Glioblastoma (GBM) is the most common type of malignant primary brain tumors originating from glial cells. GBM is an aggressive and extremely invasive tumor with a very poor prognosis and median survival of 12.1-14.6 months. Surgery is a corner stone in the treatment of GBM. However, resection may be inapplicable for lesions located in eloquent gray matter such as brainstem, basal ganglia or thalamus. For unresectable tumors, treatment varies from short-course radiotherapy to extended-course radiotherapy and even combined radiochemotherapy. In this study, we compare radiotherapy alone with combined radiochemotherapy to determine patients’ survival with both treatments.
To identify patients with unresectable GBM, the Surveillance, Epidemiology and End Results database (SEER) of the National Cancer Institute was searched. Patients with an initial diagnosis of GBM between 2004 and 2013 were identified and their clinical characteristics were extracted from records for analysis.
A total number of 2562 patients with unresectable GBM was identified with a median age of 63 years and a median survival of 6 months. The most common sites for tumor was frontal lobe (23.2%) and overlapping lesion of brain (21.1%). Out of total, 548 (21.4%) with a median age of 69 years received radiotherapy alone and 2014 (78.6%) with a median age of 61 years received combined radiochemotherapy. Survival analysis showed that patients who received combined radiochemotherapy had better survival compared to whom received radiotherapy alone with 1-year relative survival of 32.3% and 11.5% and 2-year relative survival of 11.1% and 3.5% for combined radiochemotherapy group and radiotherapy alone group, respectively (p-value < 0.001).
The prognosis of patients with unresectable GBM is still very poor. Combined radiochemotherapy showed a significant better survival compared to radiotherapy alone.
Clinical trial identification
Legal entity responsible for the study
Mohamed H. Osman.
Has not received any funding.
The author has declared no conflicts of interest.