Construction and validation of a clinical prognostic model for frontal glioblastoma: a real-world clinical study based on radiation therapy.

Background: Glioblastoma has high malignancy, treatment challenge, poor prognosis and survival. It takes place mostly in the frontal lobe, and it significantly impacts late-life activities. Therefore, the establishment of a survival model for frontal glioblastoma patients is of great significance for optimizing the treatment for patients. The aim of this study is to identify risk factors for frontal glioblastoma, to construct survival models, and to provide strong evidence for patients and doctors to apply radiotherapy to frontal glioblastoma.

Methods: Independent risk factors for frontal glioblastoma patients were identified and survival models were constructed based on information obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Clinical data on patients pathologically diagnosed with frontal glioblastoma were screened. A nomogram was constructed based on the training group to verify the clinical validity of the model.

Results: A total of 2,063 patients were included. There were 1,444 patients assigned to the training group, according to a random number method, and the remaining 619 patients were included in the validation group. Cox multivariate analysis based on 1,444 data from the training group showed that age, tumor hemiorism, metastasis, surgery, chemotherapy and radiotherapy were significantly correlated with the prognosis, with P values less than 0.05. In the training group, the concordance index (C-index) for overall survival (OS) and cancer-specific survival (CSS) of the cohort was 0.712 and 0.710, respectively. Calibration, receiver operating characteristic curve and decision curve analysis for OS showed a good agreement between the actual and predicted probability of survival. A total of 225 cases were screened out for analysis after 1:1 matching with a caliper value of 0.02. The median survival time of patients receiving radiotherapy was 7 months and that of those without radiotherapy was 5 months, hazard ratio =1.067, P values less than 0.05.

Conclusions: Age over 60 years old, space-occupying lesions across the midline, surgery not performed, radiotherapy not performed, and without chemotherapy are poor prognostic factors for frontal glioblastoma patients. Radiation therapy can significantly improve OS and CSS in frontal glioblastoma patients. The nomogram developed in this study has the potential for clinical application.