect to survival and prognostic factors in a comparison between radiotherapy-receiving glioblastoma (GBM) patients above and below 65 years of age. Methods The results of 157 patients with GBM were analyzed retrospectively. Patients were divided into two groups as those below and above 65 years of age. A comparison was drawn with respect to each group's demographic characteristics, treatment methods, and findings. Results Out of a total of 157 patients, 53 patients (33.8%) were above 65 years of age. Karnofsky performance status (KPS) was weaker among older patients (P = 0.002). On the other hand, with respect to radiotherapy dose, among older patient group, greater hypofractionation and whole-brain radiotherapy was applied (P = 0.003) compared with younger patients. The survival rates for 1, 2, and 5 years among patients aged <65 years were 63%, 30%, and 3%, respectively, and in patients aged ≥65 years were 43%, 13%, and 0%, respectively. In univariate analyses, a comparison between patients below and above 65 years of age revealed that values higher than 80 KPS (P = 0.002), applying total excision (P < 0.001), receiving concurrent chemotherapy (P = 0.004), receiving conventional radiotherapy (P < 0.001), and adjuvant chemotherapy (P < 0.001) were effective factors on overall survival rates. Conclusion In the patient group above 65 years of age, the patient should be attentively selected before opting for a specific treatment, age alone should not be the sole determinant factor. Rather, by considering the KPS scores, potential aggressive treatment options should also be applied.